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Despite previous treatment as herbivores, largely omnivorous tadpoles may exhibit both consumptive (CEs) and non-consumptive effects (NCEs), but the roles of additional biotic and abiotic factors in mediating these effects, such as body size and habitat shading, are poorly understood. We compared freshwater invertebrate abundance and community composition across tadpole body size and habitat shading treatments to assess whether these factors influence the strength of tadpole CEs and NCEs. Macroinvertebrate and zooplankton abundances and community composition were characterized in mesocosms with either large or small wood frog (Lithobates sylvaticus) tadpoles either shaded or not in separate CE (uncaged tadpole) and NCE (caged tadpole) treatments. Invertebrates were least abundant in mesocosms with larger tadpoles under shade. Macroinvertebrates suffered declines associated with CEs and NCEs, whereas zooplankton experienced positive NCEs but negative CEs. Our results suggest larger predators can predate more diverse prey (CEs) due to their wider gapes, but also that increased production of cues associated with predation risk can elicit stronger prey behavioral responses, such as changes in foraging time (NCEs). Predator body sizes and habitat shading are shifting with climate change, and such shifts may alter strength and direction of CEs and NCEs exerted by amphibians on freshwater invertebrates. [ABSTRACT FROM AUTHOR]

The Wadden Sea is the world's largest intertidal area and a UNESCO World Heritage Site. Macrozoobenthic invertebrates perform key ecological functions within intertidal areas by regulating nutrient cycles, decomposing organic matter, and providing food for fish, birds and humans. To understand ecological processes and human impacts on biodiversity, the Synoptic Intertidal BEnthic Survey (SIBES) has sampled intertidal macrozoobenthos since 2008. On average 4,109 stations across 1,200 km² of Dutch Wadden Sea mudflats are sampled from June to October to quantify the benthic invertebrate community and sediment composition, including species abundance and biomass, and grain size and mud content. The dataset published now contains 51,851 sampled stations with 3,034,760 individuals of 177 species. This paper details data collection, validation and processing methods. SIBES is ongoing and data will be updated yearly. In sharing these data, we hope to enhance collaborations and understanding of the impact of various pressures on macrozoobenthic invertebrates, sediment composition, food webs, the ecosystem, and biodiversity in the Wadden Sea and other intertidal habitats. [ABSTRACT FROM AUTHOR]

Simple Summary: Freshwater ecosystems are among the most severely affected environments by species loss. In this context, biomonitoring plays a key role by providing reliable data on biological diversity and ecological status. Environmental DNA (eDNA) metabarcoding is a powerful and non-invasive alternative to traditional morphology-based sampling and identification methods. This study represents the first application of eDNA analysis to assess the invertebrate communities in three Sicilian Lakes: Poma, Piana degli Albanesi and Scanzano. A total of 27 species were identified, belonging to Phyla of Annelida, Arthropoda and Rotifera. Moreover, the analysis revealed the presence of alien species, dangerous species associated with the transmission of viral diseases, and potential new records for Sicily. These results provide a preliminary snapshot of invertebrate biodiversity at these sites, demonstrating how eDNA has the potential to complement, but not replace, traditional methods. Freshwater ecosystems are among the most severely affected environments by species loss caused by climate change and intense anthropogenic pressure. To preserve biodiversity, biomonitoring plays a key role by providing reliable data on biological diversity and ecological status. Environmental DNA (eDNA) metabarcoding has emerged as a powerful and non-invasive alternative to traditional morphology-based sampling and identification methods. This study represents the first application of eDNA analysis to assess the invertebrate communities in three Sicilian Lakes: Poma, Piana degli Albanesi and Scanzano. Water samples were collected at two points in each lake and after filtration with nitrocellulose membranes, eDNA was extracted and metabarcoding analysis was performed. A total of 27 species were identified, belonging to Phyla of Annelida, Arthropoda and Rotifera. Notably, the analysis revealed the presence of alien species (Daphnia parvula and Acanthocyclops americanus), a dangerous species associated with the transmission of viral diseases (Culex pipiens), and potential new records for Sicily (Stylaria lacustris, Platypalpus exilis, Pammene aurana, Limnephilus rhombicus). These results provide a preliminary snapshot of invertebrate biodiversity at these sites, demonstrating how eDNA has the potential to complement, but not replace, traditional methods, contributing to the assessment of ecosystem status. [ABSTRACT FROM AUTHOR]

Copper-based plant protection products (PPPs) are widely used in both conventional and organic farming, and to a lesser extent for non-agricultural maintenance of gardens, greenspaces, and infrastructures. The use of copper PPPs adds to environmental contamination by this trace element. This paper aims to review the contribution of these PPPs to the contamination of soils and waters by copper in the context of France (which can be extrapolated to most of the European countries), and the resulting impacts on terrestrial and aquatic biodiversity, as well as on ecosystem functions. It was produced in the framework of a collective scientific assessment on the impacts of PPPs on biodiversity and ecosystem services in France. Current science shows that copper, which persists in soils, can partially transfer to adjacent aquatic environments (surface water and sediment) and ultimately to the marine environment. This widespread contamination impacts biodiversity and ecosystem functions, chiefly through its effects on phototrophic and heterotrophic microbial communities, and terrestrial and aquatic invertebrates. Its effects on other biological groups and biotic interactions remain relatively under-documented. [ABSTRACT FROM AUTHOR]

The article "Preface: Secrets of shallow lakes—insights from research" published in Hydrobiologia discusses the theme of 'Secrets of Shallow Lakes' and highlights the importance of ongoing research in understanding the mysteries of aquatic ecosystems. It emphasizes the need to monitor the health of water bodies, especially in the face of environmental problems and climate change. The article also provides insights from the 11th International Conference on Shallow Lakes held in Estonia, covering topics such as lake restoration, nutrient cycling, bioindicators, and mesocosm experiments. The research presented in the article underscores the complexity of lake ecosystems and the importance of integrated management approaches to protect and maintain ecological balance. [Extracted from the article]

Riparian ecosystems harbour unique biodiversity because of their close interconnections with adjacent aquatic ecosystems. Yet, how aquatic ecosystems influence terrestrial biodiversity over different spatial scales is poorly understood, particularly in the tropics. We conducted field campaigns to collect 235 terrestrial invertebrate assemblages along 150 m transects from 47 streams in both Brazil and the UK, compiling one of the largest known datasets of riparian invertebrate community composition at multiple spatial scales. Invertebrate densities increased towards water in both regions. In Brazil, this was driven by an increase in spiders, with a corresponding decrease in non-predators, resulting in higher predator : prey ratios near water. In the UK, non-predator densities increased towards water, decreasing predator : prey ratios. While pairwise dissimilarity increased with distance from water in both regions, β-diversity was significantly higher in tropical assemblages, with more β-diversity explained by turnover. Spider community composition was significantly structured by distance from water in the Brazilian sites, suggesting tropical assemblages were influenced more by emerging aquatic prey, with a distinct spider community replacing other predators, with possible top–down control of terrestrial prey. High turnover-driven dissimilarity among tropical assemblages suggests that Brazilian riparian ecosystems are better managed at the landscape scale, with an emphasis on in-stream measures preventing disruption of aquatic resource subsidies. [ABSTRACT FROM AUTHOR]

Simple Summary: Baseline data on stream habitats and aquatic invertebrate communities were needed prior to beginning corrective measures to restore a stream and river system in southeastern Minnesota, USA, impacted by channelization and agricultural runoff. Although >85% of habitat assessments rated stream sites as fair or good, >50% of invertebrate samples exhibited poor or very poor communities. Too many fine stream-bottom sediments (e.g., silt, sand), a lack of habitat diversity, and shallow water resulted in low invertebrate diversity and low numbers of pollution- or disturbance-sensitive species. Communities improved from upstream sites to downstream sites as the river landscape transitioned from a dominance of row-crop agriculture to a more forested drainage with increased coldwater inputs from groundwater springs. Action is needed to reduce channelization disturbances and soil erosion from agricultural fields, especially in the headwaters, before aquatic invertebrate communities can recover. Prior to implementing watershed-wide projects to reduce the impacts of agriculture on regional streams and rivers, stream habitats and benthic aquatic macroinvertebrate communities were assessed at 15 sites on the South Branch Root River and its major tributaries in southeastern Minnesota, USA. Triplicate kick-net samples were collected from each site during three time periods (1998, 1999, 2006/2008) and stream habitats were inventoried within 150 m long sections at each site. In total, 26,760 invertebrates representing 84 taxa were collected and used to rate stream sites using a regional multi-metric benthic index of biotic integrity (BIBI). BIBI scores were significantly correlated with total invertebrate taxa richness. BIBI ratings improved from poor and very poor at headwater sites in channelized stream sections draining agricultural lands to fair to good to excellent in downstream sections flowing through natural channels in largely forested lands. Fifty percent of samples rated stream sites as poor or very poor. Over 85% of stream habitat assessments indicated the presence of fair to good habitats, although stream sites were relatively wide and shallow and dominated by fine sediments that also embedded coarser substrates. BIBI metrics and scores were strongly positively correlated with pool area, riffle spacing-to-stream width ratios, and silt-free substrate, and negatively correlated with width-to-depth ratios. Most stream sites had few Ephemeroptera, Plecoptera, Trichoptera, and Diptera taxa and too few intolerant taxa. It is expected that benthic invertebrate communities should improve as more riparian buffers are added along all streams. However, on-going channel maintenance activities in headwater stream sections, mandated to encourage drainage of adjacent agricultural fields, will continue to negatively impact headwater habitats and biotic communities. [ABSTRACT FROM AUTHOR]

Shaffer, J.A.; Oxborrow, B.; Parks, D.S.; Maucieri, D.G., and Michel, J., 2025. Linking marine ecosystem response to shoreline armor removal and large dam removals in the Elwha River and nearshore, Washington, USA. Journal of Coastal Research, 41(1), 1–15. Charlotte (North Carolina), ISSN 0749-0208. Large in-river dams and shoreline armor have a significant negative effect on coastal hydrodynamic and ecosystem processes. Armor removal (AR) is a well-documented shoreline restoration tool, and removal of large dams is proving to be an extremely effective tool to restore riverine ecosystem processes. However, nearshore ecosystem restoration associated with dam removals (DRs) is incomplete when shoreline impediments, including shoreline armoring and lower river alterations, remain, and linkages between dam and shoreline ARs are not well understood. In this study, nearshore ecosystem processes and function restoration response to large DRs and shoreline AR are assessed. Two nearly century-old large dams in the Elwha River watershed in the NW United States were removed during 2011–14, which liberated upward of 18 million tonnes (Mt) or approximately ∼9 million m3 of silt, sand, and gravel to sediment-starved, armored, and unarmored shorelines. Within 1 year of the initiation of DR, unarmored shorelines in the drift cell broadened, flattened, sediment fined, and large woody debris (LWD) volumes significantly increased. Armored shorelines continued to be steep and coarse grained. In 2016–17, approximately 4700 m3 of large riprap (shoreline armor) was removed from more than 650 m of the armored Elwha River east delta reach drift cell. Following AR, previously eroding shorelines broadened, sediment fined, LWD volumes increased significantly, and beach wrack metrics resembled non-armored beaches. These changes followed AR and did not occur at unarmored DR or control treatments. Invertebrate communities also responded to dam and armor removal (DAR) and showed increasing trends every year for 3 years after the project. It is concluded that only partial nearshore ecosystem restoration occurs from large DR when shoreline armoring that impairs nearshore hydrodynamic processes remains and that full ecosystem restoration of the nearshore associated with large DRs is obtained by restoring impaired shorelines along with DRs. [ABSTRACT FROM AUTHOR]

Marine microbial communities colonizing the skin of invertebrates constitute the primary barrier between host and environment, potentially exerting beneficial, neutral, or detrimental effects on host fitness. To evaluate the potential contribution of epibiotic bacteria to the survival of early developmental stages of Octopus mimus, bacterial isolates were obtained from eggs, paralarvae, and adults. Their enzymatic activities were determined, and antibacterial properties were assessed against common marine pathogens. The isolates belonged to the phyla Proteobacteria, Actinomycetota, Bacteroidota, and Bacillota, represented by 21 genera and 27 species. Specific taxa were associated with each developmental stage, with only three species shared among different stages: Bacillus pumilus, B. megaterium, and Shewanella algae, which also inhibited the growth of all assayed pathogens. Organic extracts from Bacillus megaterium M8-1 were obtained, and UHPLC-MS analysis detected seventeen putative compounds, including two phenolic acids, three indole derivatives, and twelve oxylipins. Our findings provide novel data on cultivable bacterial representatives isolated from Octopus mimus capable of synthesizing chemical compounds with bioactive properties. These results contribute to a better understanding of the role of microbial communities in the survival of this invertebrate species during critical early life stages. [ABSTRACT FROM AUTHOR]

Community ecology has so far struggled to integrate both deterministic and stochastic processes into a global model of community variation. To address this issue, we aimed to characterise the ecological conditions that determine the relative importance of deterministic and stochastic community variation in benthic macroinvertebrates. We sampled macroinvertebrate and algal periphyton communities, and microhabitat conditions at monthly intervals over a five year period in two sampling sites in the regulated Durance River and one site in the Asse River (a natural tributary of the Durance). The relative importance of stochastic and deterministic processes was estimated over time as functional and taxonomic spatial β‐deviation (i.e. β‐diversityobs − mean β‐diversitynull/SD β‐diversitynull) for each sampling date and site. We additionally quantified deterministic variation as the trait–environment relationship and predicted a positive correlation with β‐deviation metrics. We found evidence of overdispersal in both functional and taxonomic β‐diversities compared to null expectations. Spatial β‐deviation was highly variable over temporal scales and was jointly explained by invertebrate community size, disturbance (i.e. flooding), periphyton diversity and to a lesser extent, microhabitat diversity. The key factor that explained β‐deviation was recent river discharge (< 90 days), which had a strong negative effect on community size but was also directly associated with higher β‐deviation, likely related to recolonization processes post‐flood. Lastly, we found that when β‐deviation was high, the hydraulic trait–environment relationship was stronger. This indicates that spatial heterogeneity in hydraulic conditions was the main driver of deterministic variation in invertebrate community structure. This study demonstrates that the importance of stochastic processes can vary greatly over short (~ months) and long (~ years) temporal windows with significant consequences for trait–environment relationships. Our study provides an example of how stochastic community variation can be modelled to better interpret deterministic patterns of community structure in natural communities. [ABSTRACT FROM AUTHOR]

Shallow lakes, including those located at the border between Europe and Asia (Kazakhstan), have become very prone to increasing salinity because of climate change. Most of the study area is in one of the fastest-warming parts of the globe. Our research, conducted in four lakes varying in water salinity level and located in western Kazakhstan in the steppe, semi-desert, and desert zones, can be used to predict biodiversity as indicators of the natural potential of ecosystems. This was achieved by assessing the associations of invertebrate communities with environmental conditions based on data collected during nine seasonal measurement campaigns (in May, July, and September of 2019, 2020, and 2021). The multidimensional scaling (nMDS) of biotic and abiotic data enabled us to identify lakes as freshwater (1), oligohaline (1), and mesohaline (2). The key classifier was biotope salinity, irrespective of lake location in the steppe, semi-desert, or desert zones. Twenty-nine taxa were identified in the freshwater lake, 37 in the oligohaline, and 24–28 in the mesohaline lake; these accounted for ~ 80% of their estimated taxonomic composition, according to Species Accumulation Curves (SAC). The differences in the structure of benthic invertebrate assemblages revealed between the lakes are mainly concerned with the density and, to a lesser extent, the diversity of communities (Simpson index). As the salinity of the waters increased, the proportion of Diptera larvae significantly increased, and that of Ephemeroptera larvae decreased. Sigara assimilis, accompanied by Sphaeromas sp., Chironomus sp., and Saeharia sp., proved strongly resistant to increased water salinity. Among the studied lakes, the semi-desert lake Balykty Sarkyl (β-mesohaline) is strongly threatened by biodiversity degradation due to unfavourable climatic conditions. Time series analysis for Lake Edilsor (α-mesohaline) shows that it underwent the most rapid salinisation, which has increased the number of taxa tolerant to this predictor (mainly Diptera larvae). The results confirm that detailed taxonomic assessment (including time series) can significantly improve our understanding of lake changes with increasing salinity caused by climate change and/or other stressors. [ABSTRACT FROM AUTHOR]

The forest canopy is populated by diverse communities of invertebrate animals, some of which are traditionally regarded as soil-dwellers. This phenomenon has been revealed for Oribatida and Collembola, but information about the diversity and distribution of free-living nematodes on tree bark and in epiphytes remains limited and fragmentary. In this study, we used DNA metabarcoding to assess diversity patterns of free-living nematodes in the canopy and compared them with soil communities in a boreal, temperate, and tropical monsoon forest. Our results indicate that compared to soil communities, arboreal nematodes exhibit strongly reduced alpha diversity, but increased beta diversity, while the total number of nematode OTUs is comparable in soil and the forest canopy. Considering the low taxonomic similarity (23–29%) between nematode communities in the soil and canopy, it is evident that arboreal habitats contribute significantly to the overall diversity of nematodes in forest ecosystems. In contrast to the soil nematode communities, there was no latitudinal diversity gradient in the canopy of the studied forests. Moreover, there was no decrease in the nematode OTU diversity with height, indicating that arboreal communities of nematodes and microarthropods are controlled by different mechanisms. [ABSTRACT FROM AUTHOR]

Diel partitioning of animals within ecological communities is widely acknowledged, yet rarely quantified. Investigation of most ecological patterns and processes involves convenient daylight sampling, with little consideration of the contributions of nocturnal taxa, particularly in marine environments. Here we assess diel partitioning of reef faunal assemblages at a continental scale utilizing paired day and night visual census across 54 shallow tropical and temperate reefs around Australia. Day–night differences were most pronounced in the tropics, with fishes and invertebrates displaying distinct and opposing diel occupancy on coral reefs. Tropical reefs in daytime were occupied primarily by fishes not observed at night (64% of all species sighted across day and night, and 71% of all individuals). By night, substantial emergence of invertebrates not otherwise detected during sunlit hours occurred (56% of all species, and 45% of individuals). Nocturnal emergence of tropical invertebrates corresponded with significant declines in the richness and biomass of predatory and herbivorous diurnal fishes. In contrast, relatively small diel changes in fishes active on temperate reefs corresponded to limited nocturnal emergence of temperate invertebrates. This reduced partitioning may, at least in part, be a result of strong top‐down pressures from fishes on invertebrate communities, either by predation or competitive interference. For shallow reefs, the diel cycle triggers distinct emergence and retreat of faunal assemblages and associated trophic patterns and processes, which otherwise go unnoticed during hours of regular scientific monitoring. Improved understanding of reef ecology, and management of reef ecosystems, requires greater consideration of nocturnal interactions. Without explicit sampling of nocturnal patterns and processes, we may be missing up to half of the story when assessing ecological interactions. [ABSTRACT FROM AUTHOR]

There is a significant lack of knowledge about the communities of mesoinvertebrates associated with the composting process. Here we evaluate the presence of mesoinvertebrates during the the composting process in two compost piles: 1) a pile of spent substrate from oyster mushroom cultivation (S), and 2) a pile of spent substrate from oyster mushroom cultivation + beer bagasse (S + B), without replicates. Composting was carried out in covered piles with weekly turnings. Temperature and humidity were estimated weekly in the center of each pile. Samples were taken at 0, 20, 30, 40, 60, 100, and 120 days from the center of the pile to estimate pH, conductivity, organic C, total Kjeldahl N, and extractable Olsen P. Additionally, samples of the material were placed in Berlese funnels to obtain the invertebrates. Finally, the size and density of microplastics (<5 mm) were determined at the beginning and end of the composting process for both piles. The composting process lasted 120 days. The thermophilic phase lasted 30-40 days and the temperature exceeded 45°C. In both piles, the disappearance of mesoinvertebrates coincided with the thermophilic stage. A peak in mesoinvertebrate density was observed three weeks after the end of the thermophilic stage. The dominant groups were Collembola both in S and Acari in S + B compost piles. Our work verified the presence of 0.8-3.8 microplastics particles per gram of compost in both piles, which may negatively interact with the mesoinvertebrates due to their size (0.02-1.4 mm). We need to carry out more studies on the dynamics of invertebrate communities and microplastics during the controlled decomposition processes of composting, as well as the interaction between them. [ABSTRACT FROM AUTHOR]

Leaf litter breakdown is a critical process in streams, as it plays a significant role in influencing food webs and biogeochemical cycles. Highland grasslands are often understudied landscapes, yet they are an excellent model system for evaluating how natural differences in riparian forest cover can influence litter breakdown in streams. We experimentally examined the effects of the presence and absence of riparian forest on temporal leaf litter breakdown and the associated biota in highland grassland streams. The 3-year experiment examined leaf litter breakdown in three stream reaches with riparian forest and three without. The results indicate that temperature could potentially mediate the temporal dynamics of leaf litter breakdown (mainly fine mesh) and the associated biota in highland grassland streams. No differences were found in leaf breakdown between stream reach types, but there was evidence of an increase in invertebrate density. Finally, leaf litter breakdown in the highland grasslands was more affected by annual variation than riparian forest presence, suggesting a context-dependent relationship. [ABSTRACT FROM AUTHOR]

Aim: To determine which riverine invertebrate traits respond consistently to anthropogenic impacts across multiple biogeographic regions. Location: Europe. Time Period: 1981–2021. Major Taxa Studied: Riverine invertebrates. Methods: We compiled a database of riverine invertebrate community time series for 673 sites across six European countries spanning six freshwater ecoregions. We compared trait responses to anthropogenic impacts (quantified as changes in 'ecological quality') among regions for seven 'ecological' traits, which reflect habitat preferences, and nine 'biological' traits (e.g., morphology or life history), which represent taxon‐specific attributes that can influence ecosystem processes. Results: Four ecological traits (current, microhabitat, salinity and trophic preferences) and one biological trait (dispersal mode) responded consistently across regions. These responses were primarily driven by spatial differences among poorer to better quality sites. Responses to temporal changes in quality were comparable but less pronounced. Main Conclusions: Consistent responses to anthropogenic impacts across multiple ecological traits indicate these traits may improve broader scale measurements, comparisons and predictions of community responses. However, we could not use ecological traits to identify the actions of specific stressors because multiple traits always responded as a group. Inconsistent responses across almost all biological traits indicated that these traits may be less predictive of impacts across regions. Predictions of how biological traits, and associated ecosystem processes, respond to anthropogenic impacts may be most effective at regional scales where responses are more consistent. [ABSTRACT FROM AUTHOR]

Aim: Biogenic structural complexity increases mobile animal richness and abundance at local, regional and global scales, yet animal taxa vary in their response to complexity. When these taxa also vary functionally, habitat structures favouring certain taxa may have consequences for ecosystem function. We characterised global patterns of epifaunal invertebrates in eelgrass (Zostera marina) beds that varied in structural and genetic composition. Location: North America, Europe and Asia. Time Period: 2014. Major Taxa Studied: Peracarid crustaceans and gastropod molluscs. Methods: We sampled epifaunal invertebrate communities in 49 eelgrass beds across 37° latitude in two ocean basins concurrently with measurements of eelgrass genetic diversity, structural complexity and other abiotic and biotic environmental variables. We examined how species richness, abundance and community composition varied with latitude and environmental predictors using a random forest approach. We also examined how functional trait composition varied along with community structure. Results: Total species richness decreased with latitude, but this was accompanied by a taxonomic shift in dominance from peracarid crustaceans to gastropods, which exhibited different sets of functional traits. Greater eelgrass genetic diversity was strongly correlated with both richness and abundance of peracarids, but less so for gastropods. Main Conclusions: Our results add to a growing body of literature that suggests genetic variation in plant traits influences their associated faunal assemblages via habitat structure. Because peracarids and gastropods exhibited distinct functional traits, our results suggest a tentative indirect link between broad‐scale variation in plant genetic diversity and ecosystem function. [ABSTRACT FROM AUTHOR]

Predators regulate communities through top‐down control in many ecosystems. Because most studies of top‐down control last less than a year and focus on only a subset of the community, they may miss predator effects that manifest at longer timescales or across whole food webs. In southeastern US salt marshes, short‐term and small‐scale experiments indicate that nektonic predators (e.g., blue crab, fish, terrapins) facilitate the foundational grass, Spartina alterniflora, by consuming herbivorous snails and crabs. To test both how nekton affect marsh processes when the entire animal community is present, and how prior results scale over time, we conducted a 3‐year nekton exclusion experiment in a Georgia salt marsh using replicated 19.6 m2 plots. Our nekton exclusions increased densities of plant‐grazing snails and juvenile deposit‐feeding fiddler crab and, in Year 2, reduced predation on tethered juvenile snails, indicating that nektonic predators control these key macroinvertebrates. However, in Year 3, densities of mesopredatory benthic mud crabs increased threefold in nekton exclusions, erasing the tethered snails' predation refuge. Nekton exclusion had no effect on Spartina biomass, likely because the observed mesopredator release suppressed grazing snail densities and elevated densities of fiddler crabs, whose burrowing alleviates soil stresses. Structural equation modeling supported the hypotheses that nektonic predators and mesopredators control invertebrate communities, with nektonic predators having stronger total effects on Spartina than mud crabs by controlling densities of species that both suppress (grazers) and facilitate (fiddler crabs) plant growth. These findings highlight that salt marshes can be resilient to multiyear reductions in nektonic predators if mesopredators are present and that multiple pathways of trophic control manifest in different ways over time to mediate community dynamics. These results highlight that larger scale and longer‐term experiments can illuminate community dynamics not previously understood, even in well‐studied ecosystems such as salt marshes. [ABSTRACT FROM AUTHOR]

The rise in human population has led to the expansion of settlements and an increase in the types and amounts of wastes released into the aquatic environment. Bivalves have an important place among the invertebrate communities of freshwater environments. Mussels remove suspended substances from the water and contribute significantly to the regulation of the physical properties of water. This study was conducted to determine the microbiome load in the intestinal tissue of the freshwater mussel Unio stevenianus (Bivalvia: Unionidae) living in Karasu River. Amplification of the V3–V4 region of the bacterial 16S rRNA gene fragment was performed in tissue samples. Bacterial species were divided into operational taxonomic units using the Kraken metagenomics program. The percentage bacterial distribution with the highest reading sequence at the phylum level was determined as Bacteroidota > Bacillota > Pseudomonadota > Actinomycetota > Cyanobacteriota > Campylobacterota in Arısu samples; while in Zeve samples, it was determined as Pseudomonadota > Actinomycetota > Bacillota > Bacteroidota > Cyanobacteriota > Campylobacterota. The detection of various bacterial phylum indicates that the water environment in which the mussel samples were collected is exposed to a large number of bacterial sources, especially domestic waste. The continued existence of freshwater mussels is necessary for them to fulfill their important duties in the ecosystem. To achieve this, uncontrolled and untreated waste discharges should be abandoned. Pollutants in the water and mussel populations should also be monitored through a monitoring program. [ABSTRACT FROM AUTHOR]

In response to the mounting ecological and economic impacts of aquatic invasive plants, management actions now include a wide array of mechanical, physical, biological, and chemical control strategies. Diver-assisted suction harvesting (DASH) is a common physical approach but is well acknowledged to be labor intensive, costly, and to exert a high physical toll on divers. These limitations have sparked technological innovation in the form of prototyping a new methodology called autonomous suction harvesting (ASH) that replaces the diver with a remotely operated vehicle. The present study evaluated the efficiency, effectiveness, and unintended ecological effects of DASH and ASH when used to control nonnative Myriophyllum spicatum L. According to this field-based experiment conducted in Star Lake, Washington, USA, both suction harvesting methods suppressed the biomass of M. spicatum , but with some key differences. Harvest efficiency was 2× greater for DASH (10.3 kg/h) compared with ASH (5.0 kg/h), which was a result of additional time needed for the remotely operated vehicle to navigate submerged obstacles (e.g., logs) when abundant in the littoral zone. Suppression effectiveness of both approaches was similarly encouraging. Assessed 1 y after treatment, stands subject to either DASH or ASH methods had lower M. spicatum densities compared with control stands, which showed substantial natural increases over time. Stem fragmentation occurred during suction harvesting, and floating M. spicatum fragments not successfully removed averaged ∼20% (ASH) and ∼2% (DASH) of the total biomass harvested. Nontarget plants were also accidentally harvested during the treatments, with biomass ranging between 1 and 4× greater than M. spicatum biomass harvested. Macrophyte and epiphytic invertebrate community composition assessed 1 y after treatment showed no change when subject to either DASH or ASH. The present study offers an early proof-of-concept evaluation of ASH to suppress M. spicatum and highlights opportunities to improve the efficiency and effectiveness of this novel approach. Given that the growing challenges of aquatic invasive plants are outpacing current management strategies, developing innovative technological solutions provides an exciting research frontier in the freshwater sciences. [ABSTRACT FROM AUTHOR]

Disturbances are drivers of ecosystem function and play important roles in shaping ecological communities. Prescribed fire and grazing disturbances are common management tools in restored and remnant grasslands. The effects of these management actions on plant communities and on vegetation-dwelling invertebrates are generally well studied. However, less is known about their effects on ground-dwelling invertebrates, which can contribute to important ecosystem processes like herbivory, predation, and decomposition. We examined bison grazing and prescribed fire effects on abundance, diversity, and community composition of ground-dwelling invertebrate groups in restored tallgrass prairies using pitfall trap samples. Surprisingly, invertebrate Shannon diversity decreased when bison were present and was unaffected by fire or the fire–bison interaction. Bison, and to a lesser extent fire, also shifted community composition, increasing abundance of ground, rove, and dung beetles, as well as orthopterans and spiders. Prescribed fire generally increased beetles but caused declines in several ecologically diverse invertebrate groups, including harvestmen and true bugs, although these reduced abundances did not lead to differences in overall diversity. Bison presence may amplify the abundances of dominant groups, such as ground and dung beetles and orthopterans, that outcompete other invertebrates and reduce diversity. Implications for insect conservation: Prescribed fire and grazing by bison change ground-dwelling invertebrate community composition, but bison presence did not reduce the abundance of most taxonomic groups. Fire may have short-term negative impacts on some invertebrate groups that promote desirable invertebrate-driven ecosystem processes, but these effects are likely short-lived, and the resulting environmental mosaic under bison and fire management could support biodiversity over the long-term. [ABSTRACT FROM AUTHOR]

Soil fauna is integral to facilitating material cycles, energy flows, and the conservation of biodiversity in terrestrial ecosystems. However, the impacts of forest development on the compositions and structures of soil invertebrates remain uncertain. Here, we assessed the dynamics in abundance and diversity of soil invertebrates across eight successional age stages of Metasequoia glyptostroboides tree plantations (7-, 16-, 21-, 26-, 31-, 36-, 41-, 46-year-old stands) in a reclaimed coastal land in China. We used pitfall traps to collect soil invertebrates and analyzed key soil and litter properties to understand their relationships with the faunal communities. The results revealed that the total abundance of soil invertebrates initially decreased during the young to near-mature stand period (7- to 31-year-old stands), whereas it increased along the age series, from the near-mature to overmature stand period (31- to 46-year-old stands). Specifically, the dynamics showed a U-shaped curve with stand development. Further, there was a significantly negative correlation between the Shannon–Wiener diversity index and the total abundance of soil invertebrates across this plantation chronosequence. The variations in abundance of detritivores were consistent with the total abundance of soil invertebrates during stand development. The abundance and diversity of the soil invertebrates were strongly correlated with the soil environment (e.g., soil organic carbon, litter biomass, and microbial biomass nitrogen). These findings highlight that the compositions and structures of soil invertebrates were significantly altered with M. glyptostroboides stand development. Thus, the management of plantations should consider the abundance and diversity of soil invertebrates and functional groups for improving soil structure and fertility. This provides important insights for studying the interconnection of above- and below-ground plantation ecosystems toward their optimal management. [ABSTRACT FROM AUTHOR]

The transition from a perennial to an intermittent regime in newly intermittent rivers (nIRs) negatively affects both taxonomic and functional diversity, with significant repercussions on freshwater ecosystem processes and services. However, to better understand how changes in the natural flow regime may influence the structure and functioning of freshwater ecosystems, it is fundamental to assess variations in abiotic and biotic parameters throughout the hydrological phases characterizing nIRs. For these reasons, we evaluated the temporal changes in community structure and composition during the drying phase of a Central Apennines stream (Italy) over two consecutive drought years. We demonstrated that the different hydrological regime of the pre-drought phase profoundly affected the structure and composition of freshwater communities. The reduced discharge during the low-flow conditions of 2024 led to a transition from insect- to non-insect-dominated communities, with small-sized, lentic-adapted and generalist taxa replacing rheophile and more sensitive insect taxa. We also found marked interannual differences in temporal beta diversity. However, in both years, taxa richness did not exhibit a negative stepped response pattern during the sequence of channel contraction, flow cessation and pools formation. Consequently, we can assume that in newly intermittent Apennine rivers, the response of freshwater communities to drying is strictly dependent on the local and interannual variable hydrological context. This study emphasizes the need for further investigation to better understand the ecological impacts of increasing intermittence in formerly perennial streams and rivers. [ABSTRACT FROM AUTHOR]

Solonchaks are soils characterized by high concentrations of soluble salts. These soils form unique ecosystems that provide habitats for organisms adapted to such extreme conditions. Invertebrates are one of the groups of organisms that inhabit these soils and play a significant role in ecosystem resilience contributing to soil health and fertility. However, the diversity of invertebrates inhabiting the solonchaks remains underexplored. The development of eDNA metabarcoding method has facilitated the detection of soil invertebrates, overcoming the limitations of conventional labor-intensive and time-consuming methods. eDNA metabarcoding made it possible to study/monitor changes in soil invertebrate diversity. This pilot study employed eDNA metabarcoding to detect soil invertebrates in solonchak soils at two agricultural fields in Vojvodina, Serbia. Furthermore, we compared two analytical methods of eDNA metabarcoding data – clustering and denoising sequences. eDNА metabarcoding method proved to be effective in detection of invertebrates. Using BOLD database, 0.21% OTUs and 0.11% ESVs were successfully assigned to expected Invertebrate phyla (Arthropoda, Annelida and Nematoda), with two specific species identified: Aporrectodea jassyensis and Sminthurinus elegans. Comparison of the two analytical approaches, denoising and clustering, revealed that these approaches identified the same taxonomic categories. However, given the limited sample size, further studies should compare these two approaches using a more extensive dataset to better estimate their usefulness. [ABSTRACT FROM AUTHOR]

Gravel roads are a common feature in developed areas of Canada's Arctic. These roads can be a source of calcareous dust that drifts to roadside lakes, causing significant changes in conductivity, calcium, and pH levels. In this study, we examined if road proximity was associated with differences in water quality and invertebrate communities in lakes along the Dempster and Inuvik-Tuktoyaktuk Highways in the Northwest Territories, Canada. We collected biological and water quality data from 18 lakes selected using a stratified random sampling design, with distance from the road (0–300 m, 300–600 m, and >600 m) and region of study (boreal forest, tundra) as the two factors. We hypothesized that lakes closer to the road would exhibit differences in water quality and invertebrate communities associated with road dust pollution and other stressors caused by roads. We found no clear differences in water quality or invertebrate communities among lakes based on distance from the highways. In addition, while there were differences between regions, these did not appear to be related to the effects of the roadways. Our results suggest that variability in lake morphometry and water quality in this region might be more important than the influence of roads. [ABSTRACT FROM AUTHOR]

Habitat loss can lead to biotic homogenization (decrease in β diversity) or differentiation (increase in β diversity) of biological communities. However, it is unclear which of these ecological processes predominates in human‐modified landscapes. We used data on vertebrates, invertebrates, and plants to quantify β diversity based on species occurrence and abundance among communities in 1367 landscapes with varying amounts of habitat (<30%, 30−60%, or >60% of forest cover) throughout the Brazilian Atlantic Forest. Decreases in habitat amount below 30% led to increased compositional similarity of vertebrate and invertebrate communities, which may indicate a process of biotic homogenization throughout the Brazilian Atlantic Forest. No pattern was detected in plant communities. We found that habitat loss was associated with a deterministic increase in faunal community similarity, which is consistent with a selected subset of species being capable of thriving in human‐modified landscapes. The lack of pattern found in plants was consistent with known variation between taxa in community responses to habitat amount. Brazilian legislation requiring the preservation of 20% of Atlantic Forest native vegetation may be insufficient to prevent the biotic homogenization of faunal communities. Our results highlight the importance of preserving large amounts of habitat, providing source areas for the recolonization of deforested landscapes, and avoiding large‐scale impacts of homogenization of the Brazilian Atlantic Forest. [ABSTRACT FROM AUTHOR]

In recent decades, the locally extinct sea otter (Enhydra lutris lutris) has been recolonizing the coast of eastern Hokkaido. Their diet includes benthic invertebrates such as bivalves, sea urchins, snails, and chitons. In the fall of 2021, a harmful algal bloom (HAB) of Karenia selliformis occurred across Hokkaido's northern and eastern coasts, leading to a massive mortality of sea urchins. This dinoflagellate produces a neurotoxin (gymnodimine) implicated in shellfish poisoning. To determine the effect of the HAB on the marine community, we conducted benthic surveys using SCUBA and visually monitored the prey items of the sea otters in the affected area from 2020 to 2023. Following the HAB, we observed an 82% decrease in benthic sea urchin density (number m2), leading to their complete absence from the diet of sea otters. Conversely, bivalve density increased six-fold, accompanied by a nearly two-fold rise in their percentage in the sea otters' diet. Minimal changes were observed in the density of chitons and snails, with no significant alteration in the sea otters' diet. Despite these changes, the impact of the HAB on otters' dietary preferences was temporary, as the percentage of dietary sea urchins began recovering one year later. Sea otters augmented their diet with bivalves to compensate for the reduced availability of sea urchins during the HAB with no apparent effects on the number of sea otters or their health. Our results highlight the adaptability of sea otters to adjust their diet according to prey availability. [ABSTRACT FROM AUTHOR]

Trout-perch (Percopsis omiscomaycus) is an abundant, small-bodied, benthic fish species often found in deeper regions of large lake ecosystems. Historical evidence suggests that Trout-perch may participate in nearshore lake food webs by migrating from deep to shallow areas at night. However, little is known about Trout-perch ecology or their potential role in nearshore food webs. We used Trout-perch abundance estimates, diet analysis, and benthic invertebrate community surveys to (1) assess Trout-perch trophic ecology in Lake Champlain, USA/CAN, and (2) determine whether deepwater prey resources existed at sufficient densities to support Trout-perch populations or whether supplemental prey resources were required. Trout-perch showed variability in size and biomass across lake regions, but diet patterns were largely consistent across the lake, with > 50% of diets consisting of emergent insect larvae and oligochaetes. Results suggest that migrations into nearshore habitats may be required to sustain Lake Champlain's Trout-perch populations, and therefore, Trout-perch could function as conduits of allochthonous energy across distinct lake habitat boundaries. This study is one of only a few that have examined the trophic ecology of Trout-perch in deep lakes and fundamentally improves our understanding of energy flow and coupling between distinct lake food web compartments in large lakes. [ABSTRACT FROM AUTHOR]

Organismal communities associated with coral reefs, particularly invertebrates and microbes, play crucial roles in ecosystem maintenance and coral health. Here, we characterized the organismal composition of a healthy, non-urbanized reef (Site A) and a degraded, urbanized reef (Site B) in the Gulf of Eilat/Aqaba, Red Sea to assess its impact on coral health and physiology. Biomimetically designed terracotta tiles were conditioned for 6 months at both sites, then reciprocally transplanted, and scleractinian coral species, Acropora eurystoma and Stylophora pistillata, were attached for an additional 6 months. After 12 months, tiles from Site A transplanted to Site B exhibited greater invertebrate richness and diversity than Site B's original tiles (via Cytochrome c. Oxidase subunit I metabarcoding). Key bacteria from the healthy reef were more prevalent on Site A tiles and on the tiles transplanted to Site B (via 16S rRNA gene sequencing). Corals originally from Site B attached to transplanted healthy tiles (Site A) showed higher photochemical capacity, increased endosymbionts, and reduced physiological stress, measured by total antioxidant capacity and an integrated biomarker response. Our findings demonstrate the successful transfer of organismal communities between reefs, highlighting the potential benefits of healthy reef-associated invertebrates and microbes on coral physiology and their implications for reef restoration strategies. Invertebrate and microbe communities support reef ecosystems and coral health. Here, the authors characterize these communities from degraded and healthy reefs, showing that transplanting these healthy communities improved coral health at degraded reefs. [ABSTRACT FROM AUTHOR]

The geographic ranges of slimy (Uranidea cognata) and mottled (Uranidea bairdii) sculpin overlap broadly across cool and coldwater streams and rivers in North America, where they can serve very important roles in fish community dynamics. The diet diversities of slimy and mottled sculpin were examined in early March (late winter) during eight out of nine years after the August 2007 catastrophic flooding in four streams to assess potential diet shifts as benthic invertebrate prey communities recovered post-flood. In total, 10,823 prey items, representing 39 invertebrate taxa and three fish taxa were identified from the stomachs of 532 slimy sculpins (present in Garvin Brook, Gilmore Creek, and Trout Run) and 179 mottled sculpins (present in Middle Fork Whitewater River). Only four prey taxa were consumed by sculpin in all streams: midge larvae and pupae (Diptera: Chironomidae), blackfly larvae and pupae (Diptera: Simuliidae), Hydropsyche caddisfly larvae (Trichoptera: Hydropsychidae), and Baetis mayfly nymphs (Ephemeroptera: Baetidae). Midges dominated diets of both slimy (61% of prey by number) and mottled (76%) sculpin across all years. Consequently, Shannon diversities of diets were typically low across all years and streams for slimy sculpin (annual site range 0.07–0.83) and across years for mottled sculpin (annual range 0.11–0.46). Diversities and taxa richness of slimy sculpin diets increased in Garvin Brook and Trout Run across the study years (driven by significant declines in midge dominance) but remained relatively unchanged for slimy sculpin in Gilmore Creek and mottled sculpin in the Middle Fork. Individual slimy and mottled sculpin differed significantly both in the numbers of taxa consumed per fish (<2 versus 2.5 taxa/fish, respectively) and in the numbers of individual prey per fish (11 versus 26 prey, respectively). Slimy sculpin in two streams displayed modest shifts in diets as benthic prey communities recovered during the 9-year period post-flood, whereas slimy and mottled sculpin in other streams displayed little to no changes in diets. Differing flood severity among streams may have produced the different responses observed in sculpin diets. [ABSTRACT FROM AUTHOR]

Drought is an increasing risk to the biodiversity within rivers—ecosystems which are already impacted by human activities. However, the long‐term spatially replicated studies needed to generate understanding of how anthropogenic stressors alter ecological responses to drought are lacking.We studied aquatic invertebrate communities in 2500 samples collected from 179 sites on rivers emerging from England's chalk aquifer over three decades. We tested two sets of alternative hypotheses describing responses to and recovery from drought in interaction with human impacts affecting water quality, fine sediment, water temperature, channel morphology, flow and temporal change in land use. We summarized communities using taxa richness, an index indicating tolerance of anthropogenic degradation (average score per taxon, ASPT) and deviation from the average composition.Responses to drought were altered by interactions with human impacts. Poor water quality exacerbated drought‐driven reductions in taxa richness. Drought‐driven deviations from the average community composition were reduced and enhanced at sites impacted by flow augmentation (e.g. effluent releases) and flow reduction (e.g. abstraction), respectively.Human impacts altered post‐drought recovery. Increases in richness were lower at sites impacted by water abstraction and higher at sites with augmented flows, in particular as recovery trajectories extended beyond 3 years. ASPT recovered faster at sites that gained woodland compared to urban land, due to their greater recovery potential, that is, their lower drought‐driven minimum values and higher post‐drought maximum values.Synthesis and applications. We show that communities in river ecosystems exposed to human impacts—in particular poor water quality, altered flow volumes and land use change—are particularly vulnerable to drought. These results provide evidence that management actions taken to enhance water quality, regulate abstraction and restore riparian land use could promote ecological resilience to drought in groundwater‐dominated rivers such as globally rare chalk streams and other rivers of the Anthropocene, as they adapt to a future characterized by increasing climatic extremity. [ABSTRACT FROM AUTHOR]

Large grazers modify vegetated ecosystems and are increasingly viewed as keystone species in trophic rewilding schemes. Yet, as their ecosystem influences are context‐dependent, a crucial challenge is identifying where grazers sustain, versus undermine, important ecosystem properties and their resilience.Previous work in diverse European saltmarshes found that, despite changing plant and invertebrate community structure, grazers do not suppress below‐ground properties, including soil organic carbon (SOC). We hypothesised that, in contrast, eastern US saltmarshes would be sensitive to large grazers as extensive areas are dominated by a single grass, Spartina alterniflora. We predicted that grazers would reduce above‐ and below‐ground Spartina biomass, suppress invertebrate densities, shift soil texture and ultimately reduce SOC concentration.We tested our hypotheses using a replicated 51‐month large grazer (horse) exclusion experiment in Georgia, coupled with observations of 14 long‐term grazed sites, spanning ~1000 km of the eastern US coast.Grazer exclusion quickly led to increased Spartina height, cover and flowering, and increased snail density. Changes in vegetation structure were reflected in modified soil texture (reduced sand, increased clay) and elevated root biomass, yet we found no response of SOC. Large grazer exclusion also reduced drought‐associated vegetation die‐off.We also observed vegetation shifts in sites along the eastern US seaboard where grazing has occurred for hundreds of years. Unlike in the exclusion experiment, long‐term grazing was associated with reduced SOC. A structural equation model implicated grazing by revealing reduced stem height as a key driver of reduced soil organic carbon.Synthesis: These results illustrate the context dependency of large grazer impacts on ecosystem properties in coastal wetlands. In contrast to well‐studied European marshes, eastern US marshes are dominated and structured by a single foundational grass species resulting in vegetation and soil properties being more sensitive to grazing. Coastal systems characterised by a single foundation species might be inherently vulnerable to large grazers and lack resilience in the face of other disturbances, underlining that frameworks to explain and predict large grazer impacts must account for geographic variation in ecosystem structure. [ABSTRACT FROM AUTHOR]

The sophisticated, modular and adaptable body plan of arthropods underpins their dominance in marine invertebrate communities. The origin of this body plan from legged lobopodian worms can be inferred from Cambrian Konservat‐Lagerstätten, but our understanding retains some notable gaps: not least in the transition from swimming lobopodians such as Kerygmachela and Pambdelurion to robustly sclerotized radiodonts such as Anomalocaris. A large Pambdelurion‐like fossil from the Xiaoshiba biota, Omnidens qiongqii sp. nov., exhibits a novel combination of characters: an oral apparatus with a non‐radial configuration; and centimetric talon‐like grasping structures with heavily sclerotized blade‐like spines. The novel morphology broadens the interpretative framework for associated Cambrian taxa, demonstrating continuity in the morphology of euarthropod appendages prior to the origin of podomeres. A reappraisal of the euarthropod stem lineage suggests that radially arranged mouthparts may be a radiodont novelty, rather than an inheritance from the ancestral ecdysozoan. These results further resolve the evolutionary origins of the euarthropod body plan. [ABSTRACT FROM AUTHOR]

Simplification of agricultural environments is linked to declines in biodiversity. Improving the floral diversity within and around these areas may result in more robust and diverse ecosystems. We investigated how floral resource abundance, diversity, and species composition in a cranberry agricultural system correlated to the abundance and overall invertebrate diversity and to the abundance and diversity of specific invertebrate groups of agricultural importance (e.g. parasitoids, phytophagous taxa, pollinators and predators). This study focused on habitats immediately surrounding cranberry production and included grassy dikes under a managed system (‘dike’), and semi‐natural areas growing on the surrounding support land (‘semi‐natural’). Floral resource availability and diversity tended to be similar between habitats, while invertebrate richness, diversity and composition differed. As the availability of floral resources increased, invertebrate abundance increased but diversity decreased. Overall invertebrate community composition differed with the specific species and availability of floral resources. The habitat type and floral resource composition impacted some agriculturally important groups, as pollinator abundance was higher in the semi‐natural habitat, and parasitoid abundance varied with floral resource composition across both habitats. These results suggest that managing the structural and floral resource diversity associated with agroecosystems can help support local biodiversity. However, these systems may disproportionately benefit more common taxonomic groups. The difference in responses of individual taxonomic groups also highlights the potential tradeoffs of focusing on only a subset of biodiversity aspects. [ABSTRACT FROM AUTHOR]

The widely observed negative scaling relationship between organism size and abundance is predicted to have a universal −0.75 scaling exponent across all life forms. However, factors influencing frequently observed deviations from this exponent, such as ecosystem succession and organism traits, remain poorly understood.We explore the dependence of size–density scaling on ecosystem succession and organism traits by analysing size–density relationships in trees and soil invertebrates across 183 temperate forest plots comprising urban secondary forests, urban old‐growth forests and non‐urban natural forests.Exponents of scaling relationships in urban tree and invertebrate communities progressively steepened with increasing restored (planted) forest stand age as small organisms increased in abundance. In contrast, non‐urban tree scaling relationships flattened during succession with exponents veering away from −0.75, whereas urban tree and invertebrate communities converged towards this prediction in later successional stages.Our results shed light on how the body size structure of tree and soil invertebrate communities spanning multiple trophic levels shift over successional time as the relative abundances of large versus small‐bodied organisms increase. This study emphasises the fundamental influence of organismal traits and ecosystem succession on scaling relationships of organism body size and abundance. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Molecular techniques like metabarcoding, while promising for exploring diversity of communities, are often impeded by the lack of reference DNA sequences available for taxonomic annotation. Our study explores the benefits of combining targeted DNA barcoding and morphological taxonomy to improve metabarcoding efficiency, using beach meiofauna as a case study. Beaches are globally important ecosystems and are inhabited by meiofauna, microscopic animals living in the interstitial space between the sand grains, which play a key role in coastal biodiversity and ecosystem dynamics. However, research on meiofauna faces challenges due to limited taxonomic expertise and sparse sampling. We generated 775 new cytochrome c oxidase I DNA barcodes from meiofauna specimens collected along the Netherlands' west coast and combined them with the NCBI GenBank database. We analysed alpha and beta diversity in 561 metabarcoding samples from 24 North Sea beaches, a region extensively studied for meiofauna, using both the enriched reference database and the NCBI database without the additional reference barcodes. Our results show a 2.5‐fold increase in sequence annotation and a doubling of species‐level Operational Taxonomic Units (OTUs) identification when annotating the metabarcoding data with the enhanced database. Additionally, our analyses revealed a bell‐shaped curve of OTU richness across the intertidal zone, aligning more closely with morphological analysis patterns, and more defined community dissimilarity patterns between supralittoral and intertidal sites. Our research highlights the importance of expanding molecular reference databases and combining morphological taxonomy with molecular techniques for biodiversity assessments, ultimately improving our understanding of coastal ecosystems. [ABSTRACT FROM AUTHOR]

Amphibians are among the most endangered taxa worldwide, but little is known about how their disappearance can alter the functioning and structure of freshwater ecosystems, where they live as larval stages. This is particularly true for urodeles, which often are key predators in these ecosystems. The fire salamander (Salamandra salamandra) is a common predator in European fresh waters, but the species is declining due to habitat loss and the infection by fungal pathogens. We studied the consequences of fire salamander loss from three montane streams, by comparing two key ecosystem processes (periphyton accrual and leaf litter decomposition) and the structure of three communities (periphytic algae, aquatic hyphomycetes and invertebrates) using stream enclosures with and without salamander larvae. Salamander loss did not cause changes in invertebrate abundance or community structure, except for one stream where abundance increased in the absence of salamander larvae. However, salamander loss led to lower periphyton accrual, changes in algal community structure and slower leaf litter decomposition, with no associated changes in fungal communities or microbial decomposition. The changes observed may have been caused by release of salamander predatory pressure on invertebrates, which could have promoted their grazing on periphyton, in contrast to their preference for leaf shredding in the presence of salamander. Our study demonstrates an important role of salamander larvae in montane streams through top‐down control of lower trophic levels and thus in regulating key stream ecosystem processes. Our results highlight the need for improving protection measures for amphibians to prevent these alterations on ecosystem structure and function. [ABSTRACT FROM AUTHOR]

Numerous and diverse groundwater habitats suitable for sustaining aquatic invertebrate communities exist across Australia. These habitats include enclosed subterranean aquifer systems, fractured rock, alluvial aquifers, perched aquifers, artesian springs, and spring-fed seeps and marshes. Crustaceans are a dominant member of these groundwater-associated invertebrate communities, and amphipods, both stygobiont and associated epigean species, are particularly diverse yet are still relatively poorly known. We review both the diversity and distributions of Australian amphipods associated with groundwater habitats, describing hotspots of diversity, providing notes on the unique Australian habitats, and examining the extraordinary species diversity and endemism of the Australian species. Our review highlights the significance of Australian groundwater ecosystems, their associated biodiversity, and the importance in considering these ecosystems in groundwater conservation management plans. [ABSTRACT FROM AUTHOR]

The physical effects of climate warming have been well documented, but the biological responses are far less well known, especially at the ecosystem level and at large (intercontinental) scales. Global warming over the next century is generally predicted to reduce food web complexity, but this is rarely tested empirically due to the dearth of studies isolating the effects of temperature on complex natural food webs. To overcome this obstacle, we used 'natural experiments' across 14 streams in Iceland and Russia, with natural warming of up to 20°C above the coldest stream in each high‐latitude region, where anthropogenic warming is predicted to be especially rapid. Using biomass‐weighted stable isotope data, we found that community isotopic divergence (a universal, taxon‐free measure of trophic diversity) was consistently lower in warmer streams. We also found a clear shift towards greater assimilation of autochthonous carbon, which was driven by increasing dominance of herbivores but without a concomitant increase in algal stocks. Overall, our results support the prediction that higher temperatures will simplify high‐latitude freshwater ecosystems and provide the first mechanistic glimpses of how warming alters energy transfer through food webs at intercontinental scales. [ABSTRACT FROM AUTHOR]

Simple Summary: The widespread use of broad-spectrum insecticides reduces the capabilities of ecological self-regulation of phytophages in agrocoenoses and in the adjacent natural territories. Those ecosystems suffer disruption of trophic relations that have been forming over long periods of time. At the same time, the numbers of non-target invertebrates affected by pesticides are declining. Pirimiphos-methyl is one of the cheapest, most effective, and widely used insecticides in the world. Its effect on invertebrate species is useful for agriculture; however, its effect on arthropods that improve soil fertility remains virtually unstudied. This article establishes that this insecticide can have a strong effect on some species useful for plant growing and a weak effect on others. As a result of such an effect of pirimiphos-methyl, the taxonomic structure of invertebrate communities in agrocenoses should change dramatically. The use of this insecticide in fields gives an advantage to species that are relatively more resistant to it and causes a faster disappearance of sensitive invertebrate species. The effects of pirimiphos-methyl have previously been assessed on blood-sucking insect species, pollinating insects, and target crop pest species. The sensitivity of non-target zoophagous and saprophage species to this insecticide remains largely unstudied. In laboratory conditions, we assessed the susceptibility of 43 species of invertebrates to pirimiphos-methyl. The most tolerant species to this insecticide were Pyrrhocoris apterus (LC50 measured over 60 mg/m2), Cylindroiulus truncorum, Pterostichus niger, Harpalus rufipes, Lithobius forficatus, and Carabus hortensis (LC50 ranged from 25 to 50 mg/m2). Average tolerance to pirimiphos-methyl was displayed by Ophonus rufibarbis, Teuchestes fossor, Silpha carinata, Badister sodalis, Rugilus rufipes, Phosphuga atrata, Porcellio laevis, Pterostichus oblongopunctatus, Aphodius foetens, Lasius fuliginosus, Oxypselaphus obscurus, Platydracus fulvipes, Myrmica ruginodis, Xantholinus tricolor, and Megaphyllum sp. (LC50 for those species ranged from 12 to 24 mg/m2). Higher sensitivity to this insecticide was seen for Amara nitida, Leistus ferrugineus, Harpalus xanthopus winkleri, Philonthus nitidus, Pterostichus melanarius, Harpalus latus, Limodromus assimilis, Philonthus decorus, Tachinus signatus, Ponera coarctata, Carabus convexus, Philonthus coprophilus, Philonthus laevicollis, Platydracus latebricola, Labia minor, and Carabus granulatus (LC50 for those species ranged from 6 to 12 mg/m2). The greatest sensitivity to pirimiphos-methyl was observed in Hister fenestus, Drusilla canaliculata, Bisnius fimetarius, Oxytelus sculptus, Lasius niger, and Lasius flavus (LC50 ranged from 0.4 to 6 mg/m2). We found a relationship between the parameters of bodies of invertebrates (the average body length and dry body mass) and sensitivity to pirimiphos-methyl. With an increase in body sizes of invertebrates, the tolerance to the insecticide increased (per each mm of body length, LC50 increased by 0.82 mg/m2 on average). We identified no relationship between the trophic specialization and sensitivity to the insecticide. [ABSTRACT FROM AUTHOR]

Coral reefs are among the most biodiverse ecosystems on Earth, largely due to the structural complexity created by corals. Coral habitat is crucial refuge for numerous small animals, and competition for habitat can structure populations if in short supply. Reefs in Hawai'i are largely dominated by the small branching coral Pocillopora meandrina, which supports diverse communities of fishes and invertebrates. Two species of nocturnal scorpionfishes, Sebastapistes coniorta and S. galactacma, are particularly common in P. meandrina, inhabiting the complex branching morphology of their host corals during the day and feeding in and around these corals at night. Surveys of scorpionfishes in 458 P. meandrina between 3 and 22 m deep along the south and west shores of O'ahu revealed inverse depth distributions over which these species occurred in P. meandrina. Sebastapistes coniorta almost exclusively occurred in coral colonies between 5 and 10 m deep, while S. galactacma were found across all depths surveyed, though were far more common and abundant in deeper coral colonies (15–20 m) below the range of S. coniorta. Further, measurements of host colony morphometrics revealed that these species appeared to use microhabitat in subtly different ways. The larger-bodied species, S. coniorta, was more commonly found in P. meandrina with wider spaces between branches, while the smaller-bodied species was negatively associated with wider branch spacing. These patterns indicate habitat partitioning between S. coniorta and S. galactacma at both the reef and colony scale, which may explain how these species are able to coexist on reefs in Hawai'i. [ABSTRACT FROM AUTHOR]

A variety of stormwater infrastructure such as constructed wetlands, rain gardens, vegetated drainage channels and retention ponds are primarily used for managing water runoff, but these environments can also foster biodiversity. Despite extensive literature about certain taxa (e.g., amphibians, aquatic macroinvertebrates, etc.) found in these human-made environments, the terrestrial plants and invertebrates present there remain understudied. Here, we compared alpha and beta diversity of plant and terrestrial invertebrate communities and assessed the influence of landscape characteristics on their composition in different types of urban stormwater basins and ponds. Plants and terrestrial invertebrates were identified in the main body (excluding the aquatic section) and on the banks of 54 basins and ponds (dry basins, wet basins with and without a water channel and retention ponds) in Quebec City and Trois-Rivières, in Eastern Canada. Results showed poor and homogenous plant and invertebrate communities in dry basins. Wet basins had the highest plant alpha diversity, with more facultative wetland species than the two other types. Wet basins with and without a water channel had similar plant and invertebrate composition, and wet basins and retention ponds were the most heterogeneous. Retention ponds (with permanent water) had distinct communities with fewer plant species than wet basins. The presence of natural areas around the infrastructure significantly influenced communities within a 2000 m and 500 m radius for plant and invertebrate communities, respectively. Wetland plant species were generally found in infrastructure close to natural areas, whereas tolerant and opportunist species were associated with disturbed environments. Our results suggest that enhancing diversity of the stormwater basins and ponds at the regional and local (microhabitat) scales has the potential to maximize diversity of plants and terrestrial invertebrates. [ABSTRACT FROM AUTHOR]

Aquatic invertebrate community composition was sampled over 10 months in ephemeral and permanent pools along the upper segment of an ephemeral stream in Central Texas. A total of 67 total taxa were documented during this study. The highest numbers of taxa by total count found during the study were Hyalella, Chironomidae, Physa, and Caenis with total counts ranging from 1957 to 7437 individuals. Taxa with total moderate counts ranging between 209 and 856 individuals were Oligochaeta, Helobdella, Corbicula, Cyclopoida, Planorbis, and Berosus. Twelve different functional feeding groups were observed with collector-gathers-shredder accounting for 29.1%. The Pollution Tolerance Level was highest from 6 to 9 and peaked at 8 for both permanent and ephemeral pools indicating poor water quality. Based on the Hilsenhoff Family Biotic Index (FBI), the FBI was estimated to 7.47 and 7.53 for permanent and ephemeral pools, respectively, indicating poor water quality high in organic matter. Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa were represented by 5.3 and 18.2% of the total counts in permanent and ephemeral pools, respectively. All other taxa, excluding EPT taxa, represented 94.7 and 81.8% of the total counts in permanent and ephemeral pools, respectively. Our results indicate the runoff from adjacent urban areas resulted in reduced water quality within the pools based on aquatic invertebrate taxa. With reduced protection of ephemeral streams under the 2023 Supreme Court WOTUS decision, water quality and biodiversity will continue to decline and impact perennial river water quality longitudinally during flow events. [ABSTRACT FROM AUTHOR]

Estuaries support diverse fish and invertebrate communities, including resident species that rely on estuarine habitats year‐round and transient migratory species. The unique movement patterns of these animals connect habitats within and far beyond the estuary and are integrally linked to fisheries management objectives. With a focus on Chesapeake Bay, this study leveraged data from collaborative acoustic telemetry networks in the northwest Atlantic to assess habitat use and phenology of movements for seven species of fish (cownose rays, dusky sharks, smooth dogfish, alewife, striped bass, common carp, and blue catfish) and one invertebrate (horseshoe crabs). A total of 288 acoustically tagged individuals were detected >3.2 million times (6,743 to 2,095,717 detections per species) on receivers across ~20.5 degrees of latitude spanning the North American Atlantic seaboard from Florida, USA, to New Brunswick, Canada. Common metrics of movement and phenology grouped these species as resident (common carp, blue catfish, horseshoe crabs), primarily resident in estuaries (juvenile striped bass), and coastal migrant (cownose rays, dusky sharks, smooth dogfish, alewife); maximum distance traveled varied by three orders of magnitude among these species. Further analysis of phenology for coastal migrants elucidated the timing and duration of these species' use of Chesapeake Bay. Collectively, movements linked habitats within Chesapeake Bay and connected the estuary to coastal ecosystems both to the north (e.g., alewife) and south (e.g., cownose rays), creating networks of fisheries management jurisdictions that varied in complexity and identified opportunities for enhancement to current management or co‐management of some species. Our results elucidate the importance of estuaries to species with diverse movement behaviors, identify scales and pathways of habitat connectivity via animal movements, and highlight the utility of collaborative acoustic telemetry networks for quantifying movements relevant to both ecological research and fisheries management. [ABSTRACT FROM AUTHOR]

Alarm calls produced by basal prey have a well-known informative value. In multi-predator communities, mesopredators, when faced with top predators, may emit alarm calls that could inform basal prey about their lowered predation risk. To test this unexplored possibility, we conducted one field and one mesocosm experiment in which we simulated alarm and non-alarm calls from little owls (Athene noctua) as mesopredators and measured their effects on grasshoppers as prey of little owls but not of top predators. In the field experiment, we found that grasshopper species were significantly more abundant in patches where we simulated either the presence of scared little owls (alarm treatment) or no owls (control treatment) compared to patches where the presence of non-scared little owls (non-alarm treatment) was simulated. In the mesocosm experiment, locusts (Locusta migratoria) moved significantly more to exposed areas when we simulated the presence of scared little owls (alarm treatment) or of a granivorous bird (control treatment), while they moved to sheltered areas when we simulated the presence of non-scared owls (non-alarm treatment). These results show that prey could cue on predators' calls to assess their predation risk and make decisions, revealing unprecedented potential ecological consequences of alarm calls in invertebrate communities. [ABSTRACT FROM AUTHOR]

Marine birds and pinnipeds which come to land to breed, rest and moult are widely known to fertilize adjacent terrestrial ecosystems, with cascading effects on vegetation and other trophic levels. We provide a synthesis of the consequences of allochthonous nutrient enrichment for terrestrial invertebrate communities within and around marine vertebrate aggregation sites and nutrient sources in the High Arctic and Continental and Maritime Antarctic, the most nutrient-poor and environmentally extreme parts of the polar regions. Using a combination of literature review (identifying 19 articles from the Arctic Svalbard archipelago and 12 from different Antarctic locations) and new analyses of available datasets of springtail, mite and tardigrade community composition, we confirmed that terrestrial invertebrate abundance and species richness tended to increase, and their community compositions changed, as a result of marine vertebrate fertilisation in both polar regions. These changes were significantly greater on talus slopes enriched by kittiwakes, guillemots and little auks in the Arctic, as compared to the edges of penguin colonies in the Antarctic. Both these habitat areas were typically abundantly vegetated and provided the most favourable microhabitat conditions for terrestrial invertebrates. The most heavily disturbed and manured areas within Antarctic penguin rookeries and seal wallows, generally on flat or gently sloping ground, were typically characterised by extremely low invertebrate diversity. In the Arctic, only sites directly beneath densely-occupied bird cliffs were to some extent comparably barren. Invertebrate responses are dependent on a combination of vertebrate activity, local topography and vegetation development. [ABSTRACT FROM AUTHOR]

Aquatic macrophytes serve as shelter and a direct source of food for invertebrates, in addition to indirectly providing items such as algae, detritus, and microorganisms. Thus, aquatic macrophytes act as habitat structuring elements, requiring a distinction between habitat complexity (physical formations such as fractal dimensions, density and biomass) and habitat heterogeneity (diversity of these structures). Here we explore the effects of habitat complexity and habitat heterogeneity on the invertebrate community.We collected macrophytes and invertebrates from 28 sampling sites along a 13.7‐km stretch of the Baía River in Brazil, and examined specific groups (insects, microcrustaceans, and other invertebrates). Environmental variables in the sites were also measured. We aimed to explore the effects of habitat complexity (measured by macrophyte biomass) and habitat heterogeneity (evaluated through macrophyte functional diversity) on the richness and abundance of invertebrates.We found that overall invertebrate richness was positively influenced solely by habitat heterogeneity. For invertebrate abundance, intermediate habitat complexity had more invertebrates, while habitat heterogeneity had a positive impact. Environmental variables influenced only the abundance. For specific groups, insect richness was positively influenced by habitat heterogeneity, while insect abundance decreased with high complexity and increased with high heterogeneity. Microcrustacean abundance was positively influenced by habitat complexity. Richness and abundance of other invertebrates was positively influenced by habitat heterogeneity.Invertebrates prefer macrophyte stands with intermediate complexity and high heterogeneity. Abundance is linked to structural complexity and heterogeneity, while species richness is more strongly associated with heterogeneity. Furthermore, the impact of these factors varies among invertebrate groups.These findings emphasise the importance of integrating a broad range of metrics, such as macrophyte biomass and functional diversity, to gain a thorough understanding of invertebrate community dynamics in future studies. Additionally, our study demonstrates that preserving macrophyte stands with high heterogeneity significantly enhances the diversity of associated invertebrate species. [ABSTRACT FROM AUTHOR]

Anthropogenic biodiversity loss can impair ecosystem functioning. Human activities are often managed with the aim of reversing biodiversity loss and its associated functional impacts. However, it is currently unknown whether biodiversity–ecosystem function (BEF) relationships observed during biodiversity recovery are the same as those observed during biodiversity loss. This will depend on how species extirpation and recolonisation sequences compare and how different species influence ecosystem functioning. Using data from a marine benthic invertebrate community, we modelled how bioturbation potential – a proxy for benthic ecosystem functioning – changes along biodiversity loss and recovery sequences governed by species' sensitivity to physical disturbance and recolonisation capability, respectively. BEF relationships for biodiversity loss and recovery were largely the same despite species extirpation and recolonisation sequences being different. This held true irrespective of whether populations were assumed to exhibit compensatory responses as species were removed or added. These findings suggest that the functional consequences of local biodiversity loss can be reversed by alleviating its drivers, as different species present at comparable levels of species richness during biodiversity loss and recovery phases have similar functional effects. Empirically verifying and determining the generality of our model‐based results are potential next steps for future research. [ABSTRACT FROM AUTHOR]

Restoring and monitoring soil biodiversity has never been more important. Ecoacoustics is emerging as a promising tool to detect and monitor soil biodiversity and was recently effective in a temperate forest context. However, there is a need to investigate the efficacy of soil ecoacoustics in other ecosystems and bioregions.Here, we applied ecoacoustics tools and indices (Acoustic Complexity Index, Bioacoustic Index, Normalised Difference Soundscape Index) to measure soil biodiversity in an Australian grassy woodland restoration chronosequence, spanning three age classes. We collected n = 240 soil acoustic samples from two cleared plots (continuously cleared through active management), two woodland plots undergoing restoration (revegetated 14–15 years ago) and two plots of remnant vegetation over 5 days in Mount Bold, South Australia. We used a below‐ground sampling device and sound attenuation chamber to record soil invertebrate communities, which were also manually counted.We found that acoustic complexity and diversity were significantly higher in revegetated and remnant plots than in cleared plots, both in‐situ and in sound attenuation chambers. The acoustic complexity and diversity also significantly associated with soil invertebrate abundance and richness.Synthesis and applications. Our results provide new support that ecoacoustics can help monitor soil biodiversity in different forest restoration contexts, including in UK temperate and Australian grassy woodlands. This technology holds promise in addressing the global need for effective soil biodiversity monitoring methods and protecting our planet's most diverse ecosystems. [ABSTRACT FROM AUTHOR]

Geographic isolation is a factor that is known to affect species composition and diversity in marine systems. In this study, we tested the effects of geographic isolation on invertebrate fauna living among the belt-forming foundation species Fucus vesiculosus in the northern Baltic Sea. Sampling was carried out on reefs with varying levels of isolation (0.5, 1 and 2 km) in July 2021 in the Åland islands (between 59.96°N 20.24°E and 59.75°N 20.84°E). The total number of taxa, abundance, Shannon-Wiener index, Pielou's evenness and biomass were calculated and the effects of isolation were tested using generalised linear models. Multivariate methods were used to analyse differences in the invertebrate community composition. Although the number of taxa and Shannon´s diversity index did not vary along the isolation gradient, the total abundance of fauna decreased with increasing isolation. In addition, some taxa-specific patterns were observed, e.g. the abundance of insect larvae decreased with isolation while isopods were more numerous in the most isolated locations. As diversity and the number of taxa were similar regardless of isolation, shallow Fucus vesiculosus belts likely act as important biodiversity refuges and potential stepping-stones for invertebrates in remote outer archipelago areas. In a changing climate, these kinds of refuges aiding species dispersal are likely to be even more important, and should be considered in conservation planning. [ABSTRACT FROM AUTHOR]