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The document "Thanks to Reviewers" from the journal Criminal Justice & Behavior acknowledges and appreciates the numerous individuals who reviewed manuscripts in 2024. The list includes a diverse range of names from various backgrounds and expertise, showcasing the collaborative effort in the field of criminal justice. This comprehensive list reflects the dedication and commitment of reviewers to ensure the quality and integrity of research in the discipline. [Extracted from the article]

The positive relationship between biodiversity and beaver‐modified habitats such as ponds, dams, and canals has been demonstrated; however, the association between biodiversity and beaver lodges is rarely investigated. Due to increasing habitat fragmentation, there is a growing need to identify local biodiversity hotspots.This systematic review assessed current scientific knowledge concerning the association between beaver lodges and biodiversity. Specifically, the study aimed to 1) investigate the evidence for beaver lodges being local biodiversity hotspots; 2) identify areas of future research centred around the relationship between biodiversity and beaver lodges; and 3) provide recommendations on how to monitor the relationship between biodiversity and beaver lodges within the UK.Through a stepwise process of database searching and literature sorting, a final dataset of 35 articles emerged, with each article including at least one species, besides beavers, interacting with beaver lodges.Analysis of the final dataset of articles showed beaver lodges offer multiple uses and fitness benefits for several species in highly seasonal environments, with daily and seasonal visitor variation influenced by intraspecific and interspecific interactions. Beaver lodges were shown to have higher species richness and diversity compared to microhabitats in the surrounding areas, supporting the concept of beaver lodges being local biodiversity hotspots.We recommend that future studies use videographic methodology to monitor beaver lodges and other treatment groups in the surrounding area. Using the described methodology, beaver management plans should monitor beaver lodges across the northern hemisphere, helping to further understand these important local biodiversity hotspots. [ABSTRACT FROM AUTHOR]

In 1946, 20 beavers (Castor canadensis) were introduced in Tierra del Fuego, Argentina, and over the last 70 years, the population has expanded, severely affecting riparian environments. In 2008, Argentina and Chile agreed to restore the environments affected by beavers through their eradication. The objectives of this paper were to assess the trapping effort and cost required to remove beavers, and to determine the factors that influence capture success. The study was conducted over 7 pilot areas in the Argentine part of Tierra del Fuego. Ten trappers using body‐grip traps, snares, and shooting carried out an eradication pilot project between October 2015 and June 2018. Trappers acted in 505 colonies, performing 9,751 trapping episodes, and capturing 1,012 beavers. In the mountain range zone, trappers needed on average 23 trapping episodes/km of watercourse. Capture success was best explained by trap placement and trap type. We estimated a required investment of 31 million US dollars over 17 years for a full beaver eradication in the Argentine part of Tierra del Fuego. We concluded that by using mainly body‐grip traps, eradication is feasible and it allows trapping in neighboring colonies simultaneously, without the need to check traps daily. Traps should be set preferably on dams, dams should be broken only after the first captures, and trappers should be trained to capture all individuals. [ABSTRACT FROM AUTHOR]

There is growing interest in working with beavers (Castor canadensis and Castor fiber) to restore and maintain ecosystem function, improve hydrologic conditions and build climate resiliency in freshwater ecosystems. Beaver translocation into historically occupied but degraded systems has been increasingly applied as a restoration practice over the last two decades. Knowledge of beaver distributions on the landscape is critical to understanding where and when beaver translocations may be effective. However, current understanding of beaver occupancy and translocation success is limited by uncertainty, subjectivity and inefficiency associated with available monitoring methods. We evaluated the efficacy and spatial inference associated with environmental DNA (eDNA) techniques for detecting beaver presence in natural wetland and stream systems in the Cascade mountains of Washington State. We conducted eDNA sampling paired with radio‐tracking of translocated beavers at four relocation sites from October 2020 through October 2022 to elucidate spatial patterns of site use, eDNA detection probability and eDNA quantity. We found that eDNA techniques detected beaver rapidly over long distances – up to 2.9 km from known locations within the first week after release – and reliably detected beavers when they were upstream, with positive detections in 92.4% of downstream eDNA samples collected 1–3 months after release. We also found that eDNA quantity decreased with increasing distance from beaver and increased with the amount of upstream beaver activity. Our study suggests that eDNA is a sensitive tool for monitoring translocated beaver and can provide spatial information on beaver location and site use within a stream system. Hence, eDNA methods could be a valuable tool for rapid inventory and assessment of beaver occupancy and our findings highlight important implications for using eDNA to monitor other semi‐aquatic mammal species that share similar life histories. [ABSTRACT FROM AUTHOR]

Beavers are semi-aquatic rodents that are considered to be pests by humans due to their habit of building dams and the damage they cause to their surrounding ecosystems. Using a program known as NaxEnt, which is a statistical package that can determine the probabilities of species distributions based on surrounding environmental information, we analyzed both nusiance reports of beavers as well as crowdsourced information to create a habitat suitability model. It appears that beavers were most strongly associated with the land cover types of Powerlines/Utility, Non-Forested Wetland, Water-based Recreation, Cropland, and Open Land. Nuisance beavers are negatively correlated with human population density, while iNaturalist beavers were positively correlated. It appears that these models and the workflow for creating them has developed into a suitable base for future research, while also showing the effect that public participation can have on data.

Urban beaver and stormwater ponds provide hydrologic retention in the landscape while collecting dissolved organic matter (DOM)-rich runoff that can promote primary productivity. Our objective was to determine how the quantity, source, and bioavailability of DOM changed across urban stormwater and beaver pond systems, then compare the two pond types to each other. We measured dissolved organic carbon (DOC) and specific ultraviolet absorbance at 254 nm (SUVA254) from upstream, within, and downstream of seven ponds in Atlanta, GA, USA, biweekly from March to December 2021. Additionally, we completed 28-day laboratory microcosm incubations of pond in- and out-flow during summer and autumn of 2021. We found higher concentrations of DOC in the pond and outflows of stormwater ponds, whereas beaver ponds did not cause any change. Effects of pond type (beaver vs. stormwater) were greater than other controls on concentration, including flow and season. In contrast, SUVA254 showed a shift toward more aromatic carbon below both systems without a clear difference between pond types. Beaver and stormwater pond outflows had similar ranges of DOM bioavailability in summer, but during autumn bioavailability at both sites declined to near zero. Overall, we found that stormwater ponds and beaver ponds had similar impacts on aromaticity and bioavailability, however stormwater ponds increased the quantity of DOC while beaver ponds did not. This suggests that in addition to increasing hydrologic residence times in urbanized systems, urban beaver ponds may limit the export of bioavailable carbon and reduce microbial processing downstream. [ABSTRACT FROM AUTHOR]

Beavers modify riverine systems by building dams that alter downstream fluxes of water and sediment. Where beavers have been lost and stream channels degraded, beaver dam analogs (BDAs) are being used to mimic the effects of beaver engineering. Central to the success of these structures in accelerating stream recovery is creating similar ecosystem responses as beaver dams including sediment retention. Unknown is the relative importance of beaver actions versus erosion in the catchment in generating the retained sediment. This study tested the viability of sediment fingerprinting to determine the source of sediment retained by beaver dams and BDAs in a watershed in Alberta, Canada. Concentrations of 29 elements were measured as potential tracers from known sediment sources: upland, terrace, stream bank, and beaver canal. Virtual mixture tests, used to compare the computed source estimates with known source mixtures, revealed that sediment fingerprinting is a robust method for identifying sources of sediment retained by beaver ponds and BDAs. The un‐mixing model results indicate that on average 56% of the sediment retained by the beaver dams originated from terraces, 23% from uplands, and 13% from beaver canals. About 89% of sediment retained by the BDAs originated from eroding stream banks. We conclude that the geomorphic effects of beavers and their dams are more diverse, resulting in more diverse sources of sediment retained by their dams. This differentiates beaver dams from BDAs. The study has implications for informing management practices that involve beavers and beaver mimicry. Plain Language Summary: Growing recognition of the importance of beaver dams in maintaining naturally functioning streams and floodplains has spurred the use of beaver mimicry structures to accelerate stream recovery where stream channels have cut downward because beavers are absent. Despite the importance of sediment trapping in determining the success of beaver mimicry structures in raising the stream bed, the source of the trapped sediment is poorly known and seldom analyzed. This study investigated whether sediment fingerprinting, a well‐known method for assessing sources of lake, estuary and floodplain sediment deposits, could reliably establish the sources of sediment retained by beaver dams and beaver mimicry structures. We tested this method in a watershed in the Canadian Rocky Mountains and found that it effectively differentiated between the sources of sediment trapped by beaver dams and beaver mimicry structures. Sediment trapped by the mimicry structures originated mainly from stream banks flooded by the structures, whereas beaver dams trapped sediment originating from a combination of riparian areas, canals dug by beavers and hillslopes. Beaver mimicry structures did not replicate the sediment trapping processes of beaver dams because the beavers were important in actively mobilizing the sediment that became trapped by their dams. Key Points: Sediment fingerprinting can effectively establish the source of sediment retained by beaver dams and beaver dam analogs (BDAs)Sediment retained by beaver dams originates from different and more diverse sources than sediment retained by BDAsBDA sediment composition does not replicate that of beaver dams as beavers contribute sediment via canal building and terrace inundation [ABSTRACT FROM AUTHOR]

Since the last century, the aquatic ecosystems of Tierra del Fuego have been impacted by the introduction of exotic species, among which the North American beaver Castor canadensis and salmonids stand out for their dispersion and abundance. This study is part of the project Strengthening Governance for the Protection of Biodiversity Through the Formulation and Implementation of the National Strategy on Invasive Alien Species, for the eradication of C. canadensis from the Isla Grande de Tierra del Fuego (IGTdF). This work aimed to evaluate the effect of beaver plantation removal on different aspects of the ichthyofauna of the IGTdF. Ichthyological sampling was carried out before and after the beaver ponds in six sites spread across the island. Three species of salmonids (Salmo trutta, Oncorhynchus mykiss and Salvelinus fontinalis) were captured, and an average increase of 43% in their abundance, changes in their diet, and differences in their energy density (higher or lower depending on the species) was observed after the removal of the beaver ponds. No native fish species were recorded before or after the removal of the beaver pond. The results suggest that the beaver ponds impact positively salmonid populations. [ABSTRACT FROM AUTHOR]

For fractured gas reservoirs with strong water drive, gas phase trapping affects the gas recovery significantly. The recovery may be less than 50% for some reservoirs while it is only 12% for Beaver River gas field. The gas phase trapping mechanism has been revealed by the results of depletion experimental test. The residual pressure of the trapped gas is as high as 11.75 MPa with a 12.8 cm imbibition layer resulting in gas recovery deceased 49.5% compared with that without imbibition layer. A mathematical model is built to calculate the imbibition thickness based on capillary pressure and relative permeability of the matrix. The gas phase trapping are analyzed by two representative wells in Weiyuan gas field, the intermittent production reinforces the imbibition thickness and result in gas trapped in the matrix block with high residual pressure for the low performace gas wells, the extremely low gas recovery can be explained more rationally. That lays a foundation of improving the gas recovery for fractured reservoirs. [ABSTRACT FROM AUTHOR]

Freshwater habitats support high levels of biodiversity and provide important habitat for wetland‐dependent taxa; however, impairment of aquatic connectivity through wetland loss, stream alterations and light pollution impacts species persistence and community resilience. Quantifying occupancy of these habitats to assess their use by mammals and birds can be challenging, especially for cryptic species.This study examines wetland habitat use by mammals and birds, and their spatial and temporal relationships within the Beaver Hills Biosphere in Alberta, Canada. As part of a multi‐method detection approach, camera boxes, cameras on beaver dams, and camera rafts allowed for multivariate analyses to determine temporal and spatial patterns of habitat use and species associations, while field sampling and environmental DNA (eDNA) provided data on site occupancy by a subset of semi‐aquatic mammals.From ~50,000 images, over 84 species were detected, including 52 species of birds and 25 species of mammals. Several species were spatially associated, and although most species of mammals exhibited temporal overlap, there were distinct differences, especially on beaver dams where predators such as coyotes and white‐tailed deer shared the same space. Temporally, birds were detected most often during the day and mammals at night. During new moon phases, use of beaver dams by beavers decreased dramatically, and use of camera rafts by muskrats increased.Winter field surveys allowed for a broad overview of wetland occupancy and abundance of some species, particularly by beavers and muskrats, and occasionally winter use by other semi‐aquatic mammals. Where there was limited detection of more cryptic species of semi‐aquatic mammals, eDNA analysis successfully detected American water shrew, American mink, North American river otter and northern bog lemming more often than camera and field methods.Applying a multi‐method monitoring approach for mammals and birds in wetland habitats is critical at a time when freshwater systems are experiencing dramatic declines in relative abundance of monitored wildlife populations, with many of these species underrepresented in conventional surveys. [ABSTRACT FROM AUTHOR]

The maintenance and restoration of wetland habitat is a priority conservation action for most waterfowl and other wetland-dependent species in North America. Despite much progress in targeting habitat management in staging and wintering areas, methods to identify and target high-quality breeding habitats that result in the greatest potential for wildlife are still required. This is particularly true for species that breed in remote, inaccessible areas such as the American black duck, an intensively managed game bird in Eastern North America. Although evidence suggests that black ducks prefer productive, nutrient-rich waterbodies, such as beaver ponds, information about the distribution and quality of these habitats across the vast boreal forest is lacking with accurate identification remaining a challenge. Continuing advancements in remote sensing technologies that provide spatially extensive and temporally repeated information are particularly useful in meeting this information gap. In this study, we used multi-source remotely sensed information and a fuzzy analytical hierarchy process to map the spatial distribution of beaver ponds in Ontario. The use of multi-source data, including a Digital Elevation Model, a Sentinel-2 Multi-Spectral Image, and RadarSat 2 Polarimetric data, enabled us to identify individual beaver ponds on the landscape. Our model correctly identified an average of 83.0% of the known beaver dams and 72.5% of the known beaver ponds based on validation with an independent dataset. This study demonstrates that remote sensing is an effective approach for identifying beaver-modified wetland features and can be applied to map these and other wetland habitat features of interest across large spatial extents. Furthermore, the systematic acquisition strategy of the remote sensors employed is well suited for monitoring changes in wetland conditions that affect the availability of habitats important to waterfowl and other wildlife. [ABSTRACT FROM AUTHOR]

In Flanders, beavers have reappeared since 2000 and their numbers have expanded rapidly over the last decade, challenging impact management. To help identify areas with increased vulnerability to beaver damage we developed a species distribution model (SDM). In this model, we combined a MaxEnt-based approach to estimate habitat suitability and potential future spread with simulated dispersal using the SiMRiv R-package. We constructed our model in 2020 based on 2019 distribution data of beavers in Flanders and used it to predict population distribution probability up to 2022. To validate the combined model output, we compared the results for each 1 km² grid cell to the observed distribution of beavers in Flanders in 2020–2022. Our model predicted possible beaver occupancy in 4,361 out of 14,343 1 km² grid cells in Flanders. In 51.4% of these grid cells predicted probability of occupancy was accidental, in 29.3% it was low, in 13.0% medium and in 6.4% high. In 2020–2022 beavers were observed in 908 1 km² grid cells in Flanders. Comparison with the model output showed that the model performed well overall (AUC 0.825), although the negative predictive power was much higher than the positive predictive power since the model tends to overestimate actual occupancy over this three-year period. However, the accuracy rises with the projected level of occupancy probability. Although the overestimation fits the intended risk management purposes of the model, expanding it beyond the borders of Flanders and strengthening the backbone of the model with a more detailed population model could further improve the output and help improve the positive predictive power. [ABSTRACT FROM AUTHOR]

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The range of keystone species is increasing in some parts of the world, particularly Europe, through a combination of natural recolonization, government‐sanctioned and covert reintroductions. Reintroductions are an important conservation tool, particularly in the increasingly popular approach of rewilding.There is relatively little understanding of the politics, broadly conceived, of species reintroduction, particularly around how people who live alongside these newly introduced species might react, and what underpins this reaction, and how the method of reintroduction affects reactions.Here, we explore these issues through a case of beavers in central Scotland, which were covertly reintroduced. We explore opposition to reintroduction as manifest in beaver killing and dam destruction by land managers, quantifying these using the sensitive 'bean count' method.We also explore what underpins land managers' reactions, particularly their views and values around land and land management.We found considerable resistance. We found that beaver killing and dam destruction were widespread, both before and after beavers became a protected species. Nevertheless, beaver populations and ranges in Scotland continue to grow.We found attitudes were grounded in a strong set of relational values around land custodianship. We find a range of views towards beavers, including widespread opposition, particularly regarding the covert nature of beaver introduction, the challenge beavers and beaver protection provide to ideas of proper land management and custodianship, and a lack of trust in formal methods of beaver governance.We argue that species reintroductions policies and research should give careful consideration to potential opposition, its material impacts on reintroduction projects and how it is grounded in wider environmental values and politics. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

This article discusses the use of customizable PCR-based target enrichment probes for sequencing fungi-parasitized insects. The authors emphasize the importance of understanding the systematics of both insect hosts and their fungal parasites in order to study insect-fungal symbioses. They propose the use of PCR-based enrichment probes as a flexible and effective solution for extracting host DNA in these symbiotic complexes. The authors provide a protocol and present results from their study, demonstrating the feasibility and applicability of this approach. They also highlight the potential of PCR-based enrichment probes for studying other insect-parasite coevolution and systematics. The article concludes by discussing the scientific equity and community participation that can be achieved through customizable PCR-based enrichment probes, allowing local scientists to devise their own sequencing strategies without relying on commercial probe sets. The document includes acknowledgments, disclosures, data availability statements, and references related to the study, as well as supplementary files with protocols for genomic library preparation, probe preparation, hybridization, and PCR amplification. [Extracted from the article]

Scientists and policy‐makers promote 'Nature‐based Solutions' to the interconnected challenges associated with the Anthropocene. Often these involve the strategic use of ecosystem engineers: animals, plants, and microbes with disproportionate ecological agency capable of regional or even planetary‐scale niche construction. This environmental mode of biopolitics is promoted as biomimicry: restoring, rewilding, or rewetting diverse ecological systems. This paper critically examines the multispecies relations promised by this model through a focus on beaver in Britain over the last 12,000 years. It begins with beaver making Britain hospitable for early settlers and agriculturalists as they returned after the last ice age. It traces the subsequent demise of beaver due to hunting and land use change, and then follows the recent return of beaver as tools for natural flood management and nature recovery. It attends to situations in which these multispecies world‐making projects go awry in the weird ecologies of the Anthropocene. This story of beaver helps situate enthusiasms for proactive ecosystem engineering in deeper time. It highlights the beguiling potential of Nature‐based Solutions while cautioning against tendencies towards anthropocentrism, an apolitical mononaturalism, and an ecomodernist hubris. The paper combines concepts from archaeology, ecology, anthropology, and geography into a new framework for theorising multispecies acts of worlding and weirding. [ABSTRACT FROM AUTHOR]

The article focuses on the shared motif of enslaved beavers in medieval literature across diverse cultures. Topics include the depiction of hierarchical beaver societies in Northern European and Arabic sources, the role of enslaved beavers in carrying wood, and the story's potential origins and spread between cultures. It examines how this motif illustrates the movement of folklore and reflects on the broader implications of the story's global dissemination.

In this study, we describe the dental remains of a very minute beaver from the early Late Miocene locality Hammerschmiede (MN 7/8) located at the Northern Alpine Foreland Basin (Southern Germany, Bavaria). The finds represent the so far most comprehensive (>1.000 dental specimens) collection of the trogontheriine castorid Euroxenomys minutus. Metrically and morphologically, the large data set demonstrates an extensive intraspecific variability of this beaver from Hammerschmiede that covers most finds of other European localities and confirms previous species assignments. The subspecies Euroxenomys minutus rhenanus from Dorn-Dürkheim (Germany), clearly isolates from this range of variation and can thus be validated. The performed age-frequency distributions for Euroxenomys minutus from the local stratigraphic levels HAM 5 (rivulet) and HAM 4 (river) correspond roughly and also resemble Euroxenomys from the swamp deposit Rudabánya (Hungary). Since previous mortality studies on the also occurring larger beaver Steneofiber depereti from Hammerschmiede demonstrated dominance of behavioural or internal factors, this cross-ecosystem similarity in mortality for the small beaver species is likely explained by external factors, such as predation. Supported by a taphonomic bone analysis, a multitude of predators are finally considered to prey on Euroxenomys minutus and indicate a predatory bone assemblage. [ABSTRACT FROM AUTHOR]

"For I pray God for the ostriches of Salisbury Plain, the beavers of the Medway and silver fish of Thames" (Jubilate Agno , B153): species extinction in Christopher Smart's unique poem is the focal point of this essay. That the poem's ecstatic scope offers a leveling care for the nonhuman has been acknowledged, but here I argue that it speaks out of abjection: the poet is the supplicant, asking all Earth's creatures to advocate for him before God. Additionally, focusing particularly on the figure of the beaver, I highlight the medieval animal fable as a valid mode of understanding better our animal kin today. [ABSTRACT FROM AUTHOR]

Microbial source tracking leverages a wide range of approaches designed to trace the origins of fecal contamination in aquatic environments. Although source tracking methods are typically employed within the laboratory setting, computational techniques can be leveraged to advance microbial source tracking methodology. Herein, we present a logic regression-based supervised learning approach for the discovery of source-informative genetic markers within intergenic regions across the Escherichia coli genome that can be used for source tracking. With just single intergenic loci, logic regression was able to identify highly source-specific (i.e., exceeding 97.00%) biomarkers for a wide range of host and niche sources, with sensitivities reaching as high as 30.00%-50.00% for certain source categories, including pig, sheep, mouse, and wastewater, depending on the specific intergenic locus analyzed. Restricting the source range to reflect the most prominent zoonotic sources of E. coli transmission (i.e., bovine, chicken, human, and pig) allowed for the generation of informative biomarkers for all host categories, with specificities of at least 90.00% and sensitivities between 12.50% and 70.00%, using the sequence data from key intergenic regions, including emrKY-evgAS, ibsB-(mdtABCD-baeSR), ompC-rcsDB, and yedS-yedR, that appear to be involved in antibiotic resistance. Remarkably, we were able to use this approach to classify 48 out of 113 river water E. coli isolates collected in Northwestern Sweden as either beaver, human, or reindeer in origin with a high degree of consensus--thus highlighting the potential of logic regression modeling as a novel approach for augmenting current source tracking efforts. [ABSTRACT FROM AUTHOR]

In mountainous watersheds, floodplain sediments are typically characterized by gravel bed layers capped by an overlying soil unit that serves as a hotspot for biogeochemical reactivity. However, the influence of soil biogeochemistry on gravel bed underflow composition remains unclear, especially during hydrological transitions that alter the vertical connectivity between overlaying soils and the underlying gravel bed. This study investigates these dynamics by measuring hydraulic gradients and water compositions over three hydrological years in a typical mountainous, low‐order stream floodplain in the Upper Colorado River Basin. Results indicate that the timing of hydrological conditions strongly influences the vertical exchanges that control water quality. Specifically, during flooding events such as beaver ponding, that induce downward flushing of the soil, anoxic conditions prevalent in the biogeochemically active soil are transferred downstream via gravel bed underflow. Conversely, snowmelt and drought conditions increase oxic conditions in the gravel bed due to diminished hydrological connectivity with the overlying soil. To compare water quality response to hydrological transitions across similar floodplain environments, we propose a conceptual model that quantifies the inundation‐induced flushing of soil porewater to measure solute exchange efficiency with the gravel bed solute convergence efficiency (SCE). This model provides a framework for quantifying biogeochemical processes in hydrological underflow systems, which is critical for water and elemental budgets in these globally important mountainous ecosystems. Plain Language Summary: Mountains are important sources of freshwater for humans and ecosystems. They are however increasingly impacted by climate change. In this paper, we investigate how changes in water availability (droughts, snowmelt, inundations) can cascade into changes in water quality (concentrations of dissolved chemical elements). We show that in mountain valleys, the zone of contact between the soil and the underlying gravel bed aquifer is important for water quality. Chemical elements from the soil can be flushed down into the gravel bed aquifer, then transported by groundwater to the stream. Chemical elements from the soil can also react with chemical elements present in the aquifer. Our research can be used to better predict the water and elemental budgets in these important mountainous systems. Key Points: Soil / gravel bed connectivity in floodplains is important for water qualitySnowmelt and drought both reduce soil / gravel bed connectivityBeaver ponding increases downward flushing to gravel bed unit [ABSTRACT FROM AUTHOR]

Many models of self-assembly have been shown to be capable of performing computation. Tile Automata was recently introduced combining features of both Cellular Automata and the 2-Handed Model of self-assembly both capable of universal computation. In this work we study the complexity of Tile Automata utilizing features inherited from the two models mentioned above. We first present a construction for simulating Turing machines that performs both covert and fuel efficient computation. We then explore the capabilities of limited Tile Automata systems such as 1-dimensional systems (all assemblies are of height 1) and freezing systems (tiles may not repeat states). Using these results we provide a connection between the problem of finding the largest uniquely producible assembly using n states and the busy beaver problem for non-freezing systems and provide a freezing system capable of uniquely assembling an assembly whose length is exponential in the number of states of the system. We finish by exploring the complexity of the Unique Assembly Verification problem in Tile Automata with different limitations such as freezing and systems without the power of detachment. [ABSTRACT FROM AUTHOR]

Reintroduction and rewilding initiatives are key strategies to reverse human impacts on ecosystems and re‐establish natural processes. However, rewilding may involve complex management scenarios, because many expanding species can have economic impacts and cause human–wildlife conflicts. Conflicts can be particularly challenging when carnivores, large herbivores and ecosystem engineers are involved. The Eurasian beaver (Castor fiber) is a key ecosystem engineer that was once present in a large part of the Palearctic, but in Medieval times underwent a severe decline due to the joint effects of habitat loss and hunting. Subsequent legal protection and reintroductions triggered the recovery of the species through most of its original range. Eurasian beavers recently started the recolonization of Italy, because of the joint effects of natural dispersal (from Austria to northern Italy) and illegal reintroductions (central Italy). The lack of data on the most likely colonization routes hampers appropriate management of this species. Here, we identified the areas where beaver populations are most likely to arrive in the near future within Europe, with a specific focus on Italy. First, we developed spatially cross‐validated species distribution models to identify the areas with the highest suitability for the Eurasian beaver in Europe. Second, we used connectivity modelling to assess the possible expansion routes of this species in Italy. Large areas of Europe are suitable for the beaver and may soon be colonized. The connectivity model showed a high potential for expansion from central Italy to surrounding areas, while the high isolation of northern Italy populations suggests a slower expansion. Our results can help environmental managers to understand where to focus both the future monitoring of beaver populations and actions aimed at preventing and mitigating possible human–wildlife conflicts that could arise from the expansion of an environmental engineer such as the beaver. [ABSTRACT FROM AUTHOR]

This study evaluated the chemical, physical and sensory properties of canned beaver and nutria. These animals are currently hunted not for their meat, but to reduce their numbers in the wild. The situation is complicated by the fact that both species are on the relevant lists. However, while the beaver is a protected animal, the nutria is an invasive species. This leads to complications in the application of the relevant legislation. Hunters are therefore limited in what they can do with the meat of these species. The chemical composition of the products did not differ (p > 0.05). Canned beaver was the darkest (p < 0.05) product and canned nutria the softest (p < 0.05). Both meat products were sensory acceptable and no off-odour or off-flavour was perceived. Canning meat is something that hunters can easily do at home, and the resulting product meets all the requirements for food safety. [ABSTRACT FROM AUTHOR]

Metacommunity theory predicts that the relative importance of regional and local processes structuring communities will change over ecological succession. Determining effects of these processes on taxonomic and evolutionary diversity in spatially structured freshwater habitats of different successional stages may greatly improve understanding of the maintenance of diversity across temporal and spatial scales. In this study, we evaluated crayfish diversity at local and regional scales in pond metacommunities undergoing secondary succession from beaver (Castor canadensis) disturbance. Following theoretical predictions from metacommunity ecology of the increasing importance of local processes over succession, we hypothesised a decline in crayfish local and β diversity over succession from stronger local structuring as the older ponds may provide less suitable habitat than streams.Crayfish species and phylogenetic diversity were evaluated in beaver pond metacommunities and reference headwater streams located in three catchment regions. DNA sequences from the mitochondrial cytochrome oxidase I gene were used to assign crayfish to species for community and phylogenetic diversity tests. Local and β diversity were contrasted across beaver ponds ranging in age from 24 to 70 years and as a function of metacommunity processes.Counter to predictions, local species diversity among streams and the successional stages of ponds categorised by age class (24–39 years; 42–57 years; 60–70 years) did not differ, but community and phylogenetic convergence occurred in the oldest pond ecosystems. Crayfish community composition differed between the youngest and oldest ponds, resulting from higher abundance in the youngest ponds and community convergence in the oldest ponds. The association between community composition and the environment was strongest in streams and decoupled with pond age. In contrast, the correlation between intraspecific haplotype composition and the environment increased over succession. Among the three metacommunities, the regional crayfish species diversity arose from a combination of the temporal and environmental drivers from beaver‐constructed ecosystems and dispersal limitation within catchments.This study represents the first investigation of the taxonomic and phylogenetic diversity response to the successional stages of beaver pond metacommunities. The detection of differential crayfish composition and haplotype sorting to pond age suggests a role for local structuring and further indicates that future studies should acknowledge succession in shaping species diversity at local and regional scales. Dispersal limitation within catchment regions probably contributes to the evolution of crayfish species diversity in metacommunities and the overall maintenance of biodiversity.The results support a transition in community and freshwater ecology from a recent emphasis on spatial processes towards the integration of temporal drivers to better identify regulators of taxonomic and phylogenetic diversity across scales. [ABSTRACT FROM AUTHOR]

Riparian ecosystems are valuable habitats for bats, due to high densities of emergent aquatic invertebrates that provide high-quality feeding areas. Throughout Europe, decline and extirpation of European beaver (Castor fiber) has been a key driver in the decline of the extent and quality of riparian habitat, and thus recolonisation has considerable potential to restore degraded areas. Previous research has shown that beaver-modified ecosystems can support more bats, but the assumed causal link (an increase in invertebrate prey) has not been tested. Here, we study bat activity and richness/abundance of aquatic macroinvertebrates at a site where free-roaming beavers have colonised naturally from a nearby (unofficial) release location versus a nearby control site with very similar hydrology and habitat matrix. Bat activity was recorded using walked activity transects and fixed-point acoustic detectors. Although bat species richness was similar, bat activity was substantially and significantly higher at the beaver site versus the control site overall (42.7%) and for four specific taxa: soprano pipistrelle (Pipistrellus pygmaeus; 8.4%), Daubenton's (Myotis daubentonii; 46.5%), common pipistrelle (Pipistrellus pipistrellus; 110.4%) and common noctule (Nyctalus noctula; 170.9%). Richness of the larvae/nymphs of emergent aquatic macroinvertebrate species known to form an important part of bat diet was 205.5% higher at the beaver site compared to the control site, while abundance was 817.4% higher. Overall bat activity was also linked to habitat (lotic > lentic), survey method (transect > fixed-point), and season (May–July peak). This is the first evidence of a likely causal link between beaver recolonisation and bat activity via an increase in abundance of key aquatic invertebrate prey and we recommended that benefits of beaver reintroduction on bats be considered in future feasibility studies. [ABSTRACT FROM AUTHOR]

On a global scale, species biodiversity is declining rapidly, including that of terrestrial invertebrates. Environmental heterogeneity is viewed as a key factor promoting biodiversity, and previous studies have shown how beavers can have a profound effect on both habitat heterogeneity and abundance and diversity of a plethora of water-related and terrestrial organisms. However, less is known about the effects of beavers and successional stages on the terrestrial invertebrate community. Here, we review existing knowledge and outline research trajectories to improve our understanding of how beavers affect the terrestrial invertebrate community with special focus on the importance of each successional stage that beavers provide on terrestrial invertebrates. Although beavers can have a large impact on the terrestrial invertebrate community, more studies are needed that take into consideration successional stages and with standardized sampling designs. A better understanding of how beaver activity affects the terrestrial invertebrate community can help in conservation of endangered species and restoration of biodiversity in terrestrial habitats. [ABSTRACT FROM AUTHOR]

Dam building by beaver (Castor spp.) slows water movement through montane valleys, increasing transient water storage and the diversity of residence times. In some cases, water storage created by beaver dam construction is correlated to changes in streamflow magnitude and timing. However, the total amount of additional surface and groundwater storage that beaver dams may create (and, thus, their maximum potential impact on streamflow) has not been contextualized in the water balance of larger river basins. We estimate the potential transient water storage increases that could be created at 5, 25, 50, and 100% of maximum modeled beaver dam capacity in the Bear River basin, USA, by adapting the height above nearest drainage (HAND) algorithm to spatially estimate surface water storage. Surface water storage estimates were combined with the MODFLOW groundwater model to estimate potential increases in groundwater storage throughout the basin. We tested four scenarios to estimate potential transient water storage increases resulting from the construction of 1179 to 34,897 beaver dams, and estimated surface water storage to range from 57.5 to 72.8 m3 per dam and groundwater storage to range from 182.2 to 313.3 m3 per dam. Overall, we estimate that beaver dam construction could increase transient water storage by up to 10.38 million m3 in the Bear River basin. We further contextualize beaver dam-related water storage increases with streamflow, reservoir, and snowpack volumes. [ABSTRACT FROM AUTHOR]

Natural rivers are inherently dynamic. Spatial and temporal variations in water, sediment, and wood fluxes both cause and respond to an increase in geomorphic heterogeneity within the river corridor. We analyze 16 two‐km river corridor segments of the Swan River in Montana, USA to examine relationships between logjams (distribution density, count, and persistence), channel dynamism (total sinuosity and average channel migration), and geomorphic heterogeneity (patch density) in the river corridor. We hypothesize that (a) more dynamic river segments correlate with a greater presence, persistence, and distribution of logjams; (b) higher annual peak discharges correspond with greater channel dynamism and logjam presence and distribution; and (c) greater logjam distribution densities and channel dynamism are predictive of more spatially heterogeneous sections of the river corridor. Our results suggest that, first, decadal‐scale channel dynamism, as reflected in total sinuosity, corresponds to greater numbers of logjams and greater persistence of logjams through time. Second, higher peak discharges correspond to greater presence and distribution of logjams, but not to greater channel dynamism. Third, greater geomorphic heterogeneity in the river corridor, as reflected in the spatial distribution of landscape patch density, is explained by greater logjam distribution density, total sinuosity, and proportions of beaver meadows. Our results reflect the complex interactions of water, sediment, and wood in river corridors; the difficulties of interpreting causal relationships among these variables through time; and the importance of spatial and temporal analyses of past and present river processes to understand future river conditions. Plain Language Summary: Natural rivers inherently experience changes in their shape, channel locations, and floodplain compositions across space and time due to variations in water, sediment, and wood fluxes. We analyze 16 two‐km segments of the Swan River in Montana, USA to examine relationships between logjams (the total count, persistence over a decade, and distribution density), how much the main and secondary channels move with time, and how patchy the river corridor is. We hypothesize that (a) where there is more channel movement, there will be more logjams; (b) years with higher flow correspond with more logjams and channel movement; and (c) logjams and channel movement play a role in explaining the patchiness of the river corridor. Our results suggest that there is a positive relationship between channel movement and logjams. Second, higher flows correspond to greater values of logjams, but not to channel movement. Third, persistent values of river corridor patchiness are explained logjam density, beaver meadows, and channel movement. Our results reflect the complex interactions of water, sediment, and wood in rivers and the importance of spatial and temporal analyses of past and present river processes to understand future river conditions. Key Points: Decadal‐scale channel dynamism, as reflected in total sinuosity, corresponds to greater logjam presence and persistence through timeHigher peak discharges correspond with a greater number and distribution of logjams, but not with greater channel dynamismLogjams, channel dynamism, and beaver meadows increase spatial heterogeneity, as reflected in landscape patch density [ABSTRACT FROM AUTHOR]

Abstracts are not associated with Essays. –the SFEWS Editors

After ~100 years of absence, beaver (Castor canadensis) were reintroduced to the San Pedro River in southeastern Arizona in 1999. Total streamflow in the San Pedro River has decreased during the past 90 years. We hypothesize that beaver under drought conditions may be limited in mobility due to low water and predation risk. Between 12 May and 16 June 2022, we used Reconyx Hyperfire 2 trail cameras to capture the behavior of beaver near a large dam on the San Pedro River. The site where the beaver built their dam has intermittent water flow and typically dries out every year during periods of low precipitation and high temperature. Beaver activity increased shortly before and after the pond dried out on 29 May 2022 (from 26 May to 31 May). We documented 7 separate occasions when beaver dragged large willow branches (~1 to 3 m long) with leaves away from the dam toward a presumed bank lodge. Beaver were only observed twice (both instances on 5 June) during the following 15 days of the study. This evidence suggests that beaver could stay in bank lodges during periods of low water flow, eating from their food caches. This unique caching behavior may be seen in beaver populations in desert climates or other drought-stressed environments. Mountain lions (Puma concolor) were observed at our study site before and after the pond dried, suggesting that this food-caching behavior has real value to the survival of beaver in the San Pedro River. [ABSTRACT FROM AUTHOR]

Stream restoration programs employ beaver‐related restoration techniques, including beaver translocations and installation of beaver dam analogs (BDA), to create complex in‐stream habitat. We investigated whether BDA installations improved the probability of translocated beavers surviving and colonizing a section of a degraded desert river. We translocated beavers fitted with tracking devices to the Price River, Utah, United States, for 2 years before and after BDAs were installed. We monitored survival and site fidelity of beavers to estimate apparent survival (φ), using model selection to evaluate models with BDA, flow, and other factors hypothesized to relate to apparent survival. We found similar apparent survival 8 weeks post‐release of pre‐BDA (φ = 0.50 ± 0.08 SE) and post‐BDA beavers (φ = 0.41 ± 0.06 SE). There were 15 predator‐caused mortalities and 39 beavers emigrated out of the study site. Top models indicated apparent survival was negatively related to mean flow. Of the 70 BDAs constructed, beaver activity was detected on only two structures and the number of intact natural dams decreased due to monsoon floods. Our results suggest BDAs may not improve survival and site fidelity of translocated beavers in desert river systems. Instead, the dynamic flow of desert rivers and negative relationship between flow and apparent survival suggest the timing of release may be an important consideration for successful beaver translocation. Additional research is needed to understand how habitat, food availability, individual behavior, and resident conspecifics influence beaver translocation success. [ABSTRACT FROM AUTHOR]

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As known "ecosystem engineers", beavers influence river hydrology, geomorphology, biochemistry, and biological assemblages. However, there is a lack of research regarding the effects of beaver activities on freshwater meiofauna. In this study, we investigated the taxonomic and functional composition of the benthic copepod assemblage of a segment of the Tiber River (Italy) where a beaver dam, created about 7 weeks before our survey, had formed a semi-lentic habitat upstream and a lotic habitat downstream of the dam. We also analyzed the copepod assemblage before and after a flood event that destroyed the beaver dam, providing a unique opportunity to observe changes in a naturally reversing scenario. Our analyses revealed that, while the taxonomic composition and functional traits of the copepod assemblage remained largely unchanged across the recently formed semi-lentic and lotic habitats, substantial differences were evident between the dammed and undammed states. The dammed state showed lower copepod abundances, biomass, and functionality than the undammed one. These results highlight the role of beaver dams in changing the composition and functionality of meiofaunal assemblages offering insights into the dynamic interactions within aquatic ecosystems. [ABSTRACT FROM AUTHOR]

A new species of ambrosia beetle Indocryphalus chiyui Lin & Beaver (tribe Xyloterini LeConte, 1876) from Taiwan is described. The species is monogamous and xylomycetophagous, breeding in Castanopsis cuspidata var. carlesii (Hemsl.) Yamazaki (Fagaceae). Indocryphalus sordidus (Blandford) is recorded for the first time from Taiwan. Diagnostic characters, biological data and a key to species of Indocryphalus in Taiwan are provided. [ABSTRACT FROM AUTHOR]

The Microperus ambrosia beetle fauna of Taiwan is reviewed. Microperus alpha (Beeson, 1929), M. kadoyamaensis (Murayama, 1934), M. kirishimanus (Murayama, 1955), M. perparvus (Sampson, 1922), M. quercicola (Eggers, 1926) have all been previously recorded from Taiwan. Microperus bucolicus Sittichaya, Smith & Beaver, 2021 and M. latesalebrinus Smith, Beaver & Cognato, 2020 are new country records for Taiwan. Of which, the males of M. alpha, M. bucolicus, M. kadoyamaensis, M. latesalebrinus, M. perparvus, and M. quercicola are described for the first time. In this study, we document a likely occurrence of mycocleptism by M. bucolicus. Diagnostic characters, biological data and a key to species in Taiwan are provided. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are some of the most biodiverse habitats, but they are among the most endangered due to human activities. In this context, beavers represent a nature‐based solutions to preserve and repair freshwater ecosystem, given their important role as ecosystem engineers. However, in an environment modified by humans, beaver activities frequently create conflicts masking the positive effects of this rodent. Therefore, the management of beaver populations and human–beaver conflicts is needed.This article investigates the literature about beaver management through a bibliometric analysis to understand past, current, and future response. Moreover, it quantifies the number of studies that consider beavers as a resource, and it identifies the emerging themes in the field.The bibliometric analysis was performed considering a total of 415 documents with the software VOSviewer and the R web interface for bibliometrix Biblioshiny.The analysis presented here provides a complete view of past, present, and future management approaches and responses at the base of beaver management strategies. Three main results emerged. Firstly, a rising tendency in the number of publications about beavers that are directly linked to the populations development and spread has detected. Secondly, only 4.3% of scientific literature has referred to beaver‐related restoration. Thirdly, the 'human perceptions' has resulted in the emerging field investigated.Findings suggest that there is a lot of research interest about beaver management. The beaver is still poorly managed as a tool for freshwater ecosystem restoration. The management is shifting from studies focused more so on beaver ecology to others mainly focused on the beaver effects and the human dimension.This review provides a starting point for future research on beavers and suggests the development of socio‐ecological management models that consider benefits and impacts of beavers. This will help the decision‐making process of conservation and restoration initiatives. [ABSTRACT FROM AUTHOR]

In this paper, by using GNSS technologies, some features of the distribution and some morphometric parameters of dams and ponds created by the Eurasian beaver (Castor fiber L.) along ten rivers of the Volga-Kama region of European Russia were identified. Detected features depend on the geomorphological, lithological, and landscape features of these rivers and their basins. The significant role of river slopes, as well as landscape zoning, in the distribution of beaver dams and ponds along small rivers in the study region is shown. In the rivers under study, almost all beaver constructions are located on riverbed slopes of less than 3% (most often, less than 2%). In the south of the forest zone (the southern taiga of the Vyatka River basin), the majority of dams and ponds (about 90%) are located on slopes of less than 1%, while, within the uplands of the forest-steppe zone, this location varies depending on the length of the rivers. In general, the greater the average slope of the river (the greater the average elevation of the river basin), the lower, other things being equal, the degree of beaver transformation of such rivers. This feature is better expressed in the rivers of the forest landscape zone and less expressed in the rivers flowing in the forest-steppe zone. Analysis of the morphometric parameters of beaver dams shows statistically significant trends towards an increase in their average height, as the channel slopes increase. Statistically significant trends were also identified towards a decrease in the length of dams and the length of associated ponds, with an increase in channel slopes. It is noteworthy that the critical values of the slope for a statistically significant and relatively sharp change in these parameters are 1.45%, 1.07 (or 0.54)%, and 0.65 (or 0.47)%, respectively. The greatest average heights of beaver dams are confined to those rivers where their basins are composed of loamy rocks/soils (especially those that are poorly plowed), compared with "sandy" river basins. This may be due to the peculiarities of the ratio of surface and underground water runoff in these basins and, as a consequence, different intensities of snowmelt- and rainfall-induced flood flow. We assume that the above-mentioned features reflect the early stages of beaver expansion (population growth) in the studied rivers. [ABSTRACT FROM AUTHOR]