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Conserving landscapes used by multiple stakeholder groups requires understanding of what each stakeholder values. Here we employed a semi-structured, participatory approach to identify features of value in the terrestrial Antarctic Peninsula related to biodiversity, science and tourism. Stakeholders identified 115 features, ranging from Adélie penguin colonies to sites suitable for snowshoeing tourists. We split the features into seven broad categories: science, tourism, historic, biodiversity, geographic, habitat, and intrinsic features, finding that the biodiversity category contained the most features of any one category, while science stakeholders identified the most features of any stakeholder group. Stakeholders have overlapping interests in some features, particularly for seals and seabirds, indicating that thoughtful consideration of their inclusion in future management is required. Acknowledging the importance of tourism and other social features in Antarctica and ensuring their integration into conservation planning and assessment will increase the likelihood of implementing successful environmental management strategies into the future. [ABSTRACT FROM AUTHOR]

The loggerhead turtle Caretta caretta is a large marine turtle with a cosmopolitan repartition in warm and temperate waters of the planet. The South Pacific subpopulation is classified as 'Critically Endangered' on the IUCN Red List, based on the estimated demographic decline. This precarious situation engages an urgent need to monitor nesting populations in order to highlight conservation priorities and to ensure their efficiency over time. New Caledonia encompasses a large number of micro and distant nesting sites, localized on coral islets widely distributed across its large lagoon. Adequately surveying nesting activities on those hard-to-reach beaches can prove to be challenging. As a result, important knowledge gaps prevail in those high-potential nesting habitats. For the first time, an innovative monitoring scheme was conducted to assess the intensity of nesting activities, considered as a proxy of the population size, on an exhaustive set of islets located in the 'Grand Lagon Sud' area. These data were analyzed using a set of statistical methods specially designed to produce phenology and nesting activity estimates using Bayesian methods. This analysis revealed that this rookery hosts a large nesting colony, with a mean annual estimate of 437 nests (95% Credible Interval = 328–582). These numbers exceed that of the previous estimated annual number of loggerhead turtle nests in New Caledonia, highlighting the exceptional nature of this area. Considering the fact that similar high-potential aggregations have been identified in other parts of New Caledonia, but failed to be comprehensively assessed to this day, we recommend carrying out this replicable monitoring scheme to other locations. It could allow a significant re-evaluation of the New Caledonian nesting population importance and, ultimately, of its prevailing responsibility for the protection of this patrimonial yet endangered species. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex (MHC) plays a key role in the adaptive immune system of vertebrates, and is known to influence mate choice in many species. In birds, the MHC has been extensively examined but mainly in galliforms and passerines while other taxa that represent specific ecological and evolutionary life-histories, like seabirds, are underexamined. Here, we characterized diversity of MHC Class II B exon 2 in a colonial pelagic seabird, the Little Auk (or Dovekie Alle alle). We further examined whether MHC variation could be maintained through balancing selection and disassortative mating. We found high polymorphism at the genotyped MHC fragment, characterizing 99 distinct alleles across 140 individuals from three populations. The alleles frequencies exhibited a similar skewed distribution in both sexes, with the four most commonly occurring alleles representing approximately 35% of allelic variation. The results of a Bayesian site-by-site selection analysis suggest evidence of balancing selection and no direct evidence for MHC-dependent disassortative mating preferences in the Little Auk. The latter result might be attributed to the high overall polymorphism of the examined fragment, which itself may be maintained by the large population size of the species. [ABSTRACT FROM AUTHOR]

Several studies have examined the potential impacts of climate change on the abundance and distribution of Antarctic penguin species, particularly in the genus Pygoscelis. However, less attention has been given to traditionally sub-Antarctic penguin species. The Macaroni Penguin (Eudyptes chrysolophus) is one such sub-Antarctic species whose presence in Antarctica has historically been restricted to colonies on the South Shetland Islands and adjacent islands, but their status in the region has not been updated in decades. We compiled census data on all known Macaroni Penguin breeding colonies in the Antarctic Peninsula region in order to estimate the total Antarctic population. We estimate a population of 8053 breeding pairs for the region, which represents an approximately 10.7% increase since the last regional census in 1993. We identify local population changes at different colonies in comparison to historical census data. We also identify vagrant sightings in the region, as they may reflect prospecting of new breeding habitat, especially as ice-free areas continue to expand due to climate change. Our assessment identifies the South Shetland Islands and South Orkney Islands as notable data gaps. [ABSTRACT FROM AUTHOR]

This article discusses the presence of anthropogenic material in Crested Caracara nests in Argentina and its impact on electrical transmission lines. The study found that the material in the nests caused voltage drops and intermittent power outages by bridging the air gap between the transmission pylons and the energized conductors. The anthropogenic material identified in the nests included baling twine and electric fence rope. The article emphasizes the need to properly discard anthropogenic materials to prevent negative consequences for power companies, the population, and biodiversity. The given text is a list of references cited in a research article about the materials found in Crested Caracara nests in Argentina. The references include studies on nest building behavior, the use of anthropogenic nest substrates, and the impact of bird-related power outages. The article highlights the presence of human-made materials in the nests and the potential consequences of these materials for the birds and the power infrastructure. The references provide a range of perspectives on the topic, including economic costs, mitigation strategies, and the use of unmanned aircraft systems for assessment. [Extracted from the article]

Microplastic pollution threatens some of the world's most iconic locations for marine biodiversity, including the remote Galápagos Islands, Ecuador. Using the Galápagos penguin (Spheniscus mendiculus) as a sentinel species, the present study assessed microplastics and suspected anthropogenic cellulose concentrations in surface seawater and zooplankton near Santa Cruz and Galápagos penguin colonies (Floreana, Isabela, Santiago), as well as in penguin potential prey (anchovies, mullets, milkfish) and penguin scat. On average, 0.40 ± 0.32 microplastics L−1 were found in surface seawater (<10 μm; n = 63 L), while 0.003, 0.27, and 5.12 microplastics individual−1 were found in zooplankton (n = 3372), anchovies (n = 11), and mullets (n = 6), respectively. The highest concentration (27 microplastics individual−1) was observed in a single milkfish. Calculations based on microplastics per gram of prey, in a potential diet composition scenario, suggest that the Galápagos penguin may consume 2881 to 9602 microplastics daily from prey. Despite this, no microplastics or cellulose were identified in 3.40 g of guano collected from two penguins. Our study confirms microplastic exposure in the pelagic food web and endangered penguin species within the UNESCO World Heritage site Galápagos Islands, which can be used to inform regional and international policies to mitigate plastic pollution and conserve biodiversity in the global ocean. Environ Toxicol Chem 2024;43:1442–1457. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

According to the 'selfish herd' hypothesis, most seabird species breed colonially so that individuals can decrease their risk of predation by forming compact groups. However, costs and benefits associated with colonial breeding may not be evenly distributed among individuals within a colony. At Adélie penguin colonies, individuals nesting on the periphery of subcolonies (distinct groups of nests) may experience higher rates of nest predation by south polar skuas, and thus the optimal aggregation pattern for Adélie penguins may be within groups that minimize the proportion of edge nests. Nevertheless, some penguins choose to nest solitarily, at significant distances from conspecifics. We tracked 50 of these "solitary-nesting" Adélie penguins at Cape Crozier, a large colony on Ross Island, during the 2021 nesting season and compared their breeding success to individuals nesting within subcolony boundaries. We found that both solitary and subcolony nests successfully raised chicks large enough to join crèches and left unattended by adults. However, chicks from solitary nests exhibited a rate of mortality more than six times higher during the transition from nest brooding/guarding to crèche stage. In the 2022 nesting season, we found that solitary nests which had previously hosted actively breeding penguins were more likely to be re-occupied. Solitary nesting therefore appears to be a less-successful alternative to breeding within subcolonies, but enough individuals could be successful with this approach to maintain the apparently disadvantageous behavior and effectively pioneer previously unused locations, possibly including eventual new colony locations. [ABSTRACT FROM AUTHOR]

Animals that feed socially can sometimes better locate prey, often by transferring information about food that is patchy, dense, and temporally and spatially unpredictable. Information transfer is a potential benefit of living in breeding colonies where unsuccessful foragers can more readily locate successful ones and thereby improve feeding efficiency. Most studies on social foraging have been short term, and how long‐term environmental change affects both foraging strategies and the associated benefits of coloniality is generally unknown. In the colonial Cliff Swallow (Petrochelidon pyrrhonota), we examined how social foraging, information transfer, and feeding ecology changed over a 40‐year period in western Nebraska. Relative to the 1980s, Cliff Swallows in 2016–2022 were more likely to forage solitarily or in smaller groups, spent less time foraging, were more successful as solitaries, fed in more variable locations, and engaged less in information transfer at the colony site. The total mass of insects brought back to nestlings per parental visit declined over the study. The diversity of insect families captured increased over time, and some insect taxa dropped out of the diet, although the three most common insect families remained the same over the decades. Nestling Cliff Swallow body mass at 10 days of age and the number of nestlings surviving per nest declined more sharply with colony size in 2015–2022 than in 1984–1991 at sites where the confounding effects of ectoparasites were removed. Adult body mass during the provisioning of nestlings was lower in more recent years, but the change did not vary with colony size. The reason(s) for the reduction in social foraging and information transfer over time is unclear, but the consequence is that colonial nesting may no longer offer the same fitness advantages for Cliff Swallows as in the 1980s. The results illustrate the flexibility of foraging behavior and dynamic shifts in the potential selective pressures for group living. [ABSTRACT FROM AUTHOR]

In recent years the bull ant Myrmecia midas Clark, 1951, has attracted attention for its impressive visual navigation during its nocturnal activity. Still, a basic understanding of this species' ecology is lacking. Nest relocation and colony fissions are rarely observed and largely undocumented in M. midas colonies. In the current study, we quantified the nest-relocation and colony-splitting behaviour of suburban populations of M. midas in response to flooding in its habitat, caused by record rainfalls in eastern Australia in 2022. The flooding caused the destruction of nest chambers and disrupted colony activities. We documented nine relocations of the fifty observed colonies with another four split into 12 different colonies. Most relocations occurred a few days after one period of especially heavy rains. We collected several characteristics of these relocations: the distance of a nest from the nearest tree, the elevation of the nest above ground level and the diameter of the nest entrance, with all of these metrics predicting whether a colony moved after heavy rains. Moreover, we conducted excavations of some abandoned colonies, uncovering evidence of an internal collapse of nest chambers due to heavy flooding, which likely induced the nest relocation and colony fission in M. midas. In normal weather, we have not observed any colony relocating, suggesting that moving may bear a fitness cost. [ABSTRACT FROM AUTHOR]

How to manage harvest under great uncertainty is a fundamental question for many wildlife managers, particularly when resources necessary to estimate abundance or population trends are limited. The large Newfoundland and Labrador murre hunt is the only licensed harvest of seabirds in Canada. Though harvest of thick‐billed murres (Uria lomvia) and common murres (Uria aalge) has declined considerably since the 1960−1970s from >500,000 birds taken annually to approximately 100,000 annually in recent years, potential murre colony declines across the North Atlantic have again triggered concerns over the sustainability of murre harvest in Canada. The effect of current harvest is difficult to assess because there is considerable uncertainty in recent population size, trend, demographic rates, licensed harvest, fisheries bycatch, and illegal harvest. To assess the situation, we simulated the population size necessary to sustain current levels of approximated anthropogenic mortality using a potential biological removal approach, which simplifies and constrains population processes to a few key variables. Based on these simulations, the Canadian licensed harvest of thick‐billed murre is consistent with conservation management objectives, as is common murre licensed harvest and fisheries bycatch. Adding estimated illegal harvest resulted in unstainable mortality levels in both species. While wildlife managers will need to formally assess the relative costs and benefits of reducing uncertainty in this system through improved harvest and population monitoring, illegal harvest and commercialization need to be addressed to manage Canadian murre populations. Potential biological removal approaches can be a useful framework to assess harvest management decisions for marine birds and other data‐limited species. [ABSTRACT FROM AUTHOR]

The genetic identification of evolutionary significant units and information on their connectivity can be used to design effective management and conservation plans for species of concern. Despite having high dispersal capacity, several seabird species show population structure due to both abiotic and biotic barriers to gene flow. The Kelp Gull is the most abundant species of gull in the southern hemisphere. In Argentina it reproduces in both marine and freshwater environments, with more than 100,000 breeding pairs following a metapopulation dynamic across 140 colonies in the Atlantic coast of Patagonia. However, little is known about the demography and connectivity of inland populations. We aim to provide information on the connectivity of the largest freshwater colonies (those from Nahuel Huapi Lake) with the closest Pacific and Atlantic populations to evaluate if these freshwater colonies are receiving immigrants from the larger coastal populations. We sampled three geographic regions (Nahuel Huapi Lake and the Atlantic and Pacific coasts) and employed a reduced-representation genomic approach to genotype individuals for single-nucleotide polymorphisms (SNPs). Using clustering and phylogenetic analyses we found three genetic groups, each corresponding to one of our sampled regions. Individuals from marine environments are more closely related to each other than to those from Nahuel Huapi Lake, indicating that the latter population constitutes the first freshwater Kelp Gull colony to be identified as an evolutionary significant unit in Patagonia. [ABSTRACT FROM AUTHOR]

Southern giant petrels (Macronectes giganteus) are important consumers that range across the oceans throughout the southern hemisphere. In Argentina, previous studies have shown they eat primarily pinnipeds and penguins, which they are assumed to scavenge, although there are occasional anecdotes of them attacking living penguins. Here we describe a predation attempt by a trio of southern giant petrels on a molting adult Magellanic penguin (Spheniscus magellanicus) at the large colony at Punta Tombo, Argentina. We relate giant petrel attendance patterns at the colony to the penguins' phenology, showing how giant petrel numbers rise with the increasing prevalence of vulnerable penguins. We suggest that living penguins—both fledglings and adults—may constitute a more seasonally significant proportion of the giant petrel diet than previously assumed, and their capture may represent a specialized predation technique. [ABSTRACT FROM AUTHOR]

Since the Antarctic continent is not exempt from human disturbances, it is necessary to generate information on the residues of anthropogenic origin in these environments. The main aim of our study was to determine the presence and abundance of anthropogenic residues found around the pygoscelid penguin colony of the Antarctic Specially Protected Area No. 132 "Potter Peninsula" (25 de Mayo/King George Island, South Shetland Islands, Antarctica), in order to contribute with information on the distribution of anthropogenic residues that have been recorded in different regions of the Antarctic Peninsula and the Scotia Arc. A total of 37 anthropogenic elements (821.73 g) were collected between September 2021 and March 2022. According to the type of material, the most abundant were 'various plastic residue' (54.05%) and 'consumer plastic residue' (35.14%). Regarding size, most of the elements had a length between 15 and 30 cm, followed by those with a length < 5 cm, while regarding color, white residues were the most common (n = 9), followed by transparent ones (n = 7). The origin of these residues could be found in fishing, tourism, logistics and scientific activities. It is important to continue monitoring residues to assess potential impacts on biota and the environment. [ABSTRACT FROM AUTHOR]

Stoneworts (Charales) are green algae that represent an important food resource for many waterbird species in Europe and elsewhere. Browsing avian herbivores (e.g. swan, goose, duck and coot species) consume Charales plant vegetative parts, by head‐dipping, up‐ending or diving. A lower fibre content and longer growing season may make Charales as attractive to such herbivores as sympatric submerged higher plant species in some circumstances. Charales respond to environmental stress (e.g. drought) by producing abundant diaspores, in the form of oospores (sexual) and bulbils (asexual), both rich in starch, generating abundant food for waterbirds at critical stages in their annual migratory cycles. Waterbirds feed on these by diving (e.g. common pochard Aythya ferina and red‐crested pochard Netta rufina) or by filtering from the water column (e.g. dabbling duck species), ensuring dispersal of sexually produced and vegetative diaspores locally (because of predator swamping) and remotely (through endo‐ and ectozoochorous dispersal by long‐distance migratory waterbirds). Greater invertebrate density and diversity associated with Charales canopies enhances their attractiveness over other submerged macrophyte beds to diving predators [e.g. tufted duck Aythya fuligula, common pochard and Eurasian coot Fulica atra (hereafter coot)]. Fish fry preying on these invertebrates use such vegetation as predator cover, in turn providing prey for avian piscivores such as grebes and cormorants. Abundant Charales contribute to maintaining a transparent water column due to canopy density, nutrient effects, dampening of sedimentation/remobilisation of suspended matter and nutrients and allelopathic effects on other plants (especially phytoplankton). Shallow, relatively eutrophic waters can flip between clear‐water high‐biodiversity (where Charales thrive) and turbid species‐poor depauperate stable states (lacking Charales). Shifts between turbid conditions and rich submerged Charales beds have profound elevating effects on aquatic diversity, to which waterbirds show rapid aggregative responses, making them ideal indicator species of ecological change; in the case of Charales specialists (such as red‐crested and common pochard), indicators of the presence and abundance of these plants. Large‐bodied colonial nesting birds (e.g. cormorants, gulls, heron and egrets) aggregating along lake shores contribute high N and P loadings to water bodies sensitive to such external and internal inputs and can cause local eutrophication and potential loss of Charales. Despite variation from complete seasonal removal of Charales biomass to undetectable grazing effects by herbivorous birds, evidence suggests little effect of avian grazing on biomass accumulation or the stability of community composition (under otherwise stable conditions), but we urge more research on this under‐researched topic. We also lack investigations of the relative foraging profitability of different Charales organs to waterbirds and the degree of viability of gyrogonites (fertilised and calcified oospores), vegetative bulbils and plant fragments after passage through the guts of waterbirds. We especially need to understand better how much the carbonate armour of these organs affects their viability/dispersal via waterbirds and urge more research on these neglected plants and their relationships and interactions with other organisms in the aquatic biota. [ABSTRACT FROM AUTHOR]

Seabirds create fluxes of nutrients from marine to terrestrial ecosystems that influence the food webs of small islands. We investigated how guano inputs shape terrestrial food webs by comparing species of selected plant and animal species in a red-footed booby colony in Mona Island (Puerto Rico, Caribbean Sea), to sites of the island lacking guano inputs. We quantified guano deposition and its relationship to plant biomass production, fecundity and density, as well as the activity of native and introduced animal species. In general, guano inputs increased the gross primary plant productivity, size, and fecundity by twofold. Guano inputs were also associated with twofold increases in density of Anole lizards, but also to increases in the activity of introduced pigs (> 500%), goats (> 30%), and cats (> 500%), which negatively impact native species. In particular, elevated pig and cat activity within the booby colony was correlated with lower activity of endemic ground lizards and of introduced rats. Our results also suggest that severe droughts associated with climate change exacerbate the negative effects that introduced species have on vegetation and reduce the positive effects of seabird guano inputs. Our findings underscore the importance of allochthonous guano inputs in subsidizing plant productivity and native and endemic species in small oceanic islands, but also in increasing the negative impacts of introduced mammals. Management and conservation efforts should focus on the exclusion (or eradication) of introduced mammals, particularly pigs and goats, from remnant seabird colonies in Mona Island. [ABSTRACT FROM AUTHOR]

Southern giant petrels (Macronectes giganteus) are important consumers that range across the oceans throughout the southern hemisphere. In Argentina, previous studies have shown they eat primarily pinnipeds and penguins, which they are assumed to scavenge, although there are occasional anecdotes of them attacking living penguins. Here we describe a predation attempt by a trio of southern giant petrels on a molting adult Magellanic penguin (Spheniscus magellanicus) at the large colony at Punta Tombo, Argentina. We relate giant petrel attendance patterns at the colony to the penguins' phenology, showing how giant petrel numbers rise with the increasing prevalence of vulnerable penguins. We suggest that living penguins—both fledglings and adults—may constitute a more seasonally significant proportion of the giant petrel diet than previously assumed, and their capture may represent a specialized predation technique. [ABSTRACT FROM AUTHOR]

Invasive mammalian predators have devastating effects on seabird nesting colonies. A census was conducted on breeding Wedge-tailed Shearwaters Ardenna pacifica in 2016 and 2021 on D'Arros Island, Seychelles, which has been rat-free since 2003. Results were compared with an earlier population estimate to assess population growth following the rat eradication. Compared to counts in 2009, we estimated a 10-fold increase in breeding population size, with 2768 (95% confidence interval (CI) 2424-3112) and 2406 (95% CI 2143-2667) breeding pairs in 2016 and 2021, respectively. While the estimated increase is partly attributable to differences in the timing of the conducted census between the two studies, we also observed an increase in the areal extent of the population, from 3.00 to 3.85 ha (0.0300-0.0385 km2), and an increase in nesting density. Cumulatively, this indicates a true population increase. [ABSTRACT FROM AUTHOR]

The 2014-2016 Pacific marine heatwave caused unprecedented die-offs and multi-year reproductive failures for Common Murres Uria aalge along the west coast of North America. Lingering impacts, such as declines in colony attendance and productivity, have persisted at some colonies following the heatwave and are attributed largely to changes in prey availability and quality. Here, we present evidence of an additional, top-down mechanism contributing to Common Murre breeding failures on Gull Island (Alaska): disturbance of nesting birds by aerial predators and associated egg depredation. We collected time-lapse images over five murre breeding seasons (2016-2020) on Gull Island to document the frequency, duration, and intensity of disturbances caused by aerial predators, as well as to quantify disturbance-associated egg depredation. To identify seasonal and inter-annual variability of disturbances, we calculated a daily disturbance index and compared years using generalized additive models. In all years, Bald Eagles Haliaeetus leucocephalus were the primary cause of disturbance, which led to periods of prolonged colony abandonment by murres and facilitated high levels of murre egg depredation by Glaucous-winged Gulls Larus glaucescens and Herring Gulls L. argentatus. We found that the seasonality of disturbance was an important factor in determining egg depredation rates. In years when disturbance levels were high and persisted later in the season, the colony experienced complete breeding failures due to disturbance-associated egg depredation. Our study revealed that the response of nesting murres to a strong environmental perturbation, such as the Pacific marine heatwave, can be complex and involve multiple stressors from both bottom-up and top-down factors. [ABSTRACT FROM AUTHOR]

In 2022, highly pathogenic avian influenza (HPAI) virus resulted in mass mortality throughout seabird colonies in the North Atlantic Ocean. While mortalities and transmission of the virus are being documented, other effects are less understood. We documented nest abandonment and unprecedented reproductive failure by Northern Gannets Morus bassanus at Cape St. Mary's, Newfoundland and Labrador, Canada, the species' southernmost colony. Reproductive success in 2022 was the lowest on record at 17%, which was likely a result of adults abandoning the nest and succumbing to avian influenza virus (AIV) infection. Following the AIV outbreak at Cape St. Mary's, we also documented extremely long foraging trips, including the second known instance of inter-colony movement by an adult Northern Gannet, who embarked on two trips to the gannet colony on Baccalieu Island. This inter-colony movement represents a possible means of viral transmission between colonies. The effects of HPAI may have been exacerbated as a result of heat stress during a marine heatwave, which coincided with the major outbreak at this colony. As this HPAI virus could continue to circulate in seabirds, ongoing monitoring of mortality and other indirect effects of AIV outbreaks are needed to inform future impacts. [ABSTRACT FROM AUTHOR]

We explore the possibility of identifying Black-headed Gull Chroicocephalus ridibundus colonies in the saltmarshes of the Lagoon of Venice, Italy, using Google Earth satellite images. One reproductive season was considered (June 2017), based on the images available on Google Earth. This species builds nests clustered around tidal pools and tidal creeks, providing a dark background to reveal the white gulls. Images of the southern part of the lagoon (excluding fish farms) were analyzed by dividing it into sectors (n = 403) using the Google Earth grid at an elevation of 100 m above ground level. The results of the satellite count were compared with field data collected in the same season. Image analysis revealed five colonies, with excellent sensitivity (100%) but only good specificity (88%), due to the presence of numerous clear areolae falling within the spectral range of nests; these consisted of plastic litter and dry, stranded vegetation. Overall, our results indicate that Black-headed Gull colonies can be found in marsh-island habitat using Google Earth. While this approach presents sub-optimal specificity due to both the abundance of whitish debris and low image resolution, future developments in software capabilities hold the potential to overcome these limitations and enhance the accuracy of the proposed approach. [ABSTRACT FROM AUTHOR]

Great Black-backed Gulls Larus marinus and American Herring Gulls L. argentatus smithsonianus are considered dietary generalists at the population level: they consume a variety of prey types, including the adults and offspring of other seabirds, and they shift among prey types as availability varies. Atlantic Puffin Fratercula arctica adults, eggs, and chicks are often the target of depredation, and adults are also susceptible to kleptoparasitic attacks by large gulls during their summer breeding season in coastal Newfoundland, Canada. We investigated the depredation and kleptoparasitism of puffins by large gulls during July-August 2021/22 at a multi-species breeding colony on the northeast coast of Newfoundland. We hypothesized that both the inshore arrival of spawning Capelin Mallotus villosus, a key forage fish species in the region, and the onset of the puffin chick-rearing period, which typically coincide, influence puffin depredation and kleptoparasitism by large gulls. Shoreline transects on James Island revealed a decrease in new adult puffin carcasses during puffin chickrearing and Capelin spawning, with most adult puffin depredation occurring before the inshore arrival of spawning Capelin in both years. Behavioural observations (i.e., focal animal, behavioural sampling, and instantaneous scan sampling) revealed that Great Black-backed Gulls were more often present within puffin burrow areas and spent a higher proportion of time in these areas relative to American Herring Gulls, especially during Capelin spawning and puffin chick-rearing. Within puffin burrow areas, Great Black-backed Gulls depredated chicks and kleptoparasitized adults. As only ~30% of followed individuals of both gull species entered puffin burrow areas, it is possible that only a few Great Black-backed Gulls were responsible for puffin depredation and kleptoparasitism. [ABSTRACT FROM AUTHOR]

Scarce information is available on the trophic ecology and feeding habitats of the Peruvian Tern Sternula lorata. We searched 15 Peruvian Tern colonies along the coast of northern Chile during the breeding seasons of 2008 to 2018 to evaluate the tern's main food source. We collected samples of prey remains found near nests as well as prey items regurgitated by chicks and adults during our visits. We found that the Peruvian Tern is mainly piscivorous, secondarily feeding on some cephalopods and euphausiids. Pacific Saury Scomberesox saurus and Paloma Pompano Trachinotus paitensis were the main prey found near nests, but regurgitated prey was dominated by the Peruvian Anchoveta Engraulis ringens. Fish prey sizes ranged from 36 to 192 mm. These findings expand existing knowledge of the feeding ecology of this endangered seabird during its breeding season. [ABSTRACT FROM AUTHOR]

In 1942 over 150 schoolchildren from the northern Soviet cities of Arkhangel'sk and Murmansk took part in dangerous expeditions to the Arctic Archipelago of Novaia Zemlia. Their aim was to collect eggs from island bird colonies and hunt seabirds in order to supply famished cities with eggs and salted birds' carcasses. The voyages were part of the local struggle for food and a reaction to the Soviet government's urgent call to use all available local resources to ward off large‐scale famine on the Soviet home front. This essay discusses the organization, the course, and the outcome of the expeditions, and evaluates the role of specialist knowledge, local economic tradition, and various agencies—from Soviet, party, and Komsomol organizations to Soviet economic trusts and individual actors—in bringing these expeditions to life. It argues that, rather than being a centralized campaign staged by the state, the struggle for food was largely fought on the local level, with regional institutions assuming substantial responsibility and demonstrating a significant ability to improvise in their search for food. Ultimately, the population's efforts to survive the famine, and their association with the regime through their collective struggle for food, were important factors that strengthened Soviet resilience. [ABSTRACT FROM AUTHOR]

For species maintaining long-term social bonds, particularly in complex networks such as dense colonies, vocal cues to identity can be crucial. Here, we investigated the vocal individuality within and across five call types of the little auk: a monogamous, colonial bird with a strong nest fidelity. Calls produced inside the nest over the incubation period were recorded in 2019 and 2020 and assigned to a call type and individual. We extracted a set of 16 acoustic parameters for each vocalization, and seven additional temporal patterns for a complex, multisyllable call. Calls could be reliably assigned to an individual both within and across call types, although classification performance differed between linear and machine learning methods. All call types showed information content theoretically allowing us to distinguish at least 11 individuals, and up to at least 41 for the classic call. The raw acoustic parameters that contributed most information across the five call types (i.e. the five highest potential of individuality coding scores) were peak fundamental frequency, frequency value at the upper limit of the second and first quartiles of energy, sound duration and amplitude modulation rate. We suggest that this strong individuality across call types and parameters is selected for in the species to help maintain monogamous partnerships, and perhaps social bonds with neighbours, over the years. • Little auks are very colonial seabirds with strong partner and nest fidelity. • We investigated identity coding in vocalizations of 29 known individuals. • Calls could be reliably assigned to individuals within and across call types. • Their information content allowed distinction up to 41 individuals. • Parameters with the highest PIC covered time, frequency and amplitude domains. [ABSTRACT FROM AUTHOR]

The child-like question of why birds sing in the morning is difficult to answer, especially in polar regions. There, in summer animals live without the time constraints of daylight, and little is known about the rhythmicity of their routines. Moreover, in situ monitoring of animal behavior in remote areas is challenging and rare. Here, we use audio data from Greenland to show that a colony of a key Arctic-breeding seabird, the little auk (Alle alle), erupts with acoustic excitement at night in August, under the midnight sun. We demonstrate that the acoustic activity cycle is consistent with previous direct observations of the feeding and attendance patterns of the little auk. We interpret this pattern as reflecting their foraging activities, but further investigation on fledging and predators is needed. The study demonstrates that acoustic monitoring is a promising alternative to otherwise demanding manual observations of bird colonies in remote Arctic areas. Microphone data from Greenland suggest that a colony of a key Arctic-breeding seabird, the little auk, bursts with acoustic excitement at night, under the midnight sun. The study highlights that acoustics is a promising monitoring tool. [ABSTRACT FROM AUTHOR]

This article explores the complexities and conflicting terminologies surrounding the study of avian moult. It discusses two main nomenclatures, the 'life-cycle' system and the Humphrey-Parkes or 'H-P' system, and argues for a standardized and globally applicable terminology based on scientific evidence. The text also delves into the different patterns of molting in bird species, such as preformative molt and simultaneous molt, and discusses the evolution of molting patterns in different bird groups. It concludes that molting patterns have evolved multiple times within the passerine group, with the simultaneous alternate molt being more common in migratory and resident species in harsh habitats. [Extracted from the article]

The genus of honeypot ants MyrmecocystusWesmael, 1838 (Hymenoptera: Formicidae) is in the subfamily Formicinae and has 29 described species exclusively from North America, of which 16 are native to the Baja California Peninsula of Mexico. The genus includes mainly arid-adapted species found in habitats such as semi-deserts or coastal dunes. We present a new species, Myrmecocystus baja n. sp., which is morphologically similar to M. intonsus but has less pilosity and a dark reddish head. In addition to diagnostic morphological characters, we also provide evidence based on molecular data, which confirms veracity and distribution of the new species. A Bayesian phylogeny is based on the mitochondrial Cytochrome Oxidase subunit I (COI) gene of the new species, as well as other species of the genus, and shows that individuals from coastal dunes between latitudes 30.5 and 26.5°N form a monophyletic group representing the new species herein described. Additionally, we provide information on nest and colony structure of Myrmecocystus baja n. sp., notably the absence of replete workers, which the genus is known for. In conclusion, Myrmecocystus baja n. sp. is endemic to Baja California and adapted to living in coastal dunes of the Pacific Coast. El género de hormigas mieleras MyrmecocystusWesmael, 1838 (Hymenoptera: Formicidae) pertenece a la subfamilia Formicinae y tiene 29 especies descritas exclusivamente de Norteamérica, de las cuales 16 son nativas de la Península de Baja California en México. El género incluye principalmente especies adaptadas a zonas áridas que se encuentran en hábitats como semidesiertos o dunas costeras. Presentamos una nueva especie, Myrmecocystus baja n. sp., que es morfológicamente similar a M. intonsus pero tiene menos pilosidad y una cabeza de color rojizo oscuro. Además de los caracteres morfológicos diagnósticos, también proporcionamos evidencia basada en datos moleculares, que confirma la veracidad y distribución de la especie nueva. Una filogenia bayesiana basada en el gen mitocondrial citocromo oxidasa C subunidad I de la (COI) de la nueva especie, así como de otras especies del género, muestra que los individuos de las dunas costeras entre las latitudes 30.5 y 26.5°N forman un grupo monofilético que representa la especie nueva aquí descrita. Además, brindamos información sobre la estructura de nidos y colonias de Myrmecocystus baja n. sp., en particular la ausencia de obreras repletas, características de este género. En conclusión, Myrmecocystus baja n. sp. es endémica de Baja California y está adaptada a vivir en las dunas costeras de la Costa del Pacífico. [ABSTRACT FROM AUTHOR]

Based on camera trap images, we document active foraging attempts on nests of colonial waterbirds by a fishing cat Prionailurus viverrinus. The nests were built in the canopy of an 8-m-tall Indian Oak tree Barringtonia acutangula in the Haor Basin region, northeast Bangladesh. In 2022, two events of fishing cats reaching nests with fledglings were documented. In one event, the cat killed four fledglings. The species primarily follows a piscivorous diet and is evolutionarily adapted for semi-aquatic hunting niches. These records provide the first known evidence of the arboreal hunting behaviour observed in the fishing cat. [ABSTRACT FROM AUTHOR]

Interspecific foraging associations (IFAs) are biological interactions where two or more species forage in association with each other. Climate‐induced reductions in Arctic sea ice have increased polar bear (Ursus maritimus) foraging in seabird colonies, which creates foraging opportunities for avian predators. We used drone video of bears foraging within a common eider (Somateria mollissima) colony on East Bay Island (Nunavut, Canada) in 2017 to investigate herring gull (Larus argentatus) foraging in association with bears. We recorded nest visitation by gulls following n = 193 eider flushing events from nests during incubation. The probability of gulls visiting eider nests increased with higher number of gulls present (β = 0.14 ± 0.03 [SE], p <.001) and for nests previously visited by a bear (β = 1.14 ± 0.49 [SE], p <.02). In our model examining the probability of gulls consuming eggs from nests, we failed to detect statistically significant effects for the number of gulls present (β = 0.09 ± 0.05 [SE], p <.07) or for nests previously visited by a bear (β = −0.92 ± 0.71 [SE], p <.19). Gulls preferred to visit nests behind bears (χ2 = 18, df = 1, p <.0001), indicating gulls are risk averse in the presence of polar bears. Our study provides novel insights on an Arctic IFA, and we present evidence that gulls capitalize on nests made available due to disturbance associated with foraging bears, as eiders disturbed off their nest allow gulls easier access to eggs. We suggest the IFA between gulls and polar bears is parasitic, as gulls are consuming terrestrial resources which would have eventually been consumed by bears. This finding has implications for estimating the energetic contribution of bird eggs to polar bear summer diets in that the total number of available clutches to consume may be reduced due to avian predators. [ABSTRACT FROM AUTHOR]

Adélie penguins are considered indicators of Antarctic ecosystems. Their populations have declined by more than 50% in the West Antarctic Peninsula, an area strongly affected by global warming, and that concentrates most of Antarctic krill harvesting. The use of high-resolution data to identify foraging areas regularly used by krill predators could provide valuable information for current discussions on the development of small-scale management and conservation measures for this region. We used information on the foraging trips of 57 individuals breeding in King George Island, tracked over 2019/2020, 2020/2021 and 2021/2022 breeding seasons during the chick-rearing stage, to identify their key foraging areas. Using an accelerometry-based latent behavioral analysis approach, we identified an area within 10 km of the colony consistently used by over 60% of the population throughout and between seasons. We also observed that almost 20% of the population uses the area near a seamount located 35 km from the colony for foraging, mainly during the late guarding phase when chick energy demands are highest or the effects of prey depletion might become more evident. The distances and duration of trips and the area explored increased as the season progressed and varied between seasons, consistent with annual differences in krill availability observed in the region. Foraging dives comprise roughly 40% of the dives performed during foraging trips, irrespective of the stage of the chick-rearing period, or the season analyzed. Our results emphasize the need to understand how variability in environmental conditions, prey availability, and energetic demands affect how predators use space, and the role that bathymetric features might play in providing reliable foraging grounds, for penguins, in a rapidly changing region. [ABSTRACT FROM AUTHOR]

The grey heron is an extensively studied and widely distributed colonial bird species in the Old World; however, relevant information on the role played by vocalisations during the life cycle of individuals is still lacking. This research aimed to deepen the available knowledge on the repertoire and vocal behaviour of adults during the breeding season, through a bioacoustic approach and choosing as study areas two heronries in different environmental contexts. Colonies were monitored 2 days a week each, for 9 weeks, from 8:00 am to 6:00 pm (360 hr of sampling). Results showed that adults use a wide range of call types, mainly related to courtship and the reproductive phase. Vocalisations are emitted especially by males and are a key element during mate attraction, nest building, in breeding events and in strengthening bonds within pairs. Most vocalisations are expressed in the first weeks of the breeding cycle, concurrently with the maximum number of courtship males, which exhibit most of the detected sound categories and emit calls with lower frequencies than females. Moreover, these vocalisations are expressed to a greater extent in the heronry characterized by an important forest component, where an almost entirely exclusive sound category was detected. In conclusion, the results suggest a possible correlation between vocal behaviour and female choice. The wide variety of sound signals and the high rate of calls produced by males during attraction and courtship displays, together with the acoustic characteristics of the signals, could provide honest estimates of the quality of emitters. [ABSTRACT FROM AUTHOR]

Animal vocalisations can often inform conspecifics about the behavioural context of production and the underlying affective states, hence revealing whether a situation should be approached or avoided. While this is particularly important for socially complex species, little is known about affective expression in wild colonial animals, and even less to about their young. We studied vocalisations of the little auk (Alle alle) chicks in the Hornsund breeding colony, Svalbard. Little auks are highly colonial seabirds, and adults convey complex behavioural contexts through their calls. We recorded chick calls during two contexts of opposite affective valence: handing by a human, and while they interact with their parents inside the nest. Using permuted discriminant function analysis and a series of linear mixed models, we examined the effect of the production context/associated affective valence on the acoustic parameters of those calls. Calls were reliably classified to their context, with over 97% accuracy. Calls uttered during handling had higher mean entropy, fundamental frequency, as well as lower spectral centre of gravity and a less steep spectral slope compared to calls produced during interactions with a parent inside the nest. The individuality of handling calls, assessed by information content, was lower than the individuality of calls uttered in the nest. These findings suggest that seabird chicks can effectively communicate behavioural/affective contexts through calls, conveying socially important messages early in development. Our results are mostly in line with emotional expression patterns observed across taxa, supporting their evolutionary continuity. [ABSTRACT FROM AUTHOR]

Aerial images obtained by drones are increasingly used for ecological research such as wildlife monitoring. Yet detectability issues resulting from animal activity or visibility are rarely considered, although these may lead to biased population size and trend estimates. In this study, we investigated detectability in a census of Malagasy pond heron Ardeola idae colonies on the island of Mayotte. We conducted repeated drone flights over breeding colonies in mangrove habitats during two breeding seasons. We then identified individuals and nests in the images and fitted closed capture-recapture models on nest-detection histories. We observed seasonal variation in the relative abundance of individuals, and intra-daily variation in the relative abundance of individuals—especially immature birds—affecting the availability of nests for detection. The detection probability of nests estimated by capture–recapture varied between 0.58 and 0.74 depending on flyover days and decreased 25% from early to late morning. A simulation showed that three flyovers are necessary to detect a 5–6% decline in colonies of 50 to 200 nests. These results indicate that the detectability of nests of forest-canopy breeding species from airborne imagery can vary over space and time; we recommend the use of capture-recapture methods to control for this bias. [ABSTRACT FROM AUTHOR]

Predation by Caspian terns Hydroprogne caspia is a factor limiting the recovery of some Endangered Species Act‐listed populations of salmonids from the Columbia River basin, especially steelhead Oncorhynchus mykiss. This prompted the development and implementation of two separate management plans, one in the Columbia River estuary and the other in the Columbia Plateau region, to reduce the impact of Caspian tern predation on smolt survival. Caspian terns nesting at managed breeding colonies within the basin were relocated to alternative nesting islands created for terns outside the basin. Both plans were successful in significantly reducing smolt losses to Caspian terns nesting at managed sites; however, new developments have led to regression in smolt survival gains associated with tern management. Adaptive management to prevent terns at managed colonies from relocating to nest elsewhere in the basin and to improve nesting opportunities for Caspian terns outside the basin are needed to maximize the survival benefits to Endangered Species Act‐listed salmonids from management. Adaptive management is also necessary to ensure the long‐term viability of the Pacific Flyway population of Caspian terns, whose breeding population has declined by more than 50% since the two management plans were implemented. [ABSTRACT FROM AUTHOR]

Marine debris from fishing-related paraphernalia poses a threat to the survival of marine organisms, especially seabirds. Although the detrimental effects of marine debris on seabirds have been documented, studies on the extent of damage inflicted by marine debris on the seabird breeding population are scarce. Here, marine debris ingestion and entanglement damage to black-tailed gulls (Larus crassirostris) residing in South Korea were quantified. The five breeding colonies of black-tailed gulls were visited, and the frequency of ingestion and entanglement damage in adults and young were recorded. A total of 25 cases of marine debris damage were confirmed. As a result, damage by marine debris to gulls varied depending on breeding colonies. More adults suffered from entanglement damage than the young, and their most damaged parts were usually their legs. Fishing lines and hooks caused the most damage. We suggest that marine debris damage acquired in breeding colonies could affect breeding success. [ABSTRACT FROM AUTHOR]

The eradication of rats (Rattus norvegicus, R. exulans and R. rattus) on islands is essential for the preservation of island ecosystems, including seabird populations, which are particularly vulnerable to rat predation. However, the long‐term positive effects of rat eradication on seabird colonies and populations are often understudied. Brown rats (R. norvegicus) were eradicated from Tromelin Island in 2005. No other significative active restoration actions (such as artificial social attraction, translocation or habitat manipulations) have been implemented, which provides a unique opportunity to investigate natural seabird recolonization and recovery processes after rat eradication. We used seabird annual nest counts conducted from 2005 to 2022 and georeferenced data of occupied nests, to precisely describe the rebuilding of the seabird community of Tromelin Island. Despite the lack of any active restoration actions after the eradication of rats, and the remoteness of the island, 17 years after rat eradication, the seabird community increased from two to seven breeding species, and from 353 to 4758 breeding pairs (total for all species). The recovery of masked and red‐footed booby populations was mostly due to the improved breeding success and in fine to auto‐recruitment. Inter‐ and intra‐specific social attraction accelerated the arrival of new species and boosted their population growth. On a finer spatial scale, recolonizing species showed different patterns of colony settlement linked to intra‐specific attraction. The dynamics of the community of Tromelin Island after rat eradication can be regarded as a natural experiment that informs the processes of colony settlement, population dynamics and connectivity in tropical seabirds. Our results demonstrate the huge benefits of eradicating rats from seabird islands, even when no additional active restoration actions are feasible. [ABSTRACT FROM AUTHOR]

Bioaccumulation and biomagnification of anthropogenic particles are crucial factors in assessing microplastic impacts to marine ecosystems. Microplastic pollution poses a significant threat to iconic and often endangered species but examining their tissues and gut contents for contaminant analysis via lethal sampling is challenging due to ethical concerns and animal care restrictions. Incorporating empirical data from prey items and fecal matter into models can help trace microplastic movement through food webs. In this study, the Galápagos penguin food web served as an indicator species to assess microplastic bioaccumulation and biomagnification potential using trophodynamic Ecopath with Ecosim (EwE) modelling with Ecotracer. Empirical data collected from surface seawater near Galápagos penguin colonies, zooplankton, penguin prey, and penguin scat in October 2021 were used to inform the ecosystem model. Multiple scenarios, including a 99% elimination rate, were employed to assess model sensitivity. Model predictions revealed that microplastics can bioaccumulate in all predator-prey relationships, but biomagnification is highly dependent on the elimination rate. It establishes the need for more research into elimination rates of different plastics, which is a critical missing gap in current microplastic ecotoxicological and bioaccumulation science. Compared to empirical data, modelling efforts underpredicted microplastic concentrations in zooplankton and over-predicted concentrations in fish. Ultimately, the ecosystem modelling provides novel insights into potential microplastics' bioaccumulation and biomagnification risks. These findings can support regional marine plastic pollution management efforts to conserve native and endemic species of the Galápagos Islands and the Galápagos Marine Reserve. [ABSTRACT FROM AUTHOR]

This study presents the results of a systematic survey of La Pastosa Islet, located 700 m off the west coast of Río Negro, Argentina. This small islet has the particularity of hosting the northernmost colony of Magellanic penguins (Spheniscus magellanicus) to date and contains evidence of its use by hunter-gatherer groups during the late Holocene. This growing colony started around 2002 and has had a significant impact on the subsurface archeological record of the islet by increasing erosion and exposing buried materials through nest excavation, particularly lithic artifacts. The spatial analysis of the distribution of artifact and penguin burrows indicates that the actions of the latter generated a "snapshot" of the subsurface distribution of the lithic record. The observed distribution suggested higher discard rates at the center of the islet. Furthermore, this study shows the synergy between both types of records in the formation dynamics of the lithic landscape and the agency of penguins as active landscape engineers. Finally, the obtained results have important implications for the management of the protected sector of the recently established Islote Lobos National Park, within which the study area is located. [ABSTRACT FROM AUTHOR]

Aim: To analyse the role of non‐frugivorous birds on seed dispersal, seed dispersal by gulls is expected to be especially instrumental in island ecosystems, as these have a smaller subset of frugivores when compared to the mainland, and because long‐distance dispersal is required for plant colonisation. Here, we investigated the seed dispersal of olives by gulls among 10 islands of the same archipelago to reveal if gulls contribute to long‐distance seed dispersal including different islands, and how gulls' adaptation to domestic olives and individual differences in foraging activities affect their seed dispersal pattern. Location: Balearic Islands in the Western Mediterranean Sea, Spain. Taxon: Yellow‐legged gulls (Larus michahellis), Domestic and wild Olives (Olea europaea and O. europaea var. sylvestris). Methods: We developed seed dispersal models of the two ecotypes of olives dispersed by gulls across an archipelago, based on GPS tracking data, gut passage time and seed viability. Results: Mean dispersal distances were 7.67 (±12.48) km in wild and 12.57 (±13.08) km in domestic olives. 7.1% of wild and 8.5% of domestic olives were dispersed among islands. Among these, 8.2% of domestic seeds were transported from large to small islands where gull colonies are located, whereas wild olives were dispersed in more variable directions. Such dispersal pattern of two olive ecotypes was consistent despite the differences in dispersal distances among individuals. Main Conclusions: Gulls contributed to long‐distance olive seed dispersal including different islands. The seed dispersal of domestic olives to longer distances with specific directions may facilitate colonisation and expansion of that variant if the conditions of seed deposition sites are suitable. Our findings indicate that gulls are relevant vectors for long‐distance dispersal of large fleshy fruits in island ecosystems where specialist large frugivores are absent. [ABSTRACT FROM AUTHOR]

I documented the number of active nests of Petrochelidon pyrrhonota (Cliff Swallow) at 20 colony sites along or near the Great Pee Dee River (GPDR) corridor in the lower Piedmont of North Carolina and Coastal Plain of South Carolina in 2012. I again monitored active colonies in this area from 2016 to 2018 and in 2022. Cliff Swallows continued to breed primarily at bridges and other water-based anthropogenic sites (23 of 29; 79%) and some land-based sites, but abandoned a highway overpass site. Numbers of active nests at the same 20 colony sites over the 5 years during early to mid-May fluctuated from 1862 in 2016, the only year when the number of active nests exceeded those in 2012, to 1050 in 2018. Number of active nests at colony sites decreased by 18% between 2012 and 2022. Nesting populations at colony sites have decreased within the GPDR corridor in North Carolina, where 6 radial colony sites near the GPDR were abandoned by 2022. In contrast, nesting populations within the GPDR corridor in the Coastal Plain of South Carolina have remained stable, but 8 new colony sites were detected, including 1 site near the coast. In the Middle Atlantic Coastal Plain of southeastern North Carolina, rapid expansion of colony sites has occurred in tidewater regions or near the coast, but the size of 3 colony sites closest to South Carolina (85 km) were small. The main source of Cliff Swallow colony dispersal and expansion of colony sites into coastal regions of South Carolina will likely be from within the GPDR corridor and other areas in the interior of the northeastern Coastal Plain of South Carolina, despite the increasing number of colony sites in the Middle Atlantic Coastal Plain of North Carolina. [ABSTRACT FROM AUTHOR]

The village weaver (Ploceus cucullatus) is a common colonial nesting bird widespread throughout Sub-Saharan Africa. It is known to weave its nests from leaf strips from a variety of tree species (mainly coconuts trees, oil palm trees) associated with human settlement areas, grasses, and other available plants. In this regard, this bird was considered a pest for its impact on different economic activities. Although extensive literature is already available on the parasitic role of village weavers, there is still a lack of analytical data that outlines which tree species are used for nesting and in what proportion, as well as the related implications in terms of economic impacts. Here, we carried out the first comprehensive arrangement of trees used by this species for nesting in Southern Nigeria (West Africa), checking for possible different impacts on stakeholders. In April 2021, we searched for village weaver nesting in 95 sites in 77 communities from 24 local government areas in Southern Nigeria, during 14 field surveys. Within each site, we collected GPS coordinates and counted the number of active nests, nesting birds and occupied trees. We recorded a total of 5,776 nests and 2,140 birds in 94 plants belonging to 23 tree species selected for nesting. Oil palm (Elaeis guineensis; n = 45) was the most used tree species, as 2,990 (51.77%) nests and 873 (40.79%) birds were recorded. Our results indicate the preference for nesting on trees used by stakeholders belonging to agricultural (palm farmers), touristic (operators) and energy (gas flare stations) sectors with economic implications about the conflict with this pest species. [ABSTRACT FROM AUTHOR]

The structure and numbers of the urban population of the tufted duck (Aythya fuligula) in Moscow were studied. Wintering birds over 36 seasons, 1985−2021, on ice-free water bodies, as well as females with broods and the number of ducklings in each brood for 24 seasons, 1998−2021, on 150 ponds and 23 rivers of Moscow were counted. The date of the onset of egg-laying by females was calculated using the countdown method, based on the age of ducklings. The size of the wintering group from 1985 to 2009 averaged 32 (1–75) birds. This number increased to an average of 174 (111–332) birds for the period 2010–2021. The number of nesting females with broods changed from 11 to 45, with an average of 27 broods occurring annually. The size of the wintering group correlated with the length of the frosty period and with the average daily November and December air temperature, as in the case of mallards and goldeneyes. The winter abundance of tufted ducks correlated with the adult females number in the following summer. The similarity of the tufted duck, goldeneye, and mallard breeding cycles is in ordering the onset of egg-laying to the transition of the average daily air temperature over 0°C. The earlier positive temperatures are established and the earlier the ice melts, the more time the females had for getting prepared for egg-laying. In summer, the number of adult ducks, broods, and ducklings increased from 1998 to 2009. The number of broods and ducklings decreased, and the number of adult birds did not change significantly from 2010 to 2021. The ratio of the number of young and adult birds decreased during the observation period. In the population of the tufted duck, the consequences of overcrowding were manifested to a lesser extent than in the mallard. They are the lengthening of the egg-laying period and the reduction in the brood-size related to an increase in the females number. The dynamics of the spatial distribution of nesting tufted ducks in Moscow at the early stages was determined by the distribution of colonies of black-headed gulls, with which they formed joint settlements. Subsequently, this dependence weakened. [ABSTRACT FROM AUTHOR]

The results of a comparison of the long-term population dynamics of seabirds breeding in the western part of the White Sea on both protected and unprotected islands are presented. A series of observations was conducted for more than 50 years in the Kandalaksha Nature Reserve and for more than 30 years in the Solovetskii Archipelago. The dynamics of the breeding part of the population were analyzed for six species occurring in both study areas. The population trends of the common eider Somateria mollissima, the European herring gull Larus argentatus, and the black guillemot Cepphus grylle, were the same in the two areas, while those of the Eurasian oystercatcher Haematopus ostralegus, the common gull Larus canus, and the ruddy turnstone Arenaria interpres differed. The uniform trends are due to similar natural conditions of the breeding and wintering grounds of the birds in the Solovetskii Archipelago and Kandalaksha Bay. The discrepancies are mostly associated with different protection regimes on the islands used for breeding, as well as with an increased pressure of both terrestrial and avian predators on seabird colonies in recent decades. [ABSTRACT FROM AUTHOR]

The Antarctic Peninsula has been rapidly warming, resulting in changes to the abundance and surface cover of terrestrial aquatic ecosystems, as well as their ecosystem structure and function. Therefore, comparative studies of aquatic ecosystems across large latitudinal gradients can be useful in better understanding these changes and making more reliable predictions regarding the consequences of climate change. During Turkish Antarctic Expeditions in 2018 and 2019, samples were collected from 10 lakes and 3 ponds across Maritime Antarctica (north-western coasts of the Antarctic Peninsula). These lakes and ponds were located on Ardley, Robert, Livingstone, Galindez, and Horseshoe islands, covering a latitudinal gradient of over 800 km. Snapshot samplings were conducted of the water chemistry, including nutrient, major ion, and trace metal concentrations, as well as pigment compositions representing the primary productivity and plankton community composition. These lakes and ponds had large variations in nutrient concentrations (0.8-771 μg/L PO4 and 30-886 μg/L total dissolved inorganic N) and conductivity (30-735 μS), representing a trophic status ranging from ultra-oligotrophic to a few eutrophic sites (for example a pond near penguin colonies). The total productivity, measured as the chlorophyll-a (Chl-a) level, was generally low (0.02-3.2 μg/L) in the lakes, reflecting their oligotrophic characteristics. However, the composition of pigments in the water column showed significant variation across the lakes. Both the patterns in the total Chl-a concentrations and pigment compositions reflected the patterns in conductivity and nutrient gradients across the lakes. Overall, the observed patterns suggested a predominant role of nutrient transport from the sea in driving the chemical composition and primary productivity of Antarctic lakes, mediated by the distance to the sea, as well as the activities of seals and penguin colonies. [ABSTRACT FROM AUTHOR]

This paper advocates the use of compositional specifications based on formal languages as a means of modelling and analysing sophisticated collective behaviour in natural systems. With the use of appropriate linguistic constructs, models can be developed that are both compact and intuitive, and can be easily refined and extended in small steps. Automated workflows can be implemented on top of this methodology to provide quick feedback, enabling rapid design iterations. To support our argument, we present three examples from the natural world, focusing on flocks of birds and colonies of ants, which feature well-known examples of emergent behaviour in collective adaptive systems. We use an agent-based language to develop simple models that aim at capturing these collective phenomena, and discuss the specific language constructs that we use in the process. Then, we adapt an existing verification tool for the language to simulate our models, and show that our simulations do display emergent behaviour. [ABSTRACT FROM AUTHOR]

Data on the influence that grey heron (Ardea cinerea L., 1758) colonies have on the dynamics of tree ring parameters in pine plantations are presented. It is shown that the beginning of the stands colonisation by the grey heron can be quite accurately determined by analysing the dynamics of the annual tree rings parameters, especially the width of their late layer and the optical density of wood (the values of the former are lower in the control stand, and of the latter one are higher there). Grey heron colonies begin to appear in pine forests as early as 10–12 years old, when the height of the trees reaches 5–6 m, and the diameter of the trunk at a height of 1.3 m from the soil surface is only 7–8 cm. In the first 15–20 years, they have a positive influence on the annual growth of trees, especially on the width of the late layer of wood and the thickness of the cell walls, but then the picture changes to the opposite. The total residence time of heron colonies in one place is about 35–40 years, after which they move to new places due to the forest stands coming into disarray or even facing complete destruction. To reduce the likelihood of the appearance of grey heron colonies, which in many cases have a negative impact on the state of forest biogeocoenoses, it is necessary to stop creating pure pine forests near water bodies, giving preference to spruce, birch, poplar, or linden-oak plantations. [ABSTRACT FROM AUTHOR]