Species-environment relationships were studied between the occurrence of 13 fish and lamprey species and 9 mainly map-based environmental variables of Finnish boreal small streams. A self-organizing map (SOM) analysis showed strong relationships between the fish species and environmental variables in a single model (explained variance 55.9%). Besides basic environmental variables such as altitude, catchment size, and mean temperature, landcover variables were also explored. A logistic regression analysis indicated that the occurrence probability of brown trout, Salmo trutta L., decreased with an increasing percentage of peatland ditch drainage in the upper catchment. Ninespine stickleback, Pungitius pungitius (L.), and three-spined stickleback, Gasterosteus aculeatus L., seemed to benefit from urban areas in the upper catchment. Discovered relationships between fish species occurrence and land-use attributes are encouraging for the development of fish-based bioassessment for small streams. The presented ordination of the fish species in the mean temperature gradient will help in predicting fish community responses to climate change.

1. Teleost fishes occupy a range of ecosystem and habitat types subject to large seasonal fluctuations. Temperate fishes in particular, survive large shifts in temperature, light availability, and access to certain habitats across seasons. Yet, there is limited understanding of how behavioral responses to a seasonally shifting environment might shape, or be shaped by, the nervous system. 2. Here we quantified variation in relative brain size and the size of five externally visible brain regions in a freshwater top predator, lake trout (Salvelinus namaycush), across six consecutive seasons in two different lakes. Acoustic telemetry data from one of our study lakes was collected during the study period from a different subset of individuals and used to infer relationships between brain size and seasonal behaviors (habitat use and movement rate). 3. Our results indicated that lake trout relative brain size was larger in the fall and winter compared to the spring and summer in both lakes. Larger brains coincided with increased use of nearshore lake habitats and increased horizontal movement rates by lake trout in the fall and winter based on acoustic telemetry. The telencephalon followed the same pattern as whole brain size, while the other brain regions (cerebellum, optic tectum, olfactory bulbs, hypothalamus) were only smaller in the spring. 4. Seasonal shifts in total brain size might reflect greater underlying changes in the size of the telencephalon. These findings provide evidence that flexibility in brain size could underpin shifts in behavior which could subserve functions associated with differential habitat use during cold and warm seasons and allow fish to succeed in seasonally variable temperate environments.

Longevity is highly variable among animal species, and has coevolved with other of life-history traits, like body size and rates of reproduction. Telomeres, through their erosion over time, are one of the cell mechanisms that produce senescence at the cell level, and might even have an influence on the rate of ageing in whole organisms. However, uneroded telomeres are also risk factors of cell immortalization. The associations of telomere lengths, their rate of change, and life-history traits independent of body size are largely underexplored for birds. To test associations of life-history traits and telomere dynamics, we conducted a phylogenetic meta-analysis using studies of 53 species of birds. We restricted analyses to studies that applied the telomere restriction fragment length (TRF) method, and examined relationships between mean telomere length at the chick (Chick TL) and adult (Adult TL) stages, the mean rate of change in telomere length during life (TROC), and life-history traits. We examined 3 principal components of 12 life-history variables that represented: body size (PC1), the slow-fast continuum of pace-of-life (PC2) and post-fledging parental care (PC3). Phylogeny had at best a small-to-medium influence on Adult and Chick TL (r² = 0.190 and 0.138, respectively), but a substantial influence on TROC (r² = 0.688). Phylogeny strongly influenced life histories: PC1 (r² = 0.828), PC2 (0.838), and PC3 (0.613). Adult TL and Chick TL were poorly associated with the life-history variables. TROC, however, was negatively and moderate-to-strongly associated with PC2 (unadjusted r = -0.340; with phylogenetic correction, r = -0.490). Independent of body size, long-lived species with smaller clutches and slower embryonic rate of growth may exhibited less change in telomere length over their lifetimes. We suggest that telomere lengths may have diverged even among closely avian related species, yet telomere dynamics are strongly linked to the pace of life.

The assessment of wildlife population sizes and their trends is one of the most important research fields in conservation biology, as it is used to identify vulnerability soon enough to implement measures in threatened species, or to set up sustainable harvesting rates in exploited populations. Yet, because field work is expensive, may be difficult in terms of logistics and because some populations of the same species may be monitored by different stakeholders, population status often rely on fragmented and heterogenous information on sub-populations collected through various monitoring programs. In this context, data integration, i.e. the simultaneous analysis of different datasets in a single modelling framework allows to get unbiased and more precise trend estimates than separated analysis that in turn may lead to more adequate management policies. In this study we developed an integrated state-space model to jointly model populations growth rates from individual counts and hunting bags data for three hunted species of mountain Galliformes in Italy. We examined population trends at various spatial scales and disentangled the potential effect of game management plans from biological factors. The integration of counts and bags succeeded in improving growth rate parameter precision and in reducing proxy-specific bias by increasing the sample size and extending data series length. On a 19-year basis, all three species exhibited negative mean growth rates. We did not find strong regional patterns for Rock ptarmigan and Rock partridge, as a likely consequence of prevailing effects of local environmental conditions on population growth rate. Black grouse eastern populations exhibited lower growth rate than western populations. Our paper demonstrates that an integrated model of different index of population size of game species can provide more accurate values than separate analysis, we advocate to consider such an approach for other wildlife monitoring cases for which data is scarce.

The construction of morphological character matrices is central to paleontological systematic study, which extracts paleontological information from fossils. Although the word information has been repeatedly mentioned in a wide array of paleontological systematic studies, its meaning has rarely been clarified and there has not been a standard to measure paleontological information due to the incompleteness of fossils, difficulty of recognizing homologous and homoplastic structures, etc. Here, based on information theory, we show the deep connections between paleontological systematic study and communication system engineering. It is information, the decrease of uncertainty, in morphological characters that distinguishes operational taxonomic units (OTUs) and reconstructs evolutionary history. We propose that concepts in communication system engineering such as source coding and channel coding correspond in paleontological studies to the construction of diagnostic features and the entire character matrices, which should be distinguished as how typical communication systems are engineered because these two steps serve dual purposes. With character matrices from six different vertebrate groups, we analyzed their information properties including source entropy, mutual information, and channel capacity. Estimation of channel capacity shows upper limits of all matrices in transmitting paleontological information, indicating that, due to the presence of noise, too many characters not only increase the burden in character scoring, but also may decrease quality of matrices. Information entropy, which measure how informative a variable is, of each character is tested as a weighting criterion in parsimony-based systematic studies, the results show high consistence with existing knowledge with both good resolution and interpretability.

Global climate change poses major challenges for current biodiversity conservation efforts. Assessing species’ vulnerability to climate change is a prerequisite for developing effective strategies to reduce emerging climate-related threats. We used the maximum entropy algorithm (MaxEnt model) to assess potential changes in snow leopard (Panthera uncia) suitable habitat in Qinghai Province, China under a mild climate change scenario. Our results showed that the area of snow leopard suitable habitat in Qinghai Province was 302,821 km2 under current conditions and 228,997 km2 under 2050’s climatic scenario, and that its mean elevation would shift upward 90 m. At present, nature reserves protect 38.78% of the currently suitable habitat and will protect 42.56% of future suitable habitat. Current areas climate refugia amounted to 212,341 km2, mainly distributed in Sanjiangyuan, Qilian mountains and surrounding areas. Our results provide valuable information for formulating strategies to meet future conservation challenges brought on by climate stress. We suggest that conservation efforts in Qinghai Province should focus on protecting areas of climate refugia and on maintaining or building corridors when planning for future species management.

Rapidly changing climate is likely to modify the spatial distribution of both flora and fauna. Land use change continues to alter the availability and quality of habitat and further intensifies the effects of climate change on wildlife species. We used an ensemble modelling approach to predict changes in habitat suitability for an iconic wildlife species, greater one-horned rhinoceros due to the combined effects of climate and land use changes. We compiled an extensive database on current rhinoceros distribution and selected nine ecologically meaningful environmental variables for developing ensemble models of habitat suitability using seven different species distribution modelling techniques in the BIOMOD2 R package; and we did this under current climatic conditions and then projected them onto two possible climate scenarios (SSP1-2.6 and SSp5-8.5) and two different time frames (2050 and 2070). Out of seven algorithms, random forest performed the best, and four environmental variables — distance from grasslands, distance from wetlands, annual precipitation, and slope, contributed the most in the model. The ensemble model estimated the current suitable habitat of rhinoceros to be 1,875 km2, about 1.3% of the total area of Nepal. The future habitat suitability under the lowest and highest emission scenarios was estimated to be: (1) 1,637 km2 and 1,417 km2 in 2050; and (2) 1,562 km2 and 1,301 km2 in 2070, respectively. Our results suggest that nearly one-third of the current rhinoceros habitat would become unsuitable within a period of 50 years, with the predicted declines being influenced to a greater degree by climatic changes than land use changes. We have recommended several measures to moderate these impacts, including relocation of the proposed Nijgad International Airport given that a considerable portion of potential rhinoceros habitat will be lost if the airport is constructed on the currently proposed site.

Predation is the most common cause of nest failure in birds. While nest predation is relatively well studied in general, our knowledge is unevenly distributed across the globe and taxa, with for example limited information on shorebirds breeding in sub-tropics. Importantly, we know fairly little about the timing of predation within a day and season. Here, we followed 444 nests of red-wattled lapwings (Vanellus indicus), a ground-nesting shorebird, for a sum of 7828 days to estimate a nest predation rate, and continuously monitored 230 of these nests for a sum of 2779 days to reveal how the timing of predation changes over the day and season in a sub-tropical desert. We found that 312 nests (70%) hatched, 76 nests (17%) were predated, 23 (5%) failed for other reasons and 33 (7%) had an unknown fate. Daily predation rate was 0.95% (95%CrI: 0.76% – 1.19%), which for a 30-day long incubation period translates into ~25% (20% – 30%) chance of nest being predated. Such a predation rate is low compared to most other avian species. Predation events (N = 25) were distributed evenly across day and night, with a tendency for increased predation around sunrise. Predation rate and events were distributed evenly also across the season, although night predation was more common later in the season, perhaps because predators reduce their activity during daylight to avoid extreme heat. Indeed, nests were never predated when mid-day ground temperatures exceeded 45°C. Whether the diel activity pattern of resident predators undeniably changes across the breeding season and whether the described predation patterns hold for other populations, species and geographical regions awaits future investigations.

Also investigate how the potential distribution of this species changes with the addition of new records over the decades (decade effect). Assuming that (1: hypothesis of the effect of the decade) the addition of new occurrence records over time increases the potential size of the species distribution; and (2: Wallacean distance hypothesis) over the years, the new points added are increasingly distant from the research centers. Considering the geographic knowledge gap of Histiotu velatus, our objective is to report a new record of this species and estimate its potential distribution in South America through ENMs. For this, we compiled records of occurrence of species, selected from 1900 to 2015. We used 19 bioclimatic variables available in the WorldCLim database to estimate the potential distribution of the species and we used three modeling algorithms: Maximum Entropy (MXT) Random Forest (RDF) and Support Vector Machine (SVM). We selected the main bat research centers in Brazil, using the Lattes platform for the Wallacean distance hypothesis, using the Euclidean distance calculation. To test the hypothesis of the decade effect, we used beta regression analysis, taking conservative and non-conservative approaches. The results showed that the predicted area expanded and retracted over the decades, with an improvement in the accuracy of the models with the addition of new data. Most of the records are located in the southeastern region of Brazil, but the algorithms predicted areas in countries where there were no records. Only the conservatism approach has had a positive relationship over the decades. The distance from new points does not increase over the years of research centers.

Heterogeneity in the intrinsic quality and nutritional condition of individuals affects reproductive success and consequently fitness. Understanding differences in energy allocation towards survival and reproduction within and among years might help explain variability in individual fitness. Black brant (Branta bernicla nigricans) are long-lived, migratory, specialist herbivores. Long migratory pathways and short summer breeding seasons constrain the time and energy available for reproduction, thus magnifying life-history trade-offs. These constraints, combined with long lifespans and trade-offs between current and future reproductive value, provide a model system to examine the role of individual heterogeneity in driving life-history strategies and individual heterogeneity in fitness. We used hierarchical Bayesian models to examine reproductive trade-offs, modeling the relationships between within-year measures of reproductive energy allocation and among-year demographic rates of individual females breeding on the Yukon-Kuskokwim Delta, Alaska using capture-recapture and reproductive data from 1988 to 2014. We provide evidence for relationships between breeding probability and clutch size (posterior mean of β = 0.45, 95% CRI = 0.33 – 0.57, SD = 0.06), breeding probability and nest initiation date (posterior mean of β = -0.12, 95% CRI = -0.2 ¬– -0.04, SD = 0.04), and an interaction between clutch size and initiation date (posterior mean of β = -0.12, 95% CRI = -0.2 – -0.04, SD = 0.04). Average lifetime clutch size also had a weak positive relationship with survival probability (posterior mean of β = 0.03, 95% CRI = -0.01 – 0.7, SD = 0.02). Our results support the use of demographic buffering strategies for black brant; reductions in reproductive energy allocation preserve high adult survival rates during years with poor environmental conditions, maximizing future reproductive value. We also indirectly show links among environmental conditions during growth, fitness, and energy allocation, highlighting the effects of early growth conditions on individual heterogeneity, and subsequently, reproductive investment.

1. Stable isotopes represent a unique approach to provide insights into the ecology of organisms. δ13C and δ15N have specifically be used to obtain information on the trophic ecology and food web interactions. Trophic discrimination factors (TDF, Δ13C and Δ15N) describe the isotopic fractionation occurring from diet to consumer tissue and these factors are critical for obtaining precise estimates within any application of δ13C and δ15N values. It is widely acknowledged that metabolism influences TDF, being responsible for different TDF between tissues of variable metabolic activity (e.g. liver vs. muscle tissue) or species body size (small vs. large). However, the connection between the variation of metabolism occurring within a single species during its ontogeny and TDF has rarely been considered. 2. Here, we conducted a 9-month feeding experiment to report Δ13C and Δ15N of muscle and liver tissue for several weight classes of Eurasian perch (Perca fluviatilis), a widespread teleost often studied using stable isotopes, but without established TDF for feeding on a natural diet. In addition, we assessed the relationship between the standard metabolic rate (SMR) and TDF by measuring their oxygen consumption of the individuals. 3. Our results showed a significant negative relationship of SMR with Δ13C, and a significant positive relationship of SMR with Δ15N of muscle tissue, but not with TDF of liver tissue. SMR varies inversely with size, which translated into a significantly different TDF of muscle tissue between size classes. 4. In summary, our results emphasize the role of metabolism in shaping specific TDF (i.e. Δ13C and Δ15N of muscle tissue), and especially highlight the substantial differences between individuals of different ontogenetic stages within a species. Our findings thus have direct implications for the use of stable isotope data and the applications of stable isotopes in food web studies.

Recent findings suggest that immunosenescence should not be considered as a unidirectional deterioration, and that the remodeling of the immune system with age could also be adaptive. Longitudinal studies on immunosenescence in wild populations are scarce, and therefore, processes like selective disappearance cannot be easily torn apart from senescence. Using a long-term and longitudinal monitoring of a wild population of Alpine marmots, we aimed to understand within and between individual variation in the immune phenotype with age, in order to improve our knowledge about the occurrence and the consequence of immunosenescence in the wild. We tested, once controlled for a potential selective disappearance, whether individuals’ immune function only decreases as they age, as expected from the disposable soma theory, or whether remodelling of the immune system does occur. Therefore, we recorded the age-specific leukocyte concentration and counts in repeatedly sampled dominant individuals and we tested the potential changes with age as well as their association with survival probabilities. The overall leukocyte concentration was stable with age, but the lymphocyte count decreased, while the neutrophil count increased, over the course of an individual’s life. The leukocyte counts also predicted survival: at a given age, individuals with fewer lymphocytes but more neutrophils were more likely to die. Longitudinal studies, like the present one, are required to properly understand the patterns and consequences of immunosenescence in the wild.

Appendages have been reduced or lost hundreds of times independently during vertebrate evolution. This suggests that selection routinely favors appendage reduction. How often are the same developmental and genetic pathways used during loss by independent lineages? We reviewed the developmental and evolutionary literatures of appendage reduction in 12 genera spanning fish, reptiles, birds, and mammals. We found that appendage reduction and loss resulted from modified gene expression in each case but one. However, the genes for which expression was modified were rarely shared. Our findings suggest that adaptive loss of complex traits might proceed relatively easily through changes in gene expression along multiple developmental pathways.

Ecological context – the particular environment, and how it shapes mixing dynamics and individual susceptibility surrounding infectious disease events – can have major bearing on epidemic outcomes, yet directly comparable disease events with contrasting ecological contexts are relatively rare in wildlife systems due to concurrent differences in host genetics or pathogen strain. Here, we present a case study of one such event: a spillover of a “goat-clade” Mycoplasma ovipneumoniae strain into one bighorn sheep population that played out against two very different ecological backdrops. One event occurred on the herd’s home range near the Rio Grande Gorge in New Mexico, while the other progressed in a captive facility at Hardware Ranch in Utah. We collected data on antibody and pathogen load patterns through time at the individual level, and examined demographic responses to pathogen invasion to compare the intensity of, and in-host responses to, infection in both settings. While data collection regimens varied between the two sites, general patterns of antibody expansion and gross timing of symptoms were consistent. Symptoms emerged in the captive setting 12.9 days post-exposure, and we estimated an average time to seroconversion among the captive animals of 24.9 days. Clinical signs peaked among the captive animals at approximately 36 days post-infection, consistent with subsequent declines in symptom intensity in the free-ranging herd. At the captive site, older animals exhibited more severe declines in body condition as determined through declines in loin thickness, higher symptom burdens, and a decelerated antibody response to the pathogen. Younger animals were more likely than older animals to clear infection at or before the time of sampling at both sites. This study presents one of the richest datasets on immune responses in bighorn sheep over the course of a newly introduced M. ovipneumoniae strain available to-date.

There is evidence that prey can perceive the risk of predation and alter their behaviour in response, resulting in changes in spatial distribution and potential fitness consequences. Previous approaches to mapping predation risk quantify predator space use to estimate potential predator-prey encounters, yet this approach does not account for successful predator attacks resulting in prey mortality. An exception is a prey kill-site, which reflects an encounter resulting in mortality, but obtaining these data can be expensive and requires time to accumulate adequate sample sizes. We illustrate an alternative approach using predator scat locations and their contents to quantify spatial predation risk for elk (Cervus canadensis) from multiple predators in Alberta, Canada. We combined predictions of scat-based resource selection functions for bears (Ursus arctos/U. americanus), cougars (Puma concolor), coyotes (Canis latrans), and wolves (C. lupus) based on scat-detection dog surveys with predictions for the probability that a predator-specific scat in a location contained elk. We evaluated our approach by comparing predictions to a predation risk model developed from elk kill sites and applied it to describing spatial patterns in predation risk that were consistent with changes in the distribution of elk over the past decade. We found a strong correlation between risk predicted by kill sites and risk predicted by our approach (r = 0.98, P < 0.001). There was a spatial pattern to predation risk, where elk that migrated east of their winter range were exposed to highest risk from cougars, non-migratory elk were exposed to high risk from wolves and bears, and risk to elk that migrated west of their winter range into protected areas was high only from bears. The patterns in predator risk were consistent with changes in the migratory tactics in this population. The scat-based approach we present permits broad-scale inferences on predation risk for prey.

A Mosaics provide productive ecosystems that include foraging opportunities, breeding grounds, and protection for birds, particularly within mosaics of grassland, wetland, and savanna habitats. This study explored the status of species diversity, richness, and seasonal population rate of avian species within the mosaics of the Padampur grassland of Chitwan National Park (CNP), Nepal. Point count surveys were performed in 10 randomly selected plots by walking transects or riding on elephant back during the rainy season. A total of 118 bird species and 4905 individual birds belonging to 43 families was recorded. Surveys and regression analysis revealed species preferred diverse ecotone habitats interspersed with mosaics of tallgrass prairie, shrubby grassland, savanna and marshy grassland. Regression models also revealed occupancy rates were relatively consistent across seasons, however, months within the rainy and the summer season were lower than autumn and winter. Rarefaction curves showed sampling efforts of approximately 10 months to produce accurate estimates of species richness. Although the diversity indices resulted in insignificant differences between the plots, the CNP appears to provide preferred grassland habitat to bird species all year round. This study suggests conservation efforts to consider these survey methods and estimates when implementing initiatives. This paper recommends concerned authorities to prioritize and give continuity to bird conservation, including grassland management alongside the wetlands within the CNP.

1. Quantifying consumption and prey choice for marine predator species is key to understanding their interaction with prey species, fisheries, and the ecosystem as a whole. However, parameterising a functional response for large predators can be challenging because of the difficulty in obtaining the required datasets on predator diet and the availability of multiple prey species. 2. This study modelled a Multi-Species Functional Response (MSFR) to describe the relationship between consumption by harbour porpoises (Phocoena phocoena) and the availability of multiple prey species in the southern North Sea. Bayesian methodology was employed to estimate MSFR parameters and to incorporate uncertainties in diet and prey availability estimates. Prey consumption was estimated from stomach contents data of stranded harbour porpoises. Prey availability to harbour porpoises was estimated based on the spatial overlap between prey distributions, estimated from fish survey data, and porpoise foraging range in the days prior to stranding predicted from telemetry data. 3. Results indicated a strong preference for sandeel in the study area. Prey switching behaviour (change in preference dependent on prey abundance) was confirmed by the favoured Type III functional response model. Variation in the size of the foraging range (estimated area where harbour porpoises could have foraged prior to stranding) did not alter the overall pattern of the results or conclusions. 4. Integrating datasets on prey consumption from strandings, predator foraging distribution using telemetry and prey availability from fish surveys into the modelling approach provides a methodological framework that may be appropriate for fitting MSFRs for other predators.

Understanding and preserving intra-specific diversity (ISD) is important for species conservation. However, ISD units do not have taxonomic standards and are not universally recognized. The terminology used to describe ISD is varied and often used ambiguously. We compared classical and authoritative definitions of terms used to describe ISD with terms used in recent studies of three fish taxa: sticklebacks (Gasterosteidae), Pacific salmon and trout (Oncorhynchus spp., “PST”), and lampreys (Petromyzontiformes). Our review revealed the terminological ambiguity of “races” and “subspecies”, found similar definitions of “subspecies” and “ecotype”, and of “ecotype” and “reaction norms”. “Species pairs” describes two phenotypes; however, in some situations more than one phenotype may occur. “Ecotype” was originally used to describe patterns in genes and ecology, and recent studies employing this term tend to report a genetic basis in ISD. Ecotype is used most frequently in genetic- and evolution-based journals. By contrast, “life history” includes biological parameters that affect population growth and decline, and this term tends to be used in organismal- and ecology-based journals. When the genetic or demographic components of ISD are not well understood, a conservative approach would be to refer to expressions of this diversity as “phenotypes”. The nature of human interests in particular taxa could influence how these organisms are studied, and hence the ways in which their ISD is understood, described, and conserved.

1. The use of a drone to count the flock sizes of 33 species of waterbirds during the breeding and non-breeding periods was investigated. 2. In 96% of 343 cases, drone counting was successful. 18.8% of non-breeding birds and 3.6% of breeding birds exhibited adverse reactions: in the former, the birds were flushed, whereas the latter attempted to attack the drone. 3. The automatic counting birds was best done with the microbiology software - ImageJ / Fiji: the average bird counting rate was 100 birds in 82 seconds. 4. Machine learning using neural network algorithms proved to be an effective and fast way of counting birds – 100 birds in 23 seconds. However, as the preparation of images and machine learning time are time-consuming, this method is recommended only for large data sets and large bird assemblages. 5. The responsible study of wildlife using a drone should only be carried out by persons experienced in the biology and behaviour of the animals concerned.

Fat metabolism in toothed whales is different from other mammals. RT-qPCR is still a reliable technique for studying the relative expressions of various genes involved in metabolism. This study was done for Risso’s dolphin, a toothed whale and information produced here will be important for further transcriptomics studies focused on unrevealed marine mammal fat metabolism. In this study, we sought to identify a suitable reference gene with minimum resources. Seven candidate reference genes ZC3H10, FTL, LGALS1, RPL27A, GAPDH, FTH1 and DCN were initially tested for amplification efficiency using RT-qPCR by producing standard curves. Then, three nearly 100% efficient genes FTL, LGALS1 and GAPDH were selected for the gene stability analysis to determine one stable gene across eight different fat tissues, liver, and muscle of Risso’s dolphins based on four algorithms, provided in geNorm, NormFinder, BestKeeper and Delta Ct. Finally, a RefFinder comprehensive ranking was done based on stability values and the genes were ranked as: FTL>LGALS1>GAPDH. The FTL and LGHLS were identified as the most stable genes; however, GAPDH was third, a well-known housekeeping gene for mammals. Finally, we suggest using FTL as a reliable reference gene for functional genomics studies on toothed whales in the future.

Nest building can represent an energetically-costly activity for a variety of animal taxa. Besides, the determinants of within-species variation in the design of nests, notably with respect to natural and sexual selection, are still poorly known although the situation has been partly remedied recently. Based on an observational study, we examined the influence of nesting conditions (nesting-substrate quality, colony, laying date, and year) on the volume of male-built nests and its potential role as a post-mating sexually-selected display in the whiskered tern Chlidonias hybrida, a monogamous species with obligate bi-parental care breeding on unstable aquatic vegetation beds. No relationship was found between the nest volume and the nesting-substrate quality (i.e. nest stability) indicating that the density of white waterlily leaves was large enough when whiskered terns breed. In contrast, building a large nest likely constitutes a selective advantage since nests were larger in less densely populated colonies and for early breeders whatever the year. Since being influenced by nesting conditions, the volume of male-built nests was unlikely to be a sexually selected trait in whiskered terns. The reproductive effort by females (the probability of laying one, two or three eggs, and variation in mean egg volume per clutch) was indeed not correlated with the volume of male-built nests. The fitness consequences of building a large nest are yet to be studied and additional investigations are recommended to better depict the participation of males early during breeding (including notably courtship feeding) and later to chick provisioning.

Recent research into starling species has revealed the existence of vocal social markers and a link between song temporal structuring and social organisation. The aim of the present study was to develop a genetic tool for understanding the population structuring and behaviour (social/parental transmission) and mating in Pale-winged Starlings (Onychognathus nabouroup), a songbird which is found in arid areas of southern Africa. Using next-generation sequencing, microsatellite markers comprising six dinucleotides, eighteen trinucleotides and twenty-four tetra-nucleotides specific to the Pale-winged Starling were isolated and developed. A total of 77 birds were sampled from the Augrabies Falls Nature Reserve in South Africa (n=53) and the Ai Ais-Richtersveld Transfrontier Park resort in Namibia (n=24), respectively. Fifteen polymorphic microsatellite markers were genotyped. The statistical programme STRUCTURE revealed four different genetic clusters within the two populations. There is low genetic divergence (mean Fst value of 0.01) between the two populations, which is supported by the mean number of effective migrants (22.45) between the populations. ML-Relate data analysis indicated that all individuals sampled from both populations have relatives within and across the two populations with three exceptions in the Augrabies Falls Nature Reserve region. Birds from either population migrate and join the other population maintaining gene flow between the two populations. Each population has a high degree of genetic diversity present between individuals. There is little inbreeding and high allelic richness in both sampled populations, which will allow them to adapt to future environmental changes. The developed microsatellites have inferred information for the success of this species. Social structure, relatedness and behaviour were inferred and regardless of genetic relationships these birds maintain a stable social environment and harbour strong social bonds between same and opposite sex group members as well as mates.

In 2010, vulnerable golden bandicoots (Isoodon auratus) were translocated from Barrow Island, Western Australia, to a predator-free enclosure on the Matuwa Indigenous Protected Area. Golden bandicoots were once widespread throughout a variety of arid and semi-arid habitats of central and northern Australia. Like many small to medium-sized marsupials, the species has severely declined since colonisation and has been reduced to only four remnant natural populations. Between 2010 and 2020 the reintroduced population of golden bandicoots on Matuwa was monitored via capture-mark-recapture data collection which was used in spatially explicit capture-recapture analysis to monitor their abundance over time. In 2014, we used VHF transmitters to examine the home range and habitat selection of 20 golden bandicoots in the enclosure over a six-week period. We used compositional analysis to compare the use of four habitat types. Golden bandicoot abundance in the enclosure slowly increased between 2010 and 2014 and has since plateaued at approximately one quarter of the density observed in the founding population on Barrow Island. The population may have plateaued because some bandicoots escape through the fence. Golden bandicoots used habitats dominated by scattered shrubland over spinifex grass more than expected given the habitat’s availability. Nocturnal foraging range was influenced by sex and trapping location, whereas diurnal refuge habitat was consistent across sex and trapping location. Our work suggests that diurnal refuge habitat may be an important factor for the success of proposed translocations of golden bandicoots.

1. The use of machine learning technologies to process large quantities of remotely-collected audio data is a powerful emerging research tool in ecology and conservation. 2. We applied these methods to a field study of tinamou (Tinamidae) biology in Madre de Dios, Peru, a region expected to have high levels of interspecies competition and niche partitioning as a result of high tinamou alpha diversity. We used autonomous recording units to gather environmental audio over a period of several months at lowland rainforest sites in the Los Amigos Conservation Concession and developed a Convolutional Neural Network-based data processing pipeline to detect tinamou vocalizations in the dataset. 3. The classified acoustic event data are comparable to similar metrics derived from an ongoing camera trapping survey at the same site, and it should be possible to combine the two datasets for future explorations of the target species’ niche space parameters. 4. Here we provide an overview of the methodology used in the data collection and processing pipeline, offer general suggestions for processing large amounts of environmental audio data, and demonstrate how data collected in this manner can be used to answer questions about bird biology.