The use of museum specimens held in natural history repositories for population and conservation genetic research is increasing in tandem with the use of next generation sequencing technologies. Short Tandem Repeats (STRs), or microsatellite loci, are commonly used genetic markers in population and conservation genetic studies. However, they traditionally suffered from a host of issues: fragment size homology, high costs, and low throughput as a result of capillary electrophoresis genotyping and difficulty in reproducibility across laboratories. Next generation sequencing technologies can address these problems, but the incorporation of DNA derived from museum specimens suffers from significant fragmentation and contamination with exogenous DNA. Combatting these issues requires extra measures of stringency in the lab and during data analysis, yet there have not been any studies evaluating microsatellite allelic dropout from museum specimen extracted DNA. In this study, we explore a high throughput sequencing method to evaluate the amount of variation found within museum specimen DNA extracts for previously characterized microsatellites across PCR replicates. We found it useful to classify samples based on quality after replicated PCRs, which determined the rate by which genotypes were accurately recovered. We also found that longer microsatellites performed worse in all museum specimens, so when designing a study invoking museum specimens, short markers (under 250 bp) should be preferentially selected. Allelic dropout rates across loci were dependent on sample quality. The high quality museum specimens performed as well, and recovered nearly as high quality metrics as our tissue sample. Mitochondrial DNA sequences were not predictive of nuclear DNA presence, as all samples recovered cytochrome b fragments yet many lacked microsatellite genotypes, particularly in samples deemed low quality. Based on our results, we have provided a set of best practices for screening, quality assurance, and incorporation of reliable genotypes from museum specimens.

To test the hypothesis whether a lower metabolic rate is expected in cave organisms compared to surface ones due to an adaptation to food scarcity in subterranean environments, we measured the oxygen consumption rates of individuals from hypogean (i.e. subterranean) and epigean (i.e. surface) populations of the troglophilic newt Calotriton asper. We found that epigean individuals exhibit higher rates than hypogean ones and showed that when we acclimated epigean C. asper to cave conditions, these individuals reduced their oxygen consumption. We compared the metabolic levels of hypogean and epigean C. asper acclimated and non-acclimated to the cave, with the obligate cave salamander Proteus anguinus as wells as two epigean species: an urodel (Ambystoma mexicanum) and a fish (Gobio occitaniae). As predicted, we find differences between hypogean and epigean species, and that the troglophilic C. asper exhibited in-between performances. We argue then that this shift of the metabolic level observed between epigean C. asper non-acclimated and acclimated to the cave is not directly due to the food availability in our experiments but to a stasis of the temperature. However we then discuss that this adjustment of the metabolic level under a temperature close to the thermal optimum may secondarly allow individuals to cope with the food limitations of the subterranean environement.

1. Quantitative PCR (qPCR) has been commonly used to measure gene expression in a number of research contexts, but the measured RNA concentrations do not always represent the concentrations of active proteins which they encode. This can be due to transcriptional regulation or post-translational modifications, or localisation of immune environments, as can occur during infection. However, in studies using free-living non-model species, such as in ecoimmunological research, qPCR may be the only available option to measure a parameter of interest, and so understanding the quantitative link between gene expression and associated effector protein levels is vital. 2. Here we use qPCR to measure concentrations of RNA from mesenteric lymph node (MLN) and spleen tissue, and multiplex ELISA of blood serum to measure circulating cytokine concentrations in a wild population of a model species, Mus musculus domesticus. 3. Few significant correlations were found between gene expression levels and circulating cytokines of the same immune genes or proteins, or related functional groups. Where significant correlations were observed, these were most frequently within the measured tissue (i.e. the expression levels of genes measured from spleen tissue were more likely to correlate with each other rather than with genes measured from MLN tissue, or with cytokine concentrations measured from blood). 4. Potential reasons for discrepancies between measures, including differences in decay rates and transcriptional regulation networks are discussed. We highlight the relative usefulness of different measures under different research questions, and consider what might be inferred from immune assays.

A research study on morphometrics of Kalophrynus palmatissimus (known as Lowland Grainy Frog) at Ayer Hitam Forest Reserve (AHFR), Selangor and Pasoh Forest Reserve (PFR), Negeri Sembilan was carried out from 12 November 2016 to 13 September 2017. The study was conducted to examine data on the morphometric traits of K. palmatissimus at the two forest reserves. 15 morphometric traits of K. palmatissimus were taken by using vernier calipers. Frog surveys were done by using 15 and 18 nocturnal 400 m transect lines at AHFR and PFR, respectively. In addition, five climatic data were recorded. The results showed that most of the morphometric traits in AHFR (n = 34) and PFR (n = 31) were positively correlated within each other. General Linear Model (GLM) analysis, showed that snout-vent length (SVL) influenced most morphometric traits, except for hand length. Later, it was found that the snout-vent length of K. palmatissimus in AHFR were slightly larger than PFR. From PCA analysis, morphometric traits were grouped into two components for AHFR and PFR, respectively. In AHFR, head length, eye diameter, head width, internarial distance, interorbital distance, forearm length, tibia length, foot length, and thigh length were strongly correlated while snout length and eye-nostril distance were strongly correlated. In PFR, eye diameter, head width, internarial distance, interorbital distance, foot length and thigh length were strongly correlated, while snout length and eye-nostril distance were strongly correlated; hence, suggesting that all morphometric traits grow simultaneously in K. palmatissimus with eye-nostril distance (EN), and snout length (SL) were closely growing simultaneously at AHFR and PFR. To conclude, the data collections showed the 15 different morphometric traits of K. palmatisssimus between AHFR and PFR with K. palmatissimus at AHFR were slightly larger than at PFR. Key words: Kalophrynus palmatissimus, forest reserve, morphometrics, climatic factors, transect lines

Geographical gradients in species diversity have long fascinated biogeographers and ecologists. However, the extent and generality of the positive/negative effects of the important factors governing functional diversity (FD) patterns are still debated, especially for the freshwater domain. We examined lake productivity and functional richness (FRic) of waterbirds sampled from 35 lakes and reservoirs in northern China with a geographic coverage of over 5 million km2. We used structural equation modelling (SEM) to explore the causal relationships between geographic position, climate, lake productivity and waterbirds FRic. We found unambiguous altitudinal and longitudinal gradients in lake productivity and waterbirds FD, which were strongly mediated by local environmental factors. Specifically, we found 1) lake productivity increased northeast but decreased with altitude, and the observed gradients were driven by climate and nutrient availability, with 93% of variation explained in the individual SEM; 2) waterbirds FD showed similar geographic and elevational gradients.; the environmental factors which had direct and/or indirect effects on these geographic and elevational gradients included climate, lake productivity and morphology, which collectively explained more than 56% of the variation in waterbirds FD; and 3) a significant (P = 0.029) causality between lake productivity and waterbirds FD was confirmed. Nevertheless, the causality link was relatively weak in comparison with climate and lake area (standardized path coefficient was 0.65, 0.21, and 0.17 for climate, area, and productivity, respectively). Through articulating the dominant causality paths, our results could contribute to the mechanistic explanations underlying the observed broad–scale biodiversity gradients.

Accurately estimating abundance is a critical component of monitoring and recovery of rare and elusive species. Spatial capture-recapture (SCR) models are an increasingly popular method for robust estimation of ecological parameters. We provide a maximum likelihood analytical framework to assess results from empirical studies to inform SCR sampling design, using both simulated and empirical data from non-invasive genetic sampling of seven boreal caribou populations (Rangifer tarandus caribou) which varied in range size and estimated population density. We use simulated population data with varying levels of clustered distributions to quantify the impact of non-independence of detections on density estimates, and empirical datasets to explore the influence of varied sampling intensity on the relative bias and precision of density estimates. Simulations revealed that clustered distributions of detections did not significantly impact relative bias or precision of density estimates. The empirical genotyping success rate was 95.1%. Empirical results indicated that reduced sampling intensity had a greater impact on density estimates in smaller ranges. The number of captures and spatial recaptures were strongly correlated with precision, but not relative bias. The best sampling designs did not differ with estimated population density but differed between large and small ranges. We provide an efficient framework implemented in R to estimate the detection parameters required when designing SCR studies. The framework can be used when designing a monitoring program to minimize effort and cost while maximizing effectiveness, which is critical for informing wildlife management and conservation.

Diversity gradients are observed in various groups of organisms. For fishes in streams, the Water-Energy, Productivity and Temporal Heterogeneity hypotheses are considered the best combination to explain richness patterns. The relationship between species diversity and the variables that represent the hypotheses are generally considered linear and stationary, that is, there is equal relation of cause and effect along an entire geographical extension. The assumption of stationarity has not been tested or even observed in diversity gradients, thus producing imprecise models. Therefore, our goal is to quantify stationarity in the existing relationships between the ichthyofauna of streams and the Water-Energy, Productivity and Temporal Heterogeneity hypotheses using a Geographically Weighted Regression – GWR. In the proposed model, there is conspicuous absence of stationarity between fish species richness and the tested hypotheses. Furthermore, water-energy dynamics were observed as a possible metabolic restriction mechanism acting on the community structuring of stream fishes. This mechanism divides the fish fauna from the studied Brazilian watercourses in two regions: i) Amazonian, characterized by a stable climate and populations with little resistance to thermal variation; and ii) Central, featured by greater ranges of temperature and fish populations resistant to thermal variation.

Participatory approaches such as community photography can engage the public in questions of societal and scientific interest. We combined data extracted from community-sourced, spatially-explicit photographs with research findings from 2018 fieldwork in the Yukon, Canada, to evaluate winter coat moult patterns and phenology in mountain goats (Oreamnos americanus), a cold-adapted, alpine mammal. Leveraging the community science portals iNaturalist and CitSci, in less than a year we amassed a database of several hundred unique photographs spanning some 4500 kms between latitudes 37.6°N and 61.1°N from 0m to 4333m elevation. Using statistical methods accounting for incomplete data, a common issue in community science datasets, we evaluated effects of intrinsic (sex and presence of offspring) and environmental (latitude and elevation) factors on moult onset and rate and compared our findings with published data. Shedding occurred over a 3-month period, May 29-September 6. Effects of sex and offspring on the timing of moult were consistent between the community-sourced and our Yukon data and with findings on wild mountain goats at a long-term research site in west-central Alberta, Canada. Males moulted first followed by females without offspring (6.4 days later in the coarse-grained, geographically-wide community science sample; 23.7 days later in our fine-grained Yukon sample) and lastly females with new kids (5.5; 17.9, respectively). Shedding was later at higher than at lower elevations. Northern latitudes had slightly later but shorter shedding periods. We detected a possible shift in moult timing in recent years (2015-2018) that warrants additional investigation. Despite data limitations, such as bias towards recent photographs, our findings establish a basis for employing community photography to examine broad-scale questions about the timing of ecological events, as well as sex differences in response to possible climate drivers. As such, community photography can inspire public participation in environmental and outdoor activities with reference to iconic wildlife.

1. Data on reproductive features of temperate terrestrial isopods species is well-known, for some species this knowledge is still incipient. Armadillidium tunisiense is a newly discovered and endemic Tunisian with an only recent study concerning its breeding patterns. 2. Seen the interspecific and intraspecific variations due to local variations in environmental conditions. We decided to describe the main characteristics of A. tunisiense’s life cycle from the Chambi mountain, the highest point in Tunisia, by determining the population structure; the reproduction dynamics, the sex ratio and fertility. 3. The breeding patterns and the reproductive cycle of A. tunisiense were studied on 2908 individuals collected on regular bias from July 2009 to July 2011 from the Chambi mountain. Our specimens were divided into six categories. Where females were followed from the day of collection until their death. An in-depth study of a well-defined number (35 specimens) of reproductive females were desiccated to define the fertility by counting the eggs contained in the marsupium. 4. We found that A. tunisiense from the Chambi mountain is a semelparous species with a seasonal reproductive pattern, characterized by a reproduction period followed by a sexual rest. Also, we could’ve confirmed the positive relationship between the sizes of ovigerous females and fertility. With 5 eggs recuperated in a 5.2 mm female while 33 eggs were encountered in an 8 mm female. As well as for the sex ratio which characterized by fluctuation (0.49-1.12), but mainly in favor of females over that of males. 5. The combined results of the previous study and ours maintain on the role of environmental conditions that interfere to explain the interspecific variations were observed for the launch and the duration of the reproduction period. Thus, altitude might confirm the intraspecific variations between both studied populations of A. tunisiense.

Riparian habitats have high insect abundance and consequently provide good foraging opportunities for insectivorous bats. Here we investigate how insect abundance, temperature, season, and elevation affect the foraging behaviour of Daubenton’s (Myotis daubentonii) and common pipistrelle (Pipistrellus pipistrellus) bats along the river Wharfe in north Yorkshire. Insect abundance correlated positively with ambient air temperature. Abundance reached a maximum around sunset before dropping to low levels with frequent zero captures throughout the middle of the night. There was often a second smaller peak in insect abundance around sunrise. Insects at all elevation habitats were mainly dipterans, and most (92%) of these were nematocerans. There was a mismatch between peak insect abundance and bat detections, with highest insect detection just before bats arrived in the evening or after they left in the morning. Insect abundance and bat Feeding Buzz Ratios (FBR) did not differ significantly between treeless and tree-lined habitats. Significantly more M. daubentonii detections were recorded in August than in May, but there was no significant difference in the number of mean feeding buzzes between months. More P. pipistrellus FBRs were recorded at lower elevations; however, there was no elevational difference in FBR for M. daubentonii, although more FBRs were recorded for this species. Detections of M. daubentonii were fairly constant throughout the night, while P. pipistrellus exhibited large variations in number of passes per hour. P. pipistrellus arrived c.a. half an hour earlier at tree-lined habitats than tree-less habitats, likely taking advantage of protective tree cover to gain additional foraging time when insects are more abundant. M. daubentonii, on the other hand, generally arrived later. There was no correlation between FBR and number of aerial insects for either species. Bat detections (and therefore presence) is influenced by factors other than the availability of aerial prey.

Scientists are increasingly using volunteer efforts of citizen scientists to classify images captured by motion-activated trail-cameras. The rising popularity of citizen science reflects its potential to engage the public in conservation science and accelerate processing of the large volume of images generated by trail-cameras. While image classification accuracy by citizen scientists can vary across species, the influence of other factors on accuracy are poorly understood. Inaccuracy diminishes the value of citizen science derived data and prompts the need for specific best practice protocols to decrease error. We compare the accuracy between three programs that use crowdsourced citizen scientists to process images online: Snapshot Serengeti, Wildwatch Kenya, and AmazonCam Tambopata. We hypothesized that habitat type and camera settings would influence accuracy. To evaluate these factors, each photo was circulated to multiple volunteers. All volunteer classifications were aggregated to a single best answer for each photo using a plurality algorithm. Subsequently, a subset of these images underwent expert review and were compared to the citizen scientist results. Classification errors were categorized by the nature of the error (e.g. false species or false empty), and reason for the false classification (e.g. misidentification). Our results show that Snapshot Serengeti had the highest accuracy (97.9%), followed by AmazonCam Tambopata (93.5%), then Wildwatch Kenya (83.4%). Error type was influenced by habitat, with false empty images more prevalent in open-grassy habitat (27%) compared to woodlands (10%). For medium to large animal surveys across all habitat types, our results suggest that to significantly improve accuracy in crowdsourced projects, researchers should use a trail-camera set up protocol with a burst of three consecutive photos, a short field of view, and consider appropriate camera sensitivity. Accuracy level comparisons such as this study can improve reliability of future citizen science projects, and subsequently encourage the increased use of such data.

The host-associated microbiome plays a significant role in health. However, the roles of factors such as host genetics and microbial interactions in determining microbiome diversity remain unclear. We examined these factors using amplicon-based sequencing of 175 Thoropa taophora frog skin swabs collected from a naturally fragmented landscape in southeastern Brazil. Specifically, we examined (1) the effects of geography and host genetics on microbiome diversity and structure; (2) the structure of microbial eukaryotic and bacterial co-occurrence networks; and (3) co-occurrence between microeukaryotes with bacterial OTUs known to affect growth of the fungal frog pathogen Batrachochytrium dendrobatidis (including anti-Bd bacteria commonly referred to as “antifungal”). Microbiome structure correlated with geographic distance, and microbiome diversity varied with both overall host genetic diversity and diversity at the frog MHC IIB immunity locus. Our network analysis showed the highest connectivity when both eukaryotes and bacteria were included, implying that ecological interactions occur among Domains. Lastly, anti-Bd bacteria did not demonstrate broad negative co-occurrence with fungal OTUs in the microbiome, indicating that these bacteria are unlikely to be broadly antifungal. Our findings emphasize the importance of considering both Domains in microbiome research, and suggest that probiotic strategies for amphibian disease management should be considered with caution.

This paper documents a mass en route mortality event of adult summer chum salmon (Oncorhynchus keta) returning to the Koyukuk River, Alaska in the Yukon River watershed. In response to reports from local communities, researchers (including the author) surveyed ca. 315 km of river on July 26 and 27, 2019 and counted 1,364 dead individuals, but this likely reflects a small fraction of the true number of fish that died. We sampled 73 carcasses to confirm death occurred prematurely prior to complete maturation and spawning, to quantify sex and length. Visual inspection revealed a substantial fraction exhibited patterns of fungal growth consistent with secondary infections of skin lesions caused by the ubiquitous natural bacterial pathogen Flavobacterium columnare. Water temperatures during the survey averaged 17.1°C and the water was approximately 85% saturated with oxygen (ca. 8.5 mg/L), which likely contributed to the stress for upstream migrants. Evidence suggests size-selective en route mortality as female migrants that died were 2% and male migrants 5% shorter than individuals that survived to their spawning grounds on Henshaw Creek. This translates to very strong estimates of natural selection using standardized selection differentials, though randomization tests of size data revealed this observed outcome of selection was expected to occur 25% of the time due to chance alone. It is unclear whether selection acts on body size directly or indirectly through correlated phenotypic traits such as run timing. The mortality event likely underpins the below average returns of summer chum salmon to the Koyukuk in 2019, suggesting an impact on spawner abundance. The future consequences of this, or potentially increasingly frequent, en route mortality events for population productivity and the extent to which genetic adaptation or adaptive phenotypic plasticity of migration behavior may facilitate persistence of these populations is unknown.

Grey Crowned Crane Balearica regulorum is described as an icon of Africa’s wetlands and grasslands and is listed as Endangered on the IUCN Red List of Threatened species. Efforts towards its conservation actions are nonetheless hindered by among others, lack of knowledge on factors influencing breeding productivity such as nest-site selection. Factors influencing the probability of nest-site selection were investigated at Lake Ol’ Bolossat, a 43.3 km2 wetland located in the central Kenya highlands as a breeding resident. The number and distribution pattern of breeding pairs was also determined. A total of 123 breeding pairs were recorded, 103 in the lake and 20 in the surveyed satellite wetlands thus providing the largest database of breeding Grey Crowned Cranes reported in Kenya to date. Mean breeding pair density for the lake’s marshes was 6.50±0.84 (SE) pairs/km2 with a mean distance between nests of 302.53±17.02 (SE) m. Generalized Linear Models were used to select the most important environmental variables explaining nest-sites selection. The model selection algorithm yielded a subset of 8 best models, where the most important predictor variables (i.e. those with ΔAICc <2) were determined as water depth (preferred above 50 cm), vegetation height (above 60-90 cm) and distance from the water edge (ca.100 m). Water depth and vegetation height had positive effects on nesting probability while the distance to water edge exhibits quadratic tendency. These findings provide key insight into Grey Crowned Crane nesting ecology and a basis for breeding habitat modification and management. This study underscores the importance of Lake Ol’ Bolossat as a critical breeding site and its significant role in the species’ population recovery and survival. The lake should consequently be re-gazetted as a National Park to ensure effective and sustainable control of anthropogenic activities in and around the lake in favour of Grey Crowned Crane.

In district Haripur, KPk, Pakistan Treepie Dendrocitta vagabunda parvula (Latham, 1790) (Passeriformes: Corvidae), is a widespread resident bird commonly found. Feeding and Food habits of Treepie were studied by direct focal observation method analysis of gut content and faecal matter. Treepie prefers tree and cultivation areas insects for foraging activities, feeding on animal and plant is an omnivore items ranging from vertebrate species to invertebrate. Feeding upon like red palm weevil, grasshopper, cockroaches, banana stem weevil, nestlings of squirrel and house rat, it feeds up on many pests of agricultural crops Treepie is an important biocontrol agent in the agro ecosystem of the region

We evaluated the richness, diversity and composition of medium and large mammalian community in the Loka Abaya National Park (LANP), southern Ethiopia, and how these parametrs differ among four habitat types: wooded grassland, riverine forest, hilly scrubland and wetland) and between seasons.We recorded total of 2,573 individual animals of 28 medium and large mammal species in the park. This included three globally threatened species: the endangered African wild-dog (Lycaon pictus) and the ‘vulnerable’ Leopard (Penthra pardus) and Hippopotamus (Hippopothamus amphibus). Season had little effect on species richness, diversity and composition both across and within habitat types. However, species richness across season was significantly different among the four habitat types, in declining order of: wooded grassland > riverine forest > hilly scrubland > wetland. The strongest similarity in species composition, both across and within seasons, was found between wooded grassland and riverine forest. In terms of relative abundance, mammalia assemblage of the wooded grassland and wetland habitats had more evenly distributed number of species with different relative abundance categories. Overall, Papio anubis, Chlorocebus aethiops and Tragelephus strepsiceros were the three most abundant species across habitat types. In conclusion, findings of our study reveal that LANP plays an important role in Ethiopia’s mammal conservation. Our findings will serve as a base-line information for managers of the park to make effective conservation decisions and as a baseline for researchers wishing to conduct related ecological studies.

Fish migrations are energetically costly, especially when moving between fresh and saltwater, but are a viable strategy for Pacific salmon and trout (Oncorhynchus spp.) due to the advantageous resources available at various life stages. Anadromous steelhead (O. mykiss) migrate vast distances and exhibit variation for migration phenotypes that have a genetic basis at candidate genes known as greb1L and rock1. We examined the distribution of genetic variation at 13 candidate markers spanning greb1L, intergenic, and rock1 regions versus 246 neutral markers for 113 populations (n = 9,471) of steelhead from inland and coastal lineages in the Columbia River. Patterns of population structure with neutral markers reflected genetic similarity by geographic region as demonstrated in previous studies, but candidate markers clustered populations by predominate genetic variation associated with migration timing. Mature alleles for late migration had the highest frequency overall in steelhead populations throughout the Columbia River, with only 9 of 113 populations that had a higher frequency of premature alleles for early migration. While a single haplotype block was evident for the coastal lineage, we identified multiple haplotype blocks for the inland lineage. The inland lineage had one haplotype block that corresponded to candidate markers within the greb1L gene and immediately upstream in the intergenic region, and the second block only contained candidate markers from the intergenic region. Haplotype frequencies had similar patterns of geographic distribution as single markers, but there were distinct differences in frequency between the two haplotype blocks for the inland lineage. Redundancy analyses were used to model environmental effects on allelic frequencies of candidate markers and significant variables were migration distance, temperature, isothermality, and annual precipitation. This study improves our understanding of the spatial distribution of genetic variation underlying migration timing in steelhead as well as associated environmental factors and has direct conservation and management implications.

Recent studies have demonstrated the great advantages of marine reserves in solving bycatch problems by maintaining the persistence of endangered species without sacrificing the fisheries yields of target species. However, transient phenomena rather than equilibrium states of population dynamics still require further research. Here, with a simple and general model, the transient dynamics of strong stock fish species are investigated under the condition of weak stock persistence. A surprising and counter-intuitive finding is that fisheries yields can strongly fluctuate even if population density both inside and outside marine reserve only slightly varies, leading to transient inconsistency between the population densities and fisheries yields. This finding suggests that population density dynamics cannot be used to predict the transient phenomena of fisheries yields (or vice versa) in fisheries management. These results will deepen our understanding of the transient phenomenon in marine ecology.

Phenotypic divergence in response to divergent natural selection between environments is a common phenomenon in species of freshwater fishes. Intraspecific differentiation is often pronounced between individual inhabiting lakes versus stream habitats. The different hydrodynamic regimes in the contrasting habitats may promote a variation of body shape, but this could be intertwined with morphological adaptions to a specific foraging mode. Herein, I studied the divergence pattern of the European minnow (Phoxinus phoxinus), a common freshwater fish that has paid little attention despite its large distribution. In many Scandinavian mountain lakes, they are considered as being invasive and were found to pose threats to the native fish populations due to dietary overlap. Minnows were recently found to show phenotypic adaptions in lake versus stream habitats, but the question remained if this divergence pattern is related to trophic niche partitioning. I therefore studied the patterns of minnow divergence in morphology (i.e. using geometric morphometrics) and trophic niches (i.e. using stomach content analyses) in the lake Ånnsjön and its tributaries to link the changes in body morphology to the feeding on specific resources. Lake minnows showed a strong reliance on zooplankton and a more streamlined body shape with an upward facing snout, whereas stream minnows fed on macroinvertebrates (larvae and adults) to a higher degree and had a deeper body with a snout that was pointed down. Correlations showed a significant positive relationship of the proportion of zooplankton in the gut and morphological features present in the lake minnows. The results of this study highlight the habitat-specific divergence pattern in morphology and resource use in this ubiquitous freshwater fish, which may promote contrasting inter-specific interactions in the respective food webs.

Extensive range loss for the Golden-winged Warbler (Vermivora chrysoptera) has occurred in areas of intrusion by the Blue-winged Warbler (V. cyanoptera) potentially related to their close genetic relationship. We compiled data on social pairing from nine studies for 2,679 resident Vermivora to assess evolutionary divergence. Hybridization between pure phenotypes occurred with 1.2% of resident males for sympatric populations. Pairing success rates for Golden-winged Warblers was 83% and for Blue-winged Warblers was 77%. Pairing success for the hybrid Brewster’s Warbler was significantly lower from both species at 54%, showing sexual selection against hybrids. Backcross frequencies for Golden-winged Warblers at 4.9% was significantly higher than for Blue-winged Warblers at 1.7%. More frequent backcrossing by Golden-winged Warblers, which produces hybrid phenotypes, may contribute to the replacement of Golden-winged by Blue-winged Warblers. Reproductive isolation due to behavioral isolation plus sexual selection against hybrids was 0.966. Our analyses suggest that plumage differences are the main driving force for this strong isolation with reduced hybrid fitness contributing to a lesser degree. The major impact of plumage differences to reproductive isolation is compatible with genomic analyses (Toews et al. 2016), which showed the largest genetic difference between these phenotypes occurred with plumage genes. These phenotypes have maintained morphological, behavioral, and ecological differences during two centuries of hybridization. Our estimate of reproductive isolation supports recognition of these phenotypes as two species. The decline and extirpation of the Golden-winged Warbler in almost all areas of recent sympatry suggest that continued coexistence of both species will require eco-geographic isolation.

Evolutionary theory predicts that a host infected with a parasite that reduces its future survival and/or fecundity should be selected towards an increased investment in current reproduction. In this study we use the cestode Ligula intestinalis and its intermediate fish host Engraulicypris sardella in Wissman Bay, Lake Nyasa (Tanzania) as a model system. Using data about infestation of E. sardella fish hosts by L. intestinalis collected for a period of 10 years, we explored (i) whether parasite infection affects the fecundity of the fish host E. sardella and (ii) whether host reproductive investment has increased at the expense of growth at maturity. We found that L. intestinalis had a strong negative effect on the fecundity of its intermediate fish host. For the non-infected fish we observed an increase in relative gonadal weight over the study period, while somatic growth at maturity decreased during the study period. Our findings suggest that the cestode L. intestinalis might have selected for increased investment in current reproduction in its fish host E. sardella in Lake Nyasa. This calls for further studies to assess whether these changes reflect plastic or evolutionary responses. We also discuss the synergy between parasite and fishery-mediated selections as a possible explanation for the decline of E. sardella stock in the lake. KEYWORDS Engraulicypris sardella; Ligula intestinalis; life history evolution; selective agents; parasitism; fishing.

The peninsular effect is a geographical phenomenon that explains patterns of species richness. Hypotheses regarding the peninsular effect in bird taxa should be more focused on testing not only recent deterministic processes but also migrant inflow associated with recent environmental variations. We aimed to identify the latitudinal patterns of passerine species richness and test hypotheses regarding recent deterministic processes (climate, primary productivity, habitat diversity, forest area, and anthropogenic disturbances) and migration influence (ratio of migrant species richness) in the Korean peninsula. We used the distribution data of 147 passerine species from 2006 to 2012. Single regression between passerine species richness and latitude supported the existence of the peninsular effect. Mean temperature induced by latitude gradient negatively affected LAI and forest area, and positively habitat diversity. However, passerine species richness was only influenced by LAI and forest area. Ratio of migrant species richness increased as decreasing habitat diversity and was not influenced by LAI and forest area. And we found that ratio of migrant species richness increased with increasing latitude, and contributed to the increasing in passerine species richness. No. of patches did not influenced passerine species richness. These results support the existence of the peninsular effect in the distribution of passerine birds induced by recent deterministic processes such as primary productivity and habitat area, and migrant species inflow caused by competition.

Scavenging can have important consequences for food web dynamics, for example, it may support additional consumer species and affect predation on live prey. Still, few food web models include scavenging. We develop a dynamic model that includes predators, scavengers, live prey, and a carrion pool to show ramifications of scavenging for predation in simple food webs. We explicitly model carrion biomass and scavenging behavior and investigate the effect of scavenging for predation under different assumptions. Our modeling suggests that the presence of scavengers can both increase and decrease predator kill rates and overall predation in model food webs and the impact varies (in magnitude and direction) with context. In particular, we explore the impact of the amount of dynamics allowed in the predator, scavenger, and prey populations as well as the direction and magnitude of interference competition between predators and scavengers. We provide a road map to the different outcomes and link these theoretical outcomes to evidence from different empirical studies.

Birds have been observed to have dietary preferences for unsaturated fatty acids (FAs) during migration. Polyunsaturated fatty acids (PUFAs) increase the exercise performance of migrant birds; however, PUFAs are also peroxidation prone and might therefore incur increased costs in terms of enhanced oxidative stress in migratory individuals. To shed light on this potential constraint, we analysed plasma FA composition and estimated the susceptibility to peroxidation of migrants and residents of the partially migratory common blackbird (Turdus merula) at a stop-over site during autumn migration. As predicted, migrant birds had higher relative and absolute levels of PUFAs compared to resident birds. This included the strictly dietary ω-3 PUFA α-linoleic acid, suggesting a dietary preference for these fatty acids in migrants. Interestingly, the FA unsaturation index, which is an index of lipid peroxidation susceptibility, did not differ between migrants and residents. These findings suggest a mechanism where birds alter their levels of metabolic substrate to increase exercise performance without simultaneously increasing the risk of lipid peroxidation and oxidative stress. In summary, our results are in line with the hypothesis of increased exercise performance being constrained by oxidative stress during migration, which is manifested in changes in the composition of key FAs to retain the unsaturation index constant despite the increased levels of peroxidizable PUFAs.