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493 vertebrate Preprints

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vertebrate behavioral ecology terrestrial description molecular evolution molecular genetics multiple marine comparative method development ecosystem evolutionary ecology natural history ecosystem ecology laboratory theory ecological experiment freshwater community ecology population ecology none of the above genetics statistical sequencing
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Please note: These are preprints and have not been peer reviewed. Data may be preliminary.
Application of genetic structure analysis to explore the cause of variation in radion...
Yui Nemoto
Rie Saito

Yui Nemoto

and 5 more

June 03, 2023
1. After the Fukushima Daiichi Nuclear Power Plant accident in 2011, radionuclides have been detected in the tissues of wild animals. It was found that some individuals had higher radiocesium activity concentrations than others, despite being captured in the same area. One of the reasons for this disparity was attributed to migration from areas where radiocesium contamination level was different. 2. We identified the genetic population of Asian black bears using two genetic markers, such as mtDNA D-loop haplotype and SNPs by MIG-seq analysis. Then, we assessed migration between populations and variation in the radiocesium activity concentrations in the muscle tissue of distinct populations. 3. The SNPs analysis identified clearer two populations (SP1 and SP2) than the mtDNA analysis. Population distribution inferred based on SNPs was affected by geographic features and land use. 4. The radiocesium activity concentrations in muscle tissues in SP2 were higher than those in SP1. The radiocesium activity concentrations in muscle tissue were positively correlated with radiocesium contamination levels at the capture site. Since the radiocesium contamination levels at the capture sites of SP2 were higher than those of SP1, it was inferred that the levels of radiocesium contamination in each population would show a similar pattern. 5. Migration occurred between the genetic populations and migration rate differed between the genetic populations, with the rate of individuals migrating from SP2 to SP1 being smaller than that from SP1 to SP2. Therefore, it was suggested migration was responsible for some individuals having relatively higher radiocesium activity concentrations in muscle tissue, despite being captured in the same area. 6. This study is the first report that showed the genetic structure of Asian black bear in Fukushima Prefecture in fine scale, the migration rate between the populations, and the effect of migration on the variation of radiocesium activity concentration.
Genetic connectivity of little penguin colonies in Australia
Sandra Vardeh
Jennifer Sinclair

Sandra Vardeh

and 5 more

June 02, 2023
The Australian range of little penguins, Eudyptula minor, extends around southern Australia, with range-edge sites near the large cities of Perth (west) and Sydney (east). Both range-edges are closer to the equator than the range-core, being likely to experience similar heating with climate change. As a result, movement to one range-edge is not an option for little penguins, unlike in many other species. Therefore, adaptation at the range edge might be very important for little penguins. Capacity for future adaptation depends upon the variability each site holds, and the amount of exchange between sites. In peripheral sites, incoming dispersal might either forestall demographic collapse and replenish genetic variation (good), or overcome local adaptation and increase disease transmission (bad). We aimed to establish the genetic variability in each site, and the exchange (dispersal) of individuals between sites. Genetic markers included biparentally-inherited microsatellites, and maternally-inherited mitochondrial DNA sequence. For microsatellites, no site appeared to have critically low variation, including the peripheral sites, however there was a significant but slight trend of increased variation from east to west. In contrast, mitochondrial DNA showed a pattern of significantly reduced variation at the two range-edges, possibly indicating differential dispersal patterns in males and females. There appear to be two main genetically distinct groups, in the west and the east, but analysis of lifetime dispersal patterns across the Australian range also suggests complex dispersal, sometimes with high dispersal or similarity between locations that are not adjacent. Our work suggests that despite some differentiation, little penguin sites are interdependent due to complex dispersal patterns, and all have valuable genetic variation. In particular, the peripheral sites are not depauperate of variation, and are moderately connected to the remainder of the distribution, so possibly may be able to adapt in response to climate warming.
Species diversity, abundance and habitat association of small mammals in Wenchi monta...
Kabeta Legese
Afework Bekele

Kabeta Legese

and 1 more

May 27, 2023
Studying small mammals has a paramount significance for ecological, cultural and economic reasons. A survey on the diversity, abundance and habitat association of small mammals in Wenchi highlands, central Ethiopia, was carried out from August 2019 to January 2021. Small mammals were trapped from six different habitats (Hagenia Woodland, Erica Scrub, Qibate, Lakeshore, Erica and Albesa Forests) using Sherman and snap traps in standard trapping grids. A total of 935 rodents belonging to 12 species (Arvicanthis abyssinicus, Desmomys yaldeni, Mastomys natalensis, M. awashensis, Stenocephaylemys albipes, Lophuromys flavopunctatus, L. brevicaudus, L. chrysopus, Dendromus lovati, Lophiomys imhausi, Graphirius murinus, and an unidentified murid rodent), and 24 insectivores belonging to 3 species (Crocidura bailey, C. fumosa and C. olivieri) were recorded. Hystrix cristata and Tachyoryctes splendens were also recorded through indirect evidences. About 52.9% of the identified small mammals were endemic to Ethiopia. A significant variation was observed in the captures of small mammals. The capture rate was higher in live traps (23.85%) than snap traps (8.26%). The diversity and distribution of small mammal species varied among habitats. The highest species diversity (H’=1.74) was recorded in Albesa Forest, while the least was in Qibate Forest (1.43). The highest number of individuals were recorded in Lakeshore Forest (27.73%), whereas the least was in Erica Forest (4.27%). M. natalensis (30.86%) and S. albipes (27.53%) were the two most abundant species, whereas L. imhausi (0.1%) was the least. Wenchi montane forests are one of the most important homes to unique small mammals that need urgent conservation actions.
Molecular phylogeny reveals cryptic diversity in Sibynophis from China (Serpentes: Si...
Peng Guo
Ping Wang

Peng Guo

and 8 more

May 17, 2023
Illumination of species diversity and their distribution is key to evolution, genetics and conservation. The genus of Sibynophis is a group of rare snakes with less attentions. Based on more extensive sampling, we use both mitochondrial fragments and nuclear gene to explore the species diversity of the species of Sibynophis occurring in China. The results showed that S. c. miyiensis is a synonym of S. c. grahami, and S. c. grahami should be gave a specific rank as S. graham. Sibynophis triangularis was uncovered to be new to China and Myanmar. On basis of our specimens and molecular phylogeny results, the species distribution boundaries of each Chinese species were redefined.
Endemic fish calling: acoustics and reproductive behaviour of the Neretva dwarf goby...
Sven Horvatić
Eric Parmentier

Sven Horvatić

and 5 more

May 16, 2023
The Neretva dwarf goby Orsinigobius croaticus (Gobiiformes, Gobionellidae) is an endemic fish native to the freshwaters of the Adriatic Basin in Croatia and Bosnia and Herzegovina. Due to its limited distribution range, specific karst habitat and endangered status, laboratory studies on reproductive biology are scarce. We investigated the sound production and acoustic behaviour of this species during reproductive intersexual laboratory encounters. We performed dissection and micro-computed tomography (μCT) scanning of the pectoral girdle to explore the anatomy of its putative sound producing mechanism. To study interspecific acoustic differences and determine whether acoustic features can discriminate among species, comparative analysis was conducted on sounds produced by closely related soniferous sand gobies. Our results indicate that males of the O. croaticus emit pulsatile sounds composed of a variable number of short (~ 15 ms) consecutive pulses when interacting with females, usually during the pre-spawning phase in the nest, but also during courtship outside the nest. Pulsatile sounds were low-frequency and short pulse trains (~ 140 Hz, < 1000 ms), and spectro-temporal parameters were correlated with physical traits and water temperature. Male visual behaviour rate was higher when co-occurring with sounds and females entered the male’s nest significantly more frequently when sounds were present. Male sound production was accompanied by movements such as head thrust and fin spreading. μCT scans and dissections suggest that O. croaticus shares certain anatomical similarities of the pectoral girdle (osseous elements and arrangement of levator pectoralis muscles) to previously studied sand gobies. Multivariate comparisons, using sounds produced by eight soniferous European sand gobies, effectively distinguished soniferous (and sympatric) species based on acoustic properties. Discrimination success decreased when temperature-dependent features (sound duration and pulse repetition rate) were excluded from analysis. Therefore, we suggest both spectral and temporal features are important for acoustic differentiation of sand gobies.
Constitutive immune function is not associated with fuel stores in spring migrating p...
Shivani Ronanki
Arne   Hegemann

Shivani Ronanki

and 2 more

May 13, 2023
Migratory birds may either upregulate their immune system during migration as they might encounter novel pathogens or downregulate their immune system as a consequence of trade-offs with the resource costs of migration. Support for the latter comes not least from a study that reports a positive correlation in autumn migrating birds between fuel stores and parameters of innate and acquired immune function, i.e., energy exhausted migrants appear to have lowered immune function. However, to our knowledge, no study has tested whether this pattern exists in spring migrating birds, which may face other trade-offs than autumn migrants. Here, we investigate if in spring there is a relationship between fuel stores and microbial killing ability, a measure of innate immune function, and total immunoglobulin (IgY), a measure of acquired immune function, in four migrating bird species: Chaffinches (Fringilla coelebs), Dunnocks (Prunella modularis), Song thrushes (Turdus philomelos) and Northern wheatears (Oenanthe oenanthe). We found no correlation between fuel stores and bacterial killing ability or IgY levels in any of the species. However, there was a significant negative correlation between microbial killing ability and Julian date in Song thrushes and Northern wheatears, and between IgY levels and Julian date in Song thrushes. Sex did not affect immune function in any of the species. Our study suggests that the relationship between immune function and fuel stores may be different during spring migration compared to autumn migration. Differences in the speed of migration or pathogen pressure may result in different outcomes of the trade-off between investment in immune function and in migration among the seasons.
Local bats diversity exceeded the regional bats diversity in Xinjiang, China
Pei-Pei Dong
Wen-Jia Gao

Pei-Pei Dong

and 3 more

May 10, 2023
Echolocation acoustic signature identification is an ideal non-invasive field survey method for chiropteran diversity. Located in the far easternmost region of the Xinjiang Uyghur Autonomous Region where covers one sixth of China’s land territory, Komul city includes a variety of landscapes, including typical mountains, plateaus, plains, and the Gobi Desert, which is home to a number of terrestrial animals. By gathering bat echo sound waves between July and September 2022 and during April 2023, we investigated bat species diversity in Komul, Xinjiang, China. As a result, we identified a total of 24 species of bats belonging to two families and ten genera, of which Myotis is the dominant genus with seven species, followed by Pipistrellus with four species, and both Eptesicus and Nyctalus come after with three species. 16 of these species are novel to Xinjiang. The altitudinal distribution of these species is 500m to 2200m above sea level, and their horizontal distribution includes most of the surveyed region, e.g., Barkol Kazakh Autonomous County, Arturk County, and Ivirghul District. From a conservation perspective, three species (Miniopterus schreibersii、Myotis capaccinii and Nyctalus lasiopterus) and two species (Barbastella barbatellus and Myotis dasycneme) are listed as “vulnerable” and “near threatened” in the IUCN Red List of Threatened Species, respectively. Rest of which are of least concern. Our findings provide a valuable reference for future ecological, genetic, and conservational studies of bats in China, especially in Xinjiang.
Human land-use changes the diets of sympatric native and invasive mammal species
Antje Chiu Werner
Menna Jones

Antje Chiu Werner

and 1 more

May 09, 2023
The consequences of biological invasions and habitat degradation for native biodiversity depend on how species cope with the individual and synergetic challenges these processes present. To assess the impact of anthropogenic land-use on the food web architecture of an invaded community, we examine the diets of nine native and two highly invasive mammal species at different trophic levels, inhabiting different land-uses across six biogeographic regions in Tasmania, Australia. We use two complementary methods, environmental DNA metabarcoding analysis (eDNA) of faeces and stable isotope analysis (SIA) of nitrogen (N) and carbon (C) in whole blood, to account for the high inter-individual and temporal variability in animal diets. eDNA showed regionalisation in the diet of smaller species, with land-use further defining dietary taxa within each region. SIA revealed that bioregion and land-use influence the δ13C values of all carnivore species and omnivores, whereas the δ15N values of these species are influenced only by land-use and not bioregion. Including multiple species showed that native rats are changing their diet in response to the presence of invasive rats, an impact that would have been otherwise attributed to land-use. Our findings demonstrate that human activities and invasive species are molding the diets of invaded communities raising questions about the potential impacts that dietary modifications will have on the life-history traits and the evolutionary consequences these modifications might have on the survival of native species. This highlights the urgency to include human activities in ecological studies and the importance of targeting multispecies assemblages to gain a better understanding of synergetic impacts on native biodiversity.
Genomic signatures of climate adaptation in bank voles
Remco Folkertsma
Nathalie Charbonnel

Remco Folkertsma

and 11 more

May 08, 2023
Evidence for spatially varying selection and adaptive variation can provide insight into a species’ ability to adapt to different environments. However, despite recent advances in genomics, it remains difficult to detect footprints of spatially varying selection in natural populations. Here we analysed ddRAD sequencing data (21,892 SNPs) in conjunction with geographic climate variation to search for signatures of adaptive differentiation in twelve populations of the bank vole (Myodes/Clethrionomys glareolus) distributed across Europe. To identify the loci subject to spatially varying selection and associated with climate variation, we applied multiple genotype-environment association (GEA) methods, two univariate and one multivariate, and controlled for the effect of population structure. In total, we identified 213 candidate adaptive loci, 74 of which were located within genes. In particular, we identified signatures of selection in candidate genes with functions related to lipid metabolism and the immune system. Using the results of redundancy analysis (RDA), we demonstrated that population history and climate have joint effects on the genetic variation in the pan-European metapopulation. Furthermore, by examining only candidate loci, we found that annual mean temperature is an important factor shaping adaptive genetic variation in the bank vole. By combining landscape genomic approaches, our study sheds light on genome-wide adaptive differentiation and the spatial distribution of variants underlying adaptive variation in bank voles that are influenced by local climate.
Opportunities and challenges of citizen science for monitoring a recolonizing large h...
Emu-Felicitas Ostermann-Miyashita
Hendrik Bluhm

Emu-Felicitas Ostermann-Miyashita

and 11 more

May 04, 2023
Monitoring is a prerequisite for evidence-based wildlife management, yet conventional monitoring approaches are often ineffective for species occurring at low densities. However, some species such as large mammals are often observed by lay people and this information can be leveraged through citizen science monitoring schemes. Assessing the quantity, quality, and potential biases of such data sources is crucial before making inferences at scale. For Eurasian moose (Alces alces), a species currently reoccurring in north-eastern Germany in low numbers, we compared three different citizen science tools: a mail/email report system, a smartphone application, and a webpage. Among these monitoring tools, the mail/email report system yielded the greatest number of moose reports in absolute and in standardized (corrected for time effort) terms. The reported moose were predominantly identified as single, adult, male individuals, and reports occurred mostly during late summer. Overlaying citizen science data with independently generated habitat suitability and connectivity maps showed that members of the public detected moose in suitable habitats but not necessarily in movement corridors. Also, moose detections were often recorded near roads, suggestive of spatial bias in sampling effort. Our results suggest that citizen science-based data collection can be facilitated by brief, intuitive digital reporting systems. However, inference from the resulting data can be limited due to unquantified and possibly biased sampling effort. To overcome these challenges, we offer specific recommendations such as engaging outdoor enthusiasts in suitable moose habitats, for improving quantity, quality and analysis of citizen science-based data for making robust inferences about wildlife populations.
Maternal genetic diversity, differentiation and phylogeny of wild yak and four domest...
Donghui Xu
Ruizhe Li

Donghui Xu

and 8 more

May 02, 2023
Yak (Bos grunniens) is a unique livestock animal originating from the Qinghai-Tibet Plateau in China. In the current study, we investigated the maternal genetic diversity, differentiation and phylogeny of wild yak population and four domestic yak breeds (Qinghai-Gaoyuan, Huanhu, Xueduo, and Yushu) in Qinghai, China by analyzing 166 mitochondrial cytochrome b (Cytb) gene sequence variations. Our results indicated that the haplotype and nucleotide diversities of wild yak were 0.883±0.044 and 0.004±0.002, while the total haplotype and nucleotide diversities of four Qinghai domestic yak breeds were 0.646±0.040 and 0.003±0.001, respectively. Among the four Qinghai domestic yak breeds, the haplotype diversity was found to be highest in Yushu yak breed (Hd = 0.770±0.053), while the lowest was recorded in Huanhu yak breed (Hd = 0.501±0.088). Estimates of FST values showed a moderate genetic differentiation between wild yak and Huanhu yak (FST = 0.058) as well as that between Huanhu yak and Yushu yak breeds (FST = 0.052), but a weak genetic differentiation was observed between the other yak breeds/populations (-0.021<FST<0.037). Additionally, the clustering analysis based on RST values showed that Xueduo yak and Huanhu yak were clustered into one group, and each of the other three yak breeds/populations was separated into one group, respectively. Overall, the clustering relationship between wild yak and Yushu yak was closer. Maternal phylogenetic analysis showed that wild yak and four local yak breeds/populations in Qinghai represented in three maternal lineages (Mt-Ⅰ, Mt-Ⅱ, and Mt-Ⅲ), indicating three maternal origins in yak. Our study would provide valuable information for the conservation and utilization of wild yak and Qinghai domestic yak breeds.
Identification of hybrids between the Japanese giant salamander (Andrias japonicus) a...
Kosuke Takaya
Takeshi Ise

Kosuke Takaya

and 2 more

May 02, 2023
Biological invasions are recognized as one of the factors causing biodiversity loss. Incomplete reproductive isolation with a closely related species can result in hybridization when a non-native species is introduced into a new habitat. Management of hybrids is essential for biodiversity conservation; however, the distinction between the two species becomes a challenge in cases of hybrids with similar characteristics to native species. Although image recognition technology can be a powerful tool for identifying hybrids, studies have yet to utilize deep learning approaches. Hence, this study aimed to identify hybrids between native Japanese giant salamanders (Andrias japonicus) and non-native Chinese giant salamanders (Andrias davidianus) using EfficientNet and smartphone images. We used smartphone images of 11 native individuals (with 5 training and 6 test images) and 20 hybrid individuals (with 5 training and 15 test images). In our experimental environment, an AI model constructed with efficientNet-V2 showed 100% accuracy in identifying hybrids. In addition, highlighting the regions that influenced the AI model’s predictions using Grad-CAM revealed that salamander head spots are responsible for correctly classifying native and hybrid species. The results of this study revealed that our approach is one of the methods that enable the identification of hybrids, which was previously considered difficult without identification by the experts. Furthermore, since this study achieved high-performance identification using smartphone images, it is expected to be applied to a wide range of low-cost identification using citizen science.
Effects of landscape structure and patch characteristics on the density of central po...
Ana María Prieto Ramírez

Ana María Prieto Ramírez

April 27, 2023
A better understanding of the impact of habitat loss on population density can be achieved by evaluating effects of both, parameters within remnant habitat patches and parameters of the landscape surrounding those patches. The integration of predictors at the patch and landscape level is scarce in animal ecological studies, especially for reptiles. In this study, a patch-landscape approach was applied to evaluate the combined effects of within patch habitat quality, patch geometry and landscape configuration and composition on the density of remnant populations of the eastern green lizard, Lacerta viridis, in a highly modified landscape in Bulgaria. Landscape composition variables (proportion of different land covers) were measured at different spatial scales surrounding patches. Single scale models were built to evaluate combined effects of all predictors on density, when including all landscape composition variables at a specific spatial scale. Multiscale models were applied to analyze combined effects when including landscape composition variables at the scale of their strongest effect (scale of effect, SoE). Results showed that the SoE of proportion of cropland and urban areas was small (50 m), while for proportion of habitat was large (1.5 Km). The overall effect of habitat loss was better explained by the multiscale model. Population density increased with patch area and decreased with patch shape irregularity and with the proportion of three land cover types surrounding patches -cropland, urban areas and habitat. Combining patch and landscape parameters is important to identify ecological processes that occur simultaneously at different spatial levels and landscape scales, and which would imply the application of multiscale approaches for the protection of wild animal populations. Results are contrasted with what is known about occupancy patterns of the species in the same region, and approaches to integrate both, occupancy and density, in the field design of animal ecological studies are suggested.
Signal detection theory applied to giant pandas: Do pandas go out of their way to mak...
Yue Wang
Ronald Swaisgood

Yue Wang

and 7 more

April 26, 2023
The purpose of inter-animal communication is to allow signals released by the animal to be perceived by others. Scent marking, with its characteristics of specificity and delay, is thought to be the primary mode of communication in giant pandas (Ailuropoda melanoleuca). The “signal detection theory” predicts that animals choose the substrate and location of their scent marks so that the signals released are transmitted more widely and remain longer. As an energetically marginal species, the cost of generating and marking chemical signals is costly for pandas, so they are predicted to make trade-offs in scent marking. However, existing studies do not account for the selective preferences of pandas for marking, as they are only explained by the density of marks at a certain location. Our study wanted to investigate whether the marking behavior of pandas is indeed consistent with signal detection theory. For the first time, we propose to use fecal counts to reflect the intensity of habitat use by pandas, combined with mark counts to determine the selective preference for marking. Our findings show that the scent marking behavior of pandas is consistent with signal detection theory, and that they go out of their way to ensure that their marks are detected. The results of the study will help us to further develop the conservation of pandas and their habitats.
Biological Case Against Downlisting the Whooping Crane and for Improving Implementati...
Andrew Caven
Hillary Thompson

Andrew Caven

and 15 more

April 26, 2023
The Whooping Crane (Grus americana; WHCR) is a large, long-lived bird endemic to North America. The remnant population migrates between Aransas National Wildlife Refuge, USA, and Wood Buffalo National Park, Canada (AWBP), and has recovered from a nadir of 15-16 birds in 1941 to ~540 birds in 2022. Two ongoing reintroduction efforts in Louisiana and the Eastern Flyway together total ~150 birds. Evidence indicates the U.S. Fish and Wildlife Service (USFWS) is strongly considering downlisting the species from an endangered to a threatened status under the Endangered Species Act (ESA). We examined the current status of the WHCR through the lens of ESA threat factors, the USFWS’s Species Status Assessment (SSA) framework, and other avian downlisting actions to determine if the action is biologically warranted. Our research indicates that WHCRs are facing an intensification of most threat drivers across populations and important ranges. The AWBP is still relatively small compared to other crane species and most birds of conservation concern. To date, only one avian species has been downlisted from an endangered status with an estimated population of <3,000 individuals. Representation in terms of WHCRs historic genetic, geographic, and life history variation remains limited. Also, the lack of spatial connectivity among populations, reliance of the reintroduced populations on supplementation, and continued habitat loss suggest that WHCR populations may not be resilient to large stochastic disturbances. Given that reintroduced populations are not self-sustaining, neither supplies true redundancy for the AWBP. Proposed downlisting before recovery plan population criteria have been met is objectively unwarranted and reflects USFWS inconsistency across ESA actions. Only by incorporating basic quantitative criteria and added oversight into ESA listing decisions can we avoid an action as misguided as downlisting the Whooping Crane without consideration of its recovery plan criteria or ostensibly its population ecology.
The genetics-morphology-behaviour trifecta: unravelling the single greatest limitatio...
Joel Gayford

Joel Gayford

April 24, 2023
Sharks, rays and chimaera form the clade Chondrichthyes, an ancient group of morphologically and ecologically diverse vertebrates that has played an important role in our understanding of gnathostome evolution. Increasingly studies have are seeking to investigate evolutionary processes operating within the chondrichthyan crown group, with the broad aim of understanding the driving forces behind the vast phenotypic diversity observed amongst its constituent taxa. Genetic, morphological and behavioural studies have all contributed to our understanding of phenotypic evolution yet are typically considered in isolation in the context of Chondrichthyes. I argue that integrating these core fields of organismal biology is vital if we are to understand the evolutionary processes operating in contemporary chondrichthyan taxa, and how such processes have contributed to past phenotypic evolution. In light of the global extinction crisis facing this clade, this understanding is crucial if we are to successfully conserve rapidly declining chondrichthyan populations.
A long-term study of size variation in Northern Goshawk Accipiter gentilis across Sca...
Samuel Walker
Terje Lislevand

Samuel Walker

and 2 more

April 19, 2023
Changing climate and growing human impacts are resulting in globally rising temperatures and the widespread loss of habitats. How species will adapt to these changes is not well understood. The Northern Goshawk (Accipiter gentilis) can be found across the Holarctic but is coming under more intense pressure in many places. Studies of recent populations in Finland and Denmark have shown a marked decline in body size of Northern Goshawks over the past century. Here we investigate long-term changes to Norwegian populations of Northern Goshawk by including material from the Middle Ages and Viking Age. We measured 240 skeletons of modern Northern Goshawks from Norway, Sweden, Denmark and Finland, and 89 Medieval Goshawk bones. Our results show that Norwegian and Swedish female Goshawks have decreased in size over the past century, whilst males showed little decline. Medieval female Goshawks were larger than contemporary females. The Viking Age specimens showed little difference to modern populations but appeared smaller than specimens from the Medieval period. A decline in forest habitats and a concomitant shift towards smaller prey likely drove a shift to smaller body size in Northern Goshawks. Our study shows that significant body size changes in birds can occur over relatively short time spans in response to environmental factors, and that these effects can sometimes differ between sexes.
Molecular identification and phylogenetic relationship of Bangladeshi pufferfish base...
Md. Sagir Ahmed
Nafisa Islam

Md. Sagir Ahmed

and 5 more

April 15, 2023
Pufferfish is common in marine, brackish and freshwater habitats in Bangladesh. Pufferfish poisoning sporadically occurs due to the consumptions of toxic pufferfish throughout the country. A study was conducted for molecular characterization and phylogenetic analysis of Bangladeshi pufferfish using two markers, mitochondrial cytochrome c oxidase I (COI) and 16S ribosomal RNA (16S rRNA) genes. A total of 34 barcode sequences (19 COI & 15 16S) from 30 collected specimens representing six species and four genera. The mean length of the sequences were 644 bp and 613 bp for COI and 16S, respectively. The average %GC content was 50.06 for COI which was higher compared to the 16S rRNA (46.61). Average Kimura two parameter (K2P) distances within species was found as 0.29 ± 0.01 for COI and 0.70 ± 0.06 for 16S rRNA. The Maximum Likelihood (ML) phylogenetic analysis of COI and 16S rRNA gene sequences revealed that the corresponding species were clustered together in the same clade. Cluster sequence analyses result revealed five Operational Taxonomic Units (OTUs). DNA based identification of the rest puffer species of Bangladesh with multiple sequences and phylogenetic relationship remains to be established.
Otolith radiocarbon signatures provide distinct migration history of walleye pollocks...
Kozue Ando
Yusuke Yokoyama

Kozue Ando

and 7 more

April 13, 2023
1. Otoliths have been widely studied as natural recorders of the entire life cycle of aquatic teleosts. Trace elements and stable isotope rations in otoliths are well understood and used as proxies of migration histories, however few elements have shown the potential to reconstruct the migration history of oceanodromous fish. 2. This study reports the first use of radiocarbon in otolith to reconstruct the horizontal migration history of fish. We analyzed three different stocks of walleye pollock Gadus chalcogrammus around Hokkaido, Japan. 3. Radiocarbon concentration from the outermost edge of otoliths showed a general consistency with seawater radiocarbon concentration of the sampling region, validating the application of otolith radiocarbon concentration to fish migration studies. Pollocks of all three stocks generally inhabited the nearby sampling area throughout their life cycle, though some pollocks of the Okhotsk and Japan Sea stocks respectively showed a possibility of migration between different sea regions. 4. This study confirmed a novel method using radiocarbon concentrations to reconstruct the migration history of marine teleost. Using the high sensitivity of otolith radiocarbon concentration observed in this study, it may be possible to detect fish migration with higher spatial resolution than previous studies using conventional proxies.
Evaluating and optimising performance of multispecies call recognisers for ecoacousti...
Simon Linke
Daniella Teixeira

Simon Linke

and 2 more

April 12, 2023
Monitoring the effect of ecosystem restoration can be difficult and time consuming. Autonomous sensors, such as acoustic recorders, can aid monitoring across long time scales. This project successfully developed, tested and implemented call recognisers for eight species of frog in the Murray-Darling Basin. Recognisers for all but one species performed well and substantially better than many species recognisers reported in the literature. We achieved this through a comprehensive development phase, which carefully considered and refined the representativeness of training data, as well as the construction (amplitude cut-off) and the similarity thresholds (score cut-offs) of each call template used. Recogniser performance was high for almost all species examined. Recognisers for C. signifera, L. fletcherii, L. dumerilii, L. peronii, and C. parinsignifera all performed well, with most templates having ROC values (the proportion of true positive and true negatives) over 0.7, and some much higher. Recognisers for L. peronii, L. fletcherii and L. dumerilii performed particularly well in the training dataset, which allowed for responses to environmental watering events, a restoration activity, to be clearly observed. While slightly more involved than building recognisers using commercial packages, the workflows ensure that a high quality recogniser can be built and the performance fine-tuned using multiple parameters. Using the same framework, recognisers can be improved in future iterations. We believe that multi-species recognisers are a highly effective and precise way to detect the effects of ecosystem restoration.
Individual fitness in a small desert mammal predicted by remotely sensed environmenta...
Avril Harder
Mekala Sundaram

Avril Harder

and 3 more

April 12, 2023
The increasing availability of satellite imagery has supported a rapid expansion in forward-looking studies seeking to track and predict how climate change will influence wild population dynamics. However, these data can also be used in retrospect to provide additional context for historical data in the absence of contemporaneous environmental measurements. We used 167 Landsat-5 Thematic Mapper (TM) images spanning 13 years to identify environmental drivers of fitness and population size in a well-characterized population of banner-tailed kangaroo rats (Dipodomys spectabilis) in the southwestern United States. Overall, we found that our specific ecological predictions regarding relationships between environmental measures calculated from Landsat TM data and population demographic trends were supported by our results. However, for surface temperature, we found evidence of two decoupled processes that may be driving population dynamics in opposing directions over distinct time frames. These relationships would not have been identified in the absence of remotely sensed data, indicating that such information can be used to test existing hypotheses and generate new ecological predictions regarding fitness at multiple spatial scales and degrees of sampling effort. To our knowledge, this study is the first to directly link remotely sensed environmental data to individual fitness measures, opening a new avenue for incorporating remote sensing data into eco-evolutionary studies.
Native reed-specific bird Reed Parrotbill appears in exotic Smooth Cordgrass
Dawei Wu
Pan Chen

Dawei Wu

and 4 more

December 09, 2022
Bird diversity has declined as native birds have avoided using the green desert after the Smooth Cordgrass Spartina alterniflora invaded coastal China. After many years of coexistence, a few passerine birds began to enter and use Smooth Cordgrass, but only birds of nonspecialised habitat. In this study, we first found that a native reed-specific bird, the Parrotbill Calamornis heudei, flocked and sang in a Smooth Cordgrass habitat in the whole overwintering period near Sheyang Port in Yancheng, Jiangsu Province. This phenomenon indicates that native obligate birds may be forced to adapt to exotic Smooth Cordgrass habitats after long-term coexistence; obviously, the distribution, feeding and reproduction of birds would be affected. Is this an ecological trap? Which may lead to unknown ecological consequences. We suggest that more research attention should be given to this process occurring along the Chinese coast.
Complete mitogenomes of pangasiid catfishes and their phylogeny for taxonomic implica...
Yen Duong
THI KHANH LINH PHAM

Yen Duong

and 5 more

April 07, 2023
Although Pangasiidae (four genera: Pangasius, Pangasianodon, Helicophagus, and Pseudolais) is known to be a monophyletic family, the generic and phylogenetic relationships, as well as inter- and intrafamilial relationships of the catfish families in Siluroidei, are poorly resolved. In this study, we obtained complete mitogenomes from three catfish species of the Mekong River in Vietnam: Pangasius mekongensis (16,462 bp), Pangasius krempfi (16,475 bp), and Pangasianodon hypophthalmus (16,523 bp) and reconstructed a comprehensive phylogeny with 117 mitogenomes of 32 recognized siluriform families. The genomic features of the three mitogenomes were similar to those of previously reported pangasiids, including all regulatory elements, extended terminal associated sequences (ETAS), and conserved sequence blocks (CSBs) (CSB-1, CSB-2, CSB-3, and CSBs, A to F) in the control region. The phylogeny established Pangasiidae as monophyletic and a sister group of Austroglanididae. The [Pangasiidae + Austroglanididae] + (Ictaluridae + Cranoglanididae) + Ariidae] clade is a sister group to the “Big Africa” major clade of Siluriformes. Furthermore, both phylogenies constructed from the single barcodes (83 partial cox1 and 80 partial cytB, respectively) clearly resolved the Pangasiidae’s intrafamilial and intergeneric relationships. Pangasianodon was monophyletic and conclusively as a sister to the (Pangasius + Helicophagus + Pseudolais) group. Pangasius. mekongensis was placed as a sister taxon to P. pangasius within the genus Pangasius, while Pangasius sanitwongsei was found to be related to and grouped with Pangasianodon. However, in the single-gene phylogenies, this species was assigned to the [Pangasius + Helicophagus + Pseudolais] group. The datasets in this study are useful for reappraising pangasiid taxonomy, as well as for siluriform catfish identification, DNA barcoding, systematics, phylogenetics, population genetics, and timeline and mode of diversification studies.
Altitude, latitude, and climate zone as determinants of mountain hare (Lepus timidus)...
Allan Stokes
Tim Hofmeester

Allan Stokes

and 5 more

April 06, 2023
Local adaptation to annually changing environments has evolved in numerous species. Seasonal coat colour change is an adaptation that has evolved in multiple mammal and bird species occupying areas that experience seasonal snow cover. It has a critical impact on fitness as predation risk may increase when an individual is mismatched against its habitat’s background colour. In this paper we investigate the impact of landscape covariates on moult timing in a native winter-adapted herbivore, the mountain hare (Lepus timidus), throughout Norway. Data was collected between 2011 and 2019 at 678 camera trap locations deployed across an environmental gradient. Based on this data, we created a Bayesian multinomial logistic regression model that quantified the correlations between landscape covariates and coat colour phenology and analysed among season and year moult timing variation. Our results demonstrate that mountain hare moult timing is strongly correlated with altitude and latitude with hares that live at higher latitudes and altitudes keeping their winter white coats for longer than their conspecifics that inhabit lower latitudes and altitudes. Moult timing was also weakly correlated with climate zone with hares that live in coastal climates keeping their winter white coats for longer than hares that live in continental climates. We found evidence of some among year moult timing variation in spring, but not in autumn. We conclude that mountain hare moult timing has adapted to local environmental conditions throughout Norway.
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