Robert Jehle

University of Salford · Ecosystems and Environment Research Centre (EERC)

When backcrosses are fertile, interbreeding between endangered taxa can lead to the admixture of gene pools under threat. One such case pertains to the Mesoamerican crocodile Crocodylus moreletii, a species which shows strong signatures of both recent hybridisation and historic intogression with the American crocodile C. acutus across large parts o...

Detection dogs are increasingly used to locate cryptic wildlife species, but their use for amphibians is still rather underexplored. In the present paper we focus on the great crested newt (Triturus cristatus), a European species which is experiencing high conservation concerns across its range, and assess the ability of a trained detection dog to...

Urbanisation leading to habitat change and fragmentation is a recognised global threat to biodiversity. However, it may also offer opportunities for some species. Genetic diversity, one of the three components of biodiversity, is often overlooked in conservation planning and policy. In the present study, we used a panel of seven microsatellite mark...

Estimates of animal abundance provide essential information for population ecological studies. However, the recording of individuals in the field can be challenging, and accurate estimates require analytical techniques which account for imperfect detection. Here, we quantify local abundances and overall population size of Morelet's crocodiles (Croc...

The putatively positive association between host genetic diversity and the ability to defend against pathogens has long attracted the attention of evolutionary biologists. Chytridiomycosis, a disease caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), has emerged in recent decades as a cause of dramatic declines and extinctions across...

Sex-related differences in mortality are widespread in the animal kingdom. Although studies have shown that sex determination systems might drive lifespan evolution, sex chromosome influences on aging rates have not been investigated so far, likely due to an apparent lack of demographic data from clades including both XY (with heterogametic males)...

Deeply diverged yet hybridizing species provide a system to investigate the final stages of the speciation process. We study a hybridizing pair of salamander species — the morphologically and genetically drastically different newts Triturus cristatus and T. marmoratus — with a panel of 32 nuclear and mitochondrial genetic markers. Morphologically i...

Conserving genetic diversity in wild species is vital for preserving adaptations to local environmental conditions. We conducted a habitat creation project for a flagship European Protected Species of amphibian (northern great crested newt Triturus cristatus) at its northwestern range edge in the Scottish Highlands, combining existing knowledge abo...

Processes of island colonisation have long been of interest to biologists. Colonisation events themselves are rarely observed, but the processes involved may be inferred using genetic approaches. We investigated possible means of island colonisation by common toads (Bufo bufo) in western Scotland (the Isle of Skye and five neighbouring small island...

Interactions between hosts and their resident microbial communities are a fundamental component of fitness for both agents. Though recent research has highlighted the importance of interactions between animals and their bacterial communities, comparative evidence for fungi is lacking, especially in natural populations. Using data from 49 species, w...

1. Effective wildlife restoration is a critical requirement of many conservation actions. The outcome of conservation interventions can be optimized through knowledge of species' habitat requirements, but few studies consider the impact of using explicit evidence from dedicated local research to inform the design phase of habitat management. Furthe...

Biogeographic barriers such as rivers have been shown to shape spatial patterns of biodiversity in the Amazon basin, yet relatively little is known about the distribution of genetic variation across continuous rainforest. Here, we characterize the genetic structure of the brilliant-thighed poison frog (Allobates femoralis) across an 880 km long tra...

Interactions between hosts and their resident microbial communities are a fundamental component of fitness for both agents. Though recent research has highlighted the importance of interactions between animals and their bacterial communities, comparative evidence for fungi is lacking, especially in natural populations. Using data from 49 species, w...

The Andes have experienced an unprecedented wave of amphibian declines and extinctions that are linked to a combination of habitat reduction and the spread of the fungal pathogen, Batrachochytrium dendrobatidis (Bd). In the present study, a range of high-altitude habitats in Southern Ecuador were surveyed for the presence of Bd. With a particular f...

Genomic evidence is increasingly underpinning that hybridization between taxa is commonplace, challenging our views on the mechanisms that maintain their boundaries. Here, we focus on seven catadromous eel species (genus Anguilla) and use genome-wide sequence data from more than 450 individuals sampled across the tropical Indo-Pacific, morphologica...

As there is no agreed national list of species of socio-economic and/or cultural value for Scotland, a set of criteria for selecting species has been developed. These include: • Species prioritised for conservation value • Species identified as being culturally important • Species providing important ecosystem services • Game species • Species coll...

Urbanisation has been identified as a major threat to biodiversity worldwide. As well as consuming land, urban expansion perturbs natural processes such as flooding and nutrient cycling, and fragments habitats. Flooding is of particular concern in many countries as extreme weather events appear to be increasing in frequency. In compliance with the...

Although our knowledge on the population biology of the Morelet’s crocodile (Crocodylus moreletii) has been rapidly increasing over the last decades, only rudimentary information is currently available about populations from the Selva Maya, especially in Mexico. In the region of Calakmul (Campeche, Mexico), C. moreletii inhabits semi-temporary and...

Herpetofauna occurring in the Mayan jungle is one of the richest assemblages in the Americas. The Calakmul Biosphere Reserve (UNESCO World Heritage Site of Culture and Nature due to the forest of outstanding biodiversity) in Mexico contains 89 species, including some Yucatan endemics. Due to the lack of rivers and permanent waterbodies, species div...

The effective size of a population (N e) determines the retention of neutral genetic variation in isolated populations, and is therefore a key parameter in conservation genetics. However, while our knowledge on the genetic properties of endangered populations has vastly improved in recent decades, rather little is known about the drivers of variati...

Urbanisation is a major threat to many taxa including amphibians. Expanding cities take away land from biodiversity, perturb ‘natural processes’ such as flooding and nutrient cycling, and fragment habitats. In addition, urban citizens are less likely to experience nature and the health and well-being effects it provides. In compliance with the EU W...

Although our knowledge on the population biology of the Morelet's crocodile (Crocodylus moreletii) has been rapidly increasing over the last decades, only rudimentary information is currently available about populations from the Selva Maya. In the region of Calakmul (Campeche, Mexico), C. moreletii inhabit semi-temporary and therefore highly dynami...

Genomic evidence is increasingly underpinning that hybridization between taxa is commonplace, challenging our views on the mechanisms that maintain their boundaries. Here, we focus on seven catadromous eel species (genus Anguilla), and use genome-wide sequence data from more than 450 individuals sampled across the tropical Indo-Pacific, morphologic...

In human-modified landscapes, little is known about the influence of aquatic habitat types on the demographic structure of residing amphibian populations. In the present paper, we focus on a European flagship urodele species (the great crested newt Triturus cristatus) at the north-western range of its distribution, applying the method of skeletochr...

While urbanisation is a major threat to global biodiversity, it also brings opportunities for some species. Sustainable Drainage Systems (SuDS) have been installed in all Scottish cities to reduce flood and pollution risk and they can also offer new habitats for wildlife. We studied SuDS in Inverness and the Scottish Central Belt to assess their va...

High‐throughput sequencing data have greatly improved our ability to understand the processes that contribute to current biodiversity patterns. The “vanishing refuge” diversification model is speculated for the coastal forests of eastern Africa, whereby some taxa have persisted and diversified between forest refugia, while others have switched to b...

The distribution of biodiversity within the Amazon basin is often structured by sharp environmental boundaries, such as large rivers. The Amazon region is also characterized by subtle environmental clines, but how they might affect the distributions and abundance of organisms has so far received less attention. Here, we test whether soil and forest...

Supporting Information. Table S1. Locality and coordinates for each modules within the Purus–Madeira interfluvium. Table S2. Sum of A. femoralis and soil and forest-structure properties in 90 plots located along the Purus-Madeira interfluve, in central-southern Amazonia. Fig. S1. Diagram of the RAPELD model research modules, showing all distances:...

Little is known about the phylogeographic history of amphibian populations along the western Fennoscandinavian coast. In the present study, we focus on the common toad (Bufo bufo) and document the spatial distribution of mitochondrial DNA (cytb) haplotypes at 20 localities along its coastal Norwegian range. Two common haplotypes (out of eight haplo...

Understanding the population structure of tropical anguillids residing in the Pacific is vital for their conservation management. Here, the population genetic structure of five sympatric freshwater eels (Anguilla marmorata Quoy & Gaimard, A. megastoma Kaup, A. obscura Steindachner, A. reinhardtii Günther and A. australis Richardson) across 11 weste...

Although our knowledge on the population biology of the Morelet’s crocodile (Crocodylus moreletii) has been rapidly increasing over the last decades, only rudimentary information is currently available about populations from the Selva Maya. The existing outputs of this ongoing project represent the first layer of knowledge for C. moreletii populati...

Amphibians are the most endangered group of vertebrates, and conservation measures increasingly rely on information drawn from genetic markers. The present study explores skin swabs with Whatman FTA® cards as a method to retrieve PCR-amplifiable amphibian DNA. Swabs from ten adult great crested newts (Triturus cristatus) were used to compare FTA® c...

Conservation genetics as a scientific discipline has sometimes been criticised for not offering real-world solutions to conservation problems. We present a study which began as a citizen science project, became a multidisciplinary approach using climate history, habitat specialists, geneticists and conservation agency staff and has ended in a habit...

Sustainable Drainage Systems (SuDS) manage storm-water, reducing flood risk and diffuse pollution, through processes mimicking nature (Woods-Ballard et al. 2015). We postulated that SuDS might bring three benefits to biodiversity (O’Brien 2015): as breeding sites; by connecting otherwise isolated populations to form metapopulations within a habitat...

Population Viability Analysis (PVA) is a commonly used tool to predict the fate of endangered populations. However, although amphibians are the most endangered group of vertebrates, PVAs have so far been underrepresented in their conservation management. In the last decades, the European tree frog (Hyla arborea) has experienced drastic declines mai...

Edge populations are of conservation importance because of their roles as reservoirs of evolutionary potential and in understanding a given species’ ecological needs. Mainly due to loss of aquatic breeding sites, the great crested newt Triturus cristatus is amongst the fastest declining amphibian species in Europe. Focusing on the north-westerly li...

We carried out laboratory experiments to determine whether orientation during migration in the great crested newt (Triturus cristatus) is influenced by acoustic information. Newts retrieved during the aquatic breeding seasons (adults), as well as during the terrestrial phase after breeding (adults and juveniles), were subjected to calls from sympat...

Natural selection is a major force in the evolution of vertebrate brain size, but the role of sexual selection in brain size evolution remains enigmatic. At least two opposing schools of thought predict a relationship between sexual selection and brain size. Sexual selection should facilitate the evolution of larger brains because better cognitive...

Rensch’s rule describes a pattern of allometry whereby sexual size dimorphism (SSD) increases with body size when males are the larger sex, and whereby SSD decreases with body size when females are larger by intraspecific comparison. In groups of related species or sets of conspecific populations, Rensch’s rule has so far largely been confirmed wit...

Anurans are renowned for a high diversity of reproductive modes, but less than 1 % of species exhibit internal fertilisation followed by viviparity. In the live-bearing West African Nimba toad (Nimbaphrynoides occidentalis), females produce yolk-poor eggs and internally nourish their young after fertilisation. Birth of fully developed juveniles tak...

The last decades have shown a surge in studies focusing on the interplay between fragmented habitats, genetic variation, and conservation. In the present study, we consider the case of a temperate pond-breeding anuran (the common toad Bufo bufo) inhabiting a naturally strongly fragmented habitat at the Northern fringe of the species’ range: islands...

Background: Environmental variation associated with season length is likely to promote differentiation in life-history traits, but has been little studied in natural populations of ectotherms. We investigated patterns of variation in egg size, clutch size, age at sexual maturity, maximum age, mean age, growth rate and adult body size in relation t...

The Expensive Brain Framework (EBF) and the Cognitive Buffer Hypothesis are commonly used to explain inter- and intraspecific variation in brain size and brain architecture. Using Andrew’s toad (Bufo andrewsi) as a model species, we investigated whether brain attributes in amphibians are shaped by the interplay between age and the length of the act...

Determining whether isolated populations of a species are native or introduced is important for conservation, as non-native occurrences are likely to be of lower priority for conservation organisations with limited resources. The great crested newt Triturus cristatus is an important wetland flagship species in the UK, and recent evidence suggested...

The spawning areas of tropical anguillid eels in the South Pacific are poorly known, and more information about their life histories is needed to facilitate conservation. We genetically characterized 83 out of 84 eels caught on Gaua Island (Vanuatu) and tagged 8 eels with pop-up satellite transmitters. Based on morphological evidence, 32 eels were...

We characterise nine polymorphic microsatellites for the Critically Endangered lemur leaf frog, Agalychnis lemur. We found between 3 and 8 alleles per locus in 48 captive individuals originating from the last two currently known remaining wild populations of these frogs in Costa Rica. We attribute observed deviations from Hardy–Weinberg and linkage...

Female mate choice promotes the development of male secondary sexual traits such as nuptial colouration, whereas scramble competition favours male traits which enhance their ability for access to females. In the explosively breeding moor frog (Rana arvalis), males express a conspicuous blue colouration during a short reproductive period characteris...

Determining whether isolated populations of a species are native or introduced is important for conservation, as non-native occurrences are likely to be of lower priority for conservation organisations with limited resources. The great crested newt Triturus cristatus is an important wetland flagship species in the UK, and recent evidence suggested...

Background The degree of postcopulatory sexual selection, comprising variable degrees of sperm competition and cryptic female choice, is an important evolutionary force to influence sperm form and function. Here we investigated the effects of mating system and spawning location on the evolution of sperm morphology in 67 species of Chinese anurans....

Few studies have investigated Toxoplasma gondii infections in bat populations and none have reported its presence in protected British bat species. Using a collection of dead/euthanased bats collected from Lancashire, UK, two species of bats (Pipistrellus pipistrellus and Pipistrellus pygmaeus) were tested using a highly sensitive SAG1-PCR method s...

Environmental variation along altitudinal gradients can promote life-history trait differentiation in ectothermic animals. Life-history theory predicts that increased environmental stress results in a shift in reproductive allocation from offspring quantity to quality and a stronger trade-off between egg size and clutch size. To test this predictio...

Aquatic funnel traps are an established technique for the capture of newts. In the United Kingdom they are widely used for commercial surveys of great crested newts (Triturus cristatus) to comply with EU regulations during land developments such as construction activities. The present study demonstrates that widely-used traps constructed from plast...

Amphibians are globally threatened, but not all species are affected equally by different threatening processes. This is true for the threat posed by the chytridiomycete fungus (Batrachochytrium dendrobatidis) . We compiled a European data set for B. dendrobatidis to analyze the trends of infection in European amphibians. The risk of infection was...

Sexual size dimorphism (SSD) is related to ecology, behaviour and life history of organisms. Rensch's rule states that SSD increases with overall body size in species where males are the larger sex, while decreasing with body size when females are larger. To test this rule, we analysed literature as well as own data on male and female body size in...

Species, location, mean size and age within each sex and references of published papers and unpublished data for the 39 anurans species considered in this study. * indicate mean ± SE.

The adaptive significance of sequential polyandry is a challenging question in evolutionary and behavioral biology. Costs and benefits of different mating patterns are shaped by the spatial distribution of individuals and by genetic parameters such as the pairwise relatedness between potential mating partners. Thus, females should become less choos...

We characterise nine polymorphic microsatellites for the caecilian amphibian Boulengerula (cf.) uluguruensis. We found between five and 13 alleles per locus in 17 individuals from six sites across four Eastern Arc Mountain blocks and coastal forest in Tanzania. In the population with the largest sample size (Uluguru North, n = 8), two loci deviated...

EditorialThe “Peer” in “Peer Review”