Limiting similarity theory predicts that competing species must segregate along one or more dimensions of their ecological niche in order to coexist. In predator communities, interspecific ...interactions are influenced by a diversity of factors; therefore, the behavioural patterns of composing species will differ due to locally adapted interactions. We deployed 32-41 camera-traps in five study areas across the Iberian Peninsula to investigate the temporal relations between mesocarnivores in SW Europe. The selection for a period of the diel cycle and plasticity in activity patterns was evaluated using the Jacobs Selection Index (JSI) and the coefficient of activity overlap (∆₁). Furthermore, we investigated whether temporal shifts can facilitate coexistence by reducing activity overlap. Seven species of mesocarnivores were detected and were assigned into one of three behaviourally distinct groups: diurnal (JSIday≥0.8), strictly nocturnal (JSInight≥0.8) or facultative nocturnal species (0.4≥JSInight>0.8). Most species exhibited substantial flexibility, which allowed them to locally adapt their foraging strategies (intraspecific ∆₁=0.70-0.77). Mean ∆₁ from all interspecific pairwise comparisons was negatively correlated with the number of carnivore species with ≥ 10 detections (r -0.76, p= 0.02). Our results suggest that temporal segregation is likely to play an important role in facilitating mesocarnivore coexistence, especially with increasing community complexity, where most species' activity peaks were asynchronous. These results contribute to understanding the dynamics and behavioural strategies of coexisting mesocarnivores, crucial for forecasting the possible outcomes of conservation or management actions.
Snowshoe hares (
) maintain seasonal camouflage by molting to a white winter coat, but some hares remain brown during the winter in regions with low snow cover. We show that cis-regulatory variation ...controlling seasonal expression of the
gene underlies this adaptive winter camouflage polymorphism. Genetic variation at
clustered by winter coat color across multiple hare and jackrabbit species, revealing a history of recurrent interspecific gene flow. Brown winter coats in snowshoe hares likely originated from an introgressed black-tailed jackrabbit allele that has swept to high frequency in mild winter environments. These discoveries show that introgression of genetic variants that underlie key ecological traits can seed past and ongoing adaptation to rapidly changing environments.
The activity patterns exhibited by animals are shaped by evolution, but additionally fine‐tuned by flexible responses to the environment. Predation risk and resource availability are environmental ...cues which influence the behavioural decisions that make both predators and prey engage in activity bursts, and depending on their local importance, can be strong enough to override the endogenous regulation of an animals’ circadian clock. In Southern Europe, wherever the European rabbit (Oryctolagus cuniculus) is abundant, it is the main prey of most mammalian mesopredators, and rodents are generally the alternative prey. We evaluated the bidirectional relation between the diel activity strategies of these mammalian mesopredators and prey coexisting in south‐western Europe. Results revealed that even though predation risk enforced by mammalian mesocarnivores during night‐time was approximately twice and five times higher than during twilight and daytime, respectively, murids consistently displayed unimodal nocturnal behaviour. Conversely, the European rabbits exhibited a bimodal pattern that peaked around sunrise and sunset. Despite the existence of some overlap between the diel rhythms of mesocarnivores and rabbits, their patterns were not synchronized. We suggest that the environmental stressors in our study areas are not severe enough to override the endogenous regulation of the circadian cycle in murids. European rabbits, however, are able to suppress their biological tendency for nocturnality by selecting a predominantly crepuscular pattern. In spite of the higher energetic input, mesocarnivores do not completely track rabbits’ activity pattern. They rather track rodents’ activity. We propose that these systems have probably evolved towards a situation where some degree of activity during high‐risk periods benefits the overall prey population survival, while the accessibility to sufficient prey prevents predators to completely track them.
Lagomorphs Smith, Andrew T; Johnston, Charlotte H; Alves, Paulo C
2018, 2018-01-01
eBook
Numbering 92 species worldwide, the order Lagomorpha is a focal point of conservation efforts. Approximately one-quarter of all lagomorphs are under conservation concern, and a few are quite ...literally on the brink of extinction. Here, leading conservation biologist Andrew T. Smith and his colleagues bring together the world’s lagomorph experts in the most comprehensive reference on the order ever produced. With detailed species accounts—illustrated with stunning color photos and up-to-date range maps—contributors highlight key ecological roles that lagomorphs play and explain in depth how scientists around the globe are working to save vulnerable populations. Thematic introductory chapters cover a broad spectrum of information about pikas, rabbits, and hares, from evolution, systematics, and diseases to lagomorph conservation status and management. Each animal account begins with the complete scientific and common names for each species. A description of the appearance and unique morphological characteristics is accompanied by a range of standard measurements of adult specimens. Subsequent sections discuss known paleontological data concerning the species, the current state of its taxonomy and geographic variation, and various aspects of the animal’s biology. Aimed at naturalists, professional biologists, and students, this book will also serve as a valuable reference for those conducting biodiversity surveys and conservation throughout the world.
The application of species distribution models (SDMs) in ecology and conservation biology is increasing and assuming an important role, mainly because they can be used to hindcast past and predict ...current and future species distributions. However, the accuracy of SDMs depends on the quality of the data and on appropriate theoretical frameworks. In this study, comprehensive data on the current distribution of the Iberian hare (Lepus granatensis) were used to i) determine the species' ecogeographical constraints, ii) hindcast a climatic model for the last glacial maximum (LGM), relating it to inferences derived from molecular studies, and iii) calibrate a model to assess the species future distribution trends (up to 2080). Our results showed that the climatic factor (in its pure effect and when it is combined with the land-cover factor) is the most important descriptor of the current distribution of the Iberian hare. In addition, the model's output was a reliable index of the local probability of species occurrence, which is a valuable tool to guide species management decisions and conservation planning. Climatic potential obtained for the LGM was combined with molecular data and the results suggest that several glacial refugia may have existed for the species within the major Iberian refugium. Finally, a high probability of occurrence of the Iberian hare in the current species range and a northward expansion were predicted for future. Given its current environmental envelope and evolutionary history, we discuss the macroecology of the Iberian hare and its sensitivity to climate change.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Genetic non-invasive sampling (gNIS) may provide valuable information for population monitoring, as it allows inferences of population density and key behavioural traits such as dispersal, kinship ...and reproduction. Despite its enormous potential, gNIS has rarely been applied to small mammals, for which live-trapping is still the most commonly used sampling method. Here we evaluated the applicability and cost-effectiveness of gNIS compared with live-trapping, to monitor a metapopulation of an Iberian endemic and elusive rodent: the Cabrera vole (
Microtus cabrerae
). We compared the genetic diversity, kinship and dispersal movements inferred using both methods. For that, we optimised microsatellite markers for individual identification of
M. cabrerae
, using both tissue (
n
= 31) and faecal samples (
n
= 323) collected from a metapopulation in south-western Iberia. An initial set of 20 loci was optimised for tissue samples, from which 11 were selected to amplify in faecal samples. Overall, gNIS revealed a higher number of identified individuals (65) than live-trapping (31), and the estimated genetic diversity was similar using data from tissues and gNIS. Kinship analysis showed a higher number of inferred relationships and dispersal events when including gNIS, and indicated absence of sex-biased dispersal. The total cost (fieldwork and genetic analysis) of each genotype obtained through live-trapping was three times greater than for gNIS. Our data strongly supports the high potential and cost-effectiveness of gNIS for monitoring populations of elusive and/or threatened small mammals. We also illustrate how this genetic tool can be logistically feasible in conservation.
The European rabbit (Oryctolagus cuniculus) is an endangered species native to the Iberian Peninsula, playing a vital ecological role in Mediterranean ecosystems as prey for several threatened ...predators. Conservation efforts have been implemented to halt its decline, with a particular focus on the Iberian rabbit subspecies (Oryctolagus cuniculus algirus). Many conservation programmes involve restocking and habitat management, including the construction of artificial warrens to provide essential refuge sites. In this study, we examined the use of four types of artificial warrens (logs, Mayoral®, pallets and tubes) by a restocked Iberian rabbit population within a fenced park in southern Portugal. We investigated the factors influencing warren use, basing our analysis on faecal pellet counts at the entrances of artificial warrens. We analysed spatial and temporal patterns in warren use using a generalised additive mixed model. Additionally, we determined the efficiency of each type of artificial warren by computing the ratio between the costs of building the warren and the level of warren use by the rabbits. Our results indicate that Mayoral, tube and log warrens are significantly less used compared to pallet warrens (Logs: β=–0.171±0.041; Mayoral: β=–0.149±0.058; Tube: β=–0.240±0.071). Moreover, pallet warrens were found to be more cost-effective compared to other types analysed. Furthermore, rabbits preferred artificial warrens surrounded by a higher proportion of shrubs (β=0.132±0.037). Artificial warren use exhibited seasonal variation, declining gradually during the winter and early spring, and recovering in late spring, coinciding with the expected breeding peak. Based on our findings, we recommend the implementation of pallet warrens in rabbit restocking programmes to provide immediate shelter and breeding sites for the released rabbits. Furthermore, artificial warrens should be strategically located near shrub patches to facilitate safe access to vital resources such as food and water.
Lagoviruses belong to the Caliciviridae family. They were first recognized as highly pathogenic viruses of the European rabbit (Oryctolagus cuniculus) and European brown hare (Lepus europaeus) that ...emerged in the 1970-1980s, namely, rabbit haemorrhagic disease virus (RHDV) and European brown hare syndrome virus (EBHSV), according to the host species from which they had been first detected. However, the diversity of lagoviruses has recently expanded to include new related viruses with varying pathogenicity, geographic distribution and host ranges. Together with the frequent recombination observed amongst circulating viruses, there is a clear need to establish precise guidelines for classifying and naming lagovirus strains. Therefore, here we propose a new nomenclature based on phylogenetic relationships. In this new nomenclature, a single species of lagovirus would be recognized and called Lagovirus europaeus. The species would be divided into two genogroups that correspond to RHDV- and EBHSV-related viruses, respectively. Genogroups could be subdivided into genotypes, which could themselves be subdivided into phylogenetically well-supported variants. Based on available sequences, pairwise distance cutoffs have been defined, but with the accumulation of new sequences these cutoffs may need to be revised. We propose that an international working group could coordinate the nomenclature of lagoviruses and any proposals for revision.
ABSTRACT
Animals that occupy temperate and polar regions have specialized traits that help them survive in harsh, highly seasonal environments. One particularly important adaptation is seasonal coat ...colour (SCC) moulting. Over 20 species of birds and mammals distributed across the northern hemisphere undergo complete, biannual colour change from brown in the summer to completely white in the winter. But as climate change decreases duration of snow cover, seasonally winter white species (including the snowshoe hare Lepus americanus, Arctic fox Vulpes lagopus and willow ptarmigan Lagopus lagopus) become highly contrasted against dark snowless backgrounds. The negative consequences of camouflage mismatch and adaptive potential is of high interest for conservation. Here we provide the first comprehensive review across birds and mammals of the adaptive value and mechanisms underpinning SCC moulting. We found that across species, the main function of SCC moults is seasonal camouflage against snow, and photoperiod is the main driver of the moult phenology. Next, although many underlying mechanisms remain unclear, mammalian species share similarities in some aspects of hair growth, neuroendocrine control, and the effects of intrinsic and extrinsic factors on moult phenology. The underlying basis of SCC moults in birds is less understood and differs from mammals in several aspects. Lastly, our synthesis suggests that due to limited plasticity in SCC moulting, evolutionary adaptation will be necessary to mediate future camouflage mismatch and a detailed understanding of the SCC moulting will be needed to manage populations effectively under climate change.
The importance of targeting ecological and evolutionary processes in reserve design has been widely acknowledged in the literature but rarely implemented on islands. Using Socotran reptiles as ...models, we aim to relate richness of widespread and restricted-range species directly with landscape variables and to compare the impact of setting conservation targets for lineages versus species. Socotra Island is a UNESCO Natural World Heritage Site, containing high levels of endemism in relation to its area, especially of reptiles, the vertebrates with the most comprehensive available genetic data. We predicted the occurrences of reptile species using distribution models and used a novel approach to interpolate maps of spatial phylogenetic patterns. Patterns of intra and interspecifc diversity and differences between spatial outputs of lineage and species richness were related to eco-geographic variables. We evaluated differences in target achievement for each conservation unit within protected areas (PAs) under the current Zoning Plan (ZP) using gap and reserve design analyses. Although intraspecific richness was strongly correlated with interspecific richness, differences in their spatial distribution reached ~30% in some areas. Differences were more pronounced for wide-ranging than restricted-range taxa. Gap analysis indicates that most conservation units are under-represented in sanctuaries and that intra and interspecific richness were significantly higher outside PAs. This work will guide local-scale conservation planning as the ZP is due to be re-evaluated. This is one of the few studies on islands using genetic data from an entire class of vertebrates to incorporate lineage diversity in reserve design. This study provides an alternative methodological framework for supporting the use of landscape and genetic tools in reserve design, circumventing the use of phylogenetic distances and deterministic spatial interpolation of lineage diversity that can be widely applied to other systems.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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