Lynx body size in Norway is related to its main prey (Roe deer) density, climate, and latitude

Using questionnaire surveys and occupancy modelling to identify conservation priorities for the Critically Endangered Balkan lynx Lynx lynx balcanicus

With an estimated < 50 adult individuals remaining, the Critically Endangered Balkan lynx Lynx lynx balcanicus is one of the rarest, most threatened and least-studied large carnivores. To identify priority conservation areas and actions for the subspecies, during 2006–2014 we conducted 1,374 questionnaire surveys throughout the potential range of the Balkan lynx to (1) evaluate human–lynx interactions and identify potential threats, and (2) determine the probability of site use in 207 grid cells through occupancy modelling. Human–lynx interactions were related mainly to poaching of lynx, and damage to livestock by lynx. Poaching was intense throughout the potential range of the subspecies, apparently having affected 50–100% of the total estimated extant population. Damage to livestock was recorded only in relation to sheep, mainly in the southern part of the lynx's potential range. Occupancy modelling indicated 108 grid cells with high probability of site use, which was affected mainly by increased terrain ruggedness and reduced forest cover. Based on the combined results of our study we identified five priority areas for conservation, as well as in situ habitat protection, community participation in the conservation of the subspecies, and the improvement and implementation of the existing legal framework as the priority conservation actions for the Balkan lynx.

Long-range gene flow and the effects of climatic and ecological factors on genetic structuring in a large, solitary carnivore: the Eurasian lynx

Due to their high mobility, large terrestrial predators are potentially capable of maintaining high connectivity, and therefore low genetic differentiation among populations. However, previous molecular studies have provided contradictory findings in relation to this. To elucidate patterns of genetic structure in large carnivores, we studied the genetic variability of the Eurasian lynx, Lynx lynx throughout north-eastern Europe using microsatellite, mitochondrial DNA control region and Y chromosome-linked markers. Using SAMOVA we found analogous patterns of genetic structure based on both mtDNA and microsatellites, which coincided with a relatively little evidence for male-biased dispersal. No polymorphism for the cytochrome b and ATP6 mtDNA genes and Y chromosome-linked markers were found. Lynx inhabiting a large area encompassing Finland, the Baltic countries and western Russia formed a single genetic unit, while some marginal populations were clearly divergent from others. The existence of a migration corridor was suggested to correspond with distribution of continuous forest cover. The lowest variability (in both markers) was found in lynx from Norway and Białowieża Primeval Forest (BPF), which coincided with a recent demographic bottleneck (Norway) or high habitat fragmentation (BPF). The Carpathian population, being monomorphic for the control region, showed relatively high microsatellite diversity, suggesting the effect of a past bottleneck (e.g. during Last Glacial Maximum) on its present genetic composition. Genetic structuring for the mtDNA control region was best explained by latitude and snow cover depth. Microsatellite structuring correlated with the lynx's main prey, especially the proportion of red deer (Cervus elaphus) in its diet. Eurasian lynx are capable of maintaining panmictic populations across eastern Europe unless they are severely limited by habitat continuity or a reduction in numbers. Different correlations of mtDNA and microsatellite population divergence patterns with climatic and ecological factors may suggest separate selective pressures acting on males and females in this solitary carnivore.

Evolution in the sabre-tooth cat, Smilodon fatalis, in response to Pleistocene climate change

The late Pleistocene was a time of environmental change, culminating in an extinction event. Few fossil localities record a temporal series of carnivore fossil populations from this interesting interval as well as Rancho La Brea (RLB). We analysed mandibles of Smilodon fatalis from RLB using 2-D geometric morphometrics to examine whether, and how, mandibular shape changes through time. Smilodon fatalis shows mandibular evolution with oscillations between a small, ancestral-type morph in pits 77 (≈37 Kybp) and 2051 (≈26 Kybp), a larger, more derived morph in pits 91 (≈28 Kybp) and 61-67 (≈13.6 Kybp), and an intermediate morph from pit 13 (≈17.7 Kybp). These oscillations end in pit 61-67, with greatest body size, and are estimated to have its widest gape and lowest bite force. Additionally, variation is lowest in pit 61-67, which was deposited concurrent with the Bølling–Allerød warming event, which may have important implications for the timing or conditions during the extinction event. Contra to a temporal Bergmann's rule, such rapid warming events appear to be correlated with larger, derived, morphologies whereas static, cooler, climates correlate with gracile, ancestral morphologies.