Genetic analysis of sable (<Emphasis Type="Italic">Martes zibellina</Emphasis>) and pine marten (<Emphasis Type="Italic">M. martes</Emphasis>) populations in sympatric part of distribution area in the northern Urals

Analysis of nucleotide sequences of the mitochondrial DNA (mtDNA) control region (495 bp) of sables (Martes zibellina) and pine martens (M. martes) from allopatric parts of the species ranges has shown a considerable interspecific genetic distance (>3%). In sympatric populations of these species in the northern Urals, differences between two species-specific mtDNA lineages are still large; however, classification of each individual nucleotide sequence with one of the two lineages is not correlated with whether the given animal is phenotypically a sable, a pine marten, or a potential hybrid (the so-called “kidas”). This indicates a high degree of reciprocal introgression of the sable and pine marten mtDNA in the northern Urals and suggests that their interspecific hybridization is common in the sympatric zone.     

A PCR-RFLP-based method to distinguish sable (<Emphasis Type="Italic">Martes zibellina</Emphasis>) and pine marten (<Emphasis Type="Italic">Martes martes</Emphasis>)

Species identification is an important issue in conservation and a particular focus for wildlife forensics. Molecular biological methods retain a unique power to differentiate between difficult samples that lack other identifiable characteristics. The pine marten (Martes martes) and sable (Martes zibellina) are closely related species with very similar pelage characteristics and are often difficult to distinguish from each other. The sable, however, in contrast to the pine marten, remains an endangered and protected animal in China with both hunting and fur trade strictly prohibited for this species. Here, we present a polymerase chain reaction-based restriction fragment length polymorphism method for distinguishing the two species. We sequenced a 638-bp fragment of cytochrome b gene in 39 sables, 68 pine martens, and 10 stone martens and identified all variable nucleotides. A new primer pair was subsequently designed to amplify a 316-bp fragment containing restriction sites of enzyme BseG I and BamH I that are different among martens. When the fragment was cut using BseG I, the resulting restriction pattern was identical in the sable and pine marten, but differed from all other martens. When cut using BamH I, the fragment generated two diagnostic fragments in the sable which could distinguish them from pine martens. This method was valid for all haplotypes of sable and pine marten thus far identified and has high potentially applicability for the identification of the two species.     

A comparative analysis of craniological variability of Eurasian (sable and pine marten) and North American (American marten) species of the <Emphasis Type="Italic">Martes</Emphasis> genus

This paper studies the craniological variability of closely related species—the pine marten Martes martes, the American marten M. americana, and the sable M. zibellina. The study included the data on 22 nonmetric characters of skulls in 2344 individuals. The studied Martes species were revealed to have an evident species-specific manifestation of the investigated craniological characters. Sables stand apart most of all in the interspecific comparison of populations. The degree of epigenetic variability is somewhat higher in the sable than in the pine marten. The American marten significantly differs from Eurasian species in the manifestation of the nonmetric skull characters, which is noted when analyzing even a small number of samples.     

Genetic variability of sable Martes zibellina L., pine marten M. martes L., and their hybrids in Western Siberia: Protein and DNA polymorphism

Using four types of markers, the genetic variability of sable and pine marten inhabiting Western Siberia was examined. Izoenzyme and restriction endonuclease analysis of the mtDNA cytochrome b gene fragment, as well as the ISSR-PCR and analysis of microsatellite variation, revealed a low differentiation level of sable and pine marten and confirmed the hybrid origin of atypical representatives of these species. The hybrids were characterized by an increased heterozygosity level and were genetically closer to sable than to pine marten. In atypical martens, the presence of mtDNA haplotypes of eastern sable was identified. This could be the consequence of the reintroduction of the Barguzin sable in the 20th century. In Western Siberia, the introgression of genes between sable and pine marten was massive and symmetrical. It apparently occurred in the past and continues in the present.     

The geographic ranges of Martes species (Carnivora,Mustelidae) in the Middle Urals in the Late Pleistocene and Holocene

Martes mandibles from Late Pleistocene and Holocene sites in the Middle Urals were identified to the species level using discriminant analysis. As has been shown, sable lived there in the Late Pleistocene, with its geographic range covering all this area until the end of the 18th century; however, its range started to reduce towards the north and northeast in the early 19th century. Over 150 years, the southwestern boundary of the sable range shifted by 3° to reach the current position by the mid-20th century. The pine marten appeared in the Middle Urals in the Holocene no later than 8000 years ago and inhabits this territory at present.     

Isoenzyme spectra of lactate dehydrogenase in tissues of mammals of the Mustelidae family

A comparative analysis of distribution of lactate dehydrogenase (LDH) isoenzymes in the heart, kidneys, lungs, spleen, liver and skeletal muscle was performed in 4 species of carnivorous mammals (Mustelidae family): American mink (Mustela vison Schr.), polecat (Mustela putorius L.), sable (Martes zibellina L.) and pine marten (Martes martes L.). It was found that in the mink, unlike pure terrestrial mustelids (polecat, sable, pine marten), the anaerobic LDH-5 fraction was predominant in the LDH isoenzyme spectrum in the liver, skeletal muscle, lungs and spleen. In all species studied, aerobic B(H) subunits of LDH were found to prevail in the heart and kidney, whereas anaerobic A(M) subunits prevailed in the liver and spleen. The tissue- and species-specific features of LDH isoenzyme spectra revealed in different mustelids reflect the biochemical adaptation of the animals to environmental conditions.     

Intraguild dietary overlap and its possible relationship to the coexistence of mesocarnivores in intensive agricultural habitats

The stone marten (Martes foina) and the pine marten (M. martes) are closely related mammalian carnivores potentially subject to exploitative competition. The recent expansion of the pine marten into the intensively cultivated plain of the River Po (NW Italy), where previously only stone marten occurred, offered an interesting opportunity to analyse their relationships. We studied the distribution and diet of Martes species and trophic niche overlap between martens and red foxes (Vulpes vulpes) in two study areas, each with two pseudoreplicates, by analysing genotyped faeces. Our results seem to confirm the displacement of the stone marten from one study area, the pine marten being the only Martes species occurring where previously the stone marten had been reported. We found a large food niche overlap between red fox and both stone and pine martens, but with evidence of size-related differences in the consumption of some food items. We hypothesised that, due to the poor prey-base of the environment, highly altered by intensive crop cultivation, intense interspecific competition originally occurred between the red fox and stone marten. The heightening of interspecific competition caused by the entry of the pine marten in the predator guild may have caused the displacement of the stone marten, at least temporarily. The mechanism of such displacement needs to be clarified through further surveys in areas where the three species occur sympatrically.     

On Certain Properties of Water and Energy Metabolism in Representatives of Martes and Mustela Genera (Mammalia: Mustelidae)

The quantities of consumed food and water, quantity and moisture contents of faeces as well as quantity and concentration of excreted urine were determined in representatives of Martes—European pine marten (M. martes) and sable (M. zibellina)—as well as in polecat (Mustela putorius). Under the same cage conditions and free access to food, all three species have similar energy value of their daily diet. However, the level of drinking water consumption and the ratio between the daily total water and energy intake was reliably higher in both Martes species than in polecat. In addition, both marten and sable featured much higher rate of evaporation loss in the overall water balance and, consequently, a higher quantity of heat dissipated with evaporation as compared to polecat. Comparison of the obtained and previous data (Sokolov et al., 1995; Rozhnov, 1991) allowed us to propose that the mentioned differences are specific for representatives of Martes and Mustela genera irrespective of ecological specialization of particular species.     

Range expansion of the pine marten (Martes martes) in an agricultural landscape matrix (NW Italy)

Habitat segregation is considered to favour the coexistence of sympatric pine martens Martes martes and stone martens M. foina, the latter being displaced to agricultural and urbanised areas. Subsequent to the report of pine martens in cultivated areas of the western River Po plain (NW Italy), we reviewed all available information on the presence of this species in plain areas of northern Italy and, for two study areas, applied a non-invasive PCR-RFLP method for the identification of Martes species from faecal mtDNA.A total of 24 pine marten records were collected, grouped in the western part of the River Po plain. The number of records showed an exponential increase from 1988 to 2007, the percentage of woods in a 10 km² wide circular plot surrounding the location of records being inversely correlated to its distance from the 300 m a.s.l. contour line. In the two study areas, 36 out of 119 “marten-like” faeces were assigned to the pine marten, whilst none belonged to the stone marten. In the best monitored area, the pine marten was present almost constantly.Our results suggest that the pine marten is expanding its range to include cultivated areas which were previously considered a prerogative of the more synanthropic stone marten.     

Non-invasively determined multi-site variation in pine marten <Emphasis Type="Italic">Martes martes</Emphasis> density,a recovering carnivore in Europe

Pine martens (Martes martes) are subject to national and international conservation legislation throughout most of their European range. Yet population density and abundance estimates, which are a key component of effective conservation management, are lacking in many countries. In this study, a large-scale non-invasive survey was undertaken in 14 forested study sites throughout Ireland to assess variation in pine marten density and abundance. Pine marten hair samples were collected in each study site and analysed using genetic techniques to determine individual identity data. Density and abundance estimates were obtained using spatially explicit capture-recapture models and CAPWIRE. Across all study sites, a total of 93 individual pine marten were identified and captured 217 times. Estimated pine marten density varied from 0 to 2.60 individuals per km² of forested habitat, with all but a single site having estimated densities of ≤1 pine marten per km² of forest habitat. Mean population abundance estimates across all study sites ranged from 0 to 27 individuals. Spatially explicit capture-recapture models on combined data across all 14 study sites provided a mean density estimate of 0.64 (95% CI 0.49–0.81). Combining this with data on the current distribution and estimated area of forest habitat occupied by the species in Ireland, the total pine marten population abundance of pine marten in Ireland was estimated at 3043 (95% CI 2330–3852) individuals. This research has conducted the largest scale investigation of pine marten density and abundance in any part of its global distribution and provided an improved basis for future population assessment and monitoring of this species.     

Trophic and spatial relationships of the pine marten (Martes martes) and American mink (Neovison vison) on mountain rivers of the Southern Urals

The American mink (Neovison vison) and pine marten (Martes martes) are the most common mustelid species in mountain forests of the Southern Urals. The bulk of the diet (85.3%) in the American mink consists of small mammals (35.8%), insects (22.7%), gastropods (14.1%), and fish (12.7%). In the pine marten, the main components comprising 79.6% of the diet are vegetable foods (29.8%), small mammals (27.0%), and insects (22.8%). The low diversity of their food spectra is accounted for by landscape and ecological features of the study region. The abundance of rodents is low, their distribution has a mosaic pattern, and other kinds of food are more abundant near rivers and streams, which explains the preference of both mustelid species for riparian biotopes. The breadth of trophic niches in the pine marten and American mink are 1.67 and 1.62, respectively, and the coefficient of their overlap is 0.75.     

Socio-spatial ecology of pine marten (Martes martes) in conifer forests,Ireland

Understanding the social organisation and spacing patterns of wildlife populations is an important aspect of conservation management and applied science. The present study investigated the spatial ecology of pine marten (Martes martes) inhabiting conifer forests in Ireland, the largest habitat resource available for the species. It represented the first study of pine marten spacing patterns in Irish conifer forests. Pine marten (n?=?7; five males and two females) were live-trapped and radio-tracked for between 4 and 10 months from March 2008 to March 2009. Mean annual home-range estimates (95 % fixed kernel) for males (150.7 ha) were generally larger than those of females (90.2 ha). There was considerable inter-seasonal overlap in home ranges (approx 85 %) with less inter-sexual (12.0 %) or intra-sexual (11.8 %) overlap, although the sample size of individuals for comparison was small. Pine marten home ranges were stable from season to season. Core ranges varied in size from 10.6 to 104.1 ha, and as a mean percentage of home-range area were 22.9 and 42.5 % for males and females, respectively. In terms of forest management, potential under occupancy of available space by pine marten and vulnerability of very small core ranges to clear felling practices needs further research to determine any impacts on individuals and populations.     

Species-Specific Structure of the Frontal Part of the Skull in the Sable (Martes zibellina) and the European Pine Marten (Martes martes)

Biology Bulletin - Comparative analysis of three craniometric traits that characterize the length-to-width ratios in the frontal surface of the skull in the sable and the pine marten was performed....     

A non-invasive genetic method to identify the sympatric mustelids pine marten (<Emphasis Type="Italic">Martes martes</Emphasis>) and stone marten (<Emphasis Type="Italic">Martes foina</Emphasis>): preliminary distribution survey on the northern Iberian Peninsula

The closely related mustelids European pine marten (Martes martes) and stone marten (Martes foina) sympatrically inhabit a large area of Europe. However, given our limited knowledge of their bioecological relationships, their extremely elusive behaviour and the fact that their faeces cannot be distinguished on the basis of morphology alone, it is very difficult to monitor their populations. In this study, we describe a reliable non-invasive polymerase chain reaction (PCR)–restriction fragment length polymorphism (PCR-RFLP) method for distinguishing between M. martes and M. foina based on the analysis of deoxyribonucleic acid extracted from faeces samples. The method was specifically designed to avoid possible interference from potential prey mammals and other sympatric carnivores. The procedure consists of PCR amplifying a mitochondrial D-loop region followed by digesting the resulting 276-bp-long amplicons with the restriction enzymes HaeIII and RsaI. To assess the efficiency of this technique, we conducted a preliminary field study across the potential sympatric distribution areas of both marten species in the northern Iberian Peninsula. Out of 359 faeces samples collected, we identified 80 as specimens from the stone marten and 235 from the pine marten. Unequivocal species identification was thus possible in 88% of the faeces samples collected. These findings reveal the combined use of non-invasive genetic sampling and GIS technology to be a reliable and cost-effective procedure for improving our knowledge of the spatial distributions of sympatric marten species. This protocol could also be used to identify and improve information gaps, to develop effective research and management programmes and in population and landscape genetics studies of marten species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Spatial Niche Segregation of Sympatric Stone Marten and Pine Marten – Avoidance of Competition or Selection of Optimal Habitat?

Coexistence of ecologically similar species relies on differences in one or more dimensions of their ecological niches, such as space, time and resources in diel and/or seasonal scales. However, niche differentiation may result from other mechanisms such as avoidance of high predation pressure, different adaptations or requirements of ecologically similar species. Stone marten (Martes foina) and pine marten (Martes martes) occur sympatrically over a large area in Central Europe and utilize similar habitats and food, therefore it is expected that their coexistence requires differentiation in at least one of their niche dimensions or the mechanisms through which these dimensions are used. To test this hypothesis, we used differences in the species activity patterns and habitat selection, estimated with a resource selection function (RSF), to predict the relative probability of occurrence of the two species within a large forest complex in the northern geographic range of the stone marten. Stone martens were significantly heavier, have a longer body and a better body condition than pine martens. We found weak evidence for temporal niche segregation between the species. Stone and pine martens were both primarily nocturnal, but pine martens were active more frequently during the day and significantly reduced the duration of activity during autumn-winter. Stone and pine martens utilized different habitats and almost completely separated their habitat niches. Stone marten strongly preferred developed areas and avoided meadows and coniferous or deciduous forests. Pine marten preferred deciduous forest and small patches covered by trees, and avoided developed areas and meadows. We conclude that complete habitat segregation of the two marten species facilitates sympatric coexistence in this area. However, spatial niche segregation between these species was more likely due to differences in adaptation to cold climate, avoidance of high predator pressure and/or food preferences by both species than competitive interaction between them.     

Population crash in an invasive species following the recovery of a native predator: the case of the American grey squirrel and the European pine marten in Ireland

In Ireland, the UK and Italy, the invasive North American grey squirrel, Sciurus carolinensis, threatens the survival of the Eurasian red squirrel, Sciurus vulgaris, as the effects of competition and disease almost inevitably lead to total replacement of red squirrel populations. However the results of a recent national squirrel survey suggested that the normally invasive grey squirrel had gone into decline in the Irish midlands, which was anecdotally attributed to an increase in European pine marten, Martes martes, range and numbers. This study aimed to quantify changes in squirrel distribution in Ireland and to investigate the role, if any, of the pine marten in red and grey squirrel population dynamics. A distribution survey of the midlands was carried out which confirmed the grey squirrel population has crashed in approximately 9,000 km² of its former range and the red squirrel is common after an absence of up to 30 years. At landscape level, pine marten and red squirrel abundance were positively correlated, whereas a strong negative correlation between pine marten and grey squirrel presence at woodland level was found to exist. Squirrel demographics were determined by means of live trapping programs which confirmed that the red squirrel in the midlands is now in competitive release and the grey squirrel is present at unusually low density. This study provides the first evidence of a regional grey squirrel population crash and suggests that European pine marten abundance may be a critical factor in the American grey squirrel’s success or failure as an invasive species.     

A species distribution model for pine marten (<Emphasis Type="Italic">Martes martes</Emphasis>) in the least forested region of Europe

Species distribution modelling is a useful technique that provides data on factors that can influence a species range, identify high suitability areas and model future scenarios. The pine marten (Martes martes) has undergone major historical declines in abundance and distribution in Northern Ireland, similar to that which has occurred throughout its range. Currently, the species is in a phase of range expansion in Northern Ireland, in what is the least forested landscape in Europe. To assess the suitability of this environment for pine marten re-establishment, presence only distribution data combined with landcover data at a 10-km scale were used in a species distribution modelling study using Maxent. The results indicated that approximately 32% (4500 km²) of the land area of Northern Ireland had a high probability of pine marten occurrence. Pine marten distribution was positively associated with the extent of conifer forest landcover types, which also had the highest single attribute contribution to the model. Landcover types that were negatively associated with pine marten distribution included the extent of open, dwarf and urban areas.     

Habitat requirements of Eurasian pine marten <Emphasis Type="Italic">Martes martes</Emphasis> in a Mediterranean environment

Evaluating presence and habitat requirements of small carnivores is essential for their conservation. The Eurasian pine marten Martes martes, often described as a habitat specialist associated primarily with forest habitats, has been recently found to live even in patchily wooded country and in shrublands. We evaluated the environmental factors that determine the distribution of the pine marten in a Mediterranean landscape on the island of Sardinia (central Italy). Camera trapping sessions and scat surveys were carried out to assess the presence of the species, then a potential distribution model was developed using ecological niche factor analysis (ENFA), which requires only presence data. The pine marten selected highest altitudes, shrublands, rocky areas, and woodlands, and avoided urban areas and arable lands. Our results indicate that pine marten distribution in our study area is constrained by these variables. The ENFA analysis provided important clues about the distribution range of M. martes and its preferential environmental conditions, updating knowledge of its ecological requirements in Italy.     

Intrapopulation Polymorphism of the Pine Marten (<Emphasis Type="Italic">Martes martes</Emphasis>, Carnivora,Mustelidae) from Tver Oblast

The intrapopulation polymorphism of the pine marten (Martes martes L. 1758) was assessed on the basis of studying five samplings of skulls, three of which were collected on the same territory at different times. The geographical distance between the three sampling areas varied from 60 to 240 km. Study of the material using the phenetic (250 skulls), morphometric (151 skulls), and molecular genetic (21 skin samples) approaches allowed us to characterize the pine marten as a species with a low level of polymorphism. The genetic diversity (π = 0.0069 ± 0.0041 and H = 0.90 ± 0.039) is determined by ancient demographic processes that took place in the Pleistocene and Holocene and are related to the ice-age history of this species, its expansion, and the formation of the population on the territory under study. Low levels of phenetic (μ = 1.48 ± 0.056, h = 0.14 ± 0.033) and morphological (CV = 3.37 ± 0.41) diversity as well as a low level of sexual dimorphism (Isd = 9.4) indicate that the pine marten occupies a specific and relatively narrow ecological niche and is involved in weak competition with smaller mustelid species.