Fasting in the American marten (<Emphasis Type="Italic">Martes americana</Emphasis>): a physiological model of the adaptations of a lean-bodied animal

The American marten (Martes americana) is a boreal forest marten with low body adiposity throughout the year. The aim of this study was to investigate the adaptations of this lean-bodied species to fasting for an ecologically relevant duration (48 h) by exposing eight farm-bred animals to total food deprivation with seven control animals. Selected morphological and hematological parameters, plasma and serum biochemistry, endocrinological variables and liver and white adipose tissue (WAT) enzyme activities were determined. After 48 h without food, the marten were within phase II of fasting with depleted liver and muscle glycogen stores, but with active lipid mobilization indicated by the high lipase activities in several WAT depots. The plasma ghrelin concentrations were higher due to food deprivation, possibly increasing appetite and enhancing foraging behavior. The lower plasma insulin and higher cortisol concentrations could mediate augmented lipolysis and the lower triiodothyronine levels could suppress the metabolic rate. Fasting did not affect the plasma levels of stress-associated catecholamines or variables indicating tissue damage. In general, the adaptations to short-term fasting exhibited some differences compared to the related farm-bred American mink (Mustela vison), an example of which was the better ability of the marten to hydrolyze lipids despite its significantly lower initial fat mass.     

When recent and evolutionary histories meet: deciphering temporal events from contemporary patterns of mtDNA from fishers (Martes pennanti) in north‐eastern North America

The current spatial distribution of genetic lineages across a region should reflect the complex interplay of both historical and contemporary processes. Postglacial expansion and recolonization in the distant past, in combination with more recent events with anthropogenic effects such as habitat fragmentation and overexploitation, can help shape the pattern of genetic structure observed in contemporary populations. In this study, we characterize the spatial distribution of mtDNA lineages for fisher (Martes pennanti) in north‐eastern North America. The history of fishers in this region is well understood and thus provides an opportunity to interpret patterns of genetic structure in the light of known historical (e.g. recolonization from glacial refugia) and contemporary events (e.g. reintroductions, fragmentation and natural recolonization). Our results indicate that fishers likely recolonized north‐eastern North America from a single Pleistocene refugium. Three genetically distinct remnant populations persisted through the population declines of the 1800s and served as sources for multiple reintroductions and natural recolonizations that have restored the fisher throughout north‐eastern North America. However, the spatial genetic structure of genetic lineages across the region still reflects the three remnant populations.     

Scent marking and social relationships in pine martens (Martes martes)

Scent marking was studied in pine martens (Martes martes) in female-female and male-female pairs. Results show that agonistically dominant individuals generally had higher scent marking frequencies. However, environmental familiarity can modify the social relationship, whatever the previous social experiences, and, consequently, marking activity. Despite important intra-and interindividual variations, the subjects appeared to react to physical and social modifications by an increased marking rate. One factor affecting marking activity in both novel and established pairs was the activity level of the conspecific partner. the data support the hypothesis that pine martens react in the same way to physical and social modifications, but with different response levels. The discussion focuses on possible functions of scent marking. © 1993 Wiley-Liss, Inc.     

黑龙江省老爷岭南部黄喉貂栖息地适宜性评价与廊道构建

黄喉貂(Martes flavigula aterrima)为典型的林栖兽类,对栖息地干扰和破碎化极为敏感,被视为森林生态系统的指示物种。为了科学有效保护该物种,于2020-2021年在黑龙江省老爷岭南部区域布设红外相机642台收集黄喉貂活动位点信息,利用最大熵(MaxEnt)建模方法开展黄喉貂栖息地适宜性研究,探究影响种群生存的关键环境因素,并利用最小成本路径方法构建潜在的种群扩散生态廊道,探讨研究区域黄喉貂种群的栖息地连通性。研究结果表明:(1)MaxEnt模型的受试者工作特征曲线(ROC曲线)评价结果的平均曲线下面积(AUC)值为0.861,能够较好的反映研究区域黄喉貂栖息地适宜性的实际分布情况;(2)本研究利用的13个变量中,距东北虎(Panthera tigris altaica)、东北豹(Panthera pardus orientalis)距离12 km黄喉貂出现概率最高,且贡献率达20.6%,是影响黄喉貂栖息地选择的关键变量,其次坡向(9.9%)、农田(9.5%)、草地(9.0%)、常绿针叶林(8.9%)、道路(7.0%)、河流(6.6%)、居民点(6.1%)和海拔(5.9%)是影响黄喉貂栖息地质量的次要变量;(3)研究区域黄喉貂适宜栖息地面积为793.54 km²,占研究区域总面积的21.4%,主要分布在黑龙江省绥阳林业有限公司的柳桥沟、青山和万宝湾林场。黄喉貂栖息地破碎化严重,因此通过栖息地适宜性分布图获得15块总面积为401.61 km²的核心栖息地,并构建14条生态廊道利于黄喉貂栖息地生态恢复管理。研究综合分析了黑龙江省老爷岭南部黄喉貂栖息地现状及连通性,促进黄喉貂扩散、栖息地的连通性和适宜性。     

Genetic structure of European pine martens (Martes martes), and evidence for introgression with M. americana in England

European pine martens (Martes martes)were once distributed across much ofwestern Europe. A combination of factors, suchas persecution, trapping, and habitat loss haveled to sharp declines in the species' numbersand range and, as such, local populations havebecome more vulnerable to extinction. Toevaluate the influence of these factors on boththe level of genetic variation and populationstructure, we genotyped pine martens fromacross much of their current distribution. Continental M. martes populations werefound to have a higher level of geneticstructure and lower genetic variation thantheir North American sibling species, M.americana, sampled throughout Canada. Thedifferences among mainland populations of thesespecies may lie in greater levels of habitatfragmentation and persecution experienced byEuropean martens, though it is difficult toexclude more ancient processes such as theinfluence of glaciations. Among islandpopulations of the two species, the Scottishpopulation revealed a similar level ofstructure and variation to the M. a.atrata population of Newfoundland, howeverIreland was more differentiated with lessgenetic variation. Our work usingmicrosatellites also extends previous mtDNAevidence for the presence of M. americanahaplotypes in England, raising the possibilityof hybridization with M. martes. Thesefindings may influence current discussions onthe status of English martens and theappropriateness of proposed re-introductions byrevealing that some indigenous martens persistin England, despite the presence of somepotential hybrids in the region.     

Nestbox provisioning in a rural population of Eurasian Kestrels: breeding performance,nest predation and parasitism

The breeding biology of the Eurasian Kestrel Falco tinnunculusin nestboxes in farmland was studied to test for differences between artificial and natural sites. We report on the direct effect of nestbox provisioning on some life-history traits and how nestbox use affects nest predation and parasitism. Five types of nest-sites were available: nestboxes on poles and trees (artificial sites), stick nests on trees, stick nests on pylons and holes in buildings (‘natural’ sites). The Kestrel population increased from 23 pairs in 1993 (prior to nestbox installation) to 55 in 1998 as nestboxes were provided. In general, pairs breeding in trees started to lay later than those nesting in nestboxes on poles or in building holes, but this difference was probably associated with habitat quality rather than nest type. Differences in clutch size were found between nest-sites in some years, and were associated with laying date and, probably, with variation in territory quality. Using only data from successful nests, pairs breeding in nestboxes produce more fledglings than those in building holes or pylons. The frequency of nest predation was higher in natural sites than in nestboxes. The number of fledglings from pairs breeding in nestboxes was higher than from those breeding in old stick nests in trees when all nests were considered. Nestbox provisioning had no effect on the occurrence of the ectoparasite Carnus hemapterus, but chicks from nestboxes showed higher intensity of infection. Our results suggest that nestbox provisioning increases reproductive success and the frequency of nest predation or intensity of parasite infestation in Kestrels.     

Factors affecting harvests of fishers and American martens in northern michigan

Harvest data (e.g., number of animals harvested, trapper effort) are an important source of information for state wildlife agencies to manage harvested furbearers. These data provide evidence to support adapting harvest regulations when necessary. Setting appropriate harvest regulations for fishers (Martes pennanti) and American martens (Martes americana) is critical, as these species often exist at low densities, are sensitive to timber-management practices and trapper-harvest, and experience some level of interspecific predation and competition in sympatric populations. We estimated effects of management (e.g., number of fishers or martens harvested per trapper per season [harvest limit], season length) and extrinsic (e.g., weather, pelt prices) factors on regulated harvests of fishers and martens in the Upper Peninsula of Michigan during 1996–2007. We used generalized linear mixed models in an information-theoretic approach (quasi-likelihood adjusted Akaike Information Criterion [QAIC]) to discern which factors most strongly influenced fisher and marten harvests. For harvest of fishers, the 3 QAIC-best models included harvest limit, season length, and number of trappers, suggesting that regulatory changes within the ranges tested may be implemented to influence harvest. The QAIC-best model (harvest limit) contained 26% of the weight of evidence, and using an independent subset of data, showed no difference between model predictions and harvest data. In contrast, harvest of martens was not strongly influenced by any factors we tested. Possible reasons for a lack of measurable effects while modeling harvest of martens include a low harvest limit (i.e., 1 marten) or incidental harvest of martens by fisher or bobcat (Lynx rufus) trappers. Knowledge of influences on harvest will lead to informed decision-making when managers are setting harvest regulations, particularly for low-density furbearers. © 2011 The Wildlife Society.