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Recent climate warming is thought to affect the migratory behavior and geographical range shifts of Pipistrellus nathusii. This bat of the European temperate woodland zone is known to migrate up to 1900 km between its breeding and wintering areas where it uses overground roosts for hibernation. New wintering areas of the species have been recorded lately mainly in the cities of Central Europe, largely extending its winter distribution to the north-east. The growing detection of the winter occurrence of P. nathusii has coincided with an increase in mean winter temperatures and urban warming. Our analysis shows that a winter isotherm of −2.5°C acts as a border for the winter occurrence of P. nathusii, and the species uses urban areas, most likely benefiting from the effect of urban heat islands. Accordingly, the island-like pattern of P. nathusii's regular wintering habitats distribution in Central Europe seems to reflect the thermal and structural diversity of the environment. The use of diverse anthropogenic roosts suggests that the species is well-adapted to urban habitats, thus demonstrating its ecological plasticity. [ABSTRACT FROM AUTHOR]

The expensive brain hypothesis predicts that the lowest stable level of steady energy input acts as a strong constraint on a species' brain size, and thus, that periodic troughs in net energy intake should select for reduced brain size relative to body mass. Here, we test this prediction for the extreme case of hibernation. Hibernators drastically reduce food intake for up to several months and are therefore expected to have smaller relative brain sizes than nonhibernating species. Using a comparative phylogenetic approach on brain size estimates of 1104 mammalian species, and controlling for possible confounding variables, we indeed found that the presence of hibernation in mammals is correlated with decreased relative brain size. This result adds to recent comparative work across mammals and amphibians supporting the idea that environmental seasonality (where in extremis hibernation is necessary for survival) imposes an energetic challenge and thus acts as an evolutionary constraint on relative brain size. [ABSTRACT FROM AUTHOR]

Populations of long‐distance migrant birds are declining but it is unknown what role land cover change in non‐breeding areas may be playing in this process. Using compositional analysis, we assessed habitat selection by one such migrant, the Wood Warbler Phylloscopus sibilatrix, at a wintering site in the forest–savannah transition zone in Eastern Region, Ghana. There was a preference for forest, a habitat that is in marked decline at this site. Annual habitat mapping revealed that the area of forest declined by 26% between 2011/12 and 2013/14, mainly through clearance for conversion to arable land. Numbers of birds changed throughout the season, but despite the reduction in the preferred forest habitat, there was no change in the total number of birds recorded at the site over the study period. The number of birds recorded at a point was positively related to the proportion of cleared land, plantation and, to a lesser extent, dense forest within 100 m. Investigation of the fine‐scale habitat preferences of radiotagged Wood Warblers suggested that there was an optimum number of trees, around 66–143 per hectare, at which estimated probability of occupancy was 0.5, falling to a probability of 0.2 at 25 trees per hectare. We suggest that Wood Warblers may be buffered against the loss of forest habitat by their ability to utilize degraded habitats, such as well‐wooded farmland, that still retain a substantial number of trees. However, the continued loss of trees, from both forest and farmland is ultimately likely to have a negative impact on wintering Wood Warblers in the long‐term. [ABSTRACT FROM AUTHOR]

Abstract. A prediction that has gained considerable traction in the American pika (Ochotona princeps) literature is that because of climate change, high mortality is likely to occur in winters of low or early snowmelt and cause extirpation of local populations. The basis for this prediction is the perception that the absence of an insulative layer of snow to protect pikas from severe winter cold temperatures may cause animals to utilize metabolic reserves through excessive thermoregulation before the spring emergence of fresh vegetation, or die directly from exposure to extreme winter temperatures. The Sierra Nevada of east central California experienced its lowest snowfall in recorded history during the winter of 2014/2015. We observed patch occupancy as a proxy for overwinter survivorship of American pikas in the Sierra Nevada during summer 2015 in comparison to baseline populations at the same sites during summer 2014. In summer 2015, pika presence was documented at 36 of 37 sites where pikas had been observed in summer 2014. Contrary to the low snowfall-high mortality prediction, there was no evidence that the nearly total lack of snow caused unusual overwinter mortality in Sierra Nevada pikas. [ABSTRACT FROM AUTHOR]

Eastern North Pacific gray whales make one of the longest annual migrations of any mammal, traveling from their summer feeding areas in the Bering and Chukchi Seas to their wintering areas in the lagoons of Baja California, Mexico. Although a significant body of knowledge on gray whale biology and behavior exists, little is known about their vocal behavior while migrating. In this study, we used a sparse hydrophone array deployed offshore of central California to investigate how gray whales behave and use sound while migrating. We detected, localized, and tracked whales for one full migration season, a first for gray whales. We verified and localized 10,644 gray whale M3 calls and grouped them into 280 tracks. Results confirm that gray whales are acoustically active while migrating and their swimming and acoustic behavior changes on daily and seasonal time scales. The seasonal timing of the calls verifies the gray whale migration timing determined using other methods such as counts conducted by visual observers. The total number of calls and the percentage of calls that were part of a track changed significantly over both seasonal and daily time scales. An average calling rate of 5.7 calls/whale/day was observed, which is significantly greater than previously reported migration calling rates. We measured a mean speed of 1.6 m/s and quantified heading, direction, and water depth where tracks were located. Mean speed and water depth remained constant between night and day, but these quantities had greater variation at night. Gray whales produce M3 calls with a root mean square source level of 156.9 dB re 1 μPa at 1 m. Quantities describing call characteristics were variable and dependent on site-specific propagation characteristics. [ABSTRACT FROM AUTHOR]

The dispersal, population dynamics, and ecological features of the European roe deer at the northern limit of species distribution and also their visits, wintering, and breeding outside the range boundary are discussed. A significant increase in the abundance of roe deer in the northern part of the range and their largescale expansion beyond the historical distribution limit have taken place during the past decade. However, their spread in Karelia and Arkhangelsk oblast is strictly limited, depending primarily on snow depth and duration. Hunting the roe deer as a game species in the region is possible only in the south of Pskov oblast, where habitat conditions are most favorable for it. [ABSTRACT FROM AUTHOR]

Similar to birds, bats also perform long-distance migration between their breeding and wintering sites. In Northern Europe, migratory bat species are often detected along the coastline of the Baltic Sea particularly during migration seasons in the spring and autumn. In spite of regular monitoring of bat migration at coastal sites, the overall distribution of migratory bats in Northern Europe and variability between sites and seasons are still very poorly known. In this study we used automated bat detectors to compare the activity of migratory bat species between coastal and inland monitoring sites along the west coast of Finland (61.5-61.9°N, 21.3−22.3°E). Our main goal was to test whether the activity of migratory bat species is associated with the coastline or whether these species also occur inland. Of migratory bat species observations, 98.6% were covered by Pipistrellus nathusii, which was detected at all our monitoring sites. The activity of the species decreased rapidly, with increasing distance from the coastline towards inland, indicating a sharp activity gradient along the coastline of the Baltic Sea. Because the activity of P. nathusii occurred in migration season and no similar spatial pattern was detected among sedentary species, our results suggest that the aggregation of P. nathusii at the coastline is related to migration as such rather than regular foraging behavior of this species. Our study has direct implications to the wind power planning in Northern Europe. Based on our study we conclude that the impact of wind power on both migratory (namely P. nathusii) and sedentary bat species (namely Eptesicus nilssonii) should be taken into account in wind power planning and impact mitigation in Northern Europe, especially if new wind farms are located along the coastline of the Baltic Sea. When the turbines are located further inland, more attention in the planning process should however be given to the sedentary bat E. nilssonii. [ABSTRACT FROM AUTHOR]

The southern right whale (SRW), Eubalaena australis, was heavily depleted by the whaling in the Southern Hemisphere. In the southwestern Atlantic, studies on SRWs have been concentrated in two main breeding grounds: Península Valdés, Argentina (~42°'S) and Santa Catarina (SC) State, Brazil (~28°'S). To better understand the ecology of SRWs in the region located between these breeding grounds, shore-based surveys were carried out off Torres (29°19'S, 49°43'W), Rio Grande do Sul (RS). Whales were observed in the area between July and October with peaks in August and September. Group sizes were relatively small (x̅ = 1.6; range = 1-3). Distribution in relation to distance from the coast varied from 0.5 to 8.9 km (median = 1.9 km). Unlike in other areas, mother-calf pairs were not observed to occur in shallower waters more often than unaccompanied whales. Mother-calf pairs presented northbound movements to SC more frequently than unaccompanied whales. A comparison of the present data with those from Uruguay and SC revealed that SRWs of different gender/reproductive status may use distinctively the eastern coast of South America. Within these regions, the proportion of mothercalf pairs increases progressively as latitude decreases (from 8% in Uruguay to 58.5% in SC), while the proportion of unaccompanied SRWs presents an opposite trend. This study indicates that RS is an important area for reproduction of SRWs because the three phases (birth, nursing, and mating) proposed for a breeding ground occur there. [ABSTRACT FROM AUTHOR]

The article offers information on the first reported mortalities of Southern right whales Eubalaena (E.) australis in the winters 2013 and 2014 in Southeast Queensland. It mentions that whales encounter anthropogenic threats such as habitat disturbance and degradation. It notes that adult E. australis with broken skull was sighted floating from Wurtulla Beach.

North Atlantic humpback whales ( Megaptera novaeangliae (Borowski, 1781)) are increasing in number, necessitating current data from winter areas for assessing potential interactions with humans. Occurrence patterns of humpback whales wintering off Puerto Rico were investigated to predict where whales aggregate in nearshore areas. Here we describe the relationship between group associations of humpback whales and bathymetric features off western Puerto Rico. Data were collected from 2011 to 2014. Effort consisted of 240.9 vessel h, 13.0 aerial h, and 303.6 h of land observations conducted over 165 days. A total of 197 humpback whale groups were observed with n = 331 individuals: 91 (46.2%) singletons, 67 (34%) dyads, 17 (8.6%) mother-calf pairs, 8 (4.1%) competitive groups, 8 (4.1%) mother-calf-escort groups, and 6 (3.1%) mixed-species associations. A linear regression model supported that group composition correlated with hotspots associated with four bathymetric features. Dyads and competitive groups were dispersed among features in deeper water. Singletons were observed farther from a shelf edge, whereas singing males were closely associated with a shelf edge. Mother-calf pairs occurred nearshore in shallow water; however, when mother-calf pairs were sighted with an escort, they were offshore. This study is especially important ahead of possible removal from the Endangered Species list. [ABSTRACT FROM AUTHOR]

Adverse effects of light at night are associated with human health problems and with changes in seasonal reproduction in several species. Owing to its role in the circadian timing system, melatonin production is suspected to mediate excess nocturnal light. To test this hypothesis, we examined the effect of light pollution on the timing of seasonal reproduction on a strict Malagasy long-day breeder, the nocturnal mouse lemur (Microcebus murinus). We randomly exposed 12 males in wintering sexual rest to moonlight or to a light-mimicking nocturnal streetlight for 5 weeks. We monitored urinary 6-sulfatoxymelatonin concentrations (aMT6s), plasma testosterone concentrations, and testis size, and we recorded daily rhythms of core temperature and locomotor activity. In males exposed to light pollution, we observed a significant decrease in urinary aMT6s concentrations associated with changes in daily rhythm profiles and with activation of reproductive function. These results showed that males entered spontaneous sexual recrudescence leading to a summer acclimatization state, which suggests that light at night disrupts perception of day length cues, leading to an inappropriate photoentrainment of seasonal rhythms. [ABSTRACT FROM AUTHOR]

Amur tigers and Far Eastern leopards are sympatric in the Russian Far East. Different ecological characteristics, such as different resource use, may enable coexistence of these two large predators, as indicated in other tiger–leopard habitats in Asia. We examined the winter food habits of tigers and leopards in the sympatric range in Southwest Primorskii Krai, Russian Far East using feces collected during four winters (2000–01, 2001–02, 2002–03, and 2004–05). Fecal samples were identified as either tiger or leopard by genetic analysis, and we examined 63 and 139 samples of tiger and leopard feces, respectively. We found that leopards preyed on 13 species and tigers on 8 species. Wild boar and sika deer were the most frequently consumed prey for tigers and leopards, respectively. Three ungulates (sika deer, roe deer, and wild boar) appeared to be the essential prey because they provided a large proportion of the relative biomass consumed by tigers (92%) and leopards (87%). Tigers showed a strong preference for wild boar (Jacobs index: +0.55), whereas leopards did not show such a strong preference for any particular ungulate species. Moreover, both species consumed mid-sized carnivores and small mammals, with leopards consuming a more diverse range of prey, including squirrels, rodents, birds, and clams, none of which were identified in the tiger feces. There was a significant difference in the composition of their prey, suggesting resource partitioning between the two predators; however, Pianka's niche overlap index was high (0.77) because both species heavily relied on the three ungulates. Our study suggests that the availability of three different ungulate species, the tigers’ preference for wild boar, and the diverse prey base of leopards contribute to the coexistence of tigers and leopards in this region. [ABSTRACT FROM AUTHOR]

White-nose syndrome (WNS) was first detected in North American bats in New York in 2006. Since that time WNS has spread throughout the northeastern United States, southeastern Canada, and southwest across Pennsylvania and as far west as Missouri. Suspect WNS cases have been identified in Minnesota and Iowa, and the causative agent of WNS ( Pseudogymnoascus destructans ) has recently been detected in Mississippi. The impact of WNS is devastating for little brown bats ( Myotis lucifugus ), causing up to 100% mortality in some overwintering populations, and previous research has forecast the extirpation of the species due to the disease. Recent evidence indicates that remnant populations may persist in areas where WNS is endemic. We developed a spatially explicit model of little brown bat population dynamics to investigate the potential for populations to recover under alternative scenarios. We used these models to investigate how starting population sizes, potential changes in the number of bats overwintering successfully in hibernacula, and potential changes in demographic rates of the population post WNS may influence the ability of the bats to recover to former levels of abundance. We found that populations of the little brown bat and other species that are highly susceptible to WNS are unlikely to return to pre-WNS levels in the near future under any of the scenarios we examined. [ABSTRACT FROM AUTHOR]

The article presents data of one of a multiyear series of marine mammal line-transect surveys in the eastern tropical Pacific with information on sighting data, identification photographs, and biopsies of blue whales. A proposal declaring the Galapagos region as a wintering destination of the eastern South Pacific population (ESP) blue whale population is outlined. The critical role of identifying habitat areas for the implementation of marine protected area (MPA) networks is also tackled.

We investigated density dynamics of three bat flies species (Diptera, Nycteribiidae): Penicillidia monoceros Speiser, 1900, Nycteribia quasiocellata (Theodor, 1966), Basilia rybini (Hurka, 1969) parasitized on two host species: pond bat, Myotis dasycneme (Boie, 1825), and eastern water bat, Myotis petax Hollister, 1912. Females of M. dasycneme have 3.4 (95 % CI 1.4-8.3) times higher odds of being infested, and in 2.4 (1.5-3.7) times higher average number of P. monoceros than males. Similarly, females of M. petax have 1.7 (1.2-2.4) times higher density of N. quasiocellata and/or B. rybini. We hypothesized an existence of host-sex-recognition mechanism in bat flies, providing it fine 'ecological profit' due to sex-biased dispersal among adult host during wintering and the chance to infested a host offspring later (in summer). The decrease (due to mortality or emigration) in density of bat flies can be described as simple harmonic or S-shaped curve, and its 'step' apparently corresponds to time of host pairing. [ABSTRACT FROM AUTHOR]

Before 1990, mass wintering of the noctule bat ( Nyctalus noctula) in Ukraine was known from the Ukrainian Transcarpathia and the south of the country. For the rest of Ukraine, as for other regions of Europe to the north and the northeast, the species was considered a migratory one. Today, the noctule bat is known in winter for 23 (of 25) administrative provinces of Ukraine, and winter colonies have been recorded in most of them. In Ukraine, N. noctula is a seasonal epilithic species, which hibernates mostly in multi-storey buildings serving as cliff-like structures. The retrospective analysis of bat data from Ukraine and adjacent countries shows that new records refer to the expansion of the species' winter range, which occurred during the last decades. The border of the winter range of N. noctula in Eastern Europe now lies at least 500-600 km northward than previously assumed. The analysis of the air temperature datasets demonstrates that warming of winters cannot be the only factor determining this process. Mass appearance of high buildings and roosts associated with them is thought to be an important condition driving the expansion. [ABSTRACT FROM AUTHOR]

High-frequency broadband clicks were recorded from narwhals (Monodon monoceros) off the Uummannaq region, Northwest Greenland, in April 2012 and 2013 while whales were on their wintering grounds in Baffin Bay. Recordings were made on eight different days directly from the pack ice edge or through holes drilled in pack ice floes at approximately 71° N and between 54° to 60° W. Recordings were conducted using a single hydrophone along with a recording system with a sampling frequency of 500 kHz and an Acousonde™ 3B with a sampling frequency of 250 kHz. The energy in the high-frequency narwhal clicks extended up to 200 kHz. Buzzes with inter-click intervals (ICI) down to 3.2 ms were also recorded; however, no whistles were obtained. This is the first time the whole bandwidth of narwhal echo-location clicks has been reported and the first case for which buzzes have been recorded from narwhals at their wintering ground. These data may have implications for conservation, management, and acoustic monitoring techniques in light of ongoing and expected significant increases in anthropogenic sound (e.g., seismic exploration, shipping) in the Arctic. [ABSTRACT FROM AUTHOR]

We initiated the citizen science-based Alaska Bat Monitoring Project in 2004 to investigate the distribution, habitat use, and seasonal ecology of the Little Brown Myotis in Southcentral, Central, and Western Alaska. As of 2012, we received reports of bats from 252 unique locations across the focus area, including Kotzebue, White Mountain, Saint Michael, and the Semidi Islands, which represent significant range extensions for bats in the state. Ninety-seven percent of 111 roosts were located in human structures. Maternity colonies were identified in 48 locations, all in human structures. The majority of observations were reported in late July, August, and September, but we received observations every month of the year. We received reports of bats in 25 unique locations during the winter period from October to April. Winter bats were all associated with buildings unless observed flying outdoors; no hibernacula in natural substrates were documented. Timing and locations of winter observations imply that bats in the most northerly areas are likely non-migratory and overwinter in human structures, while winter observations in Southcentral Alaska suggest both migratory and non-migratory behavior. Despite the limitations and bias inherent in the data set, these reports represent a significant contribution to our understanding of the distribution and ecology of the Little Brown Myotis in Alaska and provide a basis for future directed research efforts. [ABSTRACT FROM AUTHOR]

Although 5 species of bats have been documented in Southeast Alaska, information on species not of the genus Myotis is derived solely from 4 specimens of the Silver-haired Bat (Lasionycteris noctivagans). We acoustically monitored for bat species that produce low frequency echolocation calls (<30 kHz minimum frequency), specifically Hoary Bat (Lasiurus cinereus), Silver-haired Bat, and Big Brown Bat (Eptesicus fuscus) at 40 sites in 16 locations across Southeast Alaska from 2011 to 2013 using passive bat detectors. The Hoary Bat was not previously known from Alaska, but we recorded 25 call files of this species (of 26,151 low frequency bat files) at 5 sites in northern Southeast Alaska (4 mainland sites and 1 site on Chichagof Island); an additional 110 call files were classified as probable Hoary Bat, but were ambiguous. We recorded 3075 call files that contained echolocation calls diagnostic of Silver-haired Bats; no files had characteristics diagnostic of Big Brown Bats. The rest of the low frequency recordings were identified as probable Silver-haired Bat calls, although Big Brown Bats cannot be ruled out due to the extensive overlap of acoustic characteristics between these 2 species. We recorded Hoary Bats almost exclusively during the autumn migration period. By contrast, Silver-haired Bats were detected throughout the summer active season, indicating at least some individuals are resident in Southeast Alaska. Silver-haired Bat activity was greatest at sites on or near the mainland, with most sites showing peaks of activity in spring, suggesting bats from the interior may be overwintering in the region. Winter recordings suggest Silver-haired Bats (and Big Brown Bats if present) are active to some extent during winter in Southeast Alaska. Understanding the distribution and seasonality of Hoary and Silver-haired Bat activity in Southeast Alaska is a critical 1st step toward identifying their habitat requirements and conservation needs in this region. [ABSTRACT FROM AUTHOR]

Depicting the spatial distribution of wildlife species is an important first step in developing management and conservation programs for particular species. Accurate representation of a species distribution is important for predicting the effects of climate change, land-use change, management activities, disease, and other landscape-level processes on wildlife populations. We developed models to estimate the spatial distribution of little brown bat ( Myotis lucifugus) wintering populations in the United States east of the 100th meridian, based on known hibernacula locations. From this data, we developed several scenarios of wintering population counts per county that incorporated uncertainty in the spatial distribution of the hibernacula as well as uncertainty in the size of the current little brown bat population. We assessed the variability in our results resulting from effects of uncertainty. Despite considerable uncertainty in the known locations of overwintering little brown bats in the eastern United States, we believe that models accurately depicting the effects of the uncertainty are useful for making management decisions as these models are a coherent organization of the best available information. [ABSTRACT FROM AUTHOR]

Vessel collision is a threat to many whale species, and the risk has increased with expanding maritime traffic. This compromises international conservation efforts and requires urgent attention from the world's maritime industry. Humpback whales ( Megaptera novaeangliae) are at the top of the death toll, and although Central America is a wintering area for populations from both the Northern and Southern Hemispheres, existing efforts to reduce ship-whale collisions are meager. Herein, we evaluated the potential collisions between vessels and humpback whales wintering off Pacific Panama by following the movements of 15 whales tagged with satellite transmitters and comparing these data with tracks plotted using AIS real-time latitude-longitude points from nearly 1,000 commercial vessels. Movements of whales (adults and calves) in the Gulf of Panama coincide with major commercial maritime routes. AIS vessel data analyzed for individual whale satellite tracks showed that 53% (8 whales) of whales had 98 encounters within 200 m with 81 different vessels in just 11 d. We suggest implementing a 65 nmi Traffic Separation Scheme and a 10 kn maximum speed for vessel routing into the Gulf of Panama during the wintering season. In so doing, the area for potential whale-vessel collisions could be reduced by 93%. [ABSTRACT FROM AUTHOR]

For socially hibernating mammals, the effectiveness of huddling as a means of energy conservation should increase with group size. However, group size has only been linked to increased survival in a few hibernating species, and the relative importance of social structure versus winter conditions during hibernation remains uncertain. We studied the influence of winter weather conditions, social group composition, age-structure, and other environmental factors and individual attributes on the overwinter survival of hoary marmots ( Marmota caligata) in the Yukon Territory, Canada. Juvenile hoary marmot survival was negatively correlated with the mean winter (November to May) Pacific Decadal Oscillation (PDO) index. Survival in older age-classes was negatively correlated with PDO lagged by 1 year. Social group size and structure were weakly correlated with survival in comparison to PDO. The relationship between winter PDO and survival was most likely due to the importance of snowpack as insulation during hibernation. The apparent response of hoary marmots to changing winter conditions contrasted sharply with those of other marmot species and other mammalian alpine herbivores. In conclusion, the severity of winter weather may constrain the effectiveness of group thermoregulation in socially hibernating mammals. [ABSTRACT FROM AUTHOR]

We examine factors affecting the winter range limit of a migrating mammal, the silver-haired bat (Lasionycteris noctivagans), in states surrounding Lake Michigan, the fourth largest freshwater lake in the world. Using 555 citizen-based captures gathered between 1977 and 2016, we show that silver-haired bats overwinter (December–February) as far north as the 45th parallel, in areas roughly demarcated by the −12.2 °C (10 °F) mean daily minimum isotherm for January. Although summering populations adjacent to the lake are dominated by males, wintering animals are predominantly female and presumably migrants from north of Lake Superior. Logistic regression suggests that silver-haired bats are more likely to overwinter in warm areas, in counties near the lake, in urbanized locales, and on the west side of the lake. We believe that these small-bodied, solitary bats are hibernating in buildings and that use of human-made structures has allowed the silver-haired bat to overwinter in regions that are devoid of mines, caves and rock crevices and that are too cold for successful hibernation in trees. Lake Michigan impacts where this animal overwinters, presumably through the moderating influence of the lake on multiple aspects of the surrounding climate and because the shoreline likely is a major migratory pathway. [ABSTRACT FROM AUTHOR]