Winter Food Research Articles

Cultural heritage in the food traditions of the Sakha people

The paper emphasizes the importance of studying the traditional Yakut/Sakha food as a historical, sociological, psychological and economic factor in the life of the ethnos. The Sakha are one of the most ancient Turkic peoples. Throughout many centuries, the Sakha managed to preserve their food traditions. Life in severe conditions and sharp continental climate affected the specific features of the Sakha nutrition. The Turkic dishes of the nomadic peoples were adapted to the conditions of the North under the influence of the local inhabitants. This special feature is characterized by the use of northern fish and berries as part of nutrition, while the traditional northern meal mainly consisted of horse meat and dairy products. Like many other Turkic-Mongolian peoples, the Sakha subdivide all food into white/ үрүңас [urung as] (dairy food) and black/ хара [khara] (meat food). In their cultural tradition, the Sakha would only begin eating the “black” food in winter after butchering cattle/ идэhэ [ideghe]. In summer, after the national holiday Ыһыах [Ykhyakh] and during the haymaking season, the Sakha would eat “white” food and fish. Vegetables and flour were introduced to them later with the coming of the first Russians to the territory.

SEASONAL CHANGES OF THE MORPHO-BIOLOGICAL CHARACTERISTICS OF BLACK ROCKCOD NOTOTHENIA CORIICEPS (NOTOTHENIIDAE) IN THE ARGENTINE ISLANDS ARCHIPELAGO REGION

Black rockcod Notothenia coriiceps (Nototheniidae) is one of the common fish species of the Argentine Islands Archipelago region, and it is very common in the Southern Ocean waters. So, objective of the original research was to study the seasonal changes of biological characteristics of N. coriiceps individuals. The material was collected during the XII Ukrainian Antarctic Expedition in 2007-2008 using classical methods, specifically by the bottom gear in the ice-free water places from the boat and from the shore, and in winter also from the ice. Pieces of fresh meat and fish were used as bait for gear. The catches were carried out at the depths from 10 to 50 m (mainly at depths of 20-30 m). Result The majority of black rockcod has a standard length of 26,0-30,0 cm (45,3%) and the age of 4-5 full years (84,5%). During the year, the majority of individuals has II stage of development of the gonads (82,9%), however the number of individuals whitch have III and over stage of development has gradually increased from October to January. It was detected that the main diet components of N. coriiceps in the Argentine Islands Archipelago region were fish and crustaceans rarely – mollusks. Two size groups (>25 cm and <25 cm) of black rockod had the same feeding components ratios. In the majority of individuals (67,7%), the gastrointestinal tract was filled poorly (0-1 point). Fat content during the year was predominantly 2-3 points (94,3%). The value of cardiosomatic index during the year has gradually increased from 0,181±0,008 in April to 0,283±0,005 in September and has again decreased to 0,182±0,003 in December. The value of hepatosomatic index has decreased from 2,11±0,10 in April to 1,58±0,06 in November. In December and January the index has increased to 2,66±0,57. The value of fatness by Fulton has decreased from 1,89±0,06 in April to 1,60±0,03 in September, in January it has increased to 1,86±0,52. Conclusions: the character of feeding and development stage of N. coriiceps in the region of the material collection has matched with data from the other researches of the other Antarctic Peninsula regions. In the majority of representatives (66,7%), the gastrointestinal tract was poorly filled (0-1 point), and fat content during the year was predominantly 2-3 points (94,3%). The biological features of N. coriiceps were characterized by the seasonal dynamics, that was associated with the feeding in summer and small amount of food in winter.

Seasonal shift of diet in bank voles explains trophic fate of anthropogenic osmium?

Diet shifts are common in mammals and birds, but little is known about how such shifts along the food web affect contaminant exposure. Voles are staple food for many mammalian and avian predators. There is therefore a risk of transfer of contaminants accumulated in voles within the food chain. Osmium is one of the rarest earth elements with osmium tetroxide (OsO4) as the most toxic vapor-phase airborne contaminant. Anthropogenic OsO4 accumulates in fruticose lichens that are important winter food of bank voles (Myodes glareolus). Here, we test if a) anthropogenic osmium accumulates in bank voles in winter, and b) accumulation rates and concentrations are lower in autumn when the species is mainly herbivorous. Our study, performed in a boreal forest impacted by anthropogenic osmium, supported the hypotheses for all studied tissues (kidney, liver, lung, muscle and spleen) in 50 studied bank voles. In autumn, osmium concentrations in bank voles were even partly similar to those in the graminivorous field vole (Microtus agrestis; n=14). In autumn but not in late winter/early spring, osmium concentrations were generally negatively correlated with body weight and root length of the first mandible molar, i.e. proxies of bank vole age. Identified negative correlations between organ-to-body weight ratios and osmium concentrations in late winter/early spring indicate intoxication. Our results suggest unequal accumulation risk for predators feeding on different cohorts of bank voles.

To Everything There Is a Season: Summer-to-Winter Food Webs and the Functional Traits of Keystone Species.

From a trophic perspective, a seasonal increase in air temperature and photoperiod propagates as bottom-up pulse of primary production by plants, secondary production by herbivores, and tertiary production by carnivores. However, food web seasonality reflects not only abiotic variation in temperature and photoperiod, but also the composition of the biotic community and their functional responses to this variation. Some plants and animals-here referred to as seasonal specialists-decouple from food webs in winter through migration or various forms of metabolic arrest (e.g., senescence, diapause, and hibernation), whereas some plants and resident animals-here referred to as seasonal generalists-remain present and trophically coupled in winter. The co-occurrence of species with divergent responses to winter introduces seasonal variation in interaction strengths, resulting in summer-to-winter differences in trophic organization. Autumn cooling and shortening day length arrests primary productivity and cues seasonal herbivores to decouple, leaving generalist carnivores to concentrate their predation on the few generalist herbivores that remain resident, active, and vulnerable to predation in winter, which themselves feed on the few generalist plant structures available in winter. Thus, what was a bottom-up pulse, spread among many species in summer, including highly productive seasonal specialists, reverses into strong top-down regulation in winter that is top-heavy, and concentrated among a small number of generalist herbivores and their winter foods. Intermediate-sized, generalist herbivores that remain active and vulnerable to predation in winter are likely to be keystone species in seasonal food webs because they provide the essential ecosystem service of turning summer primary productivity into winter food for carnivores. Empirical examination of terrestrial mammals and their seasonal trophic status in the boreal forest and across an arctic-to-tropics seasonality gradient indicates seasonal specialization is more common among herbivores, small body sizes, and in regions with intermediate seasonality, than among carnivores, large body size, and regions where summers are very short or very long. Better understanding of food webs in seasonal environments, including their vulnerability and resilience to climate change, requires a multi-season perspective.

Effects of agri-environmental habitat provision on winter and breeding season abundance of farmland birds

Farmland bird populations continue to show declines in spite of over 20 years of research and implementation of agri-environmental schemes (AES) intended to reverse this. Although it is well known that provision of winter food resources can attract farmland birds, there is continuing uncertainty over the ability of AES to provide tangible benefits for target species in terms of increased abundance. Answering these questions is hampered by interannual fluctuations in bird populations and the mobility and territoriality of farmland birds, which have complicated the interpretation of previous studies.We monitored birds for five years on a large arable estate in central England managed under varying levels of AES uptake (low level uptake of simple and widely applicable AES options, more extensive uptake of more complex AES options), and two control treatments (on-site and off-site). Bird abundance in winter and both total abundance and number of territories in the breeding season were calculated from monthly visits to 16 transects.Several species showed significantly higher winter abundance on AES treatments, particularly granivorous species (e.g. reed bunting, yellowhammer, linnet). Many other species (e.g. blackbird, chaffinch, robin) also showed significant differences in winter abundance between treatments on the estate and off-site controls. In the breeding season, linnet, reed bunting, goldfinch and combined granivorous birds showed higher abundance or number of territories on AES treatments compared to on-site controls. For most other species the differences were only significant between treatments on the estate and off-site controls. Independently of AES treatment, a lower coverage of cereals or greater Shannon diversity of crops in the local landscape also had a positive effect on the abundance of many species.Our results suggest that well-implemented AES can significantly enhance local populations of both farmland specialists of conservation concern and generalist species. Our results also show that, in many cases, these effects were only demonstrable at the farm scale, in comparison with off-site controls. This is probably due to high levels of movement and dispersal of birds resulting in a farm-scale spill-over of beneficial effects of agri-environment measures. Our results therefore highlight the importance of thinking beyond the single-farm scale when designing schemes or studies for monitoring the effectiveness of AES, and the importance of selecting appropriately located controls.

Seascape genetics of a flatfish reveals local selection under high levels of gene flow

Local adaptation is often found to be in a delicate balance with gene flow in marine species with high dispersal potential. Genotyping with mapped transcriptome-derived markers and advanced seascape statistical analyses are proven tools to uncover the genomic basis of biologically relevant traits under environmental selection. Using a panel of 426 gene-linked single nucleotide polymorphisms (SNPs), we scanned 17 samples (n¼539) of sole (Solea solea L.) from the Northeast Atlantic Ocean and applied a node-based seascape analysis. Neutral loci confirmed a clear distinction between the North Sea–Baltic Sea transition zone and the other Eastern Atlantic samples. At a more subtle level, the latter unit split in an English Channel and North Sea group, and a Bay of Biscay and Atlantic Iberian coast group. A fourth group, the Irish and Celtic Sea, was identified with 19 outlier loci. A pattern of isolation by distance (IBD) characterized the latitudinal distribution. Seascape analyses identified winter seawater temperature, food availability and coastal currents to explain a significant component of geographically distributed genetic variation, suggesting that these factors act as drivers of local adaptation. The evidence for local adaptation is in line with the current understanding on the impact of two key ecological factors, the life-history trait winter mortality and the behaviour of inshore/offshore spawning. We conclude that the subtle differentiation between two metapopulations (North Sea and Bay of Biscay) mirrors local adaptation. At least three genomic regions with strong population differentiation point to locally divergent selection. Further functional characterization of these genomic regions should help with formulating adaptive management policies.

Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer.

When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April-May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these 'shore' bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These 'ice' bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt.

Not only mosses: lemming winter diets as described by DNA metabarcoding

The temporal dynamics of most tundra food webs are shaped by the cyclic population dynamics of lemmings. While processes during winter may be behind the recent disruptions of lemming cycles, lemming winter ecology is poorly known. We present here the first DNA metabarcoding data on the winter diet of Norwegian lemmings (Lemmus lemmus), based on feces collected after a winter of population increase. Prostrate willows, mosses, and graminoids dominated the species winter diet, indicating that the conventional idea of lemmings as moss-specialists should be revised. The behavior of lemming-plant models in theoretical studies is conditional on the assumptions of mosses being their main winter food item. As shrubs have been excluded from the framework of these models, incorporating them in future modeling studies should nuance our understanding on how plants affect lemmings. We also sampled diet of a few individuals found dead on top of the snow. These individuals had relatively empty stomachs and had, prior to death, relied heavily on mosses. This apparent lack of abundant good quality indicates spatial heterogeneity in local food availability during the population increase phase.

Colonization of the Beaufort Coastal Plain by Beaver (<i>Castor canadensis</i>): A Response to Shrubification of the Tundra?

A consequence of rapid global warming has been the shrubification (increase in shrub abundance, cover, and biomass) of arctic and alpine tundra ecosystems. Shrubification is likely a key driver of predicted and observed changes in the biodiversity of the Arctic. The American Beaver (Castor canadensis) has a vast distributional range, covering most of north America below the tree line; however, it has not been recorded in tundra habitat of the Beaufort Coastal Plain of Yukon and Alaska. in 2015, we observed a beaver dam, lodge, and winter food cache on the Babbage River in Ivvavik National Park, Yukon, Canada. Local Inuvialuit hunters first observed beavers on two rivers immediately east of the Babbage River in 2008 and 2009. Together, these are the first observations of beavers on the Beaufort Coastal Plain and indicate initial attempts at colonization. Colonization of the Beaufort Coastal Plain by beavers may have been facilitated by shrubification of river valleys on the tundra of northern Yukon and adjacent Alaska, which is a consequence of rapid climate warming in the western Arctic.

Impact of temperature and nutrient dynamics on growth and survival ofCorbicula fluminea: A field study in oligotrophic Lake Constance

The invasive clam Corbicula fluminea was first recorded in Lake Constance (Germany) in 2003 and subsequently established high population densities at various locations in the lake. In 2010, four standardized field experiments were conducted in Lake Constance, one in each season, to investigate seasonal changes in somatic growth and survival of C. fluminea at different water depths. Somatic growth and survival of the clams were related to seasonal variations in water temperature and seston characteristics, that is, phytoplankton species composition and essential nutrient concentrations, and to the elemental and biochemical composition of clam tissues using principal component analyses and regression models. The field experiments revealed that somatic growth and survival of C. fluminea in Lake Constance were primarily determined by water temperature. In winter, low temperatures (<5°C) and low food supply resulted in high mortality and zero growth. Positive somatic growth rates were recorded in the lake throughout the growing season, when the water temperatures exceeded 10°C. Other seston variables, that is, particulate organic carbon content, phytoplankton species composition, and the elemental (nitrogen, phosphorus) and biochemical (fatty acids, sterols) nutrient composition were of minor importance for growth and survival of C. fluminea in oligotrophic Lake Constance. In parallel to the field experiments, standardized laboratory growth experiments were conducted to assess the effects of temperature on clam growth and survival at high food quantity and quality. The results from the laboratory experiments confirmed the conclusion that somatic growth and survival of C. fluminea in Lake Constance were primarily determined by water temperature. Our data suggest that further spread of C. fluminea may be supported by climate change, because milder winter temperatures and an earlier onset of thermal stratification in spring may reduce winter mortality and thereby extend the growing season for C. fluminea.

Effects of density, season, and food intake on sika deer nutrition on Yakushima Island, Japan

AbstractSika deer (Cervus nippon) suffer severe winter food limitation in northern Japan; however, plant food resources are available during winter in southern Japan and, consequently, deer nutritional status may not decrease there. To test this hypothesis, we measured seasonal changes in Riney's kidney fat index (RKFI) and stomach intake in 74 culled deer individuals from five areas with different deer densities on Yakushima Island, Japan. The average RKFI differed significantly among populations and ranged from 22.91 ± 11.91 to 76.23 ± 15.99. There was no significant correlation between RKFI and deer density. The total fresh weight of rumen contents also differed significantly among populations, ranging from 0.51 to 3.51 kg. Food intake and RKFI exhibited an L‐shaped distribution in the vicinity of a town ranch. However, we found that food intake had a significantly positive effect in populations at the other four locations, suggesting that changes in nutritional status were related to the quantity of deer rumen contents. Neither deer density nor season were significantly correlated with RKFI values. The average RKFI values exceeded 20 in all five locations. These findings indicate that the deer were not in a poor nutritional condition even in high density areas of &gt;70 head/km2, which supports the above hypothesis. Notably, food intake varied among individuals in the same area, but was independent of body weight and age, which suggests that food selectivity differs between deer individuals.

Review of the Masked Bobwhite Recovery Effort

The masked bobwhite (Colinus virginianus ridgwayi) was discovered near Sasabe, Sonora in August 1884. Excessive grazing coupled with prolonged drought during the 1890s caused habitat degradation and extirpation of the species in the United States by 1912. The decline of the bobwhite population in Mexico happened later due to similar circumstances. Livestock grazing was not pervasive until the 1940s-1950s in Sonora. The subspecies was thought to be extinct in Mexico by 1960. However, in 1964 a population was discovered between Benjamin Hill and Hermosillo, Sonora. The Buenos Aires National Wildlife Refuge (NWR) was established in 1985 for the re- establishment of the masked bobwhite. There have been four components to the masked bobwhite program on the refuge: captive rearing, release of birds into suitable habitat, habitat manipulation, and cooperation with Mexico. Approximately 98% of the masked bobwhites in the world are in captivity at Buenos Aires NWR and are housed in an indoor facility in Arivaca, Arizona. At that facility the birds are paired by a geneticist and up to 120 pairs are bred each year. Eggs are incubated and hatched and birds are either retained as future breeding stock or prepared for release. Overall, . 31,000 captive-reared bobwhites have been released in the Altar Valley, Arizona with . 21,000 being released on the refuge alone. To date they have not been self- sustaining. Preparation for release includes placing birds in flight pens where they remain for several weeks to a few months to gain exposure to native foods, experience raptor pressure, and become strong flyers. A soft release is normally used with birds being introduced to their new habitat from the confines of a small release pen on-site. A new parent-reared technique is currently being tried and promises improvement in wildness of released birds. This technique limits exposure of bobwhite family groups to humans and other bobwhite family groups until day of release. The bobwhite, as an edge species, needs early successional vegetation, diversity of grasses and forbs, and leguminous shrubs capable of providing cover and winter food. Traditionally, prescribed fire has been the primary management tool used by refuge personnel to improve habitat for masked bobwhites. Currently, Buenos Aires NWR is applying soil aeration treatments in uplands, revegetating with native plant species, constructing brush piles, and converting velvet mesquite (Prosopis velutina) woodlands to grasslands to promote bobwhite habitat. Work with Mexico has involved cooperation with the Mexican government, private ranchers, Mexican biologists, and zoological facilities to implement bobwhite surveys, establish conservation easements, and enhance habitat.

Formulation of an Optimum Winter Food-Patch Mix for Bobwhite Quail

Many state game agencies are seeking to improve winter quail food and habitat by means of artificial food-patch plantings. The objective of such plantings is to increase the limited supplies of nutrients available to quail in late winter. Desirable qualities of food species included in the seeding mixture are: low seeding cost, high nutrient and energy content, persistent seeds, and cultivation ease. Presently used mixtures have been formulated in the absence of detailed nutritional analysis and cost-minimization techniques. This paper seeks to demonstrate the utility of modern operations-research technology in such decisions by outlining the procedures for determining the composition of an optimum food-patch mix. This mix will meet nutrient and cultivation requirements at a least-possible cost per acre of food planting. Although a solution is presented, the emphasis of the paper is on the method for obtaining such a solution.

Seed Availability Within Food Plots and Native Vegetation Areas on a Longleaf Pine Site in Southeastern Louisiana

The lack of late winter foods has been hypothesized as a limiting factor for northern bobwhites in Louisiana pinelands. We determined January seed availability within food plots (rectangular and strip) and native vegetation areas on a longleaf pine site. Planted sites had considerably more seed available than native vegetation sites. However, most seeds were those of native grasses and sedges and not agricultural crops.

Body Fat Content of Bobwhites in Relation to Food Plantings in Kansas

A wildlife habitat improvement program was initiated on the Fort Riley Military Reservation in 1961 to increase winter food supplies for bobwhite quail (Colinus virginianus). As part of an ongoing evaluation of this program, 164 bobwhite quail were collected during the fall and winter of 1968-72 for fat analysis. Fat content in carcasses of birds collected <600 m from a food plot was compared with fat content of birds collected>900 m from a food plot. During winter months, birds collected near a food plot were significantly (P<0.10 to P<0.05) heavier than birds not having access to a food plot. Fat content of birds close to a food plot was likewise greater (P<0.10 to P<0.01) than fat content in birds not using food plots. Calculations indicate that birds close to food plots have sufficient energy reserves to provide a 79% greater protection against brief periods of food deprivation than birds far from a food plot. Fat energy reserves alone in a quail close to a food plot could provide sufficient energy for 2.0 days of survival whereas quail far from food plots contained fat energy reserves sufficient for only 1.1 days of survival. Reserve energy for animals is stored in the body mainly in the form of fatty acids. The quantity of stored reserve energy (fat) may be critical to the animal's survival during periods of food scarcity or extremely cold weather. Much work has been done on fat content, composition, and regulation in songbirds (8, 9, 10, 11, 12, 15, 16, 23, 24). Only recently has any attention been given to body fat reserves of wild gallinaceous birds under natural conditions. West and Meng (25) reported on the relationship of total fat and fatty acid composition to diet of willow ptarmigan (Lagopus lagopus) in Alaska while Moss and Lough (14) presented similar data for 3 species of grouse in Scotland. Almost no attention has been given to fat reserves of bobwhite quail even though it is known that fat reserves may be essential for bird survival during periods of dietary stress (15, 23 and others). The most recent book on bobwhite quail (22) does not even discuss the importance of maintaining adequate fat reserves in quail for winter survival and spring breeding. In fact, not until only very recently has any attention been focused on basic energetics of bobwhite quail (3). Earlier I included a small amount of body-fat data

Influence of Food Plots on Nothern Bobwhite Movements, Habitat Use, and Home Range

Natural resource managers at the Fort Riley Military Reservation in Kansas have established plantings to provide winter food for northern bobwhites (Colinus virginianus) since 1959. These food plots have the potential for reducing movements and home range sizes of bobwhites during winter because birds should apparently need to forage over less area to obtain sufficient food. To determine if this was occurring, we conducted a 3-year radio telemetry study of bobwhites on Fort Riley. We equipped 511 bobwhites with radio transmitters and followed their movements and habitat use from October through March, beginning in 1994. Daily movements of bobwhites near food plots varied by field season and study site, but generally did not differ significantly between food plot and non-food plot areas. Home ranges of bobwhites did not differ significantly between food plot and non-food plot areas, study site, or field season. Prairie habitat always was used significantly less than its proportional availability by bobwhites. Food plots were used significantly more than their proportional availability during 2 of 3 field seasons. Habitat use by bobwhites on the 2 study sites differed between food plot and non-food plot areas.

Winter Food Habits and Preferences of Northern Bobwhites in East Texas

During late winter, 1994 and 1995, we investigated food habits and preferences of northern bobwhites (Colinus virginianus; hereafter, bobwhites) collected on forested lands in east Texas. Crops for bobwhites were collected from areas under 3 management regimes, namely intensively managed for bobwhites (QMA) (i.e., tree basal area reduced, annually burned, numerous multi-stage food plots, etc.), extensively managed for timber and wildlife (NBS) (i.e., burned every 3-5 years, scattered 2-stage food plots with corn feeders), and unmanaged for wildlife (i.e., burned every 5-7 years). With years pooled, partridge pea (Cassia fasciculata), Hercules club (Zanthoxylum clava-herculis), and pine (Pinus spp.) seeds, and clover leaflets (Trifolium spp.) comprised 93% by weight of foods of 79 bobwhites foods on QMA. On NBS, 81% of 40 bobwhite diets was butterfly pea (Centrosema virginianum), browntop millet, pine, wild bean (Strophostyles spp.), and corn seeds and clover leaflets; millet and corn were from food plots and feeders, respectively. For unmanaged areas, 79% of 19 bobwhite diets was butterfly pea, rush (Juncus spp.), pine, partridge pea, and American beautyberry (Callicarpa americana) seeds, and clover leaflets. Top-ranked food items on QMA were pine, hairy vetch, and Hercules club seeds in 1994 and butterfly pea, partridge pea, and wax myrtle (Myrica cerifera) seeds in 1995 (P < 0.05). On NBS, hawthorn (Crataegus spp.) and beautyberry seeds were top-ranked in 1994 as were kobe lespedeza, wild bean, and butterfly pea seeds in 1995. On unmanaged areas, butterfly pea and partridge pea seeds and clover leaflets were highest ranked in 1995. On forested lands, activities (e.g., disking, burning, establishing food plots) which provide seed-bearing plants, especially legumes, and clover greenery benefit bobwhites.

Trophic overlap between wolves and free-ranging wolf [formula omitted] dog hybrids in the Apennine Mountains, Italy

Hybridization between wolves (Canis lupus) and domestic dogs (Canis familiaris) can represent a threat to wild populations via genetic introgression and ecological competition. Therefore understanding the ecological role of hybrids may be crucial for developing appropriate conservation strategies.The Italian wolf population has a peculiar genetic composition due to a long-lasting geographic isolation. Nowadays, however, its genetic integrity is threatened by the spread of canine genes as a result of the hybridization with stray dogs in the wild.The aim of the present study was to gain insights into the ecological role of free-ranging wolf–dog hybrids by investigating their winter food habits in comparison with wolves in a mountain area of Central Italy. Levels of genetic introgression from the dogs were assessed in two adjacent areas occupied by up to five different packs by analyzing non-invasive samples and carcasses collected therein with a set of uniparental and bi-parental molecular markers.The obtained results enabled us to classify the two areas as ‘hybrid’ and ‘wolf’ areas based on their level of genetic introgression.Trophic niche and similarity/dissimilarity analyses did not detect significant difference in the diet between the two areas: in both of them, wild boar was the main prey, followed by roe deer. Furthermore, the same age/body mass classes of the two ungulates were selected by wolves and hybrids. Our findings confirmed wolf–dog hybrids as potential competitors for wolves. Further studies on other aspects of their biology and ecology are recommended in order to better estimate the impact of hybridization on natural wolf populations.

Concentrating or scattering management in agricultural landscapes: Examining the effectiveness and efficiency of conservation measures

A key issue in conservation is where and how much management should be implemented to obtain optimal biodiversity benefits. Cost-effective conservation requires knowledge on whether biodiversity benefits are higher when management is concentrated in a few core areas or scattered across the landscape, and how these effects vary between species. To address these questions, we examined species-specific behavioural responses of over-wintering farmland birds to enhanced seed availability. In a two-year experiment we first examined the relationship between landscape-scale seed availability and farmland bird density. Then we investigated the relative resource delivery (difference in bird densities between landscapes with and without additional management) and the efficiency (number of individuals supported per unit management) of conservation actions, both at the landscape-scale (ca 100ha) and at the scale of the conservation measures (3.6ha). The conservation actions were targeted towards ten seed-eating farmland bird species, but we also considered the responses of seven non-targeted and more generalist seed-eating species, seven species that are less dependent on seeds and three species of birds of prey. We found a positive relationship between bird density and landscape-scale seed availability for eleven species and, for four of these species, the slope of this relationship changed before and after a threshold seed density. For two seed-eating specialists, the number of individuals using conservation patches declined with landscape-scale seed availability. In addition, we found that the relative resource delivery declined with landscape scale seed availability for three seed-eating specialists and was independent of landscape-scale seed availability in four other species. Our results suggest that farmland specialists may benefit most from winter food additions if conservation actions result in high landscape-scale seed availability. This may be achieved by concentrating conservation measures or by establishing measures in areas with high baseline seed availability. By contrast, species that can utilize a wider range of habitats and resources may benefit more from scattering measures across larger areas. Therefore, optimal management for the full range of farmland birds in wintertime may require a combination of core areas with concentrated management and more widely distributed smaller patches of conservation measures.

Evaluation of winter food quality and its variability for red deer in forest environment: overwintering enclosures vs. free-ranging areas

AbstractPopulations of European ungulates have grown substantially over recent decades, resulting in considerable environmental and socio-economic impacts. Availability and quality of natural and supplemental food sources are among the main factors driving their population dynamics. Detailed knowledge of food quality of management-targeted species is therefore of primary importance for their successful management. The main aim of this study was to evaluate winter food quality and its variability for an important ungulate species in the Czech Republic - i.e. red deer, using faecal indices (faecal nitrogen, faecal acid detergent fibre, faecal neutral detergent fibre) and near infrared reflectance spectroscopy. We compared food quality for red deer and its possible differences between overwintering enclosures (i.e. fenced areas where red deer spend harsh winter conditions) and neighbouring unfenced free-ranging areas within two study areas. The results obtained showed that winter food quality and its variability for red deer are of different quality and variability in the overwintering enclosure and neighbouring free-ranging area. The observed differences in concentrations and amounts of variation of faecal indices are most probably related to animal densities at individual study areas. Wildlife managers should therefore keep animals in overwintering enclosures at moderate densities and to provide high quality forage to all individuals in order to balance nutrition of both the individuals inside and outside the enclosures. Nevertheless, further studies are needed in order to provide deeper knowledge on red deer food quality and its variability in space and time.