Rest Sites Research Articles

Daily Rest-Site Selection and Use by the Japanese Dormouse

We radiotracked 23 Japanese dormice (Glirulus japonicus) in a natural oak forest and a larch plantation to locate their daily rest sites. In 363 tracking days, 123 rest sites were used, 72% in trees and 28% in shallow underground sites or a rock crevice. Nest boxes and tree cavities were the most frequently used rest sites in trees. Natural arboreal rest sites and nest boxes were used regularly by individual dormice, whereas most underground rest sites were used for only 1 day. Nest boxes and underground rest sites were used more frequently in the larch plantation than in the oak forest. Males used nest boxes more than underground rest sites, whereas females regularly used the same natural arboreal rest sites. Dormice had large home ranges relative to their body mass. Males had larger home ranges and moved for longer distances at night than did females. A close relationship between rest-site use and daily torpor was apparent; nesting material was not found in natural rest sites used only once, and dormice frequently changed their rest sites.

Using a Remote Technology in Conservation: Satellite Tracking White‐Naped Cranes in Russia and Asia

Abstract: We investigated the application of satellite tracking to the conservation of cranes and other waterbirds and the necessity of international cooperation in the conservation of migratory species. Using satellite tracking, we followed 11 White‐naped Cranes (Grus vipio) on migration from their breeding grounds in eastern Russia to their wintering grounds in China and Japan. From 1991 to 1993, we captured cranes with the aid of helicopters and attached satellite transmitters (platform transmitter terminals) to captured birds via a harness system. We tracked cranes for 156 days on average, across 2558 km, and obtained an average of 339 locations per crane. Cranes migrated over 8–90 days. During migration, birds spent 1–30 days at 4–12 rest sites. Cranes wintered at two main sites: Poyang Lake, China, and Izumi, Japan. All seven cranes migrating to the Poyang Lake area rested at the Yellow River delta–Bohai Bay, China, and all three traveling to Izumi rested in the Demilitarized Zone on the Korean Peninsula. Other important rest sites were marshes around the Wulagai River, Huainan, Hu‐Lun Lake, Linyi, Tangshan, the Three Rivers (Sanjiang) Plain, Tianjin, and the Xar Moron River, all in China, and Lake Khanka–Xinghai at the border of China and Russia. The habitats resting cranes used most frequently were plains, including upland areas, marshes, and rivers. Although nature reserves exist at the two main wintering sites of Poyang Lake and Izumi, rest sites used by cranes were poorly protected. Even when areas used by cranes for resting or wintering were included in nature reserves, reserves were threatened by human encroachment and development. To ensure that cranes can continue to migrate successfully, it is crucial that the establishment of reserves continues at important rest areas and that the areas covered by reserves at wintering sites be extended to include more of the areas utilized by cranes. Also, development and human disturbance should be minimized in reserve areas. Because long‐distance migrant birds, including cranes, range over such large areas, conservation of these organisms and their habitats necessitates multinational communication and cooperation.

Changes in red fox habitat preference and rest site fidelity following a disease-induced population decline

The habitat preferences of red foxesVulpes vulpes (Linnaeus, 1758) in Bristol, UK, were compared during periods of high and low population density following an outbreak of sarcoptic mange (Sarcoptes scabiei). These periods are termed ‘pre-epizootic’ and ‘post-epizootic’, respectively. Habitat preferences were compared between periods during nocturnal activity and diurnal inactivity using compositional analysis. Back gardens were the most preferred habitat for pre-epizootic foxes during periods of activity; back gardens and allotment/woodland habitats were equally preferred by post-epizootic foxes, with a trend for allotment/woodland to be the most favoured. During periods of inactivity, pre-epizootic foxes selected back gardens for diurnal rest sites, compared with allotments/woodland in the post-epizootic period. Post-epizootic foxes also showed a significant decrease in rest sitefidelity, such that they were very unlikely to re-use a rest site more than once. In comparison, pre-epizootic foxes were often very faithful to one or a small number of sites. Such changes in habitat preference and rest site fidelity could have been facilitated by: (1) changes in food availability, (2) a decrease in intra-specific competition, (3) the requirements of defending larger territories post-epizootic, or (4) an avoidance of habitats that might increase the likelihood of mange transmission. The management implications of these results are discussed.

Muon studies of simple oxalate systems

Oxalates are widely found in nature and are of importance in many industrial, scientific and technological fields. The dihydrate α-oxalic acid is known to possess an unusually long central C–C bond for a neutral, closed shell molecule as a result of electron density residing in the σ* orbital, whilst the acidic protons are strongly bound into a hydrogen-bonded network with co-crystallised water. Implantation of positive muons into the dihydrate and the anhydrous sodium oxalate was found to yield considerably different effects, with the oxalic acid response predominantly due to diamagnetic muon rest sites, dominated by proton interactions. In contrast, muoniated radicals corresponding to addition at both the carbon and oxygen sites were observed in the anhydrous sodium salt, with the diamagnetic fraction coupling to the quadrupolar 23Na nuclei at low field.

Effects of agricultural activities and best management practices on water quality of seasonal prairie pothole wetlands

Long-term effects of within-basin tillage can constrain condition andfunction of prairie wetlands even after uplands are restored. Runoff wassignificantly greater to replicate wetlands within tilled basins with orwithoutvegetated buffer strips as compared to Conservation Reserve Program restorationcontrols with revegetated uplands (REST). However, mean water levels for nativeprairie reference sites were higher than for REST controls, becauseinfiltrationrates were lower for native prairie basins, which had no prior history oftillage. Nutrient dynamics changed more in response to changes in water leveland vegetation structure than to increased nutrient inputs in watershed runoff.Dissolved oxygen increased between dry and wet years except in basins or zoneswith dense vegetation. As sediment redox dropped, water-column phosphatedeclined as phosphate likely co-precipitated with iron on the sediment surfacewithin open-water or sparsely vegetated zones. In response, N:P ratios shiftedfrom a region indicating N limitation to P limitation. REST sites, with densevegetation and low DO, also maintained high DOC, which maintains phosphate insolution through chelation of iron and catalysis of photoreduction. Referencesites in native prairie and restored uplands diverged over the course of thewet-dry cycle, emphasizing the importance of considering climatic variation inplanning restoration efforts.

Roosting of Ducks on Open Water: Resting Site Selection in Relation to Safety.

Roost site selection of ducks in relation to safety was investigated at 26 ponds from December 1992 to February 1993 and from December 1993 to January 1994 in northern Chiba Prefecture, central Japan. The degree of safety was evaluated as the size of the safe range. The escape distance (D) between the first individual escaping and the observer was estimated, based on five experiments on the Spot-billed Duck Anas poecilorhyncha the most common species in the study area. I subtracted an area of periphery (unsafe area: width D: 29.2 m from the accessible waterside) from the total area of each pond. The remaining water surface was defined as the safe range. Ten species, including eight dabbling ducks and two diving ducks, were observed at 17 ponds. The total areas and the safe ranges at the 17 ponds with dabbling ducks were significantly larger than at those nine ponds without them. A similar tendency was detected between the seven ponds with diving ducks and the 19 ponds without them. The number of dabbling ducks was positively correlated with the size of the safe range; however no such relationship was detected between the number of dabbling or diving ducks and the total area, or between the number of diving ducks and the size of the safe range. These differences seem to be related to the utilization patterns of the ponds between ducks with different foraging habits. The dabbling ducks utilized the ponds only for resting, while the diving ducks used them as resting and foraging sites. The safe range is a useful index for representing the safety of a roost.

Roosting of Ducks on Open Water: Resting Site Selection in Relation to Safety

Roosting of Ducks on Open Water: Resting Site Selection in Relation to Safety

Flexible spatial organization of urban foxes, Vulpes vulpes, before and during an outbreak of sarcoptic mange

The social and spatial organization of urban fox groups prior to and during an outbreak of sarcoptic mange was compared with predictions derived from the resource dispersion hypothesis (RDH). We investigated the availability of three key resources. Neither daytime rest sites nor breeding sites appeared to be limited in availability. The availability of food deliberately supplied by local householders was examined by questionnaire surveys. The daily and weekly amount of food supplied was greatly in excess of the minimum requirements of a pair of foxes, but was consistent between territories. The availability of this food source increased markedly as a result of more people feeding the foxes. In agreement with the RDH, group size prior to the outbreak of mange increased from 2.25 animals (N=4) to 6.57 animals (N=7). Before the outbreak of mange, two territories were divided. Increased scavenge availability on smaller territories may have promoted these changes. Excluding these spatial changes, territories were very stable between years. After the outbreak of mange, group size declined as a direct result of mange-induced mortality. Surviving animals increased their ranges only after neighbouring groups had died out. Ranges did not increase in size in response to a decline in food availability. Nor were the increases in range size associated with the relinquishment of parts of the existing territory. These postmange changes are contrary to the RDH. Three factors may have promoted these changes: the elimination of interstitial space, the forced dispersal of young or future division of the territory.

The red fox (Vulpes vulpes) in Saudi Arabia: loose‐knit groupings in the absence of territoriality

AbstractAdaptations to extreme environmental conditions were investigated in a detailed study of red foxes Vulpes vulpes inhabiting a desert region of Saudi Arabia. Forty‐two adult foxes were live‐trapped during 3 years of field work. In contrast to red foxes studied in other areas, no strict territoriality was observed in this population. Although close interaction (separation < 1 m) was more common between members of the same, rather than different, social groups, medium distance interactions were similar. Further, intra‐group encounters were much less common than for foxes in the U.K., and foxes did not avoid each other at territory boundaries. All foxes used food‐rich sites associated with human activity, and aggregations of up to four foxes were regularly seen in these areas. It is suggested that the combination of an extremely harsh environment, with spatially and temporally variable food supplies, leads to the formation of loosely knit social groups. Saudi Arabian red foxes followed Bergmann's rule in being considerably smaller than those found in cooler areas. They also had a lighter coloured pelage than red foxes typical of Europe and North America. These morphological differences may represent adaptations to the low availability of food and rest sites in the desert.

Diet of Fishers (Martes pennanti) at the Southernmost Extent of Their Range

Fishers ( Martes pennanti ) in the mountains of California's Sierra Nevada occur at the southwestern margin of their distribution and inhabit different forest types with different potential prey than elsewhere in their range. Two typical fisher prey, the snowshoe hare ( Lepus americanus ) and the porcupine ( Erethizon dorsatum ), are absent from our Sierra Nevada study area. We characterized the diet of fishers in the southern Sierra Nevada by analyzing the content of 201 feces (44 males: 157 females) collected either from trapped animals or from the rest sites of radio-collared animals. Mammals were the most frequent food item; however, unlike previous reports, reptiles (20.4% of feces) and insects (55.7%) were major components of the diet. We also sampled 24 feces for the presence of spores of hypogeous fungi (false truffles) and found that 91.7% had spores representing at least six fungal species. Diversity of the diet was indicated by the fact that remains of no single family of animal or plant group were found in >22% of feces. The fisher is reputed to be a habitat specialist in the late-seral mixed conifer-deciduous forests of the western United States. Perhaps it is for this reason that our data depict the species as a dietary generalist, for whom it may be necessary to forage on many of the animal, plant, and fungal species that occur in and near mature coniferous habitat.

Female Coordination of Group Travel in Wild Propithecus and Eulemur

Coordination of primate group movements by individual group members is generally categorized as leadership behavior, which entails several steps: deciding where to move next, initiating travel, and leading a group between food, water sources, and rest sites. Presumably, leaders are able to influence their daily foraging efficiency and nutritional intake, which could influence an individual's feeding ecology and long-term reproductive success. Within anthropoid species, females lead group movements in most female-bonded groups, while males lead groups in most nonfemale-bonded groups. Group leadership has not been described for social prosimians, which are typically not female-bonded. We describe group movements in two nonfemale-bonded, lemurid species living in southeastern Madagascar, Propithecus diadema edwardsi and Eulemur fulvus rufus. Although several social lemurids exhibit female dominance, Eulemur fulvus rufus does not, and evidence for female dominance is equivocal in Propithecus diadema edwardsi. Given the ecological stresses that females face during reproduction, we predict that females in these two species will implement alternative behavioral strategies such as group leadership in conjunction with, or in the absence of, dominance interactions to improve access to food. We found that females in both species initiated and led group movements significantly more often than males did. In groups with multiple females, one female was primarily responsible for initiating and leading group movements. We conclude that female nutritional needs may determine ranging behavior to a large extent in these prosimian species, at least during months of gestation and lactation.

Impact of Predation Risk on the Behaviour of Propithecus Diadema Edwardsi in the Rain Forest of Madagascar

The main predators on large-bodied primates in rain forest are birds of prey and mammalian carnivores, which may require distinct strategies by prey for successful detection and defense. In the three dimensional rain forest environment with diminishing light at lower levels, downward visibility is difficult, and keen eyesight may not be as effective for detecting in-forest predators as soaring ones. It is therefore predicted that cryptic behaviours, where the problems of detection are shifted to the predator, may be used in these conditions. In Madagascar there is debate on whether extant eagles are a threat to the largest primate species, while there is mounting evidence that a mammalian carnivore, the fossa, impacts heavily on lemur populations. In a new approach to understanding the differential impact of raptor and carnivore hunting styles on lemur anti-predator behaviours, I analyzed ten years of behavioural data on Milne-Edwards' sifakas in the rain forest of Madagascar. I show that Propithecus diadema edwardsi responds to aerial predators by giving loud alarms calls with responsive avoidance behaviour, and by choosing daytime rest sites lower than feeding sites. In response to the mammal predator, Propithecus gave a distinct ground predator call, used higher nighttime sleep sites than daytime rest sites, and males were in most dangerous spatial positions during travel and feeding. The combination of protective travel order, high sleeping sites and small sleeping parties suggested behaviours against fossa predation. However, the dramatic 'alarm call and drop low in the canopy' response to birds of prey is an indication that avian predators are feared.

A Comparison of the diet and distribution of southern river otter (Lutra provocax) and mink (Mustela vison) in Southern Chile

In Chile, between latitudes 39d̀S and 43d̀30'S, southern river otter (Lutra provocax) and introduced mink (Mustela vison) scats were collected. Mink sign was recorded in 29% of the aquatic habitat where otter sign was found. Sixty‐eight per cent of mink scats were collected at otter rest sites. A significant difference between the diets and low percentage of habitat use overlap of the two species (5‐22%) suggest that, in Chile, river otter and mink coexist with little competition for space or food. There are no data supporting a relationship between the introduction of mink and the decline of southern river otters.

Use of Tree Cavities by Fox Squirrels and Raccoons in Indiana

We investigated interspecific relationships between fox squirrels ( Sciurus niger ) and raccoons ( Procyon lotor ) through a comparison of use of dens in winter at Muscatatuck National Wildlife Refuge in southcentral Indiana, January–March 1984–1985. Fox squirrels selected dens with smaller entrances and volumes; dens of squirrels were located greater distances from water than cavities used by raccoons and unused cavities. Dens occupied by fox squirrels had smaller entrances and shorter distances to forest openings than cavities previously used by fox squirrels, but unoccupied when examined. Den sites of raccoons did not appear to be a limiting resource in winter because of a large number of unused cavities. Raccoons were not important competitors for cavities used by fox squirrels, but squirrels selected maternal or rest sites that could restrict vulnerability to predation by raccoons by limiting access to cavities. Selection of den sites relative to thermoregulatory costs also could influence choice of dens by fox squirrels.

Habitat richness affects home range size in the red fox Vulpes vulpes

The spatial behaviour of the red fox Vulpes vulpes shows a great flexibility (Voigt and Macdonald, 1984). Home range size varies from 10 to over 5000 ha (Macdonald, 1987; Voigt, 1987). In carnivores, variations in home range size, weighed for body mass (Gittleman and Harvey, 1982), are largely related to differences in habitat productivity, but the intraspecific local variation in home range size can be only partially explained by differences in productivity. Macdonald (1981, 1983) suggested that home range size and configuration were determined in the red fox by the dispersion of food-rich patches. More recently, it has been found that 1. (a) where humans are intolerant to the fox, resting sites are often located peripherally in home ranges (Meia and Weber, 1993); 2. (b) the ranging behaviour of red foxes cannot be explained only by the features of food resources in a complex environment with several productive habitats (Cavallini and Lovari, 1994); and 3. (c) home range size may be directly related to the distance between rest sites and food patches (Lucherini et al., in press). In this paper, evidence for a strong influence of habitat richness on home range size of the red fox is reported.

Movement Patterns of Mountain Lions during Different Behaviors

We used radiotracking and other observations to describe nocturnal movement patterns of mountain lions (Felis concolor) during six different behaviors and attempted to estimate behavior rates by inference from such patterns. When hunting, mountain lions apparently stalked or sat in ambush for periods averaging 0.7 h and then moved a mean distance of 1.4 km (over 1.2 h) to another area; this pattern repeated about six times on nights when no prey was killed. When a mammal was killed, this pattern was suspended until the carcass was consumed (4–6 h for a small mammal, 2–5 days for a large mammal). When feeding on a large mammal, mountain lions minimized spoilage and loss to scavengers by dragging the kill 0–80 m to a cache site, burying the carcass under leaves and debris during the daytime, and feeding only at night. Mountain lions increased the risk of loss to scavengers by locating diurnal rest sites up to 4.2 km (X̄ = 400 m, SD = 787) from the carcass. Mating associations lasted 2–5 days, during which mountain lions traveled little, vocalized frequently, and apparently did not feed. Mothers of neonates hunted from dusk to midnight and then returned to the den; mothers spent increasing amounts of time at greater distances from the den during the first 8 weeks after giving birth. Dens were located in nearly impenetrable vegetation and den sites lacked feces, prey remains, or modifications of the site. On average, an adult mountain lion killed ca. 48 large and 58 small mammals/year and fed for an average of 2.9 days (SD = 1.1) on a single large mammal. Although movement patterns differed markedly among behaviors, discriminant functions failed to accurately predict behavior from movement patterns.

Size-Related Functional and Energetic Constraints in the Foraging of the Limpet Patella vulgata (Mollusca, Gastropoda)

1. The effect of size-related functional and energetic constraints (respiration, production of mucus, ingestion rate) on the foraging behaviour of a population of the limpet Patella vulgata L., inhabiting a sheltered shore at Menai Bridge (Anglesey, UK), was examined. 2. The minimum acceptable energy content per unit area (u min ) that an algal pasture should have to be profitably exploited by a limpet of a given size was first determined. 3. Second each excursion was modelled as being made up by a linear sequence of discrete spatial locations, whose energy content per unit area (u i ) linearly increased with the distance from the limpet's rest site. Each limpet was assumed to select suitable foraging sites by adopting a simple 'all-or-nothing' rule : to exploit completely a given location if u i ≥u min or, if u i < u min , to skip to the next one. 4. The model foresees that specimens which select sites on this basis will have a greater net rate of energy intake than limpets exploiting all the locations. Moreover, among the selective limpets, larger specimens will have a lower net rate of energy intake over the whole excursion than smaller ones, if they cover the same number of locations. In addition, larger limpets should concentrate their foraging more around the point of maximum distance, than smaller ones. 5. Although including a minimum set of simple assumptions the model is able to reproduce the effects of size-related constraints on the behaviour of limpets in this population. In particular, the predicted difference in the spatial organization of foraging between different size classes agrees with the results of field observations.

Observations on the predation behaviour of the otter Lutra lutra in NE Spain

Adult and sub-adult otters Lutra lutra (Linnaeus, 1758) caugh and consumed 3.36 prey (fish) per hour (n=32 captures). This represents 273.8 g of wet mass/h of activity outside the rest sites. (10.5-13.1% of the day) and it is enough to get their daily needs. Otters ate the pray without hiding on average (n=93) 0.46 m from the bank (up to 3.9 m) and 0.25 m above water level (up to 2.05 m). Prey weighing less than 150-200 g were consumed entirely, for this reason prey remains are very rare (except large trout, American crayfish and gravide cyprond females). Unpleasant tasting or toxic parts and sharp or wide parts of the bones, scales, teeth, claws, heads or leggs in large prey were not eaten.

Influence of season, sex, and site availability on fisher (Martes pennanti) rest-site selection in the central hardwood forest

We monitored 20 adult fishers (8 males, 12 females) to investigate the effects of season, sex, and site availability on rest-site selection by fishers at the southern extent of their range. Data on rest-site locations (n = 219) and random sites (n = 194) were collected from December 1989 through February 1991. Fishers rested in hardwood, softwood, and mixedwood forest types in proportion to their availability in summer; however, hardwoods were used less than expected in winter. Fishers used nests, cavities, and burrows in proportion to their availability in winter. In summer, however, nests were selected twice as often as expected, cavities were used less than expected, and burrows were not used. Male fishers tended to use larger cavity trees and mixed forest stands more often than females did. In winter, fishers were not restricted to coniferous forest types, as occurs at the northern extent of their range, because moderate snow depths did not restrict movement and prey may have been more available in other forest types. Fishers appeared to select rest-site types most suitable for thermoregulation and obtaining prey. Trees with diameter at breast height ≥ 32 cm may provide cavities for rest sites in hardwood-dominated forests.

Effects of Scale on Habitat Selection and Foraging Behavior of Fishers in Winter

Several researchers reported that fishers ( Martes pennanti ) select lowland-conifer habitats, where snowshoe hares ( Lepus americanus ) are abundant, for foraging and resting and therefore, avoid open, upland-hardwood habitats. In the Ottawa National Forest, Upper Peninsula, Michigan, in the 1970s, porcupines ( Erethizon dorsatum ) occurred in open, upland-hardwood habitat that provided fishers with more than on-half of their energy requirements. If fishers select habitat on the basis of location of important prey, they should hunt disproportionately in hardwood habitat. Fishers, however, appeared to recall locations of porcupine dens in winter and traveled directly to dens, thereby minimizing distance traveled in habitat of porcupines. I hypothesized that fishers would avoid upland-hardwood habitat, despite availability of porcupines, because foraging for porcupines is efficient. Tracks of fishers were followed and mapped. Distribution of habitats available near tracks and available in the study area were quantified using random transects on maps of habitat types. Fishers selected habitats on at least two different scales. On the coarser scale, fishers foraged in areas with greater availability of pine habitat and lowland conifers and less upland hardwoods than was available over the entire study area. On a finer scale, within the vicinity where fishers foraged, they selected lowland-conifer forest and avoided open areas, northern-hardwood, aspen-birch and hemlock forests. Fishers selected dense, lowland forests and avoided northern hardwoods for rest sites; selection of habitats for rest sites was stronger than for travel, making this a possible third scale of selection.