Habitat Selection

An individual-based model of nesting smallmouth bass, Micropterus dolomieu, is used to predict the effects of water level fluctuations on reproductive success. The model simulates daily nest site selection, spawning, nest guarding, and development and survival of eggs, embryos, and larvae until dispersal. The model was configured for Brownlee Reservoir, Idaho-Oregon. Each reservoir bank is represented as a rectangular grid of cells, with each cell characterized by an assigned slope, substrate, and elevation, and by a water depth that varied daily. Nest site (cell) selection is determined from a habitat suitability index (HSI) based on substrate, slope, and depth. Development of young is temperature-dependent. Mortality of young occurs via attrition, abandonment by the guarding male, and probabilistic whole-nest catastrophe. Simulations were performed that used observed data for 1991 to 1996. Model predicted nest habitat selection and egg-to-dispersal survival rates were similar to observed values. Additional model simulations showed that: (1) nest habitat selection was best predicted when depth, slope, and substrate were considered together rather than singly, (2) egg-todispersal survival was related to the magnitude of water level fluctuations during the peak spawning period, (3) relating mortality to HSI values resulted in lower survival, while relating growth to HSI values resulted in higher survival, and (4) spawning habitat is not limiting in Brownlee Reservoir. Suggestions for future monitoring of reservoir-based smallmouth bass populations are discussed.

Estuarine fishes are generally much more abundant in structurally-complex seagrass beds than in nearby sand flats. We tested for this pattern by comparing trawl catches from adjacent seagrass beds and sand flats within Turkey Point Shoal, a shallow estuarine system in the northern Gulf of Mexico. Fish abundance in seagrass beds (primarily Thalassia testudinum Konig) was slgnificantly (760%) higher than in sand flats. Pinfish Lagodon rhomboides (Linnaeus) accounted for much of this difference. Laboratory experiments in behavioral arenas were performed to determine whether this difference was due to habitat selection. In the absence of predators, pmfish used seagrass and sand equally. Additionally, groups of pinfish swam about freely within the water column. Therefore, habitat preference alone does not likely explain the patterns observed in the field. We then tested the hypothesis that observed habitat use patterns were due in part to predator-mediated habitat selection. Pinfish tended to avoid non-vegetated sections of behavioral arenas after predatory southern flounder Parulichrhys lerhostigma Jordan and Gilbert were introduced. Qualitative observations indicated that pinfish also reduced their use of the upper water column in the presence of these predators. Therefore, behaviorally mediated predator avoidance may help explain observed patterns of differential habitat use within estuarine mosaics of sand and seagrass habitats.

During 1997–1999, 32 Woodland Caribou (Rangifer tarandus caribou) were translocated from the Sustut Herd to the Telkwa Mountains in westcentral British Columbia to augment recovery of the Telkwa Caribou Herd. The animals were fitted with radiocollars and located during 1997–2000 to determine selection of habitat features and terrain variables. Six Caribou calves were also collared to determine causes and timing of calf mortality during summer 1999. Defining available habitat for newly translocated animals is often arbitrary and subjective, and we based the analyses on ranks for habitat use and availability as this is less sensitive to the inclusion or exclusion of a questionable resource. This method represents some loss of information but provides indications of the relative importance of various habitat types without classifying any as avoided. High elevation habitat (> 1700 masl) on moderate slopes (16 – 45°) received the highest ranks, as did “warm” (136 – 315°) aspects and f...

Although stony corals are most frequently studied on high-relief reef structures, many coral species occur in a wide variety of nearshore tropical habitats, including mangrove creeks, seagrass beds and rocky platforms. This study estimated overall population size, potential reproductive output, and population structure for several species across sandy-bottom, hard-bottom, and patch reef habitats. The density of coral colonies, area of available habitat, and size distribution of resident Siderastrea radians, Favia fragum, and Diploria clivosa colonies were recorded for several island bank systems across habitat types in the central Bahamas. Nearshore patch reefs generally exhibited larger population sizes and higher density of colonies, and contained more larger or older colonies. Nearshore hardbar communities had smaller population sizes and a lower density of colonies, and supported more small colonies, which may either be recruits or asexual clones. High numbers of larger colony s...

Conservation of fauna breeding in vernal pools is challenging given their complex life histories. Many species, including the widespread North American Wood Frog (Rana sylvatica), require both aquatic and terrestrial habitat, yet insufficient information exists about movements between these environments, nor fine-scale selection patterns within them. To inform conservation planning, we conducted a radio-telemetry study of seasonal patterns of Wood Frog movements and habitat selection in southern Maine. Forty-three frogs were tracked an average of 25.6 days each, April to November 2003. In early spring, Wood Frogs generally selected damp leaf litter retreats on the margins of breeding pools. Following breeding, frogs selected forested wetlands (9.3% of the landscape) over forested uplands (90.7% of the landscape) in 75.3% of radio locations (N 5 544). Postbreeding movements from breeding pools to nearby, closed-canopy, forested wetlands ranged from 102-340 m (median 169m, N 5 8) and included stopovers in upland forest floors ranging from one to 17 days (median two days, N 5 7). Summer refugia were characterized by shady, moist (nonaquatic), and sphagnum-dominated microhabitats. In urbanizing areas, we recommend a shift from a core-habitat conservation model to a spatially explicit approach that considers pool-breeding amphibian habitat as a network of migration-connected habitat elements (e.g., breeding pools, upland forest, nearby forested wetlands). In our study, this approach reduced the amount of land potentially requiring protection by . 2/3 from that of core habitat models. With the rapid dissemination of GIS technology, spatially explicit planning for pool-breeding amphibians is increasingly feasible.

Ontogenetic shifts at lizards' microhabitat selection were studied using sand lizard (Lacerta agilis) as model organism. Field observations evidenced that sightings of hatchling lizards followed the distribution of microhabitat categories while yearlings and adults showed a more active perch selection. However, multivariate analysis evidenced active selection at all age categories. Genuine ontogenetic shifts in habitat selection were recorded with most outstanding differences between hatchlings and yearlings. Lizards' perching sites were significantly more homogenous than randomly selected control spots. Microhabitat characteristics measured at adults and yearlings were similar and differed significantly from those measured in the case of hatchlings. Multivariate analyses offered more detailed picture about lizards habitat use and proved to be more sensitive than the traditional goodness-of-fit tests.

Extensive logging of the boreal forest rejuvenates landscapes once dominated by old-growth stands. As black bear ( Ursus americanus Pallas, 1780) fitness and behavior are known to be primarily related to the abundance of shade-intolerant soft mast species in northern forests, we hypothesized that logging will influence habitat and space use patterns of black bears. We used VHF telemetry on 12 female black bears in the Réserve faunique des Laurentides (Quebec, Canada) to investigate seasonal patterns of habitat selection in an exploited heterogeneous boreal landscape at different spatial scales. Habitat characterization based on seven forest cover types allowed us to compare the productivity of key forage species in various post-logging age classes. Regenerating stands (6–20 years old) had the uppermost ground vegetation cover, providing both the highest density and a high biomass of berries. Black bears preferred regenerating stands (6–20 years old) and avoided mature coniferous for...

The little bustard Tetrax tetrax is a threatened grassland bird highly reliant on agro-ecosystems for survival. Understanding its habitat requirements throughout its yearly cycle is essential to promoting adequate management practices. A late summer, post-breeding habitat selection study was conducted at three sites located in Alentejo, in the south of Portugal. Overall, 48 flocks were counted. A highly-significant explanatory logistic model demonstrated that little bustard post-breeding sightings primarily occur in locations with greater food availability, adequate vegetation height, and more productive soils. Fallow land and areas grazed by sheep tend to be avoided. Additionally, the species abundance was estimated at 18 sites distributed among the specie's main range in Portugal, covering 67,000 ha and 971 km of car transects. Another 119 flocks were registered. Surprisingly, hardly any birds were found at priority breeding sites. Overall, the data suggest that important breeding populations of the little bustard dependent upon extensive agriculture within Iberia (generally where soils are less productive), are likely to depend on other areas with greater food availability during the dry summer season. Maintaining suitability of the habitat near important breeding areas with more productive soils could prevent further species movement in search of foraging areas and diminish mortality risk. At these sites, conservation efforts should focus on maintaining the landscape open and ensure the dominance of low intensity land uses with short vegetation, such as cereal stubbles or certain legume crops.

Habitat selection by female Dall's sheep (Ovis dalli dalli) during lambing was studied in interior Alaska, U.S. A., in 1988 and 1989. Selection of habitat changed with the chronology of lambing. During the prelambing period, maternal females selected sites with forage and avoided snow-covered areas. During peak lambing, food and steep slopes continued to be selected. Distance to escape terrain was a critical component of habitat selection by females throughout lambing. Maternal bands that ventured farther from escape terrain were in larger groups. Abundance of forage also increased in areas that were farther from this terrain. Habitat selection by females also differed between years. In 1989, a late spring storm resulted in deep snow and delayed phenology of plants; forage was of lower quality, and the growing season was much shorter in 1989 than in 1988. Births of lambs also occurred later and less synchronously in the second year. Females selected terrain characteristics that were related to avoiding predators in 1988 when forage was more plentiful, but selected sites with forage in 1989 when food was less abundant. Group size of maternal bands was larger in 1988 than in 1989, and females foraged most ef®ciently during 1988. Large groups may not have occurred in 1989 because lambs were born asynchronously, preventing cohesive movements of maternal bands with lambs of differing ages. Both the chronology of lambing and a variable environment affected habitat selection by females. Maternal females made trade-offs between the requirements for forage to meet the high energetic costs of lactation and the risk of predation.

Habitat use of breeding diving ducks is not well-documented. I studied nesting and brood-rearing female redheads (Aythya americana) in southwestern Manitoba during 1994 and 1995 to document habitat use and associations between wetland characteristics and reproductive success. Most females nested in small, semi-permanent wetlands and were successful in wetlands with large bands of emergent cover. Success was associated with water depth at the nest and distance between the nest and dry land. Brood-rearing females switched from smaller wetlands used for nesting to larger, semi-permanent wetlands. Successful females selected appropriate habitat whereas unsuccessful females showed no preferences. These results support a landscape approach to wetland management and emphasize the need for plans that reduce impact to wetland margins.

Habitat quality, and the levels of habitat variables that are associated with good habitat, can vary between years. Therefore, animals that are able to adjust their habitat selectivity should enjoy higher fitness. I examined the use of experience in habitat selection during natal dispersal in Hemilepistus reaumuri, a monogamous, semelparous desert isopod. Young from the previous year emerge in the spring and walk from a few to over one thousand metres before establishing burrows or settling in already established burrows. Isopods were held in outdoor pens for 7-day priming treatments, then moved to new pens and tested for settling 4 days later. Perceived habitat quality was defined as the fraction of isopods settling in each pen during its use in the 7-day priming treatments. Settling was tested as a function of the change in perceived quality isopods experienced. Settling was significantly positively correlated with change in perceived quality, suggesting that experience is used to prime habitat selection during dispersal, and that the effects of experience last at least a few days in desert isopods. Time of year also had a significant positive effect on settling. The effect of change in perceived quality was stronger than the effect of perceived quality in the final pen. If changes in habitat are used to calibrate settling decisions, longer dispersal distances may be needed to allow for habitats to be compared. Use of experience to regulate settling may also affect the population dispersal response to habitat change.

Terrain ruggedness is often an important variable in wildlife habitat models. Most methods used to quantify ruggedness are indices derived from measures of slope and, as a result, are strongly correlated with slope. Using a Geographic Information System, we developed a vector ruggedness measure (VRM) of terrain based on a geomorphological method for measuring vector dispersion that is less correlated with slope. We examined the relationship of VRM to slope and to 2 commonly used indices of ruggedness in 3 physiographically different mountain ranges within the Mojave Desert of the southwestern United States. We used VRM, slope, distance to water, and springtime bighorn sheep (Ovis canadensis nelsoni) adult female locations to model sheep habitat in the 3 ranges. Using logistic regression, we determined that the importance of ruggedness in habitat selection remained consistent across mountain ranges, whereas the relative importance of slope varied according to the characteristic physiography of each range. Our results indicate that the VRM quantifies local variation in terrain more independently of slope than other methods tested, and that VRM and slope distinguish 2 different components of bighorn sheep habitat.

Habitat use and selection of 14 Alpine ibex males were studied in the Gran Paradiso National Park. Alpine meadows were always overused and positively selected, because this habitat constituted an important food resource for the ibex. Even if rocks(30%) and stone ravines(22%) were ...

The dietary structure and distribution patterns of red foxes Vulpes vulpes in situations of different food supply in the coniferous-deciduous (mostly small-leaved) woodlands of northern Belarus were investigated. A total of 1526 scats of red foxes was analysed, and snowtracking of the species was performed each winter. Abundance of the main prey (small rodents, perching birds and hares) and wild ungulates supplying carrion for red foxes in the cold season were monitored. The results suggest that in northern Belarus red foxes had a diversified diet, consisting basically of different combinations of bank voles, Microtus voles, and wild ungulate carrion. The importance of carrion much increased in winter, while the proportions of birds and fruits grew during the warm season. In the ecologically rich woodland harbouring on clay soil, red foxes relied more on small rodents, while carrion and fruits appeared to be more important food item of the predator in the barren forested terrain dwelling on poor sandy deposits. During Microtus population outbreaks, red foxes more frequently fed on this prey. One-sixth lower density of red foxes was attributable to the forested terrain on sandy deposits compared to the woodland on clay soil, and a pronounced landscaperelated difference in the habitat selection by the predator was found.

Yellowstone have further bolstered the regional population. However, rigorous analysis of either the availability of wolf habitat in the entire region, or the specific habitat requirements of local wolves, has yet to be conducted. We examined wolf-habitat relationships in the northern Rocky Mountains of the U.S. by relating landscape/habitat features found within wolf pack home ranges (n ¼ 56) to those found in adjacent nonoccupied areas (n ¼ 56). Logistic regression revealed that increased forest cover, lower human population density, higher elk density, and lower sheep density were the primary factors related to wolf occupation. Similar factors promoted wolf pack persistence. Further, our analysis indicated that relatively large tracts of suitable habitat remain unoccupied in the Rocky Mountains, suggesting that wolf populations likely will continue to increase in the region. Analysis of the habitat linkage between the 3 main wolf recovery areas indicates that populations in central Idaho and northwest Montana have higher connectivity than either of the 2 recovery areas to the Greater Yellowstone recovery area. Thus, for the northern Rocky Mountains to function as a metapopulation for wolves, it will be necessary that dispersal corridors to the Yellowstone ecosystem be established and conserved.

We studied habitat selection by Rhinolophus euryale in a rural area of southern Italy in 1998-2000 by radio-tracking. Two comparisons were carried out, one between habitat occurrence within individual home ranges and within the study area, the other between time spent in each foraging habitat and habitat occurrence within the home range. The first analysis showed that olive groves and conifer plantations were, respectively, the most and the least important habitats. The second analysis highlighted the importance of woodland for R. euryale, while urban sites, open areas and conifer plantations were avoided. We recommend that clearing of continuous, large areas of woodland for tree harvesting should be avoided. Conifers should not be used for reforestation. Urbanisation should be limited in the areas of greatest importance for the species, and linear landscape elements such as tree lines and hedgerows should be maintained. #

Telemetry A B S T R A C T Leopards (Panthera pardus) are endangered in South East Asia yet little is known about which resources need to be secured for their long-term conservation or what numbers of this species this region can support. This study uses radio telemetry to investigate seasonal variation in habitat selection and home range size of Leopards in Huai Kha Khaeng Wildlife Sanctuary, Thailand. Over a five year period, 3690 locations were recorded from nine individuals. The mean ± standard error of fixed kernel home range size for six adult females was 26 ± 8.2 km 2 , for two adult males was 45.7 ± 14.8 and for two sub-adult females was 29 km 2 ± 5.5. Adult female wet and dry season home range sizes did not differ significantly.

A study of the Japanese badger Meles meles anakuma was undertaken in Hinode, a suburb of Tokyo, between 1992 and 1998. Faecal analysis, based on 82 samples, revealed that during spring and summer, earthworms (Megaseolocidae spp.) occurred at high frequency in the diet, with berries (Rubus spp.), beetles and persimmon Dymopyrus kaki also eaten during summer months. Scavenged food was eaten in early spring when earthworm availability was low, and badgers switched from worms when persimmon became abundant in autumn. Twenty-one Japanese badgers (14 males and seven females) were radio-tracked. Adult badger home ranges were stable, and those of males [40 AE 19 (SD) ha, n = 7] were larger than those of females [11 AE 6 (SD) ha, n = 4]. Badger resting sites in each home range were located within 630 m of each other and categorized as setts or couches. Setts were sited within core areas (30% adaptive kernel method ) of home ranges. Most setts were on a sub-ridge and avoided west-facing slopes. Couches, mainly in deciduous forest and forest edge, were generally sited towards the periphery of home ranges. Most badger foods were distributed along ecotones between forestry plantations and farmland; earthworms, their main food from late spring to summer, and berry thickets were both concentrated at the edge of conifer plantations. Persimmon trees, the main food source for badgers in autumn, were also found in agricultural land bordering forest edge. Badger home range size was related to forest edge density.

At high latitudes and altitudes, ice formation is a major variable affecting survival of freshwater fauna and hence the abundance and composition of invertebrate communities. Freezing, but also desiccation and anoxia, are lethal threats to all life stages of aquatic insects, from the eggs to the adults. During cold periods, the aquatic stages commonly remain in or move to a

African elephants can affect the quality of the habitat of other species by breaking or uprooting trees and shrubs in savannas. Their effect on vegetation has been widely studied but less is known about the effects of such vegetation changes on other animals. We studied how changes in the vegetation caused by elephants influence the selection of microhabitats by five African herbivore species (giraffe, kudu, steenbok, impala, and zebra) in Hwange National Park, Zimbabwe. There was no clear significant effect of overall elephant-induced vegetation changes on microhabitat selection except for the small species (steenbok and impala) that used vegetation modified by elephants preferentially. This is consistent with a medium-term browsing facilitation hypothesis. More subtle possible effects were detected for larger browsers (giraffe and kudu). They selected areas with broken and uprooted plants and avoided coppiced areas. All of the browsers selected sites characterized by plants uprooted and broken by elephants, which were associated with a higher visibility, and ultimately a better probability of detecting an approaching predator, suggesting that perceived predation risk plays an important role in microhabitat selection. These results illustrate how elephants can initiate indirect effects that influence microhabitat selection by other herbivores. Understanding the indirect effects of elephants through changes in food availability and predation risk thus needs further investigation. The results of this study do not provide support for the hypothesis that elephant-induced changes in the structure of habitats have caused the declines in the populations of the other herbivores in the study area.

This study investigated the anti-predator strategies adopted by 19 radio-collared female roe deer during the fawning season by monitoring their spatial behaviour and habitat selection by means of radio-tracking. The study was carried out in a forest area of the Apennine Mountains (central Italy), where wolves are natural predators of roe deer and in summer fawns are more frequently predated than adult roe deer. The presence of fawns was monitored by means of direct observations. Roe deer fawns are known to adopt the hiding strategy during the lactation period, when they lie concealed for long periods waiting for their mothers' milk. As a consequence of this, the home-range sizes of mothers were significantly smaller than those of non-mothers during the summer lactation only. In contrast, no significant difference was found in spring, when fawns were absent, or autumn, when they were already weaned. In order to increase the success of the hiding strategy adopted by their fawns ag...

Previous studies have proposed that seagrass habitats, by supporting diverse and abundant fish assemblages, are preferred by foraging dolphins in coastal systems. To test this hypothesis, we (1) examined the fine-scale behavior of bottlenose dolphins in relatively pristine and developed inshore sites near Clearwater Harbor, Florida, USA, and (2) used an otter trawl to sample potential fish prey in non-seagrass and seagrass habitats. In the pristine site, dolphins preferred dredged channel and spoil-island habitats, while least preferring shallow seagrass habitats. In the developed site, foraging dolphins preferred the natural channel habitat, but exhibited little further selection. Therefore, the hypothesis that dolphins prefer seagrass habitats while foraging was rejected. Feeding frequency was significantly associated with diel state, with foraging peaking at dawn and decreasing throughout the day. Dolphin group size was negatively correlated and nearest neighbor distance positively correlated with feeding frequency. Analysis of trawl data focused on the pinfish Lagodon rhomboides which dominates the diets of dolphins in west Florida. The relative abundance of pinfish was significantly greater and standard lengths significantly less in seagrass than in non-seagrass habitats. Dolphins therefore forage in non-seagrass habitats where fish prey is both larger and perhaps more available. Although seagrass habitats support greater abundance of smaller fishes, they also provide a structural refuge which obscures fishes both visually and possibly acoustically. Thus, the importance of seagrasses to the health of coastal dolphins is probably indirect, as seagrasses support fish populations on which dolphins rely.

RESUMEN
El Cocodrilo Americano es una especie clave en el mantenimiento y función de los ecosistemas costeros a largo plazo por las actividades que realiza, sin embargo está catalogado como en amenaza de peligro de extinción (EN) UICN, por otro lado existe un escaso conocimiento sobre la biología e historia natural de esta especie en la Isla de Coiba. El presente estudio determinó la ecología espacial de Crocodylus acutus en el Parque Nacional Coiba (PNC), Panamá, durante el periodo febrero - julio del 2013, usando radio-telemetría UHF y estimadores de Home range. Se realizaron 75 monitoreos a lo largo de los circuitos a 21 individuos (con longitud total promedio = 137.90 ± 55.64 cm), registrando 309 ubicaciones geoespaciadas, con un promedio de localización de 14.76 ± 9.91 puntos por individuo. El análisis de centros de actividad o Densidad de Kernel (KD) en el área de estudio tuvo un valor de 49.90% de probabilidades máximas de encontrar un ejemplar, sobre el área de actividad que adquirió 10.29 km2 de Mínimo Polígono Convexo (MPC) 100%. El Cocodrilo Americano presentó desplazamientos principalmente por el medio marino, siendo de 5.61 km la distancia máxima recorrida por un individuo de talla adulta. En cuanto a la selección de hábitat, no hay duda que los manglares son los hábitats por excelencia con un 58% de los puntos ubicados allí. La selección de hábitat va a depender de la longitud total del individuo, con reportes de subadultos con más incursiones hacia el mar, mientras que los juveniles estuvieron en zonas someras; como también dependen del periodo climático, ya que en la época lluviosa aprovecha los manglares inundables con conexiones hacía varias redes hídricas dulceacuícolas. Sin embargo, en este estudio las diferentes horas del día y las distintas fases de la luna no dependieron para la selección del hábitat de esta especie, sugiriendo que el factor que influye principalmente en la selección de hábitat podría ser la temperatura. La presencia de esta especie a lo largo del estudio, da indicios que está en un sistema de alto nivel de conservación influenciado por la baja presión humana en esta isla, siendo considerados indicadores de salud de los ecosistemas del PNC, que en un momento de su historia tuvo efectos negativos por factores antropogénicos.

ABSTRACT
The American crocodile is a key species in the maintenance and function of coastal ecosystems in the long term by its activities however is listed as a threat to endangered (EN) IUCN, also has a poor knowledge about the biology and natural history of the American crocodile in the island of Coiba. The present study determined the spatial ecology of Crocodylus acutus in Coiba National Park (CNP), Panama, during the period from February to July 2013, using UHF radio-telemetry and home range estimators. 75 samplings was performed in the different circuits to 21 individuals captured (with the average total length = 137.90 ± 55.64 cm), recording 309 geospatial locations, with an average of localization 14.76 ± 9.91 points per individual. The analysis of the activity area for this specie had a value of 10.29 km2 MPC (100%), with activity centers (KD) in the study area is 49.90% of maximum probabilities of finding an exemplary C. acutus. The American crocodile presented displacements mainly the marine environment, being 5.61km maximum distance traveled by an individual adult size. As for the habitat selection, of C. acutus, there is no doubt that mangroves are the quintessential habitats with 58 % of the points located there. Habitat selection will depend on the total length of the individual, with reports of subadult more incursions into the sea, while juveniles were in shallow areas, and also depend on the climatic period, because in the rainy season C. acutus used flooded mangroves with several network connections freshwater. However in this study, the different hours of day and different phases of the moon didn’t depend for habitat selection of this specie, suggesting that the factor that mainly influences habitat selection could be the temperature. The presence of this specie along the study gives evidence that system is in a high level of conservation, influenced by low human pressure on this island, being considered as indicators of ecosystem health of the CNP that in a time of history had negative effects by anthropogenic factors.

The giant molerat Tachyoryctes macrocephalus is a high-altitude specialist endemic to the Bale Mountains, Ethiopia, and an important prey species for the endangered Ethiopian wolf Canis simensis. We assessed molerat prevalence, habitat preferences and availability to wolves, using direct observation and transect sampling for field signs. Mean densities of molerats ranged from 17/ha to 40/ha, and they were most prevalent

The origins, early history, captive populations, spread and habitat preferences of Reeves' Muntjac in Britain are reviewed. It is suggested that much of the published information on the history of Muntjac in Britain is based on misconceptions, and that each subsequent report has continued to promulgate a false impression on the origins, time-scale and pattern of spread of the species in Britain. Indian and Reeves' Muntjac were introduced to Woburn Park in Bedfordshire within a year of each other, and it appears that the Indian Muntjac did not thrive, at least in the decade following their introduction. How long they survived as a free-living species in Britain is unclear, but it was probably only a few years. However, there is some evidence to suggest that they might have persisted within the Park at Woburn until 1930.

Hundreds of thousands of giant snakes (Python reticulatus) are taken from the wild to be killed for their skins each year, raising doubts about the longterm sustainability of this otake. We visited four locations in northern Sumatra (Medan, Seisuka, Rantauprapat and Cikampak) at four times of year and gathered information on the sizes, sexes, reproductive status and food habits of 784 slaughtered pythons. Pythons in northern Sumatra mature at larger body sizes than do those studied previously in southern Sumatra (Palembang). Their seasonal timing of reproduction is shifted appreciably, presumably because the two areas lie on opposite sides of the equator. The slaughtered animals are mainly adult males and adult plus juvenile females. Females attain larger sizes than males, but very large females are rarely captured. This bias may re¯ect size-related shifts in habitat selection; smaller snakes (including adult males of all sizes, and recently-matured females) feed primarily on commensal rats and hence are abundant in disturbed (agricultural and village) habitats. Female pythons produce large clutches (mean=24.2) of large eggs (mass>250 g), but reproduce only once every 2 to 4 years. The apparent ability of reticulated python populations to withstand high levels of otake may re¯ect their demography (rapid growth rates, early maturation, high fecundity), their¯exibility in diets and habitat use, and their ability to evade detection (because neither foraging nor thermoregulation require extensive movements). #

We analyzed satellite track data for 186 loggerhead sea turtles in the North Pacific Ocean using remotely sensed environmental data to characterize pelagic habitat. A large number of candidate habitat variables were merged to the satellite track data and statistically compared to background values over a large spatiotemporal grid which bounded overall occupancy. Five statistically significant variables were identified out of the 16 environmental variables examined. Two of these variables have strong seasonal, interannual, and spatial patterns (sea surface temperature and chlorophyll a concentration), while three others were primarily spatial (earth magnetic force, earth magnetic declination, and earth magnetic inclination). Habitat selectivity for these variables was quantified using preference curve methodology established in the foraging literature. The output from the selectivity curves was used to predict a multivariate loggerhead sea turtle habitat index across the pelagic North Pacific. This predicted habitat was ground-truthed with newly available satellite track data.

In northern Europe at least, extensive knowledge of the systematics and ecology of spiders leads the authors to consider them as a very suitable group for pest limitation and for biodiagnostic purposes. An examination of both the qualitative and quantitative aspects of perdition by spider populations and communities is discussed as well as the evolution of some human factors occurring in agroecosystems that are likely to induce changes in spider predation such as chemical spraying and cultural practices. Studies addressing the recolonisation of agroecosystems by spiders, taking into account their dispersing abilities and habitat selection are summarised, followed by a discussion of the global efficiency of spiders as predators in such environments, the risks associated with their use and how to maximise their efficiency.

The house crow (Corvus splendens) has reached pest proportions in Singapore and requires an integrated system of population control measures. One such crucial component, possibly reducing its breeding success, was the focus of our study. We compared the nest sites (n 30) of the house crow with randomly selected sites (n 30) to determine which environmental variables, if any, are indicative of preferred nest sites. The chi-squared test revealed the yellow¯ame tree (Peltophorum pterocarpum) to be the preferred tree species used for nesting. We formulated our model based on 11 preselected variables using binary logistic regression and evaluated the strength of support for each model (relative to all other models) using the second order model selection criterion AIC c . The results indicate that house crows selected nests in areas that were more urbanised and open, with higher disturbance, nearer bin centres and food centres, and nested in trees that had larger crown volume, density and diameter. Based on these results, we suggest that urban managers can alter the landscape characteristics to make them less conducive for nesting crows. Such measures might include minor adjustments to the design of existing bin centres to prevent crows from entering, planting alternative, less suitable tree species in future, and regular pruning of trees with larger and denser crowns. #

Shorebirds, or waders, form an ecologically (but not phylogenetically) homogenous group of birds that, despite this homogeneity, exhibits clear correlated contrasts in habitat use and migration distance between closely related species pairs. In addition, within species there is distinct variation in breeding and wintering latitudes, i.e. migration distance. I examine here such contrasts at different taxonomic levels and evaluate what we can learn about selective forces on habitat selection and the evolution of migration strategies in birds. My primary example is the worldwide migration system of the Red Knot Calidris canutus. These sandpipers breed only on high arctic tundra (65-83°N), but they move south from their disjunct, circumpolar breeding areas to nonbreeding sites on the coasts of all continents (except Antarctica), between latitudes 58°N and 53°S. Due to their specialized sensory capabilities, Red Knots generally eat hard-shelled prey found on intertidal, mostly soft, substrates. As a consequence, ecologically suitable coastal sites are few and far between, so they must routinely undertake flights of many thousands of kilometres. In contrast to prediction, Red Knots at tropical intertidal sites have lower fuelling rates than birds at more southern or northern latitudes. This leads to greater time-stress in the southernmost wintering populations that not only have to cover over 14,000 km in single migrations, but also cannot rely on tropical regions to make refuelling stops. Rapid human-caused losses of the food-base in staging areas during both north-and southward migrations have been demonstrated to have caused rapid declines in several Red Knot populations. Detailed worldwide ecodemographic research on these extreme long-distance migrants, as embodied in, for example, the recently established Global Flyway Network, yields a two-pronged benefit: (1) on the basis of the unintended large-scale experiments carried out by humans, we rapidly come to grips with the selection pressures moulding the migration strategies of migrant birds, and (2) in applied contexts, the work gives instantaneous feedbacks on the conservation consequences of man-made alterations to wetland environments at the relevant global spatial scales.