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Forest fragmentation may benefit generalist herbivores by increasing access to various substitutable food resources, with potential consequences for their population dynamics. We studied a European roe deer ( Capreolus capreolus) population living in an agricultural mosaic of forest, woodlots, meadows and cultivated crops. We tested whether diet composition and quality varied spatially across the landscape using botanical analyses of rumen contents and chemical analyses of the plants consumed in relation to landscape metrics. In summer and non-mast winters, roe deer ate more cultivated seeds and less native forest browse with increasing availability of crops in the local landscape. This spatial variation resulted in contrasting diet quality, with more cell content and lower lignin and hemicellulose content (high quality) for individuals living in more open habitats. The pattern was less marked in the other seasons when diet composition, but not diet quality, was only weakly related to landscape structure. In mast autumns and winters, the consumption of acorns across the entire landscape resulted in a low level of differentiation in diet composition and quality. Our results reflect the ability of generalist species, such as roe deer, to adapt to the fragmentation of their forest habitat by exhibiting a plastic feeding behavior, enabling them to use supplementary resources available in the agricultural matrix. This flexibility confers nutritional advantages to individuals with access to cultivated fields when their native food resources are depleted or decline in quality (e.g. during non-mast years) and may explain local heterogeneities in individual phenotypic quality. [ABSTRACT FROM AUTHOR]

In this study, we sought to understand how landscape structure affects roe deer movements within their home-range in a heterogeneous and fragmented agricultural system of south-western France. We analysed the movements of 20 roe deer fitted with GPS collars which recorded their locations every 2-6 h over several months (mean = 9 months). Based on empirical observations and previous studies of roe deer habitat use, we hypothesised that roe deer should avoid buildings and roads, move preferentially along valley bottoms and through the more wooded areas of the landscape. To test these hypotheses we paired each observed movement step with 10 random ones. Using conditional logistic regression, we modelled a step selection function, which represents the probability of selecting a given step as a function of these landscape variables. The selectedmodel indicated thatmovements were influenced by all the tested landscape features, but not always in the predicted direction: our results suggested that roe deer tend to avoid buildings, roads, valley bottoms and possibly the more wooded areas (although the latter result should be interpreted with caution, as it may be influenced by a bias in the rate of GPS fix acquisition in woods). The distances to buildings and to roads were the most influential variables in the model, suggesting that the avoidance of potential sources of disturbancemay be a key factor in determining ranging behaviour of roe deer in human dominated landscapes. [ABSTRACT FROM AUTHOR]

The grey partridge Perdix perdix is of conservation concern owing to habitat heterogeneity losses and the negative impact of other environmental factors, e.g., pesticide use, predators, weather or shooting pressure, which are known to be associated with population decline. By an 11-year-period study in an intensively cultivated farmland located in the Paris basin, we aimed to relate the changes in grey partridge population dynamics with the changes in agriculture, monthly rainfall and shooting pressure. Summer drought occurred at the middle time of the study period. At the start of our study, a new cultivation, winter-wheat broadcast in maize-stubble fields, was introduced that probably improved the habitat. But in the next years, there was a loss in habitat diversity due to the disappearance of pastures dedicated to sheep rearing, removal of non-cropped areas and field boundaries and increase in the mean field size. Shooting was annually adjusted to what the owner believed to be a wise harvest. In post-breeding coveys, both percentages of hens with young among total hens and young-to-successful hens ratios first increased and then decreased. The mean brood size was rather weak during the dryness incident. The number of pairs in a more heterogeneous sector was always greater than in a less one. In both sectors, spring abundance first increased and then decreased. In the second half of the study period, the shooting quotas were reduced, especially when the mean brood size fell down. Low hatching rates of clutches and low chick survival rates explain the population decline, as the results are convincing. To stop the population decline in intensive arable farmland, good breeding success is needed. This can be provided by favourable habitats for hens to nest and for chicks to feed. [ABSTRACT FROM AUTHOR]

The decline of the European hare Lepus europaeus populations has been shown to be correlated with agricultural intensification, which has caused loss of habitat heterogeneity. We aimed to investigate the diurnal spring habitat selection using Jacobs’ second selection index in an intensively cultivated farmland to reveal how the habitat choice by resting hares was affected by changes in the habitat availability. Clearance counts of hares driven out of known areas were made during an 11-year field investigation within two sectors of a private hunting ground located in the Paris basin (France). The loss of habitat heterogeneity included the disappearance of pastures dedicated to a last remaining sheep farm in the area, the removal of non-cropped areas and field boundaries and the increase of mean field size. Breeding stocks of hare declined during the study. Harrowed fields were always avoided. Pastures, alfalfa fields, thickets and fallow land were selected at the start of our study, whereas the remaining part was avoided at the end. The preference for ploughed fields decreased with the growth of vegetation in the winter-wheat fields. To benefit hares, land management should provide year-round vegetative cover and food from non-cropped areas in intensive arable farms. [ABSTRACT FROM AUTHOR]

To determine the spatial resolution of Global Positioning System (GPS) receiver data, rigorous testing is essential. We tested performance of the Lotek 3300 GPS collar for medium-sized mammals (Lotek Engineering, Inc., Newmarket, ON, Canada). To mimic real wildlife monitoring situations, we performed both static (stationary receiver) and mobile tests, placing the receiver collar on a dog. We compared fix locations of the mobile receiver with the actual trajectory described by a portable Trimble high-precision GPS. We determined performance in relation to habitat type and leaf cover. Location error was habitat-dependent, with the best results in open habitat and much poorer ones in forest, particularly coniferous-dominated forest. For both static and mobile tests, location accuracy was higher when the number of satellites contacted was high and when the residual positional dilution of precision (PDOP) value was low. However, location error was highly variable, even for a given PDOP value and a given number of satellites contacted. Finally, mobile collars performed less well than their static counterparts, presumably because of frequent changes of GPS position and orientation. [ABSTRACT FROM AUTHOR]