Foraging behaviour

1. Honeybees are positively phototactic when they leave a feeding place and start to fly back to the hive. The strength of this natural phototactic response in individually marked bees was measured without interfering with their foraging behaviour. 2. Absolute sensitivity of this phototactic response to a point light source is in the range of 8.3 ▪ 10 7 quanta s-1 for 537 nm. This corresponds to about 5 absorbed quanta in 28 green receptors over the integration time of 60 ms. 3. We conclude that the properties of the mono-polar cells or higher order visual interneurons rather than those of the photoreceptors control the intensity dependence of the response because the slopes (n) of the response intensity functions (R / log I) are steep (n: 1.0-2.65) and wavelength dependent. Blue light (439 nm) causes the steepest function. 4. The effect of residual light adaptation on the R / log I-function and the spectral sensitivity (S(λ)) is negligible under the experimental conditions chosen, since the time course of dark adaptation is fast (τ ≤ 1 min). 5. The blue and green receptors contribute about equally to the S(λ) of this natural phototactic response, the UV receptors somewhat less (Fig. 5). 6. Colour mixing experiments, used to test colour vision in phototaxis, reveal no significant deviation from a simple linear summation of the quantal fluxes, irrespective of the spectral mixture used. We conclude, therefore, that under the experimental conditions colour vision is very unlikely to play a role in the phototactic behaviour of the honeybee. 7. All our results (steep R/log I-functions, fast dark adaptation, S(λ) and the absence of colour vision) support to notion that the natural phototactic response is controlled by neuronal pooling, most likely in the lamina M1 monopolar cells.

Mammals and birds adapt to prolonged fasting by mobilizing fat stores and minimizing protein loss. This strategy ends with an increase in protein utilization associated with behavioural changes promoting food foraging. Using the Zucker rat as a model, we have investigated the effect of severe obesity on this pattern of protein loss during long-term fasting. Two interactions between the initial adiposity and protein utilization were found. First, protein conservation was more effective in obese than in lean rats: fatty rats had a three times lower daily nitrogen excretion and proportion of energy expenditure deriving from proteins, and a lower daily protein loss in various muscles. This phase of protein sparing is moreover nine times longer in the fatty rats. Second, obese animals did not show the late increase in nitrogen excretion that occurred in their lean littermates. Total body protein loss during starvation was larger in fatty rats (57% versus 29%) and, accordingly, total protein loss was greater in their muscles. At the end of the experiment, lean and obese rats had lost 98% and 82%, respectively, of their initial lipid reserves, and fatty rats still had an obese body composition. These results support the hypothesis that in severely obese humans and animals a lethal cumulative protein loss is reached long before the exhaustion of fat stores, while the phase of protein conservation is still continuing. In contrast, in lean rats, survival of fasting seems to depend on the availability of lipid fuels. The data also suggest that accumulation of too much fat in wild animals is detrimental for survival, because it eliminates the late phase of increase in nitrogen excretion that is linked to a food foraging behaviour anticipating a lethal depletion of body reserves.

Increase in the usage of electronic gadgets has led to electropollution of the environment. Honeybee behaviour and biology has been affected by electrosmog since these insects have magnetite in their bodies which helps them in navigation. There are reports of sudden disappearance of bee populations from honeybee colonies. The reason is still not clear. We have compared the performance of honeybees in cellphone radiation exposed and unexposed colonies. A significant (p < 0.05) decline in colony strength and in the egg laying rate of the queen was observed. The behaviour of exposed foragers was negatively influenced by the exposure, there was neither honey nor pollen in the colony at the end of the experiment.

Foraging behaviour of wild coypu was studied to examine two hypotheses that had been previously proposed to explain the species' preference for aquatic plants. First, the nutritional benefit hypothesis which states that aquatic plants are more nutritional than terrestrial plants. Second, the behavioural trade-off hypothesis which states that coypus avoid foraging far from the water because of the costs associated with other types of behaviour. In order to test the nutritional benefit hypothesis, we studied the diet composition of coypus in relation to the protein content of the diet and of the plants available in the environment. Fieldwork was conducted seasonally from November 1999 to August 2000 at one study site located in the Province of Buenos Aires, east central Argentina. Behavioural observations showed that coypus remained foraging in the water and microhistological analysis of faeces indicated that their diet was principally composed of hygrophilic monocotyledons (Lemna spp. and Eleocharis spp.) throughout the year. We did not find support for the nutritional benefit hypothesis: nutritional quality (based on nitrogen content) of hygrophilic plants was not higher than that of terrestrial plants, and seasonal changes in diet quality did not match either fluctuations in vegetation quality or proportion of hygrophilic plants in the diet. Although not directly tested, the behavioural trade-off hypothesis may explain why coypus prefer to forage in or near the water as a mechanism for reducing predation risk. a We included the pteridophyte Azolla within the group of hygrophilic monocotyledons.

A tagging study was undertaken on Blood Reef off Durban, South Africa, to investigate movement patterns of Panulirus homarus rubellus as well as inshore/offshore population differences. Lobsters were collected by SCUBA divers and baited traps. Traps caught larger lobsters than divers and trap catches were somewhat male-dominated (40% female:60% male). Lobsters were predominately resident with only 3% of recaptured lobsters moving over 500 m. Long shore movements were probably related to foraging behaviour and sanding and scouring of reefs. Larger lobsters were caught on offshore reefs (!10 m depth) than on inshore reefs (B10 m depth). The absence of large lobsters (!100 mm carapace length, CL) on inshore reefs may be related to fishing mortality. Low juvenile numbers (B50 mm CL) on offshore reefs suggest that post-larval lobsters settle on inshore reefs. An exponential decay model indicated that a small percentage of the population (males: 1.3%; females: 2.5%) move offshore with females mainly moving at 3 years of age and males between 1 and 3 years of age.

Geographic profiling (GP) was originally developed as a statistical tool to help police forces prioritize lists of suspects in investigations of serial crimes. GP uses the location of related crime sites to make inferences about where the offender is most likely to live, and has been extremely successful in criminology. Here, we show how GP is applicable to experimental studies of animal foraging, using the bumble-bee Bombus terrestris. GP techniques enable us to simplify complex patterns of spatial data down to a small number of parameters (2-3) for rigorous hypothesis testing. Combining computer model simulations and experimental observation of foraging bumble-bees, we demonstrate that GP can be used to discriminate between foraging patterns resulting from (i) different hypothetical foraging algorithms and (ii) different food item (flower) densities. We also demonstrate that combining experimental and simulated data can be used to elucidate animal foraging strategies: specifically that the foraging patterns of real bumble-bees can be reliably discriminated from three out of nine hypothetical foraging algorithms. We suggest that experimental systems, like foraging bees, could be used to test and refine GP model predictions, and that GP offers a useful technique to analyse spatial animal behaviour data in both the laboratory and field.

Like most large grazing herbivores, horses select their food based on visual cues, odour, taste, texture, availability and variety. There is relatively little published information about the role of flavour in diet selection by domestic horses in comparison with other domestic and companion animals. However, previous trials investigating effects of diet flavour in stabled horses indicated significant effects on foraging behaviour and selection. In this series of three trials we aimed to determine relative acceptance by presenting flavour preference tests to eight horses. Horses were stabled and fed hay ad lib on trial data collection days plus a standard unflavoured concentrate ration at 7:30 a.m. In Trial 1, 15 flavours were separately presented in standard 100 g cereal by-product meals and the trial was replicated. Quantity consumed, time of completion, partial rejection or refusal were recorded. Order of presentation was determined by a Latin Square design. Trial data were collected on five sampling days, separated by a minimum of 1 day. Horses were presented with six flavoured meals daily; minimum 1 h between the meals. Twelve flavours were universally accepted and of these the eight flavours with fastest mean consumption times (banana, carrot, cherry, cumin, fenugreek, oregano, peppermint and rosemary) were presented in paired preference tests in Trial 2. In Trial 2, all paired combinations of the eight flavours were presented, in two tests per day at noon and 4 p.m. Presentations of the same flavour were separated by at least 1 day. Paired presentations were in 300 g cereal by-product. Presentations were terminated when approximately half of the total amount presented had been consumed. Flavour preferences were expressed as a ratio from 0 www.elsevier.com/locate/applanim

A new population-based search algorithm called the Bees Algorithm (BA) is presented. The algorithm mimics the food foraging behaviour of swarms of honey bees. In its basic version, the algorithm performs a kind of neighbourhood search combined with random search and can be used for both combinatorial optimisation and functional optimisation. This paper focuses on the latter. Following a description of the algorithm, the paper gives the results obtained for a number of benchmark problems demonstrating the efficiency and robustness of the new algorithm.

The invasive Clethra arborea has a dualrole in the diet of the Azores bullfinch, a critically endangered bird species endemic to the island of São Miguel (Azores, Portugal). This is a crucial winter food resource but it lowers the availability of native laurel forest species that compose most of the bird's diet throughout the year. The removal of this and other invasive alien species is part of current laurel forest habitat restoration programmes, disregarding the impact on the Azores bullfinch population. In order to evaluate the first responses of the Azores bullfinch to habitat restoration, we studied bird diet, foraging behaviour, food availability and habitat occupancy in managed (without C. arborea) and control areas. Significant increases in the availability of native food resources in managed areas were noticeable in the diet, particularly the intake of Ilex perado ssp. azorica and Prunus lusitanica ssp. azorica flower buds. In most of the studied months birds heavily used and foraged in managed over control areas. The one exception was in December, when a resource-gap occurred in managed areas, which may be overcome in the short-term due to re-establishment of native plants following removal of invasive aliens.

Increase in the usage of electronic gadgets has led to electropollution of the environment. Honeybee behaviour and biology has been affected by electrosmog since these insects have magnetite in their bodies which helps them in navigation. There are reports of sudden disappearance of bee populations from honeybee colonies. The reason is still not clear. We have compared the performance of honeybees in cellphone radiation exposed and unexposed colonies. A significant (p < 0.05) decline in colony strength and in the egg laying rate of the queen was observed. The behaviour of exposed foragers was negatively influenced by the exposure, there was neither honey nor pollen in the colony at the end of the experiment.

Amongst the benefits of foraging in flocks are the enhancement of food finding and predation avoidance. Characteristics such as size, individual position, as well as position and distance between members are factors that may influence vigilance and foraging. In a study using scaled doves, Columbina squammata, I observed a negative correlation between group size and vigilance and a positive correlation with time spent foraging, which suggests a reduction of costs and an increase of benefits as a consequence of larger group sizes. Individual position in the flock appeared to be an important factor in this trade-off. Peripheral individuals were more vigilant and foraged less than central ones, suggesting an edge effect in flocks of this species. The clustering of conspecifics may be related with fast transmission of information. Overall, aggressive interactions were rarely observed; when registered, they occurred mostly in larger groups, suggesting an effect of interference competition. These results imply that predation may be a strong pressure on the scaled dove's flock formation and behaviour.

Factors associated with management and logging practices are of particular interest in the perspective of biodiversity management. In this study we focused on overwintering birds of two close and contrasting forest habitats: a 60-120 years old oak forest and a secondary 10-20 years old wood that has lost most of its original vegetation because of continuous logging and is now dominated by an introduced species, black locust Robinia pseudoacacia. We examined bird use of the forests over two levels: species-habitat relationships and foraging niches. The former were assessed by means of point counts centred in 50 m radius plots, whereas the latter by observations of foraging behaviour and plant species exploitation. Mean species richness, diversity and abundance of bark foragers was significantly greater in the old-growth stand, where trees were higher and larger but stem density was lower. Almost no wintering bird species occurred at higher density in the second-growth than in old-growth forest, and no foraging birds positively selected the black locust as substrate. Despite the observed differences in biodiversity metrics and plant species exploitation, most birds of the two stands showed few shifts in their foraging behaviour (in terms of foraging technique, substrate, relative horizontal and vertical position) and niche metrics (breadth and overlap). By considering results obtained with the two approaches, we suggest that biodiversity of altered secondary woods can be increased if current silvicultural practices are modified towards (1) maintaining oaks or trees prone to snag formation such as old poplars and (2) preventing black locust establishment in post-clearcut communities. #

We investigated (1) the importance of chemical cues for predator detection by the nocturnal, rock-dwelling velvet gecko, Oedura lesueurii, and (2) how the lizards' responses to snake odour may have exerted selection on the foraging behaviours of a nocturnal elapid snake. This snake species (broadheaded snake, Hoplocephalus bungaroides) feeds primarily on velvet geckos, and does so by means of a distinctive foraging behaviour: the snakes remain sedentary in rock crevices for days or weeks, waiting to ambush geckos. Behavioural assays showed that geckos that are sympatric with this sedentary 'ambush' predator can detect and respond to the scent of the snake. Retreat-site selection experiments showed that geckos are less likely to enter crevices if the snake's scent is distributed over the entire rock surface, rather than localized to a central portion. Together, these data support the notion that the 'ambush' predator benefits by remaining sedentary within a retreat-site for long periods, because it thereby minimizes the extent to which it spreads its scent over the rocks forming the crevice. Geckos from a population sympatric with the 'ambush' predator responded strongly to the snake scent, but those from an allopatric population did not. Additionally, geckos from sympatric populations were able to detect the scent of a nocturnal snake that does not eat geckos (small-eyed snake, Rhinoplocephalus nigrescens), but did not modify their retreat-site selection or locomotory behaviours in response to this cue. Lizards from allopatric populations apparently did not detect the scent of small-eyed snakes. Collectively, our findings support an interpretation of predator-prey coevolution in the present system, and emphasize the importance of chemosensory cues to these rock-dwelling reptiles.

Conversion of natural habitats to human settlements creates an alternative habitat with different bio-physical characteristics such as micro-climatic conditions and resource availability. Deserts are especially sensitive to such effects due to generally low nutrient levels and water availability. Gardens in human settlements in the desert are often a main source of alien plant species that provide ample foraging resources year round. These changes in floral composition and availability may alter pollinator community composition and foraging behaviour, as well as pollination network characteristics. We investigated the effects of desert gardening on pollinator communities and pollination networks in the Jordan Rift Valley (Israel), an arid agro-natural landscape south of the Dead Sea. We studied seasonal diversity patterns of plants and wild bees in natural habitats and in gardens in settlements. Wild bees and blooming plants were sampled from February to July in 2007 and in 2008. We constructed plant-pollinator networks and compared bee communities between the two habitat types along the season. We found that bee abundance was greater in the gardens, and that rarefied bee species richness was greater in the natural habitat. Bee species richness and abundance exhibited contrasting seasonal patterns between habitats. Bee community composition also differed greatly between habitats, and species in the gardens had a generally wider geographical range in comparison to species in the natural habitat. We also found a higher level of generalisation of the pollination network in the gardens compared to the natural habitat, which may indicate a response to a disturbed and unstable environment. We conclude that gardening in deserts although promoting overall bee abundance, negatively affects species richness and changes community composition and network characteristics, with possible implications on the composition of native flora in the natural habitat surrounding the gardens. A. Gotlieb et al. / Basic and Applied Ecology 12 (2011) 310-320 311 2008 erfasst. Wir konstruierten Diagramme der Pflanzen-Bestäuber-Netzwerke und verglichen die Bienengemeinschaften der beiden Habitattypen im Laufe der Saison. Wir fanden, dass die Bienenabundanz in den Gärten größer war und dass die rarefizierte Artenzahl in den natürlichen Habitaten höher war. Artenreichtum und Abundanz der Bienen zeigten unterschiedliche jahreszeitliche Muster. Die Zusammensetzung der Bienengemeinschaften der beiden Habitattypen war ebenfalls unterschiedlich. Die Arten der Gärten hatten ein größeres geographisches Verbreitungsgebiet als die Arten des natürlichen Habitats. Im Vergleich zum natürlichen Habitat fanden wir auch einen höheren Grad der Generalisierung im Pollinationsnetzwerk der Gärten. Dies könnte ein Indikator für eine gestörte, instabile Umwelt sein. Wir folgern, dass das Anlegen von Gärten in Wüsten, obwohl die Gesamtbienenabundanz erhöht wird, den Artenreichtum negativ beeinflusst sowie Artenzusammensetzung und Netzwerkeigenschaften verändert, was Auswirkungen auf die einheimische Flora der natürlichen Habitate in der Umgebung von Gärten haben kann.

—In this paper an overview of the areas where the Bee Colony Optimization (BCO) and its variants are applied have been given. Bee System was identified by Sato and Hagiwara in 1997 and the Bee Colony Optimization (BCO) was identified by Lucic and Teodorovic in 2001. BCO has emerged as a specialized class of Swarm Intelligence with bees as agents. It is an emerging field for researchers in the field of optimization problems because it provides immense problem solving scope for combinatorial and NP-hard problems. BCO is one of the benchmark systems portraying team work, collaborative work. BCO is a bottom-up approach of modeling where agents form global solution by optimizing the local solution.

Activity pattern, activity budget and foraging behaviour are compared between radiotagged squirrels in a coniferous and a deciduous habitat. Differences between habitats are explained in terms of differences in food availability, food choice and feeding rate.

The winter diet and foraging range of gentoo penguins, Pygoscelis papua, were studied at Kidney Cove, Falkland Islands. The mean wet mass of the 56 stomach-content samples collected from May to October was 32.7±47.4 g. The diet consisted generally of cephalopods, crustaceans and fish, as well as two other molluscs. Among the six cephalopod species identified, the commercially fished Patagonian squid, Loligo gahi, had the highest abundance and was also the main prey by reconstituted mass (53% of the total reconstituted mass). Lobster krill, Munida gregaria, one of five species of crustaceans, was the most abundant prey species by frequency of occurrence and by number (68% and 60%, respectively). Rock cod, Patagonotothen ramsayi, accounted for the majority of the fish diet with 34% of the total reconstituted mass. Most prey species identified in the winter diet were also abundant diet components during the breeding season. However, the known biology of the prey species and their rate of digestion indicated that, in winter, adults may forage further offshore than during the breeding season. This assumption was supported by the results obtained from two birds satellite-tracked during the study period. Both birds remained mainly in inshore waters and returned frequently ashore, but one penguin foraged up to 276 km from the coast. The differences in the foraging behaviour of the two birds were reflected in significant differences with regard to time spent underwater, distance travelled per day and calculated travelling speed. Furthermore, the progress of cohorts of L. gahi over the winter is consistent with results from life-cycle studies in this region and suggests that birds have been foraging in the feeding grounds of L. gahi.

We examined how seabirds might be used to study marine environmental variables, which necessitates knowing location and the value of the variable to be studied. Five systems can potentially be used for determination of location: VHF (Very High Frequency) telemetry, PTT (Platform Terminal Transmitters) telemetry, GLS (Global Location Service) geolocation methods, dead reckoning and GPS (Global Positioning System), each with its own advantages with respect to accuracy, potential number of fixes and size. Temperature and light were used to illustrate potential difficulties in recording environmental variables. Systems currently used on seabirds for measurement of temperature respond slowly to environmental changes; thus, they may not measure sea surface temperature adequately when contact periods with water bodies are too short. Light can be easily measured for light extinction studies, but sensor orientation plays a large role in determining recorded values. Both problems can be corrected. The foraging behaviour of seabirds was also examined in order to identify those features which would be useful for determination of marine environmental variables at a variety of spatial and temporal scales. Area coverage by birds is highly dependent on breeding phase and tends to be concentrated in areas where prey acquisition is particularly enhanced. The identification of these sites may be of particular interest to marine biologists. 'Plungers' and 'divers' are potentially most useful for assessment of variables deeper within the water column, with some divers spending up to 90% of their time sub-surface. Few seabirds exploit the water column deeper than 20 m, although some divers regularly exceed 50 m (primarily penguins and auks), while 2 species dive in excess of 300 m. The wide-ranging behaviour of seabirds coupled, in many instances, with their substantial body size makes them potentially excellent carriers of sophisticated environmental measuring technology; however, the ethical question of how much the well-being of birds can, and should, be compromised by such an approach needs to be carefully considered.

Understanding the mechanisms that link prey availability to predator behaviour and population change is central to projecting how a species may respond to future environmental pressures. We documented the behavioural responses and breeding investment of macaroni penguins Eudyptes chrysolophus across five breeding seasons where local prey density changed by five-fold; from very low to highly abundant. When prey availability was low, foraging trips were significantly longer and extended overnight. Birds also foraged farther from the colony, potentially in order to reach more distant foraging grounds and allow for increased search times. These extended foraging trips were also linked to a marked decrease in fledgling weights, most likely associated with reduced rates of provisioning. Furthermore , by comparing our results with previous work on this population, it appears that lowered first-year survival rates associated, at least partially, with fledging masses were also evident for this cohort. This study integrates a unique set of prey density, predator behaviour and predator breeding investment data to highlight a possible behavioural mechanism linking perturbations in prey availability to population demography.

Large areas of natural and semi-natural habitats are exposed to artificial illumination from adjacent urban areas and roads. Estuarine and coastal wetlands are particularly exposed to such illumination because shorelines often are heavily utilized by man. However, the impact of artificial illumination on the waders that forage in these highly productive habitats is virtually unknown. We evaluated the effects of artificial illumination on the nocturnal habitat selection and foraging behaviour of six wader species with different feeding strategies: three visual foragers, two species that alternate visual and tactile strategies (mixed foragers), and one tactile forager. We quantified the number of birds and their foraging behaviour at sites affected and not affected by streetlights, and also before and after illuminating experimental sites. Areas illuminated by streetlights were used more during the night by visual foragers, and to a lesser extent by mixed foragers, than non-illuminated areas. Visual foragers increased their foraging effort in illuminated areas, and mixed foragers changed to more efficient visual foraging strategies. These behavioural shifts improved prey intake rate by an average of 83% in visual and mixed foragers. We have showed that artificial illumination has a positive effect on the nocturnal foraging of waders, but on the other hand may draw them to degraded areas close to urban centres, and potentially raises their exposure to predators. Our findings suggest that artificial illumination is worth investigation as a tool in the management of intertidal habitats for waders.

Increasing the level of physical exercise in broilers has been indicated to improve leg condition. We attempted to stimulate locomotor and foraging activities by adding environmental complexity to experimental broiler pens. We hypothesised that adding barriers between food and water, and stimulating foraging behaviour would increase level of physical activity. To test this hypothesis, 1800 male broilers (1-day-old) were divided into 40 groups of 45 birds (10 birds/m 2 ). Each group was assigned to one of four treatments in a randomised block design with 10 replicates as follows: barrier treatment (B) contained three barriers placed between the drinkers and the feeder. The light treatment (L) consisted of brightly coloured moving lights projected on the pen¯oor for four 1 h periods per day throughout rearing. Whole wheat was dispersed on the¯oor from day 8 to day 17 in the wheat treatment (W). Control birds (C) were maintained under standard management practices. Five focal birds per pen (200 birds total) were observed by focal sampling during 3 min per week, from 1 to 6 weeks of age. The behavioural data were analysed using repeated measures ANOVA. B birds spent 9:7 AE 2:1% of time perching, spent less time lying than L and W birds (P < 0:05) and changed their feeding and drinking patterns (fewer observation periods containing bouts of both eating and drinking than C birds, P < 0:05). Neither L or W treatments enhanced foraging and locomotion. However, L birds spent more time eating than C birds (P < 0:05). The behaviour of W birds did not differ from the controls. Increasing environmental complexity modi®ed the behaviour and the organisation of feeding and drinking patterns in B and L birds. Perching behaviour was high in the presence of barriers, which may have bene®cial effects on the welfare of the birds since it stimulated greater variety of motor patterns. Effects of moving lights and scattering wheat in the litter were unclear or non-existent. However, further studies need to be conducted to determine if this type of enrichment could help to improve animal welfare. #

A behavioural study was conducted on 47 lion-tailed macaques housed in 13 zoos across India. An ethogram was constructed and behavioural observations conducted using qualitative sampling ad libitum, focal animal sampling and instantaneous scans. Sampling was conducted only during the day when visitors were present at the macaque enclosures. Stereotypic pacing was the most commonly exhibited behaviour. Abnormal behaviours were only exhibited by individuals that were confiscated from private owners and those that were born in zoos but never by animals caught from the wild. Active foraging behaviours, in turn, were influenced by an individual's gender and enclosure complexity. Female macaques autogroomed and lip-smacked more frequently than males, while individuals housed in groups initiated relatively more bouts of allogrooming than those housed in pairs. In general, the observed influence of environmental factors and social deprivation on the development of behavioural pathologies in lion-tailed macaques in Indian zoos emphasise the need for improving the current husbandry protocols and management practices for the improved welfare of these animals. #

An ethogram was developed for the foraging Cape pangolin in order to construct activity budgets. Behaviour was classified into seven categories and nine types of feeding sites were recorded. Activity budgets of animals foraging in different vegetation types are presented to illustrate the importance of vegetation on behaviour patterns and feeding site utilization. Availability of feeding sites may depend on the vegetation type with trees, shrubs and woody debris comprising most feeding sites. Seven prey species were recorded. One animal displayed strictly diurnal activity which suggests greater variability in activity patterns than previously thought.

Over the past 50 years European populations of the lesser horseshoe bat Rhinolophus hipposideros have severely declined, probably because of the loss of foraging habitat. To date, studies of the foraging behaviour of this species have been limited as its low mass (4±8 g) precluded the use of radio-telemetry because commercially available radio-transmitters exceeded 10% of its body mass. In this study, radiotransmitters weighing < 0.35 g were built. These increased the body mass of the animals from 4.5% to 8.1%, with no demonstrable adverse effect on their¯ight behaviour. The habitat selection of eight female lesser horseshoe bats was studied in Monmouthshire, U.K. The bats had foraging ranges between 12 and 53 ha (100% kernel). Although one bat foraged 4.2 km from the roost, for 50% of the time tracked bats were recorded within 600 m of the nursery roost. The estimated density within 200 m of the roost was 5.8 foraging bats/ha. This decreased to 0.01 bats/ha at 1200 m. Compositional analysis revealed that this species used woodlands, predominately broadleaf, more than any other habitat. In addition, the bats foraged in areas of high habitat diversity. Conservation management of this species should concentrate on such areas within 2.5 km of the nursery roost.

The foraging behaviour of conspecific female Antarctic fur seals (AFS) was compared simultaneously at 2 breeding colonies at Îles Kerguelen (S Indian Ocean). A remnant colony at ÎIes Nuageuses (IN) thought to have escaped sealing is hypothesized to be the source of increasing fur seal numbers at Cap Noir (CN) on the Kerguelen mainland. Inter-annual variability in foraging areas is known to occur in response to local oceanographic changes at CN. Given the distance between the 2 sites (~160 km), we hypothesize that seals from the 2 colonies may show spatial segregation in foraging due to variability in local prey resource availability, although the transfer of foraging knowledge between sites via emigration may override such behaviour. The foraging zones, diving activity, diet and foraging success of seals were compared between sites using satellite telemetry, dive recorders and faecal analysis. No evidence of spatial foraging overlap was observed, with seals from IN conducting longer foraging trips, typified by a longer initial transit phase, than CN seals, which spent less time diving at night and dived more deeply. Pups nevertheless received higher absolute and daily energy delivery rates at IN. Diet was superficially similar at ~98% myctophid consumption; however, IN seals favoured the high-energy Gymnoscopelus nicholsi, indicating that local heterogeneity in marine resources likely influences the foraging zone choice of AFS. Finally, distribution patterns of 54 female AFS tracked during summer months from 1998 to 2006 reveal the importance of both on-shelf (< 500 m) and shelf-break regions as foraging habitat. The core foraging area for CN in all years (10 400 km 2 ) was small (~10% of total foraging space); however, time spent in this region alone totaled 38%. The likelihood of spatial overlap in foraging range is higher on the east coast of Kerguelen.

Feeding preferences of nectarivorous ants for sugars and amino acids were studied in an Australian tropical rain forest using artificial nectar solutions. Fifty-one ant species were recorded feeding on the solutions. 2. Preferences among carbohydrates were principally concordant between ant species. In paired tests, sucrose was often preferred over fructose, glucose, maltose, melezitose, raffinose and xylose, respectively. Attractiveness of sucrose baits increased with concentration. 3. Many ant species preferred sugar solutions containing mixtures of amino acids over pure sugar solutions. However, preferences among seven pairs of single amino acids in sugar solutions differed substantially between ant species, including several cases where different ant species displayed significant opposite choices. 4. Ant selectivity between solutions was significantly reduced when different ant species co-occurred on the same bait. Preferences for single amino acids were also reduced when colonies fed extensively on the same compound prior to the experiment for 2 days.

Space usage by animals may be influenced by a range of factors. In this study we investigate whether foraging behaviour affects the home range size of lizards. Two distinct tactics of foraging have been recognized in predators: sitand-wait foraging (SW) and active foraging (AF). Foraging activity level of a data set of lizard species, mainly compiled from literature, is compared with their home range sizes. Two opposite predictions can be made about foraging in connection with home range area: on the one hand, SW species may exhibit larger home ranges due to their mating system; on the other hand, AF species have higher metabolic energy and thus food requirements and can be expected to have larger home ranges that have to yield this food. This study shows that percentage of the time moving (as an index of foraging mode) correlates positively with home range, even after correcting for body mass, and these patterns remain when phylogenetic relationships are taken into account. We thus conclude that home range areas parallel activity levels in lizards. r

Flight performance and echolocation behaviour of the pond bat, Myotis dasycneme (Boie, 1825), were investigated over canals and a lake in the Netherlands. Multi-flash stereophotogrammetry, linked with synchronous recording of echolocation calls, was used to reconstruct the three-dimensional flight paths of bats and to correlate flight behaviour with changes in pulse emission during echolocation. Echolocation calls during commuting flight at the canal were sigmoidal in structure, with an initial steep frequency modulated (FM) sweep followed by a more shallow sweep, ending with a second, rapid FM sweep. Similar calls were produced during the search phase of foraging, though longer duration quasi-CF (constant-frequency) calls, with longer interpulse intervals and much reduced initial and final FM sweeps, were produced by bats hunting over a large lake. Overall, calls were generally lower in frequency, with significantly longer pulse durations and interpulse intervals, compared with those of smaller trawling Myotis bats. Flight speeds were compared with predicted optima from aerodynamic models. Commuting bats exceeded predicted maximum range speed, which was considerably higher than that noted for other smaller species of trawling Myotis. Flight speed was significantly higher closer to the roost, at a narrower canal site. A negative correlation between wingbeat frequency and flight speed, and a facultative 1: 1 link between pulse emission and wingbeat during search phase were established. During commuting, the bats flew at a height above that which would normally confer substantial power savings through ground effect. It is argued that, by flying at a lower height, bats would compromise commuting speed. Echolocation calls produced during attempted prey capture were remarkably similar in design to those produced by those other Myotis species that forage in a similar fashion. Prey was detected at 2 m, and reaction distance was 1.8 m. Evidence of a physiological limit on pulse duration and interpulse interval during prey capture is presented. Overlap of emitted pulse and received echo may degrade the performance of echolocation in many bats, and overlap is generally avoided in M. dasycneme except perhaps when the bat is very close to the prey item.

The diet of barbastelle bats, Barbastella (b.) barbastellus and B. (b.) teucomelas, captured, respectively, in the Swiss Alps and in the Kirghiz Tien Shian and Pamir mountains (central Asia) was investigated through faecal analysis. Location of hunting habitats and data on foraging behaviour of Swiss barbastelle bats were obtained from radiotracking. In either area, ca. 99% of prey by volume consisted of Lepidoptera. The regular occurrence of one small arctiid species in the diet of Swiss barbastelles, as well as the predominance (84%) of tympanate moths among the Lepidoptera sampled at foraging sites suggest that B. barbastellus could prey to a large extent on smaller tympanate moths.

We attached 11 g (1.4% body-mass equivalent) global location sensing (GLS) archival tag packages to tarsi of 25 breeding sooty shearwaters (Puffinus griseus, titi) on Whenua Hou (Codfish Island), New Zealand during the chick-rearing period in 2005. Compared with chicks reared by non-handled adults that did not carry tags, deployment of tags on one or both adult parents ultimately resulted in 35% reduction in chick body mass and significantly reduced chick skeletal size preceding fledging (

The heredity of rover/sitter, a naturally occurring polymorphism in the locomotory component of Drosophila melanogaster third instar larval foraging behaviour was analysed by comparing 16 reciprocal crosses made using isogenjc rover and sitter parental strains. Results from both male and female data sets indicated that rover/sitter differences have an autosomal basis, with rover showing complete dominance over sitter. The Y-chromosome, permanent cytoplasmic factors, transient maternal factors and interactions between them made no significant contributions to rover/sitter inheritance. A minor X-chromosome effect was observed in the female data. Rover/sitter ratios in both males and females of the 16 reciprocal crosses were not significantly different from those expected assuming a one gene, complete dominance model of autosomal inheritance.

To cite this Article: Vasilakis, Dimitris P., Poirazidis, Konstantinos S. and Elorriaga, Javier N. (2008) 'Range use of a Eurasian black vulture (Aegypius monachus) population in the Dadia-Lefkimi-Soufli National Park and the adjacent areas,