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Robinson Elva J H EJ Laboratory of Apiculture and Social Insects, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK. - - 2005
Forager ants lay attractive trail pheromones to guide nestmates to food, but the effectiveness of foraging networks might be improved if pheromones could also be used to repel foragers from unrewarding routes. Here we present empirical evidence for such a negative trail pheromone, deployed by Pharaoh's ants (Monomorium pharaonis) as ...
Vlasak Anna N - - 2006
Locating food and refuge is essential for an animal's survival. However, little is known how mammals navigate under natural conditions and cope with given environmental constraints. In a series of six experiments, I investigated landmark-based navigation in free-ranging Columbian ground squirrels (Spermophilus columbianus). Squirrels were trained individually to find a ...
Wiersma Popko - - 2005
Understanding the effect of food availability on food requirements is critical when linking food availability e.g. to reproduction or habitat selection. Decreasing intake rate (intake per unit foraging effort) can be expected to increase daily energy expenditure (DEE), due to increased foraging costs. However, all the studies we could find ...
Maloney Shane K - - 2005
The nychthemeral activity patterns of a population of female black wildebeest inhabiting a shadeless environment were surveyed periodically over 1 year. The wildebeest fed mostly at night, with the proportion of feeding at night increasing when ambient conditions were hotter. Inactive periods were spent mostly lying during cooler weather but ...
Grémillet David - - 2005
Warm-blooded diving animals wintering in polar regions are expected to show a high degree of morphological adaptation allowing efficient thermal insulation. In stark contrast to other marine mammals and seabirds living at high latitudes, Arctic great cormorants Phalacrocorax carbo have very limited thermal insulation because of their partly permeable plumage. ...
Vladusich Tony - - 2005
How do honeybees use visual odometry and goal-defining landmarks to guide food search? In one experiment, bees were trained to forage in an optic-flow-rich tunnel with a landmark positioned directly above the feeder. Subsequent food-search tests indicated that bees searched much more accurately when both odometric and landmark cues were ...
Wolf Harald - - 2005
During foraging trips, desert ants Cataglyphis fortis do not rely only on their well-studied path integration system, they also use olfactory cues when approaching a familiar food source. When a wind is blowing from a constant direction, as is characteristic of their desert habitat, the ants do not approach the ...
Bakker E S - - 2005
The relative importance of predation risk and food quality on spatial grazing pressure and activity patterns was tested in a central-place foraging herbivore: the European rabbit. Rabbits grazed less with increasing distance from their burrows into adjacent grassland, thereby creating a gradient of increasing vegetation height and plant biomass and ...
Warburton, LS; Research Centre ...
Foraging behaviour and feeding ecology of the Black-cheeked Lovebird <i>Agapornis nigrigenis</i> were studied in Zambia. The birds fed on at least 39 species, and food items included seeds, leaves, flowers (especially nectar), fruit pulp, invertebrates, bark, lichen and resin. Terrestrial foraging was dominant, whereas arboreal foraging varied seasonally and in ...
Pravosudov Vladimir V - - 2006
Food caching has been linked to better performance on spatial memory tasks and enlarged hippocampal volume in both birds and mammals. Within food-caching birds, it has also been predicted that species less reliant on stored food should have inferior spatial memory and a smaller hippocampus compared to species that depend ...
Millor J - - 2006
Amplification is the main component of many collective phenomena in social and gregarious insects. In a society, individuals face a mixed palette of odours coming from different groups (lines, strains) and individuals present discrimination capabilities. However, often at the collective level, different groups may cooperate and act together. To understand ...
Nieh James C - - 2005
Stingless bees (Apidae, Meliponini) can recruit nestmates to good food sources. We present the first data showing that recruiting meliponine foragers at feeders and inside nests regulate their thoracic temperature according to net food profitability. Using infrared thermography, we found that Melipona panamica foragers elevated their thoracic temperature at profitable ...
De Marco Rodrigo - - 2005
Apis mellifera bees execute waggle dances to recruit other bees to desirable food sources. Several components of the waggle dance are correlated with the direction of and the distance to food. Moreover, recruits use the spatial information encoded in the dance to locate the signalled food. However, although dance communication ...
Kümmerli Rolf - - 2005
In polygynous (multiple queens per nest) ants, queen dispersal is often limited with young queens being recruited within the parental colony. This mode of dispersal leads to local resource competition between nestmate queens and is frequently associated with extremely male-biased sex ratios at the population level. The queen-replenishment hypothesis has ...
O'Malley Robert C - - 2005
Observed patterns of variability in the food-processing behavior of white-faced capuchins (Cebus capucinus) across populations may reflect foraging traditions. However, there has been relatively little attention given to intrapopulation variability in food processing among groups and age/sex classes, making recent cross-population comparisons difficult to interpret. In this paper, we provide ...
Goyret Joaquín - - 2005
Nectar acquisition in the honeybee Apis mellifera is a partitioned task in which foragers gather nectar and bring it to the hive, where nest mates unload via trophallaxis (i.e. mouth-to-mouth transfer) the collected food for further storage. Because forager mates exploit different feeding places simultaneously, this study addresses the question ...
Ceccarelli Daniela M - - 2005
Herbivorous fishes have been attributed a central role in structuring benthic communities on coral reefs. However, the relative importance of different behavioural groups of herbivores may differ and their interactions may be complex. This study focuses on an experiment that discriminates between two groups of herbivorous fish: (1) "Foragers" (relatively ...
Soligo Christophe - - 2005
The aye-aye (Daubentonia madagascariensis) is easily the most enigmatic of living primates. It sports a unique combination of derived characters, including continuously growing incisors, functional claws, the largest hand of any primate and a highly modified middle finger. The specialised middle finger is no longer used in locomotion and serves ...
Arab Alberto - - 2005
Using bidimensional arenas, the construction and spatial dispersion of tunnels constructed by Coptotermes gestroi and Heterotermes tenuis (Rhinotermitidae) was determined under different laboratory conditions. Workers of both species showed an increase of the tunneled area with the rise in temperature. The activity of workers of C. gestroi also increased with ...
Stenberg Marika - - 2005
Animals foraging in heterogeneous environments benefit from information on local resource density because it allows allocation of foraging effort to rich patches. In foraging groups, this information may be obtained by individuals through sampling or by observing the foraging behaviour of group members. We studied the foraging behaviour of goldfish ...
Dechaume-Moncharmont François-Xavier - - 2005
Many animals nest or roost colonially. At the start of a potential foraging period, they may set out independently or await information from returning foragers. When should such individuals act independently and when should they wait for information? In a social insect colony, for example, information transfer may greatly increase ...
Bugnyar Thomas - - 2005
Human social behaviour is influenced by attributing mental states to others. It is debated whether and to what extent such skills might occur in non-human animals. We here test for the possibility of ravens attributing knowledge about the location of food to potential competitors. In our experiments, we capitalize on ...
Granero Angeles Mena - - 2005
When the frenzied and irregular food-recruitment dances of bumblebees were first discovered, it was thought that they might represent an evolutionary prototype to the honeybee waggle dance. It later emerged that the primary function of the bumblebee dance was the distribution of an alerting pheromone. Here, we identify the chemical ...
Dussutour Audrey - - 2005
Foraging in ants is generally organized along well-defined trails supporting a bi-directional flow of outbound and nestbound individuals and one can hypothesize that this flow is maximized to ensure a high rate of food return to the nest. In this paper we examine the effect of bottlenecks on the temporal ...
Green Jonathan A - - 2005
Aquatic birds have access to limited amounts of usable oxygen when they forage (dive) underwater, so the major physiological constraint to their behaviour is the need to periodically visit the water surface to replenish these stores and remove accumulated carbon dioxide. The size of the oxygen stores and the rate ...
Devenport Jill A - - 2005
The variability of most environments taxes foraging decisions by increasing the uncertainty of the information available. One solution to the problem is to use dynamic averaging, as do some granivores and carnivores. Arguably, the same strategy could be useful for grazing herbivores, even though their food renews and is more ...
Beekman Madeleine - - 2005
Honey bee foragers communicate the direction and distance of both food sources and new nest sites to nest mates by means of a symbolic dance language. Interestingly, the precision by which dancers transfer directional information is negatively correlated with the distance to the advertised food source. The 'tuned-error' hypothesis suggests ...
Beekman Madeleine - - 2005
Honey bees utilise floral food sources that vary temporally in their relative and absolute quality. Via a sophisticated colony organisation, a honey bee colony allocates its foragers such that the colony focuses on the most profitable forage sites while keeping track of changes within its foraging environment. One important mechanism ...
Hahn Steffen - - 2005
Foraging decisions depend not only on simple maximization of energy intake but also on parallel fitness-relevant activities that change the forager's 'state'. We characterized patch use and patch leaving rules of a top-predatory seabird, the Brown Skua (Catharacta antarctica lonnbergi), which during its reproductive period in the Antarctic establishes feeding ...
Riley J R - - 2005
In the 'dance language' of honeybees, the dancer generates a specific, coded message that describes the direction and distance from the hive of a new food source, and this message is displaced in both space and time from the dancer's discovery of that source. Karl von Frisch concluded that bees ...
Boulay R - - 2005
The seeds of many plant species present a food body that is consumed by animal dispersers. In theory, if the animals are polyphagous, the availability of alternative food resource other than the diaspore itself may influence its dispersal and survival. We used the myrmecochore Helleborus foetidus L. (Ranunculaceae), the seeds ...
Dejean Alain - - 2005
This study was conducted on the reactions of Pheidole megacephala scouts when finding liquid food sources situated on territories marked by competing dominant ant species or on unmarked, control areas to see if the number of recruited nestmates is affected and if soldiers behave in ways adapted to the situation. ...
Preston Stephanie D - - 2005
Caching food is an economic, decision-making process that requires animals to take many factors into account, including the risk of pilferage. However, little is known about how food-storing animals determine the risk of pilferage. In this study, the authors examined the effect of a dominant competitor species on the caching ...
Bonaldo R M - - 2005
The banded butterflyfish (Chaetodon striatus) from the tropical and subtropical western Atlantic is a territorial, diurnal forager on benthic invertebrates. It is usually seen moving singly or in pairs, a few meters above the sea floor. We studied the foraging activity of C. striatus on rocky reefs in southeastern Brazil. ...
Daphna Gottlieb
We followed the daily and seasonal foraging patterns of the solitary bee Proxylocopa olivieri during two springs and summers in Har Gilo, Israel. During the foraging season, the bees exhibited a clear bimodal daily activity pattern. They foraged mostly before sunrise and after sunset. We hypothesized that this activity schedule ...
Alder Patricia - - 2005
We evaluated the effects of interspecific competition on ant bait performance with two urban pest ants, the Argentine ant, Linepithema humile (Mayr), and the little black ant, Monomorium minimum (Buckley). In a laboratory study, the impact of a solid sulfluramid bait on M. minimum was diminished when L. humile were ...
Clayton Nicola S - - 2005
Western scrub-jays (Aphelocoma californica) cached perishable and nonperishable food items, which they could recover after both short and long retention intervals. When perishable items were always degraded at recovery, jays decreased the number of perishable items cached and increased their caching of nonperishable items, relative to a control group whose ...
Sonnenburg Justin L - - 2005
Germ-free mice were maintained on polysaccharide-rich or simple-sugar diets and colonized for 10 days with an organism also found in human guts, Bacteroides thetaiotaomicron, followed by whole-genome transcriptional profiling of bacteria and mass spectrometry of cecal glycans. We found that these bacteria assembled on food particles and mucus, selectively induced ...
Yosef Reuven - - 2005
The impaling of prey is a behavioral trait restricted to the true shrikes (Laniidae). Here, we suggest the ontogeny of this behavior. We believe impaling originated from wedging behavior that occurs among several other groups of birds, including corvids. Accidental impaling during wedging was likely the behavioral precursor of purposeful ...
Mailleux Anne-Catherine - - 2005
In the ant Lasius niger, the ability to ingest their own desired volume is the key criterion that rules the recruiting behaviour of scouts. This volume acts as a threshold triggering the trail-laying response of foragers. In this paper, we show that this desired volume is specific to each individual ...
Randler Christoph - - 2005
Birds frequently interrupt feeding to scan their surrounding environment. Usually an inverse correlation between scan rate and flock size exists. The 'many-eyes' hypothesis suggests that more eyes are able to detect a predator earlier. Due to the 'dilution-effect' animals in larger groups experience 'safety in numbers', while the 'scramble competition' ...
Wägele Heike - - 2005
BACKGROUND: In general shell-less slugs are considered to be slimy animals with a rather dull appearance and a pest to garden plants. But marine slugs usually are beautifully coloured animals belonging to the less-known Opisthobranchia. They are characterized by a large array of interesting biological phenomena, usually related to foraging ...
Reid Rebecca A - - 2005
Rats were repeatedly exposed to an open arena containing two depletable food sources in a discrete-trials procedure. Their movement patterns were recorded and compared to adaptive foraging tactics such as minimizing distance or energy expenditure, thigmotaxis, and trail following. They were also compared to the predictions of the associative route-finder ...
Jarau Stefan - - 2005
Footprint secretions deposited at the nest entrance or on food sources are used for chemical communication by honey bees, bumble bees, and stingless bees. The question of the glandular origin of the substances involved, however, has not been unequivocally answered yet. We investigated the morphology and structure of tarsal glands ...
Soobramoney, Shernice; School of ...
Aspects of the foraging behaviour along an altitudinal gradient of four subpopulations Durban, Merrivale, Estcourt and Harrismith) of colour-banded Common Fiscals (<i>Lanius collaris</i>) were analysed in summer and winter in South Africa. The shrike subpopulations showed significant differences in their attack, capture and success rates. The shrikes obtained more food ...
Ahmad Al Ghamdi
Twenty indigenous (<I>Apis mellifera yemenitica</I>) honeybee colonies were transferred from the traditional log hives into modern movable frame (Langstroth) hives and divided into 4 Groups. Each group was provided with a modified frame to assess the effect of frame-type on colony settlement, wax secretion, sugar syrup and pollen consumption, sealed ...
Sommer, Frank
The foraging modes of calanoid copepods differ in that stationary suspension-feeding is more easily detected by prey with strong escape responses (ciliates) than is 'cruising' or 'ambushing' feeding. Thus, the ability of a copepod to include heterotrophic prey in its diet may be associated with its foraging mode and, further, ...
Villa Jos? D - - 2005
Worker honey bees from genetic strains selected for being resistant (R) or susceptible (S) to tracheal mites typically show large differences in infestation in field colonies and in bioassays that involve controlled exposure to infested bees. We used bioassays exposing newly emerged individuals to infested workers to compare the propensity ...
Le Boeuf Burney J - - 2005
BACKGROUND: The condition of many marine mammals varies with fluctuations in productivity and food supply in the ocean basin where they forage. Prey is impacted by physical environmental variables such as cyclic warming trends. The weaning weight of northern elephant seal pups, Mirounga angustirostris, being closely linked to maternal condition, ...
Elahi Robin - - 2005
The large predatory ant, Paraponera clavata, exerts measurable top-down effects in wet and moist Neotropical forests, and therefore its distribution has potential ecological implications. To determine how water affects the presence of this important predator, the ground nesting ecology of P. clavata was examined with respect to various habitat characteristics. ...
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