A biologically explicit simulation model of resource competition between two species of seed-eating heteromyid rodent indicates that stable coexistence is possible on a homogeneous resource if harvested food is stored and consumers steal each other's caches. Here we explore the coexistence mechanisms involved by analyzing how consumer phenotypes and presence ...

The distance that mammalian herbivores can travel without interrupting food processing corresponds to a distance threshold (d*) in plant spacing where change occurs in the mechanisms regulating the functional response. The instantaneous rate of food consumption is controlled by food encounter rate when plant spacing exceeds d*. Below this threshold, ...

In hierarchical patch systems, small-scale patches of high density are nested within large-scale patches of low density. The organization of multiple-scale hierarchical systems makes non-random strategies for dispersal and movement particularly important. Here, we apply a new method based on first-passage time on the pathway of a foraging seabird, the ...

At present there is no consensus theory explaining the evolutionary stability of mutualistic interactions. However, the question is whether there are general 'rules', or whether each particular mutualism needs a unique explanation. Here, I address the ultimate evolutionary stability of the 'agricultural' mutualism between fungus-growing termites and Termitomyces fungi, and ...

If food pilferage has been a reliable selection pressure on food caching animals, those animals should have evolved the ability to protect their caches from pilferers. Evidence that animals protect their caches would support the argument that pilferage has been an important adaptive challenge. We observed naturally caching Eastern grey ...

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 ...

The role of habitat complexity in the coexistence of ant species is poorly understood. Here, we examine the influence of habitat complexity on coexistence patterns in ant communities of the remote Pacific atoll of Tokelau. The invasive yellow crazy ant, Anoplolepis gracilipes (Smith), exists in high densities on Tokelau, but ...

We review the evidence for behavioral avoidance of plant secondary metabolites (PSMs) and identify how, and the circumstances under which it occurs. Behavioral strategies of avoidance of PSM can only be fully understood in relation to the underlying physiological processes or constraints. There is considerable evidence that animals learn to ...

We review the evidence for behavioral avoidance of plant secondary metabolites (PSMs) and identify how, and the circumstances under which it occurs. Behavioral strategies of avoidance of PSM can only be fully understood in relation to the underlying physiological processes or constraints. There is considerable evidence that animals learn to ...

Western scrub-jays (Aphelocoma californica) hide food caches for future consumption, steal others' caches, and engage in tactics to minimize the chance that their own caches will be stolen. We show that scrub-jays remember which individual watched them during particular caching events and alter their recaching behavior accordingly. We found no ...

At Latham Island, Tanzania, in August 2004 and December 2005, flying fish (Exocoetidae) contributed 90% by mass of prey items regurgitated by masked boobies Sula dactylatra. The fish had a mean caudal length of 164mm. Two boobies generally foraged in deep water, away from the Tanzanian coastline, ranging up to ...

My thesis examines the evolutionary significance of polydomy using the ant Iridomyrmex purpureus as a model species. In polydomous colonies, several nests are separated spatially, but connected socially by the interchange of workers, brood and food. The nature of interactions among ants from different nests of a polydomous colony varies ...

1. The effect of competition for a limiting resource on the population dynamics of competitors is usually assumed to operate directly through starvation, yet may also affect survival indirectly through behaviourally mediated effects that affect risk of predation. Thus, competition can affect more than two trophic levels, and we aim ...

Besides the "normal" challenge of obtaining adequate intake rates in a patchy and dangerous world, shorebirds foraging in intertidal habitats face additional environmental hurdles. The tide forces them to commute between a roosting site and feeding grounds, twice a day. Moreover, because intertidal food patches are not all available at ...

If the food distribution contains spatial pattern, the food density in a particular patch provides a forager with information about nearby patches. Foragers might use this information to exploit patchily distributed resources profitably. We model the decision on how far to move to the next patch in linear environments with ...

The natural diet of the Rosy-faced Lovebird in the wild was investigated from January–August 2004, at three Namibian locations: Claratal, Hohewarte and Haris. Foraging patterns, habitat use, daily feeding activities and preferred dietary species were investigated. The lovebirds fed on food items from at least 19 species, which included seeds, ...

Dawson's burrowing bee is a large, fast-flying solitary nesting bee endemic to the arid zone of Western Australia. In this study the population structure of the species was examined with molecular markers. Using eight microsatellite loci, we genotyped 531 adult female bees collected from 13 populations of Dawson's burrowing bee, ...

Foraging behavior was evaluated in honeybees trained to fly to a feeder containing sucrose only, 1% ethanol, 5% ethanol, or 10% ethanol. The results indicated that exposure to ethanol disrupted several types of honeybee social behavior within the hive. Consumption of ethanol at the feeding site reduced waggle dance activity ...

An element common to the recruitment communication of eusocial bees (honey bees, stingless bees and bumble bees) are pulsed thorax vibrations generated by successful foragers within the nest. In stingless bees, foragers vibrate during the unloading of the collected food. In the present study on Melipona seminigra we demonstrate that ...

The effect of fipronil-treated sand on digging behavior and mortality of red imported fire ant, Solenopsis invicta Buren, workers was examined in the laboratory. No-choice digging bioassays where fipronil-treated sand was the only available digging substrate were conducted on two colonies at fipronil concentrations of 0.00, 0.05, 0.10, 0.50, 1.00, ...

A preliminary study of ants and other free-living arthropods which visited bracken at a post-fire stand was conducted. Eight species of ants visited bracken at the post-fire stand, one month after forest fire. In contrast, only one species visited bracken at the fire-free stand. Ants and other arthropods which visited ...

Animals often face complex and changing food environments. While such environments are challenging, an animal should make an association between a food type and its properties (such as the presence of a nutrient or toxin). We use information theory concepts, such as mutual information, to establish a theory for the ...

The search for and ingestion of food are essential to all animals, which spend most of their lives looking for nutritional sources, more than other activities such as mating, intra-specific disputes or escaping from predators. The present study aims to describe and quantify several aspects of foraging behavior, diet and ...

Peanut skins are a low-value byproduct of peanut processing operations. They have been found to contain significant levels of natural antioxidants, but their antioxidant activity in muscle foods is unknown. The effects of peanut skin extracts on oxidation (TBARS) and color (CIE L(∗)a(∗)b(∗)) was studied in ground beef and ground ...

Domestic dogs (Canis familiaris) and great apes from the genus Pan were tested on a series of object choice tasks. In each task, the location of hidden food was indicated for subjects by some kind of communicative, behavioral, or physical cue. On the basis of differences in the ecologies of ...

Monomorium orientale Mayr (Hymenoptera: Formicidae) is a common structure- and food-infesting ant in Asia. There is only limited information on the biology and habits of this species, especially on the preferred foods and distribution of nutrients in colonies. We conducted a laboratory study on the distribution of carbohydrates, proteins, and ...

Apis mellifera bees perform dances to communicate the presence of desirable nectar sources. The regulation of these dances does not depend exclusively on properties of the nectar sources, but also upon certain stimuli derived from the foraging status of the colony as a whole; i.e. bees exploiting a source of ...

The fungus-growing termites Macrotermes cultivate the obligate ectosymbiontic fungi, Termitomyces. While their relationship has been extesively studied, little is known about the gut bacterial symbionts, which also presumably play a crucial role for the nutrition of the termite host. In this study, we investigated the bacterial gut microbiota in two ...

The ant Temnothorax albipennis uses a technique known as tandem running to lead another ant from the nest to food--with signals between the two ants controlling both the speed and course of the run. Here we analyse the results of this communication and show that tandem running is an example ...

The bark of trees is an important foraging substrate for a range of vertebrate insectivores. This study aimed to investigate the distribution of food resources available to the bark-foraging insectivore "Phascogale tapoatafa", and to compare prey biomass on bark versus the litter layer. We conducted nocturnal sampling for arthropods on ...

Nectar of many bee flowers contains secondary compounds, which are considered toxic for honeybees on repeated exposure. Although many anecdotal reports indicate the toxicity of secondary compounds to bees, only a few studies have tested the extent of toxicity at different honeybee ages, especially at the larval stages. Honeybees encounter ...

Temporal and geographic variability in adult body size can be a useful indicator of a population's adaptation. The southern African Cape supported foraging populations exclusively until some pastoralism is seen, ca. 2000 BP. This paper describes and interprets body-size patterns among foragers, as deduced from maximum femoral lengths and femoral ...

An experiment was carried out at Alemaya University in Ethiopia to investigate the effect of night kraaling on the dry matter intake (DMI), live weight gain (LWG) and foraging behaviour of Ogaden cattle. Three groups of four animals were given either 7 h access to pasture per day, simulating traditional ...

This study tested 3 food enrichment items mentioned in a laboratory primate newsletter with 6 adult Eulemur macaco and 3 adult Lemur catta to examine whether the items would affect the behavior of the lemurs. The results suggest that Food Enrichment Item 3 (a wire box filled with whole grapes, ...

Strips coated with conidia of Metarhizium anisopliae (Metschinkoff; Deuteromycetes: Hyphomycetes) to control the parasitic mite, Varroa destructor (Anderson and Trueman) in colonies of honey bees, Apis mellifera (Hymenoptera: Apidae) were compared against the miticide, tau-fluvalinate (Apistan) in field trials in Texas and Florida (USA). Apistan and the fungal treatments resulted ...

Hoarding is a species-typical behavior shown by rodents, as well as other animals. By hoarding, the rodent secures a food supply for times of emergency (for example, when threatened by a predator) or for times of seasonal adversity such as winter. Scatter hoarding, as seen typically in squirrels and birds, ...

BACKGROUND: Social insects show considerable variability not only in social organisation but also in the temporal pattern of nest cycles. In annual eusocial sweat bees, nest cycles typically consist of a sequence of distinct phases of activity (queen or workers collect food, construct, and provision brood cells) and inactivity (nest ...

Changes in animal population size are driven by the interactions between intrinsic processes and extrinsic forces, and identifying the proximate mechanisms behind population change remains a fundamental question in ecology. Here we report on how measuring behavioural and state proxies of food availability among populations experiencing different growth rates can ...

Physiological states such as reproductive stage, parasite load, body condition, and environmental conditions, influence behaviours in complex ways. According to the Clark's asset-protection principle (Clark, 1994. Behav Ecol 5:159-170), individuals in good body condition take fewer predation risks than conspecifics in lesser condition. In many ectotherms, foraging, digestion, and moulting ...

Because workers in the eusocial Hymenoptera are more closely related to sisters than to brothers, theory predicts that natural selection should act on them to bias (change) sex allocation to favor reproductive females over males. However, selection should also act on queens to prevent worker bias. We use a simulation ...

Honey bee, Apis mellifera L. (Hymenoptera: Apidae), colonies infested by parasitic mites are more prone to suffer from a variety of stresses, including cold temperature. We evaluated the overwintering ability of candidate breeder lines of Russian honey bees, most of which are resistant to both Varroa destructor Anderson & Trueman ...

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 ...

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 ...

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 ...

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 ...

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. ...

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 ...

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 ...

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 ...

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 ...