scholarly journals Neither large nor small: intermediate-sized food items for the cubs of the Patagonian gray fox (Pseudoalopex griseus)

1998 ◽  
Vol 76 (12) ◽  
pp. 2281-2284 ◽  
Author(s):  
Sonia C Zapata ◽  
Alejandro Travaini ◽  
Miguel Delibes
Keyword(s):  
Central Place ◽  
Foraging Theory ◽  
Central Place Foraging ◽  
Fecal Samples ◽  
Gray Fox ◽  
Food Items

According to central place foraging theory, adult Patagonian gray foxes (Pseudoalopex griseus) behaving efficiently should consume on the spot those food items too large to be carried and those too small to warrant being carried to the den. Consequently, fox cubs should be provisioned with intermediate-sized items. We tested this prediction by analyzing 96 fecal samples from adult foxes and 82 fecal samples from cubs belonging to three different dens collected near Junín de los Andes in the province of Neuquén, Argentina, from November 1994 to January 1995. As predicted, adult foxes consumed carrion of large ungulates (large items) and arthropods and berries (small items) significantly more often than cubs did. Cubs ate more intermediate-sized vertebrates, from lizards and birds to rodents and hares. Medium-sized armadillos, which are difficult to handle and transport, were consumed only by adults. Cubs ate some insects, which were probably captured by the cubs themselves near the den.

Tree Swallow selection for wetlands in agricultural landscapes predicted by central-place foraging theory

The Condor ◽  
2020 ◽  
Author(s):  
Andrew S Elgin ◽  
Robert G Clark ◽  
Christy A Morrissey
Keyword(s):  
Habitat Selection ◽  
Central Place ◽  
Foraging Theory ◽  
Agricultural Landscapes ◽  
Tree Swallow ◽  
Field Margins ◽  
Central Place Foraging ◽  
Prairie Pothole ◽  
Prairie Wetlands ◽  
Selection For

Abstract Millions of wetland basins, embedded in croplands and grasslands, are biodiversity hotspots in North America’s Prairie Pothole Region, but prairie wetlands continue to be degraded and drained, primarily for agricultural activities. Aerial insectivorous swallows are known to forage over water, but it is unclear whether swallows exhibit greater selection for wetlands relative to other habitats in croplands and grasslands. Central-place foraging theory suggests that habitat selectivity should increase with traveling distance from a central place, such that foragers compensate for traveling costs by selecting more profitable foraging habitat. Using global positioning system (GPS) tags, we evaluated habitat selection by female Tree Swallows (Tachycineta bicolor) at 4 sites containing wetlands and where terrestrial land cover was dominated by grasslands (grass, herbaceous cover) and/or cultivated cropland. We also used sweep-net transects to assess the abundance and biomass of flying insects in different habitats available to swallows (wetland pond margins, grassy field margins, and representative uplands). As expected for a central-place forager, GPS-tagged swallows selected more for wetland ponds (disproportionate to availability), and appeared to increasingly select for wetlands with increasing distance from their nests. On cropland-dominated sites, insect abundance and biomass tended to be higher in pond margins or grassy field margins compared to cropped uplands, while abundance and biomass were more uniform among sampled habitats at sites dominated by grass and herbaceous cover. Swallow habitat selection was not clearly explained by the distribution of sampled insects among habitats; however, traditional terrestrial sampling methods may not adequately reflect prey distribution and availability to aerially foraging swallows. Overall, our results underscore the importance of protecting and enhancing prairie wetlands and other non-crop habitats in agricultural landscapes, given their disproportionate use and capacity to support breeding swallow and insect populations.

An extensive study of the foraging ecology of beavers (Castor canadensis) in relation to habitat quality

2004 ◽  
Vol 82 (6) ◽  
pp. 922-933 ◽  
Author(s):  
D Gallant ◽  
C H Bérubé ◽  
E Tremblay ◽  
L Vasseur
Keyword(s):  
Habitat Quality ◽  
Foraging Behaviour ◽  
Foraging Ecology ◽  
Castor Canadensis ◽  
Central Place ◽  
Foraging Theory ◽  
Extensive Study ◽  
Food Items ◽  
Partial View ◽  
Selection Of

The objective of this study was to examine the foraging behaviour of the beaver (Castor canadensis Kuhl, 1820) and to explain its selection of terrestrial woody plant species according to central place foraging theory. Limitations in variety of food items in most studies with regard to size and (or) distance from the central place and information on availability of forage choices give a partial view of the subject. In this study, the theory is tested in a natural environment with high variability in food items with regard to these factors. Foraging choices by beavers were inspected by measuring variables on cut and uncut trees of every species encountered within 1 m of trail systems made by 25 beaver colonies in Kouchibouguac National Park in New Brunswick, Canada, thereby quantifying the availability of the different food items. The effect of habitat quality (food availability) on the foraging behaviour of beavers was also tested. The results of this study suggest that with increasing distance from the pond, beavers in high-quality habitats selected fewer, but larger, trees and are more species selective. This selectivity was diminished in habitats of lower quality. The results of this study are consistent with the predictions of the central foraging theory.

Testing assumptions of central place foraging theory: a study of Adélie penguins Pygoscelis adeliae in the Ross Sea

2014 ◽  
Vol 46 (2) ◽  
pp. 193-205 ◽  
Author(s):  
R. Glenn Ford ◽  
David G. Ainley ◽  
Amelie Lescroël ◽  
Phil O'B. Lyver ◽  
Viola Toniolo ◽  
...  
Keyword(s):  
Ross Sea ◽  
Central Place ◽  
Foraging Theory ◽  
Central Place Foraging ◽  
Pygoscelis Adeliae ◽  
Adélie Penguins

Central-place foraging in nursing, arthropod-gleaning bats

2008 ◽  
Vol 86 (7) ◽  
pp. 623-626 ◽  
Author(s):  
Shai Daniel ◽  
Carmi Korine ◽  
Berry Pinshow
Keyword(s):  
Central Place ◽  
Foraging Theory ◽  
Central Place Foraging ◽  
Trade Off ◽  
Positive Correlation ◽  
Bout Length ◽  
Foraging Area ◽  
Data Support ◽  
Foraging Site ◽  
Foraging Time

Central-place (CP) foraging theory predicts a positive correlation between the time a breeding CP forager spends in a patch and the distance of the patch to the CP. We found that nursing female Hemprich’s long-eared bats ( Otonycteris hemprichii Peters, 1859; Vespertilionidae) that forage around a lake in the Negev roost in only two areas: one 0.5–2 km (near) and one 9 km (far) from the foraging area. If these bats are CP foragers, then the strategies of the two groups should differ. We predicted that females roosting farther away would have longer but fewer foraging bouts. Using radiotelemetry, we measured the activity of six females from the near site and three from the far site. Without exception, females from the far site made a single, prolonged foraging bout each night, while females roosting nearby made several shorter bouts. Among the females from the near site, daily foraging time, mean daily foraging bout length, and first daily foraging bout length were all significantly and positively correlated with distance between the roost and the foraging site. Our data support the prediction that female O. hemprichii are CP foragers. We suggest that the females trade off using a safe roost site, distant from a choice foraging area, and lower nursing frequency against using a risky roost site close to the foraging area and greater nursing frequency.

Food choice by Messor arenarius ants in different distances from their nest: testing increased selectivity theory

2020 ◽  
pp. 1-6
Author(s):  
Ittai Warburg
Keyword(s):  
Food Choice ◽  
Nutritional Value ◽  
Central Place ◽  
Nest Entrance ◽  
Central Place Foraging ◽  
Distance Range ◽  
Food Items ◽  
Whole Wheat ◽  
Food Site ◽  
Wheat Seeds

Abstract According to central-place-foraging theory, selectivity of central-place foragers to larger or more profitable food items should increase as the distance from their nest to the food increases. In this research it was checked, if the selectivity of ants of the species Messor arenarius (Fabricius) to larger food items increases as a function of the distance from their nest entrance to the food site. In food choice experiments, whole wheat seeds and halves of wheat seeds cut longitudinally were offered to M. arenarius ants at the same points. These ants preferred halves of wheat seeds cut longitudinally over whole wheat seeds, in all the distances from nest entrance that were checked in this research - 1m, 5m or 10m from nest entrance. According to these findings, M. arenarius ants did not show increased selectivity to different wheat particles within a distance range of 1m – 10m from their nest entrance. It is possible that since the nutritional value of wheat is relatively high, these ants could not evaluate the nutritional value of wheat particles that were offered to them.

Population and Community Consequences of Spatial Subsidies Derived from Central-Place Foraging

2007 ◽  
Vol 170 (6) ◽  
pp. 902
Author(s):  
Fagan ◽  
Frithjof Lutscher ◽  
Katie Schneider
Keyword(s):  
Central Place ◽  
Central Place Foraging ◽  
Spatial Subsidies
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