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1

Risk-taking and foraging strategy in honey bee workers collecting nectar and water

100%
Woyciechowski M.
Pszczelnicze Zeszyty Naukowe
|
1998
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tom 42
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nr 2
2

Home range and activity of the Indian giant flying squirrel (Petaurista philippensis) in Taiwan: influence of diet, temperature, and rainfall

84%
Acta Theriologica
|
2012
|
tom 57
|
nr 3
Knowledge on home range and activity patterns, along with their responses to environmental fluctuations, is important for the understanding of wildlife ecology and conservation, but related studies on giant flying squirrel species (genus Petaurista) are still limited. We radio-tracked five Indian giant flying squirrels (Petaurista philippensis) in subtropical Taiwan to assess their home range and activity patterns, as well as their behavioral strategy to cope with fluctuations in food quality. Specifically, we assessed the travelling and resting times of P. philippensis in relation to its energy requirements during periods of low food quality in winter. The influence of temperature and rainfall was also investigated. A total of five individuals were radio-tracked for 1–6 months. The home ranges of four individuals averaged 2.8 ± 2.0 ha (± SD), based on the 95 % kernel method. Mean home ranges of two adult males (4.4 ± 1.3 ha) were larger than a female (1.8) and sub-adult male (0.8). P. philippensis was found to be more active around dusk and dawn and less active at midnight. Daily ranging distance and activities were negatively associated with proportion of mature leaves in diet of the only female that we tracked. Rainfall had negative effects on activities of the males, while temperature had no significant influence. The current study suggested an energy conservative strategy of P. philippensis. Home ranges of P. philippensis are smaller than those of smaller flying squirrel species (genus Glaucomys and Pteromys spp.), which may be related to the differences in food habits and gliding efficiency.
3

Foods of the northern myotis, Myotis septentrionalis, from Missouri and Indiana, with notes on foraging

84%
Brack,Jr. V., Whitaker,Jr. J. O.
Acta Chiropterologica
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2001
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tom 03
|
nr 2
This paper presents information on foods eaten by the northern myotis, Myotis septentrionalis, from four different localities in the states of Missouri and Indiana, USA. Based on fecal and stomach content analyses, we found that M. septentrionalis feeds heavily on Lepidoptera (10.4-94.0% of the volume), and to a lesser extent on Coleoptera (0.4-64.0), Trichoptera (0.0-54.5), and Diptera (0.0-15.3). Non-flying prey items, such as spiders and lepidopterous larvae, made up 12.7% of food in 63 stomachs from Copperhead Cave, Indiana, which is a clear indication of the gleaning behavior of this species. Foraging was concentrated in the understory of non-riparian habitat, which may be a further reflection of a gleaning strategy. No significant differences were found in the overall diet of M. septentrionalis between evening and morning feeding periods, although there were some differences in consumption of particular orders.
4

Diet of the raccoon dog Nyctereutes procyonoides - a canid with an opportunistic foraging strategy

84%
Sutor A., Kauhala K., Ansorge H.
Acta Theriologica
|
2010
|
tom 55
|
nr 2
165-176
We examined the raccoon dog’s Nyctereutes procyonoides (Gray, 1834) diet in two agricultural landscapes of Germany and compared these results with other diet studies from its native and introduced ranges. The diet composition was influenced as well by the landscape structures as by the seasons: in the waterrich study area 2 amphibians (54.1%) and fish (10.8%) occurred more frequently in the samples. In study area 1 amphibians (19.0%) and invertebrates (69.4%) gained more significance in the diet in summer, whereas in winter samples maize (32.8%) was an important food item. The diet composition shifted according to the availability of different food items. Raccoon dogs, ability to feed temporarily on one food source may possibly cause a serious problem to endangered small populations of birds and amphibians. The review of 81 data sets from nine countries showed that seasons and locality affected the occurrence of most food items. However, comparable to the present study, small mammals, insects and plants were identified as important food items both in native and introduced ranges of the raccoon dog. In regard to its diet composition, gathering foraging strategy and inactivity during winter, the raccoon dog probably preys less often on game animals and birds than the native red fox Vulpes vulpes.
5

Foraging strategy of plateau zokors (Eospalax baileyi Thomas) when collecting food for winter caches

84%
Xie J.-X., Lin G.-H., Zhang T.-Z., Su J. P.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 1
Subterranean life style is characterized by limited food resource and energy consuming burrow behavior. Subterranean rodents are usually recognized as dietary generalists. In the current study, we investigated the species composition of winter caches of plateau zokors (Eospalax baileyi), and the dissimilarity of species composition in caches and in the vicinity of the burrows. We have made our research in Kobresia dominated vegetation at the altitude 3200 m a.s.l. We used the non-parametric method to test the similarities between the relative dry mass of the plant species within caches and their closed vicinity. This method was based on measures of distance between pairs of individual multivariate observations. Our results revealed that although plateau zokors cached most (60) of the plant species found in the vicinity of their burrow systems (66), the cached dry mass was dominated by a few species. Nine plant species accounted for 80% dry mass of plants present in zokors’ caches, Polygonum viviparum (50%) and other perennial poisonous forbs constitute 70% dry mass of the caches. Results showed that the dissimilarity between the relative dry mass of plant species within caches and in their vicinity was extremely significant (for Bray-Curtis distance measure, R = 0.355, P = 0.000; for Euclidean distance measure R =0.319, P =0.000). These results showed that plateau zokors don’t forage randomly when collecting food for winter caches. We suppose that rather than using a non-selective foraging strategy by dealing with high fiber-content plants, plateau zokors have forged another dietary strategy to meet the energy demands in the evolutionary process: to deal with poisonous forbs.
6

Competition between Formica cinerea Mayr [Hymenoptera: Formicidae] and co-occurring ant species, with special reference to Formica rufa L.: direct and indirect interferences

84%
Czechowski W., Marko B.
Polish Journal of Ecology
|
2005
|
tom 53
|
nr 4
Formica cinerea Mayr is supposed to be the top dominant of ant communities in successional sandy habitats, whereas wood ant species, e.g. F. rufa L., play this role in forests. These species often co-occur in overlapping habitats. The aim of the study was to recognize competitive interrelations between them in the broad ecological aspect of relations with local subordinate species, including F. fusca L., Tetramorium caespitum (L.) and Myrmica schencki Viereck. Study area was a sand dune slope surrounded by pine forest at Tvärminne, S Finland, where F. cinerea nest complexes were encircled by F. rufa colonies. Baiting experiments, preceded by ‘nudum’ observations were carried out. The presumption that F. rufa would influence the activity of F. cinerea was not supported by the results. No-ant zones separated the territories of these two species almost through the total length of the boundary of the F. cinerea range. The outcome of interspecific interactions within the multi-species community studied corresponded with the species competitive status generally. The results are discussed in the context of interspecific competition hierarchy in ants and succession of ant communities.
7

Biodiversity and energy transfer to top trophic levels in two contrasting Arctic fjords

67%
Weslawski J. M., Kwasniewski S., Stempniewicz L., Blachowiak-Samolyk K.
Polish Polar Research
|
2006
|
tom 27
|
nr 3
259-278
The food and foraging strategy of fifteen species of seabirds and sea mammals from two high Arctic fjords were analysed. One of the fjords, Kongsfjord, is strongly influenced by warm waters from the Atlantic, while Hornsund is of a more Arctic character. Prey species in the Atlantic waters were more diverse (82 species and 16 functional groups) compared to those of Arctic waters (67 prey species and 14 functional groups). The consumption of top predators from Hornsund in the peak season of July was estimated at 2.86*106 MJ, while that in Kongsfjord was 1.35*106 MJ. For the analysed function of the ecosystem (the transfer of energy to the top trophic levels) the specific character of prey species is of key importance and not the diversity, abundance or biomass per se. Lower species diversity and biomass in Arctic waters is compensated for by the occurrence of larger individuals of these species, which permits top predators to prey directly on lower trophic levels.
8

Food habits of Orii’s flying-fox, Pteropus dasymallus inopinatus, in relation to food availability in an urban area of Okinawa-jima Island, the Ryukyu Archipelago, Japan

67%
Nakamoto A., Kinjo K., Izawa M.
Acta Chiropterologica
|
2007
|
tom 09
|
nr 1
The diet of the Orii's flying-fox, Pteropus dasymallus inopinatus, a subspecies of the Ryukyu flying-fox, was investigated on Okinawa-jima Island, Japan. The Orii's flying-fox is a generalist forager that feeds on 78 plant species from 62 genera and 43 families. They consume fruits of 53 species, flowers of 20 species, and leaves of 18 species. Cultivated or naturalized plants composed almost half of the diet. Diversity in the diet may be an adaptation to unstable food conditions on this small subtropical island. The number of individual Orii's flying-foxes fluctuated greatly corresponding to monthly changes in food availability, especially that of Ficus microcarpa, which was the animal's main food resource throughout the year. Orii's flying-foxes may adapt to an urban environment by intensively using areas with abundant planted trees.
9

The influence of nest placement on breeding success of the Blackcap (Sylvia atricapilla L.) in two different forest habitats

67%
Zielinski J.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 2
One of the hypotheses to explain a lack of relationship between nest location and breeding success of passerine birds predicts that in an environment characterized by a high diversity of predators that use a variety of foraging strategies, clutches in different locations and degrees of concealment may be equally subject to destruction. In this study I assumed that the impact of nest location on breeding success of the Blackcap Sylvia atricapilla would differ in habitats characterized by significantly different species richness and, consequently, population density and species diversity of potential predators. Thus, I expected that the influence of the nest location and particularly its concealment on breeding success of the Blackcap would be more significant in a habitat characterized by the overall low biotic diversity and low vegetation density. The study was conducted in two forested areas located in central Poland – managed pine forest characterized by low biodiversity and vegetation density and floodplain forest consisting of much higher biodiversity and having higher stand density. I assessed the influence of Blackcap nest placement (concealment, height above the ground, nest plant height, distance from the nest to the closest edge of the nest plant) on breeding success. Among the analyzed parameters, only nest concealment had a significant impact on breeding success. This conclusion, however, pertains only to the pine forest, where successful nests were better concealed than nests with clutch losses. Similar relationships were found in the floodplain forest area, but they were not statistically significant.
10

Foraging strategies and dietary preferences of a high mountain ant. [Hymenoptera: Formicidae]

67%
Fernandez-Escudero I., Tinaut A.
Polish Journal of Ecology
|
1998
|
tom 46
|
nr 1
11

Diet of a Piedmont population of Ctenomys mendocinus [Rodentia, Ctenomyidae]: seasonal patterns and variations according sex and relative age

67%
Puig S., Rosi M. I., Cona M. I., Roig V. G., Monge S. A.
Acta Theriologica
|
1999
|
tom 44
|
nr 1
Dietary composition was determined seasonally in males and females of Ctenomys mendocinus Philippi, 1869 from the Andean Piedmont (Mendoza, Argentina) during the reproductive and non-reproductive period. Reproductive condition and relative age of each animal was determined. Stomach contents were individually analyzed with the microhistological technique, Dietary generalism is supported by the high propor­tion of available genera eaten, but the intensity and continuity of use suggested specialization on grasses. Prédation risk induces minimization of the exposure time out of the burrow, and could justify the specialization in grasses, considering that other rodents showed lower harvest and handling times for grasses than for shrubs. Males had a more varied diet than females in winter, and the opposite occurred in spring. Since males have been found to dig longer burrow systems than females in winter, searching for mates might cause males to intersect a higher number of food items during that season. Higher energetic and nutritional requirements associated with pregnancy and nursing may lead to the inclusion of more food items in the spring diet of females, and their higher specialization on grasses. Dietary similarities between immature and mature individuals suggested that age did not affect selection of diet items. Seasonal variation in dietary diversity suggested a foraging strategy adaptive to environmental seasonal variations and to the subterranean life style.
12

Lasius psammophilus Seifert and Formica cinerea Mayr [Hymenoptera: Formicidae] on sand dunes: conflicts and coexistence

67%
Marko B., Czechowski W.
Annales Zoologici
|
2004
|
tom 54
|
nr 2
Lasius psammophilus Seifert and Formica cinerea Mayr can both be found on sand dunes in high densities. Sometimes they even nest in each other's immediate neighbourhood, which implies the possibility of conflicts, and the existence of mechanisms for avoiding contest competition. In such case an appropriate method is the analysis of the distribution and behaviour of foraging individuals around their colonies in the absence and in the presence of baits. The results show that the higher foraging activity of L. psammophilus with lower temperature and higher humidity as compared to F. cinerea, as well as the lack of spatial interference assures a relatively peaceful coexistence even in the case of neighbouring colonies. While L. psammophilus is characterized by fortuitousness regarding the chances of discovering food sources, F. cinerea foragers search more thoroughly around their colonies. Conflicts can arise over large food sources, which conflicts are usually won by F. cinerea. However, the more efficient recruitment system of L. psammophilus (earlier start and higher intensity), allows this species dominate at clumped food patches when the climatic conditions are favourable. The possible ways of coexistence are discussed, as well as the species' positions in the competition hierarchy.
13
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A dental microwear texture analysis of the Mio-Pliocene hyaenids from Langebaanweg, South Africa

59%
Stynder D. D., Ungar P. S., Scott J. R., Schubert B. W.
Acta Palaeontologica Polonica
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2012
|
tom 57
|
nr 3
Hyaenids reached their peak diversity during the Mio−Pliocene, when an array of carnivorous species emerged alongside dwindling civet−like and mongoose−like insectivorous/omnivorous taxa. Significantly, bone−cracking morphological adaptations were poorly developed in these newly−emerged species. This, their general canid−like morphology, and the absence/rarity of canids in Eurasia and Africa at the time, has led researchers to hypothesise that these carnivorous Mio−Pliocene hyaenas were ecological vicars to modern canids. To shed further light on their diets and foraging strategies, we examine and compare the dental microwear textures of Hyaenictitherium namaquensis, Ikelohyaena abronia, Chasmaporthetes australis, and Hyaenictis hendeyi from the South African Mio−Pliocene site of Langebaanweg with those of the extant feliforms Crocuta crocuta, Acinonyx jubatus, and Panthera leo (caniforms are not included because homologous wear facets are not directly comparable between the suborders). Sample sizes for individual fossil species are small, which limits confidence in assessments of variation between the extinct taxa; however, these Mio−Pliocene hyaenas exhibit surface complexity and textural fill volume values that are considerably lower than those exhibited by the living hyaena, Crocuta crocuta. Dental microwear texture analysis thus supports interpretations of craniodental evidence suggesting low bone consumption in carnivorous Mio−Pliocene hyaenas.
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