scholarly journals Species-Specific Traits Rather Than Resource Partitioning Mediate Diversity Effects on Resource Use

PLoS ONE ◽  
2009 ◽  
Vol 4 (10) ◽  
pp. e7423 ◽  
Author(s):  
Jasmin A. Godbold ◽  
Rutger Rosenberg ◽  
Martin Solan
Keyword(s):  
Resource Use ◽  
Resource Partitioning ◽  
Species Specific ◽  
Diversity Effects

scholarly journals Species–specific crab predation on the hydrozoan clinging jellyfish Gonionemus sp. (Cnidaria, Hydrozoa), subsequent crab mortality, and possible ecological consequences

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3966 ◽  
Author(s):  
Mary R. Carman ◽  
David W. Grunden ◽  
Annette F. Govindarajan
Keyword(s):  
Resource Use ◽  
Callinectes Sapidus ◽  
Trophic Interaction ◽  
Green Crab ◽  
Spider Crab ◽  
Crab Species ◽  
Negative Effect ◽  
Species Specific ◽  
Crab Predation ◽  
Density Treatment

Here we report a unique trophic interaction between the cryptogenic and sometimes highly toxic hydrozoan clinging jellyfish Gonionemus sp. and the spider crab Libinia dubia. We assessed species–specific predation on the Gonionemus medusae by crabs found in eelgrass meadows in Massachusetts, USA. The native spider crab species L. dubia consumed Gonionemus medusae, often enthusiastically, but the invasive green crab Carcinus maenus avoided consumption in all trials. One out of two blue crabs (Callinectes sapidus) also consumed Gonionemus, but this species was too rare in our study system to evaluate further. Libinia crabs could consume up to 30 jellyfish, which was the maximum jellyfish density treatment in our experiments, over a 24-hour period. Gonionemus consumption was associated with Libinia mortality. Spider crab mortality increased with Gonionemus consumption, and 100% of spider crabs tested died within 24 h of consuming jellyfish in our maximum jellyfish density containers. As the numbers of Gonionemus medusae used in our experiments likely underestimate the number of medusae that could be encountered by spider crabs over a 24-hour period in the field, we expect that Gonionemus may be having a negative effect on natural Libinia populations. Furthermore, given that Libinia overlaps in habitat and resource use with Carcinus, which avoids Gonionemus consumption, Carcinus populations could be indirectly benefiting from this unusual crab–jellyfish trophic relationship.

scholarly journals Resource use and coexistence of two syntopic hylid frogs (Anura, Hylidae)

2005 ◽  
Vol 22 (1) ◽  
pp. 61-72 ◽  
Author(s):  
Marcelo Menin ◽  
Denise de C. Rossa-Feres ◽  
Ariovaldo A. Giaretta
Keyword(s):  
Resource Use ◽  
Resource Partitioning ◽  
Niche Breadth ◽  
Reproductive Season ◽  
Seasonal Occurrence ◽  
Temporary Pond ◽  
Site Characteristics ◽  
Structural Differences ◽  
Time Periods

The objectives of this study were to measure and compare niche breadth and overlap of males of Hyla nana Boulenger, 1889 and Hyla sanborni Schmidt, 1944 in three neighboring ponds. The measured niche dimensions were seasonal occurrence, call site, and diet. The reproductive season of H. sanborni was longer in permanent ponds, whereas H. nana had a longer reproductive season in the temporary pond. Call site characteristics were similar for both species, however H. sanborni called from higher perches than H. nana. Diptera (Nematocera) were the most consumed item by both species in the three ponds but, in general, H. nana ingested larger prey than H. sanborni. For both species, the consumption of prey types was correlated with the availability in the environment. The multidimensional overlap between H. nana and H. sanborni was higher in the permanent ponds than the temporary pond, in which H. sanborni was rare. These species differed in abundance among ponds, consumed prey of different sizes, and probably fed in different time periods. Moreover, the data obtained suggest that structural differences in the ponds may modify the dynamics of resource partitioning between the two species. Beside the great overlap found in the major niche dimensions analyzed the detected differences may be great enough to allow their coexistence.

Resource partitioning within a browsing guild in a key habitat, the Chobe Riverfront, Botswana

2005 ◽  
Vol 21 (6) ◽  
pp. 641-649 ◽  
Author(s):  
Shimane W. Makhabu
Keyword(s):  
Plant Species ◽  
Resource Use ◽  
Resource Partitioning ◽  
Woody Species ◽  
Food Resources ◽  
Dry Season ◽  
Population Increase ◽  
Species Identity ◽  
Plant Parts ◽  
Elephant Population

Resource partitioning between elephant, giraffe, kudu and impala was assessed. This was to address concerns that elephant population increase adversely affects other species through depleting their food in key areas close to permanent water. Resources considered were woody species browsed, height browsed and plant parts browsed. Animals were observed as they browsed and the plant species, browsing heights and plant parts browsed were recorded. Observations were made over 1 y and the data were divided between wet and dry season. Schoener's index of resource use overlap was calculated for plant species, browsing heights and plant parts eaten and differences in overlap between wet and dry season were tested. Levin's measure of niche breadth in plant species utilized by the different browsers was calculated. Woody species identity was the main separator between food resources that elephant used and those giraffe, impala and kudu used. Giraffe, kudu and impala mainly browsed the same species and plant parts but browsed at different heights. There was no difference in resource use overlap between seasons with different resource availability. Since elephant browsed different woody species from those browsed by the others, it is unlikely that the increasing elephant population will deplete food resources for the other browsers.

Resource use within the crab-eating guild of the upper Kairezi River, Zimbabwe

1996 ◽  
Vol 12 (4) ◽  
pp. 475-490 ◽  
Author(s):  
James R. A. Butler ◽  
Brian E. Marshall
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Resource Use ◽  
Intraguild Predation ◽  
Aquatic Insects ◽  
Prey Item ◽  
Resource Partitioning ◽  
Food Resource ◽  
Dry Season ◽  
Invertebrate Drift

ABSTRACTCape clawless otters Aonyx capensis and African mottled eels Anguilla bengalensis were suspected of reducing numbers of rainbow trout Oncorhynchus mykiss in the upper Kairezi River, Zimbabwe, by preying on them and competing for the river crab Potamon perlatus. The analysis of otter, eel and trout diets showed that this is unlikely. Trout was an unimportant prey item for otters, none were found in the stomachs of 13 large eels, and any predation was probably minimised by the low densities of these predators. Some competition was probably present because crabs occurred in the diets of otters (relative occurrence 41.9%), eels (63.2%) and trout (7.4%), but it was impossible to quantify. Since these predators shared the crab food resource, the guild concept provided the basis for an analysis of their potential competitive relationships. Comparisons between the sizes of crabs selected and those available suggested that resource partitioning was occurring. Trout selected small crabs from the invertebrate drift, and because they were restricted by their mouth gapes. Otters and large eels ate larger, more abundant crab sizes; it is proposed that they instead partition resources spatially by feeding in separate micro-habitats. Intraguild predation by otters on eels may benefit trout by reducing competition for aquatic insects. Competition within the guild probably recedes in the dry season, when eels become inactive.

scholarly journals Multitrophic diversity effects depend on consumer specialization and species-specific growth and grazing rates

Oikos ◽  
2014 ◽  
Vol 123 (8) ◽  
pp. 912-922 ◽  
Author(s):  
Joanna Filip ◽  
Barbara Bauer ◽  
Helmut Hillebrand ◽  
Anna Beniermann ◽  
Ursula Gaedke ◽  
...  
Keyword(s):  
Specific Growth ◽  
Species Specific ◽  
Diversity Effects

FLORAL USE BY TWO SYMPATRIC BUMBLE BEE SPECIES (BOMBUS TERRICOLA AND BOMBUS TERNARIUS): EFFICIENCY CONSIDERATIONS

1998 ◽  
Vol 130 (5) ◽  
pp. 595-601 ◽  
Author(s):  
C.M.S. Plowright ◽  
R.C. Plowright
Keyword(s):  
Resource Use ◽  
Resource Partitioning ◽  
Bumble Bee ◽  
Asclepias Syriaca ◽  
Flower Density

AbstractThe purpose of this study was to explain a peculiarity of resource use by two sympatric bumble bee species. In one study area, pronounced resource partitioning was observed: Bombus terricola Kirby was confined to Asclepias syriaca L. and Bombus ternarius Say to Apocynum androsaemifolium L., and yet in another area both species frequented Apocynum. Measurements of floral characteristics and forager behaviour on Apocynum led to an hypothesis regarding floral use by two bumble bee species: B. terricola is relatively inefficient at flying between flowers, and so tends to visit Apocynum only in areas where the plants are closely spaced. Half of the patch of Apocynum was clipped so as to decrease flower density, with the expectation that, as a result, the frequency of B. terricola relative to B. ternarius would be reduced. The prediction was confirmed. The results underscore the role of context in floral use by bees.

Sign in / Sign up

Export Citation Format

Share Document