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Determinants of Habitat Selection by Hatchling Australian Freshwater Crocodiles  [PDF]
Ruchira Somaweera, Jonathan K. Webb, Richard Shine
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0028533
Abstract: Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle), most hatchling (<12-month-old) freshwater crocodiles (Crocodylus johnstoni) are found in floating vegetation mats or grassy banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles) were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk.
Foraging Habitat Preferences of Herons and Egrets  [cached]
Choi, Yu-Seong,In-Ki Kwon,Jeong-Chil Yoo
Journal of Ecology and Field Biology , 2007,
Abstract: We investigated the foraging habitat preferences of herons and egrets in an agricultural area inAsan city, Chungcheongnam-do, Korea. In the study area, rice fields were the most abundant habitat type (86.8%)and total suitable feeding habitat was greater in the northern area (59.0%) than the southern area (22.5%) ofthe colony. Most feeding herons and egrets were located in the northern area of the colony. The number offeeding individuals in a given area was related to the available feeding area (Pearson correlation, r=0.773,p<0.001 for field habitats; r=0.901, p<0.001 for freshwater habitats). Feeding habitat preferences differed amongspecies. Grey herons (Ardea cinerea), great egrets (Egretta alba), and black-crowned night herons (Nycticoraxnycticorax) used reservoirs and ditches. However, intermediate egrets (E. intermedia) and cattle egrets (Bubulcusibis) were dependent on rice fields. The little egret (E. garzetta) was a habitat generalist using all types ofhabitats. The two largest species, grey herons and great egrets, fed at deeper site than little egrets and foragedin deeper sites in reservoirs than in ditches (χ2-test, χ23=26.6 and p<0.001 for grey herons, χ23 =17.5 andp<0.001 for great egrets). All species displayed seasonal changes in feeding habitat use and these changes wererelated with changes in availability of feeding habitats.
Classification is instructive – comments on a published table of antelope habitat preferences  [cached]
B.J Coetzee
Koedoe : African Protected Area Conservation and Science , 1980, DOI: 10.4102/koedoe.v23i1.633
Abstract: Pienaar (1974) showed the habitat preferences of South African antelope species in a two-way table. Rows represent species and columns represent habitats. Matrix entries link species to their preferred habitats (Table 1). Species in Table 1 are in taxonomic order, which has no apparent bearing on their habitat preferences.
The habitat preferences of fishes from the Limpopo river system, Transvaal and Mocambique
I.G. Gaigher
Koedoe : African Protected Area Conservation and Science , 1973, DOI: 10.4102/koedoe.v16i1.888
Abstract: The species composition of fishes in the Limpopo River system is described. The frequency of occurrence for eachhabitat type is expressed as a percentage of the habitats sampled. A check list of species is presented and the species can be grouped into five habitat preferences.
The Impact of Human Encroachment and River Bank Agricultural Activities on the Habitat of the Manatee (Trichechus Senegalensis) Along the Lower Benue River, Benue State, Nigeria
PO Egwumah, IM Iwar, OW Okibe
Journal of Research in Forestry, Wildlife and Environment , 2009,
Abstract: The impact of human encroachment and river bank Agricultural activities on the habitat of the manatee (Trichechus Senegalensis) was investigated. The method of data collection involved the use of a structured questionnaire administered to farmers and fishermen. Vegetation survey in three selected sites along the river was carried out during the dry and raining seasons and crops cultivated during these seasons were identified. Chemicals used by farmers, measurement of settlements and farms from the river bank as well as the population trends in the selected zones were investigated. The result was subjected to descriptive and inferential statistics. Nine different vegetable crops were cultivated in Makurdi over an area of 16.974 ha, while 3 crops were cultivated in Abinsi (11.2076 ha) and 2 in Gbajimba (6.8775 ha). Plant diversity in Makurdi during the dry season is (0.1322), Abinsi (0.795) and Gbajimba (0.0568) while Abinsi had a diversity of 0.3281 Makurdi 0.2524 and Gbajimba 0.1749, during the raining season. Correlation coefficient (r) shows a significant relationship (p>0.05) between plants during the dry and rainy period in all the three zones. There is massive use of chemicals during the dry season farming while there is an increased activity of sharp sand collection along the river.
Winter Habitat Preferences for Florida Manatees and Vulnerability to Cold  [PDF]
David W. Laist, Cynthia Taylor, John E. Reynolds
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0058978
Abstract: To survive cold winter periods most, if not all, Florida manatees rely on warm-water refuges in the southern two-thirds of the Florida peninsula. Most refuges are either warm-water discharges from power plant and natural springs, or passive thermal basins that temporarily trap relatively warm water for a week or more. Strong fidelity to one or more refuges has created four relatively discrete Florida manatee subpopulations. Using statewide winter counts of manatees from 1999 to 2011, we provide the first attempt to quantify the proportion of animals using the three principal refuge types (power plants, springs, and passive thermal basins) statewide and for each subpopulation. Statewide across all years, 48.5% of all manatees were counted at power plant outfalls, 17.5% at natural springs, and 34.9 % at passive thermal basins or sites with no known warm-water features. Atlantic Coast and Southwest Florida subpopulations comprised 82.2% of all manatees counted (45.6% and 36.6%, respectively) with each subpopulation relying principally on power plants (66.6% and 47.4%, respectively). The upper St. Johns River and Northwest Florida subpopulations comprised 17.8% of all manatees counted with almost all animals relying entirely on springs (99.2% and 88.6% of those subpopulations, respectively). A record high count of 5,076 manatees in January 2010 revealed minimum sizes for the four subpopulations of: 230 manatees in the upper St. Johns River; 2,548 on the Atlantic Coast; 645 in Northwest Florida; and 1,774 in Southwest Florida. Based on a comparison of carcass recovery locations for 713 manatees killed by cold stress between 1999 and 2011 and the distribution of known refuges, it appears that springs offer manatees the best protection against cold stress. Long-term survival of Florida manatees will require improved efforts to enhance and protect manatee access to and use of warm-water springs as power plant outfalls are shut down.
Orobanche pallidiflora Wimm. & Grab. in Poland: distribution, habitat and host preferences
Renata Piwowarczyk,Piotr Chmielewski,B?a?ej Gierczyk,Bartosz Piwowarski
Acta Societatis Botanicorum Poloniae , 2010, DOI: 10.5586/asbp.2010.025
Abstract: The paper presents ten new localities of Orobanche pallidiflora Wimm. & Grab. from Poland (Middle Roztocze, Równina Be ska plain, Wy yna Malopolska upland, Góry Kaczawskie Mts and Western Bieszczady Mts). Information on hosts, abundance and habitat preferences at the new localities is given and a supplemented map of the distribution in Poland is included.
Distribution and habitat preferences of the genus Biomphalaria (Gastropoda: Planorbidae) in Cuba
Vázquez Perera, Antonio Alejandro;Sánchez Noda, Jorge;Hevia Jiménez, Yosvania;
Memórias do Instituto Oswaldo Cruz , 2010, DOI: 10.1590/S0074-02762010000100005
Abstract: a study was carried out to determine the distribution and habitat preferences of several species of the genus biomphalaria. samples were taken at 350 freshwater locations in cuba. three species of biomphalaria (biomphalaria havanensis, biomphalaria helophila and biomphalaria pallida) were recorded based on their distribution. of the three species, b. havanensis has the weakest distribution because it was identified in only one locality. the other species, b. helophila and b. pallida, are abundant in rivers and dams and have large populations in cuba. however, the only species that appears to occur in ecosystems shared with thiarids is b. pallida, possibly due to recent introduction of thiarids, but always in fewer numbers. here we discuss the possibility of these species to act as intermediary hosts of schistosoma mansoni in cuba over the basis of occurrence in natural and anthropic habitats.
An Initial Classification of Neotropical Water Mites (Acari: Hydrachnidia) Based on Habitat Preferences  [PDF]
Hugo R. Fernández,Odile Fossati-Gaschignard
International Journal of Ecology , 2011, DOI: 10.1155/2011/910540
Abstract: Existing classifications of benthic and interstitial freshwater invertebrates are described and discussed. A classification is proposed for southern neotropical (south of latitude S 15) water mites in relation to their life style and habitat preferences. The classification includes planktonic, superficial, benthic, thermal, and subterranean forms. The diversity of the Hydrachnidia family and genera (22 families, 97 genera, and 521 species) is then analyzed using the new classification. Ubiquitous stygobites deserve special consideration because they move through ecotone zones and tolerate extreme conditions. Water mite communities from a north-western Argentinean stream were first described using a surber net and consequently considered as benthic. Nineteen Hydrachnidia species (from benthic to stygobite) were collected and classified. The vertical distribution observed during the year confirmed the permanent presence of benthic Hydrachnidia, even during the first flood, which is of special importance in running waters. The functional classification we propose will facilitate comparison of fauna from different areas that have different faunistic composition but may have similar functional distribution.
Habitat preferences of small terrestrial mammals in the mountain forest clearings  [cached]
Josef Suchomel,Jarmila Krojerová-Proke?ová,Marta Heroldová,Lubo? Purchart
?asopis Beskydy , 2009,
Abstract: In last ten years strong intention to replace forest monocultures of coniferous species to mixed coniferous -- broadleaved stands which are close to nature composition is promoted. Mountains forests under study are of different character. In Beskydy Mts forests of beech-spruce mixture prevail but in Jeseniky spruce monocultures prevail. In both, reforestation activities are complicated by impact of rodents and influence of industrial immission. Small mammal species were monitored during two successive years on clearings with artificial plantations. In both total abundance of species was similar but with different dominance of the species. Under influence of beech mast year Apodemus flavicollis was dominant in Beskydy Mts but Myodes glareolus in Jeseniky Mts. Higher dominance of Soricidae was in Jeseníky Mts (19%) against Beskydy (6%). The diversity and equitability was similar in both (Jeseniky Mts -- 1.63, Beskydy Mts -- 1.49; 0.84 resp. 0.72). Notable was the high dominance of Microtus agrestis (23 resp. 27%) in both. Abundance of the dominant species was synchronized. Canonic correspondence analyses (CCA) of clearing characteristics show the significant preferences of M. agrestis for higher elevation, more grassy and grassy wastage (higher humidity) environment. This was above all problem of emission clearings. As to M. glareolus, forest weeds preferably of Rubus sp. were responsible for its dominance. These results can contribute to understand rodent habitat preferences and help in prevention against their impact by the way of herb layer management.
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