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Surrounding Habitat (surrounding + habitat)
Selected AbstractsMovement trajectories and habitat partitioning of small mammals in logged and unlogged rain forests on BorneoJOURNAL OF ANIMAL ECOLOGY, Issue 5 2006KONSTANS WELLS Summary 1Non-volant animals in tropical rain forests differ in their ability to exploit the habitat above the forest floor and also in their response to habitat variability. It is predicted that specific movement trajectories are determined both by intrinsic factors such as ecological specialization, morphology and body size and by structural features of the surrounding habitat such as undergrowth and availability of supportive structures. 2We applied spool-and-line tracking in order to describe movement trajectories and habitat segregation of eight species of small mammals from an assemblage of Muridae, Tupaiidae and Sciuridae in the rain forest of Borneo where we followed a total of 13 525 m path. We also analysed specific changes in the movement patterns of the small mammals in relation to habitat stratification between logged and unlogged forests. Variables related to climbing activity of the tracked species as well as the supportive structures of the vegetation and undergrowth density were measured along their tracks. 3Movement patterns of the small mammals differed significantly between species. Most similarities were found in congeneric species that converged strongly in body size and morphology. All species were affected in their movement patterns by the altered forest structure in logged forests with most differences found in Leopoldamys sabanus. However, the large proportions of short step lengths found in all species for both forest types and similar path tortuosity suggest that the main movement strategies of the small mammals were not influenced by logging but comprised generally a response to the heterogeneous habitat as opposed to random movement strategies predicted for homogeneous environments. 4Overall shifts in microhabitat use showed no coherent trend among species. Multivariate (principal component) analysis revealed contrasting trends for convergent species, in particular for Maxomys rajah and M. surifer as well as for Tupaia longipes and T. tana, suggesting that each species was uniquely affected in its movement trajectories by a multiple set of environmental and intrinsic features. [source] Love of Nurse Plants is Not Enough for Restoring Oak Forests in a Seasonally Dry Tropical EnvironmentRESTORATION ECOLOGY, Issue 5 2009Ernesto I. Badano Abstract The highest concentration of oak species in the world occurs in Mexico, but human activities have strongly degraded these oak forests. Mexican oaks have high economic, social, and cultural value, and restoring these forests is of paramount importance for the people of Mexico. Here, we propose a method for restoring oak forests using native shrubs that colonize degraded areas as nurse plants for oak seedlings. To test the viability of this proposal, seedling transplant experiments were performed in a degraded area near a protected oak forest relict. Two pioneer shrubs were identified as potential nurse species: Mimosa luisana and Senecio sp. The target oak species was Quercus castanea. Oak seedlings were located beneath the canopies of both shrubs and in the surrounding area without shrub cover. Water is a limiting resource for oak establishment in seasonally dry environments; therefore, we included irrigation systems in our experimental design to determine whether the combination of nurse plants plus watering led to higher rate of survival than the presence of nurse species alone. Seedling survival without watering was less than 20% both beneath nurse species and in the surrounding habitat. When water was supplied, survival rate beneath nurse species increased up to 58% while survival in the surrounding habitat did not differ from that observed in treatments without watering. Our results indicate that survival rate of oak seedlings is increased by the presence of nurse plants only when water is supplied. This suggests that restoration of oak forests in these degraded areas requires both nurse plants and watering. [source] Pest reduction services by birds in shade and sun coffee in JamaicaANIMAL CONSERVATION, Issue 2 2010M. D. Johnson Abstract The reduction of insect pests by birds in agriculture may provide an incentive for farming practices that enhance the conservation value of farms for birds and other wildlife. We investigated pest reduction services by insectivorous birds on a coffee farm in Jamaica, West Indies. Our results suggest that birds reduced insect pests on our study site. Infestation by the coffee berry borer Hypothenemus hampei, the world's most damaging insect pest in coffee, was significantly elevated on coffee shrubs from which birds were experimentally excluded from foraging. Overall, we estimated the economic value of the reduction of coffee berry borer by birds on the 18 ha farm to be US$310 ha,1 for the 2006 harvest season. These results provide additional evidence that birds can reduce numbers of economically damaging pests and enhance crop yields in coffee farms. Differences in the magnitude of pest reduction within the farm may have resulted from variation in shade management and surrounding habitats, and these factors merit further investigation. [source] Directionality of pre- and post-breeding migrations of a marbled newt population (Triturus marmoratus): implications for buffer zone managementAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2005P. Marty Abstract 1.The marbled newt, Triturus marmoratus, is a vulnerable urodele species (listed on Annex IV of the European Habitats Directive). However, biological information about their migration and the terrestrial habitats they use is relatively scarce. In order to investigate the influence of the surrounding habitats of a local pond on the directions of pre- and post-breeding migrations, adult newts were monitored over two successive years (from February 2000 to June 2001) at a permanent pond in south-western France using a drift fence and pitfall traps. 2.In both sexes the entry and exit directions were non-randomly distributed. Furthermore, males and females generally followed similar directions facing an oak forest and avoiding barren areas. However, the directions followed by postbreeding migrants leaving the pond differed from those they followed when coming to the pond. 3.The distribution of captures around the pond was related to environmental factors, and more precisely to vegetation within the immediate surroundings of the pond. 4.The environmental conditions occurring at the end of the spring postbreeding migration differed greatly from those occurring during the winter prebreeding migration. Thus, vegetation does not exert similar attraction during the two migration periods. 5.This raises the importance of microhabitat diversity in the vicinity of the breeding pond, which provides a wide range of suitable shelters in different migration periods. Conservation planning must take into account the ecological requirements of this endangered species in managing buffer zones around the breeding sites. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||