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Dung Beetle Abundance (dung + beetle_abundance)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

Dung Beetle Assemblages and Seasonality in Primary Forest and Forest Fragments on Agricultural Landscapes in Budongo, Uganda

BIOTROPICA, Issue 4 2009
Philip Nyeko
ABSTRACT Very little is known about the diversity of arthropods in the fast-disappearing fragments of natural forests in sub-Saharan Africa. This study investigated: (1) the influence of forest fragment characteristics on dung beetle species richness, composition, abundance, and diversity; and (2) the relationship between dung beetle assemblages and rainfall pattern. Beetles were sampled through 12 mo using dung baited pitfall traps. A total of 18,073 dung beetles belonging to three subfamilies and 45 species were captured. The subfamily Scarabaeinae was the most abundant (99%) and species rich (89%). Fast-burying tunnellers (paracoprids) were the most dominant functional group. Catharsius sesostris, Copris nepos, and Heliocopris punctiventris were the three most abundant species, and had the highest contributions to dissimilarities between forests. With few exceptions, dung beetle abundance, species richness, and diversity were generally higher in larger forest fragments (100,150 ha) than in smaller ones (10,50 ha) and the nature reserve (1042 ha). Forest fragment size had a highly significant positive relationship with beetle abundance, but only when the nature reserve is excluded in the analysis. Dung beetle abundance and species richness showed direct weak relationships with litter depth (positive) and groundcover (negative) but not tree density, tree species richness, and fragment isolation distance. Dung beetle abundance and species richness were strongly correlated with monthly changes in rainfall. Results of this study indicate that forest fragments on agricultural lands in the Budongo landscape, especially medium-sized (100,150 ha) ones, represent important conservation areas for dung beetles. [source]

Improving the design and management of forest strips in human-dominated tropical landscapes: a field test on Amazonian dung beetles

JOURNAL OF APPLIED ECOLOGY, Issue 4 2010
Jos Barlow
Summary 1.,The future of tropical forest species depends in part on their ability to survive in human-modified landscapes. Forest strips present a priority area for biodiversity research because they are a common feature of many managed landscapes, are often afforded a high level of legal protection, and can provide a cost-effective and politically acceptable conservation strategy. 2.,Despite the potential conservation benefits that could be provided by forest strips, ecologists currently lack sufficient evidence to inform policy and guide their design and management. 3.,We used a quasi-experimental landscape in the Brazilian Amazon to test the importance of four management-relevant variables (forest type, isolation distance, forest structure, and large mammal activity) on the potential biodiversity conservation value of narrow forest strips for dung beetles. 4.,Information-theoretic model selection based on AICc revealed strong support for the influence of large mammal activity and forest type on dung beetle abundance; isolation distance on species richness; and forest structure on the relative abundance of matrix-tolerant species. Multi-dimensional scaling showed a strong influence of forest type and isolation on community composition and structure, with riparian and dry-land strips having complementary sets of species. 5.,Synthesis and applications. To enhance the conservation value and ecological integrity of forest strips in human-modified landscapes we recommend that strip design considers both isolation distance and whether or not the strips encompass perennial streams. In addition, we identify the maintenance of forest structure and the protection of large mammal populations as being crucially important for conserving forest dung beetle communities. [source]

Factors influencing duiker dung decay in north-east Gabon: are dung beetles hiding duikers?

AFRICAN JOURNAL OF ECOLOGY, Issue 1 2009
Nathalie Van Vliet
Abstract We analysed seasonality of dung decay time and the influence of rainfall, leaf fall, beetle attack and moisture on dung decay. Our study was carried out at the Ipassa Reserve, north-east Gabon. We compared the seasonality of dung decay with the seasonality of dung beetle abundance and guild structure. Dung beetle activity was the main factor influencing dung decay in our study site. Decay time was the highest during the main dry season (3.4 days) and the lowest during the short rainy season (0.7 days). Dung decay time was closely related to dung beetle abundance, especially to the abundance of nocturnal beetles. We discuss the implications of such results for duiker survey methods based on dung pellet counts in areas where decay time is extremely short or unknown. Résumé Nous avons analysé le caractère saisonnier de la durée de décomposition des crottes et l'influence des chutes de pluie, des chutes de feuilles, des attaques de coléoptères et de l'humidité sur la décomposition des crottes. Notre étude s'est déroulée dans la Réserve d'Ipassa, au nord-est du Gabon. Nous avons comparé le caractère saisonnier de la décomposition des crottes avec celui de l'abondance des coléoptères et la structure des guildes. L'activité des bousiers était le principal facteur influençant la décomposition des crottes sur notre site d'étude. La durée de la décomposition était plus longue pendant la grande saison sèche (3,4 jours) et plus courte pendant la petite saison des pluies (0,7 jour). La durée de la décomposition était étroitement liée à l'abondance des bousiers, spécialement celle des coléoptères nocturnes. Nous discutons les implications de ces résultats pour les méthodes de recensement des céphalophes qui se basent sur le comptage des crottes, dans des régions où le temps de décomposition est extrêmement court, ou inconnu. [source]