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Other Beetles (other + beetle)
Selected AbstractsDensity-mediated responses of bark beetles to host allelochemicals: a link between individual behaviour and population dynamicsECOLOGICAL ENTOMOLOGY, Issue 4 2002Kimberly F. Wallin Abstract ,1. Bark beetles (Coleoptera: Scolytidae) accept or reject host conifers based partly on concentrations of phloem monoterpenes. They colonise trees in aggregations, in response to pheromones that attract flying beetles to trees undergoing colonisation. A series of entry and gallery construction assays was conducted to determine whether responses by individual beetles to monoterpenes are altered by pheromones and/or the presence of other beetles. 2. Entry into the amended media by Ips pini and the length of time until entry were not influenced by the presence of aggregation pheromones. 3. Entry into amended media was influenced by the presence of other beetles on the surface of, or constructing galleries in, the substrate. The effects of alpha-pinene and limonene on host entry behaviour were mediated by the density of beetles on the surface of the assay arena, and by the density of beetles constructing galleries within the medium. 4. The percentage of beetles entering medium amended with higher concentrations of monoterpenes increased with increased density of beetles on the surface of the assay arena, until a threshold density of three or four beetles per assay arena, after which entrance rate declined. 5. The presence of other beetles constructing galleries elicited more rapid entry by the test beetles. 6. Gallery lengths were generally higher in the presence of aggregation pheromones. 7. Gallery lengths increased with increased density of beetles within the assay arena. 8. These results suggest a link between the density of bark beetles and responses of individuals. This linkage may partially explain behavioural changes observed during population eruptions. [source] Brood size reduction in Nicrophorus vespilloides after usurpation of carrion from Nicrophorus quadripunctatus (Coleoptera: Silphidae)ENTOMOLOGICAL SCIENCE, Issue 3 2004Seizi SUZUKI Abstract Burying beetles bury small vertebrate carcasses, which become food for their larvae. They sometimes usurp carcasses occupied and buried by other beetles. Brood sizes of intraspecific and interspecific intruders were examined using Nicrophorus quadripunctatus as the resident. The brood sizes of usurpers were not reduced relative to control brood sizes when the usurper was conspecific, but were reduced when the usurper was heterospecific (N. vespilloides). [source] DNA-based identification of preys from non-destructive, total DNA extractions of predators using arthropod universal primersMOLECULAR ECOLOGY RESOURCES, Issue 3 2006JOAN PONS Abstract Here, I show that prey sequences can be detected from DNA of tiger beetles of the genus Rivacindela using whole specimens, nondestructive methods, and universal cytochrome b primers for arthropods. BLAST searches of the obtained sequences against public databases revealed that the diet of Rivacindela is mostly composed of flies but also termites and other beetles. Accurate determination of order, family and even genus was achieved in most cases but rarely to species level. Results suggest that stored DNA samples extracted from whole predatory specimens could be an alternative to dissected gut contents as starting source for DNA-based dietary studies. [source] Effects of seasonal variation in salinity on a population of Enochrus bicolor Fabricius 1792 (Coleoptera: Hydrophilidae) and implications for other beetles of conservation interestAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 1 2003M.T. Greenwood Abstract 1.A population of Enochrus bicolor (Fabricius) was monitored over a 4-year period (March 1997,March 2001) from a coastal brackish pool in S.E. Essex. This water beetle, together with Ochthebius marinus (Payk.), O. viridis Peyrhiff, O. punctatus Steph., Hygrotus parallelogrammus (Ahrens), Berosus affinis Brulle, Agabus conspersus, (Marsham), Rhantus frontalis (Marsham), R. suturalis (MacLeay), Paracymus aeneus (Germar), and Haliplus apicalis Thompson, are all taxa of conservation interest. 2.Enochrus bicolor was present in most months, with greatest adult abundances being recorded in August and September each year. 3.During the study period salinity values ranged from 4.7 ppt (parts per thousand) to 62.6 ppt. 4.Correlation analysis and the development of regression models indicated that the highest abundances of E. bicolor coincided with maximum water temperature in the late summer,early autumn. However, when the natural seasonal signal was removed by standardizing the series, a relatively weak association with the relative abundance of E. bicolor and conductivity was observed. 5.The conservation of E. bicolor and other organisms associated with brackish water habitats subject to irregular marine inundation is considered. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||