Patterns of nesting and dung burial in Onitis dung beetles: implications for pasture productivity and fly control.

Published online
15 Mar 1988
Content type
Journal article
Journal title
Journal of Applied Ecology
DOI
10.2307/2403984

Author(s)
Edwards, P. B. & Aschenborn, H. H.

Publication language
English
Location
Namibia & Africa South of Sahara & Africa & Australia & New South Wales & South Africa

Abstract

The nesting biology of Onitis viridulus, O. fulgidus, O. obscurus, O. alexis, O. perpunctatus, O. caffer, O. aygulus [a synonym of O. alexis], O. tortuosus, O. deceptor, O. uncinatus, O. picticollis and O. pecuarius was studied in South Africa and Australia in the context of pasture productivity and control of dung-breeding flies. The rate and pattern of burial of 1000-g pads were observed at 25°C for O. viridulus, O. caffer, O. aygulus, O. uncinatus and O. pecuarius. O. viridulus and O. pecuarius did not initiate rapid dung burial for up to 9 days after being added to cattle dung. O. caffer and O. aygulus commenced burial within 2-5 days, and maintained a steady burial rate of 57-92 g per pair. One pair of O. caffer buried 780 g in 12 days. O. uncinatus buried dung in a stepwise pattern, burying about 120 g of dung overnight, with an average of 4 days between burial episodes. It was considered the best species for fly control, since substantial amounts of dung were buried on the 1st night after pad colonization. O. viridulus was considered to be least suitable, since burial did not commence until 6-9 days had elapsed, by which time, at 25°C, larvae of Musca vetustissima or Haematobia irritans exigua would have completed feeding and left the dung pad. No larvae survived in the brood dung of O. alexis, O. pecuarius or O. caffer. This was mainly attributed to removal of moisture from brood dung by the beetles, although the apparent low water content of brood dung was partly due to the incorporation of soil into the broods. Species were divided into 5 groups, based on their nest structure and method of dung burial. The mean depth at which nests were buried in moist sandy soil ranged from 10 to 103 cm for individual species.

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