Why are some weta (Orthoptera: Stenopelmatidae) vulnerable yet others are common?
- George W. Gibbs
- … show all 1 hide
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
The large (4 g) to very large (40 g) stenopelmatid orthopterans of New Zealand are known collectively as weta. A consideration of 20 species of Hemideina, Deinacrida and tusked weta reveals that at one end of a vulnerability gradient are those species which thrive in the presence of key predators (rats), while at the other end are species that have become extinct on the mainland but still survive on predator-free island refuges. Habitat modification does not appear to be a factor in these extinctions. This paper reviews the lifestyles and some important biotic parameters that seem to determine their relative vulnerability along this gradient. When predators are present, the factors leading to extinction are large body size, use of temporary refuges, protective quality of the refuges, time spent on the ground and the effectiveness of their defensive behaviour.
- Buller, W. (1871) Notes on the genus Deinacrida in New Zealand. Trans. Proc. NZ Inst. 3, 34–37.
- Gibbs, G.W. and McIntyre, M.E. (1997) Abundance and future options for wetapunga on Little Barrier Island. Sci. Conserv. 48, 5–24.
- Holdaway, R.N. (1996) Arrival of rats in New Zealand. Nature 384, 225–6.
- King, C.M. (ed.) (1990) The Handbook of New Zealand Mammals. Auckland: Oxford University Press.
- Kuschel, G. and Worthy, T.H. (1996) Past distribution of large weevils (Coleoptera: Curculionidae) in the South Island, New Zealand, based on Holocene fossil remains. NZ Entomol. 19, 15–22.
- Moller, H. (1985) Tree wetas (Hemideina crassicruris) (Orthoptera: Stenopelmatidae) of Stephens Island, Cook Strait. NZ J. Zool. 12, 55–69.
- Rufaut, C.G. (1995) A comparative study of the Wellington tree weta, Hemideina crassidens (Blanchard, 1851) in the presence and absence of rodents. Unpublished MSc thesis in Library, Victoria University, Wellington, New Zealand.
- Sherley, G.H. and Hayes, L.M. (1993) The conservation of giant weta (Deinacrida n.sp. Orthoptera: Stenopelmatidae) at Mahoenui, King Country: habitat use, and other aspects of its ecology. NZ Entomol. 16, 55–68.
- Why are some weta (Orthoptera: Stenopelmatidae) vulnerable yet others are common?
Journal of Insect Conservation
Volume 2, Issue 3-4 , pp 161-166
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers
- Additional Links
- mammalian predators
- body size
- daytime refuges
- threat posture.
- Industry Sectors
- George W. Gibbs (1)
- Author Affiliations
- 1. School of Biological Sciences, Victoria University, PO Box 600, Wellington, New Zealand