Why are some weta (Orthoptera: Stenopelmatidae) vulnerable yet others are common?

  title={Why are some weta (Orthoptera: Stenopelmatidae) vulnerable yet others are common?},
  author={George W. Gibbs},
  journal={Journal of Insect Conservation},
  • G. Gibbs
  • Published 12 September 1998
  • Environmental Science
  • Journal of Insect Conservation
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… 

Where have all the weta gone? Results after two decades of transferring a threatened New Zealand giant weta, Deinacrida mahoenui

Weta were found at very low densities at Mangaokewa Scenic Reserve and Tikikaru and it is likely their populations are not viable in the long term and further efforts to establish Mahoenui giant weta populations should be in mammal-free sanctuaries containing native forest.

Hydrolutos breweri sp. n., a new aquatic Lutosini species (Orthoptera: Anostostomatidae) from Churí-tepui (Chimantá Massif, Venezuela)

Hydrolutos breweri, a new species of Lutosini from Cueva Charles Brewer, Venezuela, is described and figured, representing an unusual orthopteran with sternal and pleural area covered by fine microtrichia forming a plastron.

Life cycle , survival rates and longevity of an alpine weta Hemideina maori ( Orthoptera : Anostostomatidae ) determined using mark-recapture analysis

Although reproductive and behavioural studies have been conducted on captive tree weta, there have been very few ecological field studies of any of the weta species involving free-ranging, marked

Response of a Tree Weta Population (Hemideina crassidens) After Eradication of the Polynesian Rat from a New Zealand Island

It was concluded that endemic tree weta are well adapted to withstand some introduced vertebrate predators but are able to live a more “relaxed” lifestyle in the absence of this predation.

Do New Zealand invertebrates reflect the dominance of birds in their evolutionary history

It would be necessary to compare the New Zealand invertebrate fauna with that of mammal-dominated lands in greater detail than is available today before it could be asserted whether any unique anti-predator characteristics have evolved.

Silent assassins: predation of native New Zealand trichopteran eggs by non-native freshwater gastropods

The trichopteran egg masses tested did not succumb to predation by the native Potamopyrgus but are highly vulnerable topredation by a larger non-native snail.

Dramatic increases in weta (Orthoptera) following mammal eradication on Maungatautari - evidence from pitfalls and tracking tunnels.

There were dramatic increases in weta pitfall captures, weta tracking rates and the incidence of weta footprinting per tracking card, and counting squares tracked per card gave a more sensitive and precise indicator of response to mammal eradication than simply recording presence and absence of tracks.

Evolution of New Zealand insects: summary and prospectus for future research

The origins and evolution of four prominent communities within the insect fauna: terrestrial lowland insects, alpine insects, aquatic insects and insect communities from offshore islands are discussed.

After the deluge: mitochondrial DNA indicates Miocene radiation and Pliocene adaptation of tree and giant weta (Orthoptera: Anostostomatidae)

It is hypothesize that at least three distinct groups of weta survived the Oligocene marine transgression and radiated subsequently, and patterns of genetic diversity within species reflect, in some instances, geographical subdivision in the Pliocene, and in other cases, Pleistocene range changes resulting from climate change.

Investigating host plant association, calling activity, and sexual dimorphism in Indian Gryllacropsis sp. (Orthoptera: Anostostomatidae)

These polyphagous insects provide insights on understanding ecological specialization due to host plant association, signal evolution, and mating behavior and can be used for identification of sexes in the field.



Tree wetas (Hemideina crassicruris) (Orthoptera: Stenopelmatidae) of Stephens Island, Cook Strait

Tree wetas (Hemideina crassicruris) were studied in kohekohe (Dysoxylum spectabile) forest on Stephens Island, Cook Strait between 5 and 17 January 1978, and reached larger sizes overall and males have relatively larger heads, than in other populations of the Cook Strait.

Past distribution of large weevils (Coleoptera: Curculionidae) in the South Island, New Zealand, based on Holocene fossil remains

A survey of 12 fossil sites in North and South Canterbury, where faunal remains were accumulated by the apparently extinct laughing owl and the New Zealand falcon, revealed sediments containing abundant remains of not only bones but also invertebrates, including several species of large weevils (Curculionidae), including Anagotus stephenensis Kuschel, A. rugosus, and Ectopsis ferrugalis Broun.

The handbook of New Zealand mammals

This book is the first comprehensive account of all 46 species of land-breeding mammals known in New Zealand, native and exotic, wild and feral, living and extinct, and brings together much information which has been gathered from widely scattered sources or was hitherto unpublished.

A comparative study of the Wellington tree weta, Hemideina crassidens (Blanchard, 1851) in the presence and absence of rodents

  • Unpublished MSc thesis in Library,
  • 1995

The conservation of a giant weta (Deinacrida n. sp. Orthoptera: Stenopelmatidae) at Mahoenui, King Country: habitat use, and other aspects of its ecology.

Giant weta occurred mostly on steep (>21 O) slopes with north- to east-facing aspects, areas regularly used by cattle and goats, open areas, and middle-aged gorse bushes or old and senescent trees (> 15 years old).

Arrival of rats in New Zealand

Arrival of rats

  • New Zealand. Nature
  • 1996

Notes on the genus Deinacrida in New Zealand

  • Trans . Proc . NZ Inst .
  • 1871