Bankside Scientific Reserve---an important refuge for Canterbury's dryland insect fauna
The Canterbury Branch of the Entomological Society undertook a brief re-survey of the insect fauna at the Bankside Scientific Reserve during summer 2009/10, thirty-one years after an initial survey by Lincoln University staff. This tiny reserve (2.6 ha) supports dryland vegetation, which at the time of its creation was mainly indigenous. Now that the reserve is surrounded by irrigated pasture, the aim of this assessment was to see whether the indigenous invertebrate component had survived. Both the Canterbury ground beetles, Megadromus antarcticus and Metaglymma monilifer, remained relatively common, but the uncommon tenebrionid, Mimopeus tibialis, endemic to lowland Canterbury appears to have declined in numbers since the original survey. Two specimens of a large rove beetle, Hadrotes wakefieldi, which is known from only a few collections in mid-Canterbury, were collected in pitfall and pan traps in 2009/10. The weevil, Nicaeana n. sp., a probable Canterbury endemic, was collected from native broom during both surveys. The flightless longhorn beetles, Ptinosoma ptinoides (a litter feeding species), and Xylotoloides wakefieldi, collected from matagouri, still survive at the site, even though they were not collected in the reserve in 1978/79. The rarely collected bent-backed bug, Romna oculata, was common on native broom. The generally montane short-horned grasshopper, Sigaus campestris, was not re-collected. We conclude that a number of species restricted to dryland habitat in Canterbury survive in this reserve. There are very few areas of similar vegetation left on the Canterbury Plains, which have been heavily modified for intensive agriculture. This remnant reserve is therefore significant for conservation of indigenous insects and other invertebrates in spite of its small size.