<I>Mystacina tuberculata</I>

Roads and wildlife: the need for evidence-based decisions; New Zealand bats as a case study

Roads and associated land transport activities can affect a wide range of indigenous terrestrial vertebrate species. National legislation, particularly the Resource Management Act 1991, requires that developers ‘avoid, remedy or mitigate’ the adverse environmental effects of their activities. How these effects are identified and managed in New Zealand varies because regulators and land transport contractors deal with these issues on a case-by-case basis.

Non-native pollen found in short-tailed bat (Mystacina tuberculata) guano from the central North Island

We analysed pollen in short-tailed bat guano samples from Rangataua Forest and from guano and pollen found in bat holding bags used in the Kaimanawa Range, central North Island. Fifty seven percent of the pollen from Rangataua was from a previously unrecorded source and was tentatively identified as Trachycarpus fortunei (Chinese windmill palm). The significant remaining pollen was identified as Collospermum (15%) and Nothofagus (14%) from Rangataua, and Collospermum (90%) and Nothofagus (6%) from Kaimanawa.

A Survey of the Distribution, Seasonal Activity and Roost Sites of New Zealand Bats

The lesser short-tailed bat (Mystacina t. tuberculata) has been found in 18 locations in indigenous forest in North Island since 1961, mainly in Northland kauri forest (including Little Barrier Island), on the volcanic plateau (including Tongariro National Park), Urewera National Park and in Tararua Range. In South Island this bat has only been reported once since 1961, in North West Nelson Forest Park, and must be regarded as endangered. It is present also on Codfish Island, but is thought to have become extinct on Big South Cape and Solomon Islands about 1967.

Vertical variation in flight activity of the lesser short-tailed bat in podocarp and beech forests, Central North Island, New Zealand

Designing robust monitoring programmes for cryptic species is particularly difficult. Not detecting a species does not necessarily mean that it is absent from the sampling area. A conclusion of absence made in error can lead to misguided inferences about distribution, colonisation and local extinction estimates, which in turn affects where and how conservation actions are undertaken. It is therefore important to investigate monitoring techniques that reduce the non-detection rate of cryptic species.