Natural Heritage

28 posts

Articles by various authors on the unique natural and cultural heritage of the Chatham Islands and the ongoing efforts to conserve it.  If you’d like to contribute an article contact dave@kiwifavourites.co.nz

Chatham Island toetoe

Study reveals low levels of genetic diversity in Chatham Islands toetoe

A study just published in Pacific Conservation Biology reveals that the Chatham Island toetoe (Austroderiaturbaria) populations have very little significant genetic variation (Houliston et al. 2012). The discovery comes as somewhat of a worrying surprise to plant conservationists. Previously, without the ability to check levels of genetic variation the Department […]

Parea - Chatham Island pigeon

Parea – the Chatham Island pigeon

Status (2008):Population (2009):Trend: Critically Endangered600 individualsImproving Larger and heavier than its mainland cousin, the parea or Chatham Island pigeon is today largely confined to the south-western corner of Chatham Island.  Like several other Chatham species the parea had a close brush with extinction, with the population dropping to 40-45 birds […]

Chatham petrel (Pterodroma axillaris)

Chatham petrel population growing

Status (2012):Population (2010):Trend: Nationally vulnerable1,400 individualsImproving Probably once abundant throughout the Chatham Islands, human exploitation, habitat destruction and introduced predators saw the Chatham petrel restricted to Rangatira or Southeast Island by the time of its discovery in 1892. Until 1961 farming activity on Rangatira resulted in the petrels being confined […]

Chatham Island oystercatchers

Many of us are familiar with New Zealand’s variable oystercatcher, the black and white (or sometimes entirely black) wader with bright orange legs and bill that we encounter on beaches around the country. What most don’t know is that the Chatham Islands have their own version, the Chatham Island oystercatcher and that it narrowly escaped extinction in recent times.

[i]Menegazzia pulchra[/i] Photo: Peter de Lange

An uncommon lichen Menegazzia pulchra found on the Chatham Islands

While our knowledge of New Zealand lichens is rapidly growing we are still unclear of what is present over large parts of the New Zealand Botanical Region. One key area of lichen ignorance is the Chatham Islands. The current lichen flora (Galloway 2007) records just 48 species for the islands. Yet despite that, the Chathams are the type locality for three species, and one of these, Caloplaca maculata, is endemic to the islands (see Galloway 2007; Johnson 2008; de Lange 2009).

In 1996 two of us, Peter de Lange & Gillian Crowcroft, visited the islands for their first time during which they collected a few lichens from the southern part of Rekohu (Chatham Island). Since then, but most especially in 2007 and 2008, Peter de Lange (mostly aided by Peter Heenan), has made a special effort to collect lichens to improve our knowledge of their diversity on the island. As a result of these gatherings, Peter de Lange and David Galloway (the author of the New Zealand Lichen flora series (Galloway 1985, 2007)) are working with the other key Chatham Islands lichen collectors Peter Johnson and Allison Knight, and lichenologist Dan Blanchon to prepare a checklist of the lichen flora for that island group (Galloway et al. in prep.). As part of that project they have been systematically working through all known collections from the island group held in New Zealand herbaria. In the process some rather interesting and at times unexpected finds are being made.