1. ¹Allan Wilson Centre for Molecular Ecology and Evolution, Institute of Molecular BioSciences, Massey University, Auckland, New Zealand
2. ²Canterbury Museum, Christchurch, New Zealand
3. ³Taiko Trust, Whangarei, New Zealand
4. ⁴Allan Wilson Centre for Molecular Ecology and Evolution, School of Biological Sciences, University of Auckland, Auckland, New Zealand

Correspondence: Professor DM Lambert, Griffith School of Environment and School of Biomolecular and Physical Sciences, Griffith University, 170 Kessels Road, Nathan, Qld. 4111, Australia. E-mail: d.lambert@griffith.edu.au

Received 22 December 2007; Revised 8 June 2008; Accepted 10 June 2008; Published online 3 September 2008.

Abstract

The Chatham Island Taiko (Tchaik, Pterodroma magentae) is one of the world's rarest seabirds. In the past there were millions of breeding pairs of Taiko and it was the most abundant burrowing petrel on Chatham Island. The present population consists of just 120–150 birds, including only 8–15 breeding pairs. Surprisingly high genetic variation was revealed by DNA sequencing of almost every known adult Taiko (N=90). Given the massive population decline, genetic variation may have been even larger in the past. Therefore, we investigated past genetic diversity by sequencing regions of the mitochondrial cytochrome b gene in 44 ancient Taiko bones. We identified a total of 12 haplotypes in Taiko. Eight haplotypes were revealed in the ancient DNA: four were unique to the bones and four corresponded to those found in the modern Taiko population. Surprisingly, despite the critically endangered status of the Taiko, no significant reduction in mitochondrial DNA haplotype diversity was observed between ancient samples (N=44) and modern adult Taiko (N=90). The modern population may have however lost four haplotypes present in the ancient populations.