Campbell Island teal  (Anas nesiotis)

Having disappeared from much of its former range, the Campbell Island teal population has reached critically low numbers and now clings to a precarious existence. This bird’s extirpation from it presumed former stronghold, Campbell Island, has largely been attributed to predation by introduced Norway rats (Rattus norvegicus) that got ashore from sealing and whaling ships in the early 19th Century (4). Present-day potential threats include the accidental introduction of predators or avian disease to Dent Island, the bird’s last natural refuge, or even severe weather conditions, which could have a catastrophic effect (6). Indeed, with such a small current population and limited natural range, this bird is now extremely vulnerable; just a single event is capable of driving it to complete extinction (5).

The outlook for the Campbell Island teal looked bleak when first rediscovered in 1975, but thankfully since then there has been fantastic progress with captive breeding programmes and the population has increased to a healthier, though still unstable, level (5). Captive breeding was started by New Zealand’s Department of Conservation in 1984, from three males and one female taken from the small population on Dent Island, and another four males and three females captured in 1990. The first duckling finally hatched in 1994 at the Pukaha Mt Bruce National Wildlife Centre, receiving international attention, and by 2000 the captive population had reached 60 (4). The Department of Conservation initially released a total of 24 captive-bred birds on to the predator-free Codfish Island in 1999 and 2000 as an insurance population, and to be eventually used to restock Campbell Island (4) (5). These had an 88 percent survival rate. With this success, the Department of Conservation decided to translocate captive-bred birds directly to Campbell Island, made viable by a successful rat and cat eradication programme in 2001 (4). Thus, 50 teal, including 28 from Pukaha Mount Bruce and 22 from Codfish Island were released onto Campbell Island in September 2004, and a further 55 in September 2005 and 54 in 2006 (4) (5). A check in February 2005 found no evidence that the first batch of released birds had bred, but this may be due to their being moved close to the breeding season (4). Two decades of conservation effort have brought this bird back from extinction on Campbell Island, and meant that it now has a good chance of being able to recover and thrive once more in its native home (7).