DOC's work with subantarctic teal

Pete McClelland with the releasing two
of Campbell Island teal, Campbell Island

Recent conservation efforts

The third release of the Campbell Island teal back onto Campbell Island in August 2006 marked the end of a 20 year conservation project for the Department of Conservation.

It had been a long exile for the rare flightless bird after being driven from its Campbell Island home by rats more than 200 years ago.

In fact, up until 1972, when a small group were discovered on rat-free Dent Island, off Campbell Island's coast, the teal was thought to have been extinct for about 100 years. It was from this small group that the Department of Conservation has been able to turn the tide and has been able to establish a thriving teal population back onto Campbell Island.

The third and final release which saw 54 teal being transferred onto Campbell Island followed two earlier releases in 2004 and 2004 where 50 and 55 respectively were transferred back to their island home.

Monitoring

Monitoring of these earlier two releases showed the teal were breeding, a very encouraging result for the programme.

The teal recovery programme started back in 1987 when four birds were transferred from their refuge on 26 ha rat-free Dent Island to the Department of Conservation's National Wildlife Centre at Pukaha Mount Bruce.

However, these evacuees were reluctant to breed and by 1993 not a single egg had been laid. Thankfully a breakthrough came in 1994 when Daisy and Donald paired up and the first two ducklings hatched.

Successfully rearing the first ducklings earned the wildlife centre international recognition and by March 2000 the captive population has risen to 60.

Predator control

Codfish Island / Whenua Hou was chosen to host the insurance population, with two lots of 12 captive-raised birds being released. A successful 88 per cent survival rate resulted. What this demonstrated was that transfer from captivity to a predator free island wild environment can be achieved with little loss.

Following from this it was decided that releases on Campbell Island should be directed from captivity, not via an intermediate "toughing up" stage. However, none of this would have been possible had it not been for the department carrying out the world's largest rat eradication programme on Campbell Island in 2001.

The programme was ambitious as it sought to eradicate Norway rats from Campbell, one of the New Zealand's five subantarctic islands located about 700 km south of the South Island.

The Norway rat is one of the smallest predators killing New Zealand's native species and has proved to be one of the most difficult to eradicate.

Therefore, when the recovery plan for the teal was written by the department in 1993 with the goal being to return the species back to Campbell Island, rats were still present on the island. The technology and expertise available means they couldn't be removed. So the department started planning.

After five years of extensive preparation and research, DOC had developed and refined the techniques that made the rat eradication project feasible.

In 2003 Campbell Island was declared rat free. A year later the first teal were returned home. It was a homecoming that was celebrated both nationally and internationally.

What makes this recovery so special is that a lot of conservation projects don't have an end point, they are an ongoing battle but the teal recovery programme has achieved what the department set out to achieve - the recovery of Campbell Island teal and a big step in the restoration of Campbell Island.

Recovery plan in action:

The Department of Conservation's Subantarctic Teal Recovery Plan was written in 1993. This plan set in place a series of steps to promote the recovery of the teal. The plan also outlines different management options.

The long-term vision of the plan is:

"To improve the conservation status of both Campbell Island teal and the Auckland Island teal from endangered to rare by re-establishing them in their former ranges so that further intensive management is no longer required." A vision which in 2006 was realised for the Campbell Island teal following three successful transfers in 2004, 2005 and 2006. The 159 teal released during those years are now, without management assistance, recolonising their former home.

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