STRENGTHENING THE WILD POPULATIONS OF A CRITICALLY ENDANGERED SPECIES

The Helmeted Honeyeater Recovery Team is intensively researching ways of sustaining the last two wild populations of the Critically Endangered Helmeted Honeyeater (Lichenostomus melanops cassidix).

AIM

This project aims to increase the number of Helmeted Honeyeaters living in the wild at Bunyip State Park and Yellingbo Nature Conservation Reserve.

METHODS

Two ways of increasing the populations are being trialled:

Nest supplementation
Wild Helmeted Honeyeater breeding is intensively monitored so that wild nests can be supplemented with eggs or nestlings from captivity.

Release of captive-bred immature birds
Groups of captive-bred immature Helmeted Honeyeaters are released at the end of each breeding season to bolster wild populations. While in captivity, the groups are socialised to maximise group cohesion. The birds then have short period of on-site acclimatisation prior to release.

Direct observations and remote video surveillance are used to closely monitor the survivorship, site fidelity and breeding contribution of birds, and so compare the relative success of the two methods.

Researchers are also analysing the genetic structure (genetic variation and relatedness) of the wild Helmeted Honeyeater populations.  Populations can then be managed to maximise the genetic diversity of wild and captive populations, and reduce the risk of in-breeding. Translocations between populations will be conducted where possible.

RESULTS

Nest supplementation: Eight eggs/chicks from captivity were placed into wild bird nests during the 2008-09 and 2009-10 breeding seasons; six of these successfully fledged and two were resighted in February 2010.  One unsuccessful chick was eaten by a tiger snake.

Release: Thirteen immature captive-bred Helmeted Honeyeaters were released at Bunyip State Park, and 12 at Yellingbo Nature Conservation Reserve in autumn 2009. By January 2010, three 'releasees' at Bunyip and seven 'releasees' at Yellingbo could still be accounted for.  One bird released at Yellingbo successfully bred during the 2009-10 breeding season.  Four other 'releasees' attempted to breed but were unsuccessful.

Genetics: Blood samples were collected from 17 breeding adult Helmeted Honeyeaters in 2009 for genetic analysis. Blood sampling of wild birds will continue in 2010.  During the 2008-09 and 2009-10 breeding seasons, five eggs/chicks were swapped between the Yellingbo and Bunyip populations. All of these fledged successfully.  At Bunyip, only two nests fledged young because of predation and nest abandonment (the eggs were successfully rescued in the latter case).

PROJECT OUTCOMES

So far, this project has shown that nest supplementation and release of immature birds can be used to supplement wild populations of Helmeted Honeyeaters. It is also possible to swap eggs/nestlings between wild populations for genetic management. Unfortunately, the success of these management actions is threatened by the predation of nests and fledglings (and perhaps other mortality factors).

This project will continue for another two years to increase sample sizes, gain longer-term post-action data on the birds' success, and establish the genetic structure of the wild populations.

FOR MORE INFORMATION

- on the breeding program for Helmeted Honeyeaters at Healesville Sanctuary - click here.

- on the National Recovery Plan for Helmeted Honeyeaters - click here.

- on Friends of the Helmeted Honeyeater - click here.