Guest blog by Dr Steffen Oppel, Senior Conservation Scientist, RSPB Centre for Conservation Science

Henderson Island (Pitcairn Group, UK Overseas Territory) is one of the most remote islands on the planet. It is uninhabited, and situated over 3,000 miles from the nearest continent. The island is home to over 55 species found nowhere else on earth, including four unique land-birds.

Arriving at Henderson Island

On 22 May 2015, the RSPB expedition team arrived on Henderson Island after a smooth sail from Pitcairn Island. After two strenuous days of unloading research equipment from the supply ship, the team started work to better understand the ecology of this remote and rarely visited island.

Photo of Henderson Island by Andrew MacDonald (rspb-images.com)

Getting to know the rats

Henderson’s unique biodiversity is currently under threat due to the presence of introduced Pacific rats. One of the key goals of the 2015 expedition is to get a better understanding of the density and movement ranges of rats on the island. The team cut several trails and deployed 250 rat traps on the island, and started catching rats and marking them with numbered ear tags. Frequent recapture of individually identifiable rats will provide information on movement ranges and survival rates.

Monitoring the birds

The team also started monitoring the four endemic landbird species (Henderson fruit-dove, Henderson lorikeet, Henderson rail and Henderson reed-warbler) on Henderson to assess whether populations have changed in the four years since the failed rat eradication attempt. All four species are present in seemingly healthy numbers, and the skies above Henderson Island are full of wailing petrel species getting ready to breed.

Photo of Henderson Rail (one of the four endemic landbird species) by Richard Cuthbert (rspb-images.com).

Monitoring the plants

Lorna, the team's botanist, has started collecting some of the island's plants and has erected a time lapse camera to monitor the island's flowering and fruiting patterns over time.

Over the next 3 months the team will collect more data on vegetation, landbirds, rats, and seabirds, before being relieved by another crew at the end of August.

The Henderson expedition is funded by The Darwin Initiative and David & Lucile Packard Foundation.

Find out more about our Henderson Island Restoration Programme

Henderson Newsletter 08 MAY 2015 Final.pdf