BEST funding secures a brighter future for the Wilkins’ bunting

Photo: Wilkins bunting in a Phylica tree © Ben Dilley

September 2018

At just 3.2km2 Nightingale Island is the smallest of the four islands that make up the Tristan da Cunha archipelago in the South Atlantic. Despite its small size it hosts more than a million breeding seabirds annually and is home to two endemic land birds found nowhere else in the world: the Nightingale bunting (Nesospiza questi) known locally as ‘Little Canary’; and the larger Wilkins’ bunting (Nesospiza wilkinsi) known as the ‘Big Canary’.

Wilkins’ Buntings - listed as endangered in the IUCN Red List - are found primarily in Phylica woodland and forage on the Phylica fruits which are an important component of their diet. Without the Phylica woodland habitat this highly specialised and endangered species would likely suffer serious declines and potentially face extinction.

Managed by the Tristan Conservation Department and funded by the European Union’s BEST 2.0 programme, the ‘Forest Restoration and Improved Biosecurity on Nightingale Island’ project collected data to provide a better understanding of the population and ecology of the Wilkins’ bunting. The project also initiated a programme for the restoration of Phylica woodland, established a nursery on the island for growing Phylica plants from seedlings to saplings, and developed a biosecurity protocol to prevent non-native species from reaching the island in the future.

The work done during two summer field seasons on Nightingale Island between June 2016 and July 2018 led to two important findings:

  • Prior to the project it was thought that there were approximately 50-80 pairs of Wilkins’ buntings on Nightingale Island, however, the data collected indicate that the true number could be almost double this.

Photos: Wilkins bunting eggs; Wilkins bunting nest; Wilkins bunting © Ben Dilley

  • Copses of Phylica trees heavily infested with the invasive brown soft scale Coccus hesperidum and the associated sooty mould Seiridium phylicae were discovered. The presence of this fungus on Nightingale could have a significant impact on the Wilkins’ buntings, as both their food source and primary nesting habitat could be negatively affected.

Photos: Invasive soft brown scale insect & sooty mould © Ben Dilley

These findings have important implications and will be used to inform future policy and management decisions for Nightingale Island. The Tristan da Cunha community and Conservation Staff will continue to care for the nursery, out-plant the seedlings to create new Phylica woodland habitat and closely monitor the extent of the newly discovered brown soft scale invasion to limit any negative impacts.

Thanks to the important work done through the BEST 2.0 project the future is looking positive for Nightingale Island and the Wilkins’ bunting.

Project factsheet – Forest Restoration and Improved Biosecurity on Nightingale Island