DPLUS018 – Taxonomic and Conservation Status of Oceanodroma Storm Petrels in the South Atlantic

Storm Petrels are the least well known species of the seabird grouping on St Helena and Ascension and have traditionally been viewed as conspecific with Oceanodroma Castro which is widespread throughout the North Atlantic and Pacific. The conservation status of the Storm Petrels of St Helena and Ascension crucially hinges on a correct understanding of their taxonomic affinities with other Atlantic and Pacific populations of Oceanodroma storm petrels. This project was put into place to clarify the conservation status of the two seasonal populations of Storm Petrels on Ascension and St Helena.

This project involved large amounts of training to staff to ensure the conservation and management of the South Atlantic Oceanodroma populations is continued past project as they were thought to be endemic to St Helena and Ascension. The teams had to make genetic comparisons with existing data from North Atlantic and Pacific populations, and employ new techniques to survey the seasonal populations on both St Helena and Ascension by long term monitoring. However, the South Atlantic population of Oceanodroma Storm Petrel did appear to be genetically, physically and vocally significantly different to the other Oceanodroma populations globally. Queens University then undertook Mitochondrial and Microsatellite analysis. Further analysis of the Morphometric, vocalisations and vocal recognition data supported the DNA analysis which suggested that the four seasonal populations of Oceanodroma Storm Petrels from Ascension and St Helena formed two groupings, one on each Island. At Egg Island (St Helena) and Boatswain Bird Island (Ascension) estimations were made of the Storm Petrel breeding population size. This however, still didn’t give the team’s sufficient information. Automated sound recorders were then bought to identify other areas where the Storm Petrel breeds. St Helena’s failed to accurately positively detect these birds vocalisation. Manual screening was the only way they could be identified. This identified one new potential colony on St Helena’s coastline for the breeding of Storm Petrels.


Our Project Partners

Ascension Island Government Conservation Department (AIGCD)


Conservation efforts on Ascension were formally initiated in 2001 when the Foreign and commonwealth Office (FCO) funded a seabird restoration project that was managed by the Royal Society for the Protection of birds (RSPB). Since then the Ascension Island conservation team had made steady progress in conserving and promoting the island’s fantastic biodiversity. Ascension has a poor biodiversity due to its isolation but despite this the degree of endemism of terrestrial and marine biodiversity is high, with at least 55 endemic species of fish, plants and invertebrates. Ascension Island also supports the largest green turtle and seabird nesting colonies in the tropical South Atlantic. Working with our partners we carry out practical conservation and also a number of research projects.  If you would like any more information about our work or working with us then please do not hesitate to get in touch (conservationenquiries@ascension.gov.ac)

Royal Society for the Protection of Birds (RSPB)


We want to celebrate our legacy and create a movement- to make nature, and its conservation, a fundamental part of everyone’s lives. We want to nurture a world where it’s part of everyone’s automatic thinking to let nature in and not shut it out. As part of this, we will continue our work to enable and empower everybody, to be able to connect to nature and become guardian to it. We’re all in this together – and together we have the power to collectively change the fate of nature, creating a new balance and rediscovering our place in the nature world again


St Helena National Trust (SHNT)


The St Helena National Trust is an independent not-for-profit organisation which aims to preserve St Helena’s environmental and cultural heritage. The St Helena National Trust hopes to promote the appreciation of St Helena unique environment, to acquire and hold the natural beauty of our Island, to give the people of St Helena a stake in the future of our unique environmental and cultural heritage and to provide opportunities for enjoyment, education, recreation and spiritual refreshment.