Open image gallery
The Sooty Shearwater Puffinus griseus is listed as globally Near Threatened due to an estimated rapid decline, owing to impacts from fisheries, the exploitation of chicks and possible impacts from climate change. The global status of this species is adopted as the regional status.
The Sooty Shearwater breeds on islands off South America, the Falklands, Tristan da Cunha, south-east Australia, Tasmania and New Zealand (Robertson et al. 2003). Birds disperse widely during the non-breeding season across the Southern Ocean and into the Pacific and Atlantic oceans, both north and south of the equator (Robertson et al. 2003). It is a non-breeding visitor to South African waters, where it is one of the most abundant pelagic seabird off the west and south coasts. It is fairly common off KwaZulu-Natal (Ryan 1997). Small numbers can occur anywhere in continental waters but the distribution of large flocks is linked to that of pelagic fish schools (Ryan 1997). It is a vagrant to the Indian Ocean north of 20°S.
The global population is extremely large and is estimated to be c. 20 000 000 mature individuals (Brooke 2004) with colonies on islands off New Zealand, Australia and Chile, and the Falkland Islands (Malvinas). New Zealand has c. 5 million pairs spread across 80 colonies (Marchant and Higgins 1990). In Australia, there are colonies on 17 islands (all less than 1 000 pairs) while southern Chile has a number of colonies with some up to 200 000 pairs (BirdLife International 2014) and c. 4 million birds on Isla Guafo (Reyes-Arriagada et al. 2007). The Falklands have 10 000-20 000 pairs (BirdLife International 2014). Within the region, populations over the continental shelf and shelf-break have been crudely estimated at c. 750 000 birds in winter and 320 000 birds in summer (Crawford et al. 1991). Confidence in the regional population estimate is low.
The global population is suspected to be in decline (Veit et al. 1997, Scofield and Christie 2002) although the exact rate of decline has not been established (BirdLife International 2014). Confidence in this trend estimate is low.
The primary threat to Sooty Shearwaters are pelagic drift-nets which drown up to 350 000 birds annually and, to a lesser extent, longline fisheries (Garnett et al. 2011). Birds have been recorded to have been caught by longline and trawl fishing operations in the region (DEAT 2008). The exploitation of chicks for human consumption accounts for c. 250 000 individuals per year (Newman et al. 2009). Rats have been shown to prey on chicks but the extent is unknown (Jones et al. 2008).
Albatross Task Force teams are working in eight countries (Peru, Uruguay, Brazil, Argentina, Ecuador, Chile and South Africa and Namibia) to reduce fisheries bycatch in local trawl and longline fisheries. Within the region the species is protected under the Sea Birds and Seals Protection Act, 1973 (Act No. 46 of 1973), Marine Living Resources Act (Act No. 18 of 1998): Publication of Policy on the Management of Seals, Seabirds and Shorebirds: 2007 and the National Plan of Action (NPOA) for Reducing the Incidental Catch of Seabirds in Longline Fisheries 2008.
As with other seabirds threatened by accidental bycatch through the fisheries industries, conservation measures for the Sooty Shearwater revolve around the application of appropriate mitigation measures, monitoring of results, and ensuring that there is continued education, training and publicity regarding mortalities suffered by bycatch.
* The impact that the regional trawl and longline fisheries have on this species should be monitored. Accordingly bycatch levels should be carefully documented in South African waters.