Recently a Southern Giant-Petrel Macronectes giganteus was found by SANParks (www.sanparks.org) rangers on a beach in Nature’s Valley. Finding birds sitting on the beach is not necessarily a problem, depending on the species. When you find a species like this on the beach, there is no question, there is something wrong with it! Southern Giant-Petrels are large birds, with a uniform grey-brown body and slightly paler head. They have a very large flesh-coloured bill tipped pale green and a flesh-coloured nostril tube which sits atop the bill – quite an interesting sight! Southern Giant-Petrels are a deep-sea pelagic species which spend most of their lives at sea, coming to land only to breed. It is for this reason that when you see this species on land outside the breeding season and breeding colonies you know there is something wrong with it! You can contact Nature’s Valley Trust (www.naturesvalleytrust.co.za).
Unfortunately, the primary threat to this species at sea is human related. Longline fisheries catch Southern Giant-Petrels as bycatch. Fortunately, a number of mitigation methods have been able to reduce the number of deaths. Currently, this species is listed as Least Concern on the IUCN redlist, with an increasing population. Southern Giant-Petrels first breed at an age of 10 years, and live for over 50 years. Adult breeders tend to stay in the ocean surrounding their breeding site, while juveniles are more likely to disperse further afield. These birds are known to feed on carrion, and offal and refuse from ships, as well as cephalopods, fish, and other birds. Interestingly, males and females show spatial segregation in their foraging ranges and males will chase females from a feeding site.
Written by: Minke Witteveen
For further reading:
- BirdLife International. 2012. Macronectes giganteus. The IUCN Red List of Threatened Species 2012. Accessed: 2016-06-18. URL: http://www.iucnredlist.org/details/
- Branch, G.M., Griffiths, C.L., Branch, M.L. and Beckley, L.E. 2010. Two Oceans: A guide to the marine life of southern Africa. Pp. 358. Random House Struik Publishers, Cape Town.
- Stander, Y. 2016. Swift cooperation ensures a bird is saved. Knysna-Plett Herald. Accessed: 2016-06-18. URL: http://www.knysnaplettherald.com/news.aspx?main=