Ocean Sentry
(From theaustralian.news.com.au)- Tens of thousands of seabirds are failing to breed because warmer water from more frequent and intense El Nino events means there is insufficient food to raise their young, according to research compiled by the Great Barrier Reef Marine Park Authority. Warm water near the surface forces fish, plankton and other prey into deeper water, where it cannot be reached by seabirds.
“Recent analyses at key sites have revealed significant declines in populations of some of the most common seabird species, which raises concerns regarding the threatening processes acting on these populations,” says the report, prepared by C&R Consulting.
The report, Seabirds and Shorebirds in the Great Barrier Reef World Heritage Area in a Changing Climate, says the reef is home to between 1.3 and 1.7million seabirds and half the world’s population of several species.
The results of research by Bradley Congdon and five other seabird experts working for the marine park authority have been published in another report, Climate Change and the Great Barrier Reef: A Vulnerability Assessment.
The authors concluded that recent climate fluctuations were having significant detrimental impacts on seabird populations.
On Heron Island, the black noddy population had been rising since early last century, but the number of active nests fell from about 70,000 to 30,000 between 1996 and 2000, with mass mortality of adults and chicks in the El Nino year of 1998.
On the Swain Reefs, in the southern reef, the number of brown booby nests has dropped from 350 in 1975 to less than 30 since 2000.
(By Greg Roberts and Sean Parnell)
