On 2 May 2010 Scientific American reported that there is "the possibility of some oil beaching on the Chandeleur Islands ... and ... the Breton National Wildlife refuge". This would be very bad news for the Brown Pelican population of this area.
Breton National Wildlife Refuge
Theodore Roosevelt established this reserve in 1904, and actually visited it in 1915. It is home to many important breeding bird colonies, among them those of the Brown Pelican.
The refuge suffered badly when Hurricane Katrina swept past in 2005, and again in the same year when a small oil spill from a storm-damaged drilling platform was blown ashore. The hurricane destroyed many young pelicans at their nest sites, and the oil fouled the area killing many of those that were left.
U.S. Interior Secretary Ken Salazar has stated that the Deepwater Horizon accident could "leak 100,000 barrels of oil per day", making it much more serious than the 2005 spill.
Brown Pelican Nesting Sites
The nesting grounds of the Brown Pelican (Pelecanus occidentalis) within the Breton National Wildlife Refuge are a critical part of their habitat.
The pelicans are at their most vulnerable to oil fouling when nesting on the ground, but even those nesting in mangrove trees are dependent on nearby fish for survival. Young may leave the ground nest after 5 weeks, but those in the tree nests remain for an additional 2 weeks. Brown Pelicans nest in March and April, so the current spill could not have happened at a worse time for them. Many young birds are vulnerable.
The small spill in 2005 is thought to have killed around 700 birds, and the current oil slick will do much greater damage if it is blown ashore. About 1,000 pelicans are thought to have died in the cold winter of 2010, so the population did not enter this breeding season in very good shape, and the additional problem that oil would cause them could have a devastating effect.
Black Mangrove and Fisheries
The Black Mangrove (Avicennia germinans) is one of the common plants in the Breton National Wildlife refuge, and it is not only used by the Brown Pelican for nesting. The roots of the mangroves are very important in the life cycles of many fish and shellfish, so any oil fouling will have serious consequences for future recruitment to the fisheries.
Pelicans rely on the fish near their nests during the breeding season, so the present oil spill will harm them as well as impacting on human commercial fisheries.
Main references: 'Breton National Wildlife Refuge' - US Fish and Wildlife Service, and ' Fishing halted as Gulf oil slick threatens catastrophe ' - Scientific American, 2 May 2010.
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