Bird sites most at risk from Gulf oil spill

Reddish egrets may struggle as they are slow breeders. Credit Gary Smyle.

May 2010. American Bird Conservancy (ABC), the USA's leading bird conservation organization, has released a list of key bird sites they say are most immediately threatened by the ongoing Deepwater Horizon oil spill in the Gulf. The sites have been previously designated as Globally Important Bird Areas by the organization, and are directly in the path of the advancing oil slick.

"This spill spells disaster for birds in this region and beyond," said ABC President George Fenwick. "It is ironic that next weekend is International Migratory Bird Day. At a time when we should be celebrating the beauty and wonder of migratory birds, we could be mourning the worst environmental disaster in recent U.S. history."

The effects will be felt right across the Americas
The Gulf Coast is extremely important for hundreds of species of migrants, which variously breed, winter, and rest here during migration. The population effects on birds from this spill will be felt as far north as Canada and Alaska, and as far south as South America.

The complexity of the Gulf coastline, with numerous bays, estuaries, inlets, marshes and creeks, will make cleanup extremely difficult; impacts could last for decades for much of the habitat, and some species may suffer significant long-term population declines.

"This spill tells us that we cannot take our coastline for granted. A re-assessment of our approach to offshore drilling is required in the light of this disaster that includes the development of no-go areas for oil," Fenwick said.

ABC has produced a map of the 500 Globally Important Bird Areas in the United States, 149 of which are coastal or have a coastal component that could be affected by this and future marine oil spills. A portion of these sites are in immediate danger from the Deepwater Horizon spill.

Snowy egret. Photo by Gary Smyle.

Environmental cost of energy production
"There are costs to wildlife and their habitats for every form of energy generation, whether it is coal, oil, wind, nuclear, or any other form. Those costs must be re-assessed, not by economists, industry, or energy experts, but by biologists, ecologists, and environmental experts. The stakes are simply too great to leave to chance. We must stop playing Russian roulette with the future of our environment," said Fenwick.

All coastal nesting species (herons, terns, skimmers, plovers, gulls, rails, ducks) are currently present on the Gulf Coast, including several species on the U.S. WatchList of birds of conservation concern. The impact to these species depends on how long the leak lasts and what happens with weather and currents. The leak could persist for weeks or months, and end up being the worst environmental disaster in U.S. history.

Species particularly susceptible to pollution
For species with long lifespans and low reproductive rates (e.g., Reddish Egrets, Least Terns), acute mortality events such as this can have long-term population-level impacts if they affect a large proportion of the breeding population. This is because the adults that survive do not produce young quickly enough for populations to recovery quickly.

Species where large proportions of their populations concentrate in a few, discreet locations (e.g., species with only a few breeding colonies and species that concentrate en masse during migration stopover) are particularly vulnerable to these events.

Compounding problems for songbirds, not normally directly affected by oil spills, is the smoke billowing skywards from the burning oil that was set alight to try to minimize damage to marine life.

"Millions of songbirds are crossing the Gulf now, and will arrive Stateside perilously weak and undernourished from their journey. The smoke may well compound their precarious situation and potentially lead to birds failing to make it to shore, or arriving so weakened that they are unable to survive," said Fenwick.