Climate Change Threatens Seabirds on Both Land and Sea

Seabirds are often the first thing we see and hear on the coast. These iconic birds like terns, Black Skimmers, or Ospreys and Brown Pelicans nest along our coasts on barrier islands, rocky cliffs, beaches, and marshes. To feed themselves and their chicks, they rely on a diet of fish from the ocean. But climate change brings a triple-threat to the ocean—rising temperatures, sea-level rise, and ocean acidification—all of which is already affecting these seabirds throughout their life cycle.

Since the 1970s, the ocean has absorbed 90 percent of the warming and a third of carbon dioxide from increased carbon emissions. If the ocean didn’t absorb almost all of the excess carbon dioxide, average global temperatures would be 35°F hotter. Unfortunately, the ocean can only absorb so much. And according to a new study, sea-level rise is one many threats that climate change poses to birds across 90% of the United States.

As sea levels rise, coastal birds have lost safe, healthy coastal areas to nest. Extreme high tides are already flooding out the nests in Connecticut where Saltmarsh Sparrow chicks struggle to keep their heads above water. Low-lying islands like those in the coastal Carolinas will soon be underwater and unable to support the terns and Black Skimmers that nest directly on the bare sand.

Hotter, more acidic ocean waters also make it difficult for seabirds to find a meal. Seabirds rely on small, schooling fish like sardines and anchovies, known as forage fish. As the ocean heats up, forage fish travel further offshore to colder, more productive waters, which in turn means that seabirds must work harder to find them. The shells of tiny plants and animals called phytoplankton and zooplankton will also dissolve in an acidic ocean—as they decline, so too will forage fish and seabirds in turn, creating a ripple effect in the ocean food chain.

All of these issues are fixable with a robust climate policy that reduces emissions as well as the additional stressors that coastal birds face. To address sea-level rise, we must protect and restore our coastal ecosystems like wetlands, oyster reefs, seagrass beds, and barrier islands. These areas benefit birds and people by absorbing excess water, buffering against rising seas and coastal flooding, all while also acting as “carbon sinks,” storing carbon pollution in their vegetation. The restoration of a historic pelican nesting island in Louisiana, for example, has rescued the island from inundation and provided healthy habitat for thousands of Brown Pelicans, Roseate Spoonbills, and Reddish Egrets to nest.

To boost forage fish for seabirds, we must change the way we manage our fisheries. Forage fish are threatened by climate change and commercial harvest that grinds these small fish up to produce fertilizer, cosmetics, fish meal, and more. Our only federal fisheries policy, however, the Magnuson-Stevens Act, does not take into account the huge role they play as the foundation of the ocean ecosystem or how warming waters affect their populations. Updating this law to factor in the needs of seabirds and the effects of climate change is essential to healthy ocean predators such as seabirds.

Without action, we stand to lose not just seabirds, but our coastal economy—from fishing to eco-tourism based companies—and the coastal communities that 40 percent of U.S. residents call home. Speak up for seabirds—write to your legislators and urge them to address the threats they face due to climate change.