Tracking Reveals Sandwich Tern's 4,000-Mile Journey to Peru
New satellite data from Audubon North Carolina documents the precise migration route of a Sandwich Tern from its breeding grounds to a Peruvian wildlife
For the first time, researchers have documented the exact migration route of a Sandwich Tern from North Carolina to the Pacific coast of South America. The bird's four-month journey ended at Peru's Paracas National Reserve, a 335,000-hectare marine protected area.
The discovery comes from a tracking partnership between Audubon North Carolina and Dr. Kate Goodenough, lead ecologist at Larid Research and Conservation. Five Sandwich Terns were fitted with transmitters at their breeding colony on Ferry Slip Island in the Cape Fear River. The data reveals where these birds go for half the year, information vital for hemispheric conservation efforts.
A Tern's Transcontinental Route
While banding studies had previously indicated terns wintered in South America, the satellite tracker mapped the precise path. One individual traveled south along the coast last fall, passing Honduras and Panama before crossing to Ecuador and finally Peru.
The tern was drawn to the Paracas reserve by the nutrient-rich Humboldt Current. This cold underwater highway collides with the reserve's coastline, pushing nutrients to the surface and creating a rich foraging ground. "The reserve is an extremely important stopover and staging area for a great diversity of long-distance shorebird migrants," said Dr. Goodenough, noting the North Carolina tern is now among them.
Royal Tern Habits and Site Fidelity
Concurrent research on Royal Terns has yielded three seasons of tracking data from 21 birds. Their migration destinations varied widely across the hemisphere.
A key finding emerged this year: four Royal Terns returned to the exact same wintering locations for two consecutive seasons. Dr. Goodenough called this wintering site fidelity an exciting discovery. It shows the importance of conserving specific sites across the hemisphere for the birds' continued use.
The Imperative for International Collaboration
The research starkly illustrates that local conservation is insufficient for migratory species. Audubon notes the terns spend only about six months in North Carolina. The other half of their life cycle depends on habitats in Central and South America.
"This research has underscored the importance of stopover and foraging areas for migrating waterbirds," Goodenough stated. She emphasized that their survival requires international attention and collaboration. Audubon frames this as a hemispheric approach, working with partners like Conserva Aves to protect habitat across the birds' entire migratory range.
The data from the fast-moving terns has opened a world of new discoveries. It provides a concrete map for conservation action, aiming to protect the birds on both sides of their incredible journeys.
