New Tracking Data Uncovers Sandwich Tern Migration Mysteries

Royal and Sandwich Terns have been nesting in North Carolina for many years, however little is thought about their foraging habits in the course of the breeding season, the route they take to get to their wintering grounds, or the timing of those actions.

That’s why we partnered with Dr. Kate Goodenough, lead ecologist at Larid Analysis and Conservation—to get a glimpse at their full annual life cycle, which can assist information conservation and restoration initiatives.

This 12 months, 5 Sandwich Terns returned to breed on the Cape Concern River with trackers able to transmit hundreds of information factors to the bottom station arrange on Ferry Slip Island, the place they spent this 12 months’s nesting season. Right here’s what they introduced again.

One tern’s journey to Peru

We all know that Sandwich Terns that nest on the east coast journey to South America for the winter due to our long-term effort to band chicks and doc resightings. However we’ve by no means documented the precise route these birds take to get to their overwintering locations. The info we collected this 12 months started to unravel these mysteries.

This was very true for one Sandwich Tern who slowly migrated south alongside the coast final fall in direction of Honduras and Panama, earlier than making the soar to Ecuador, and at last Peru. It spent the winter at Paracas National Reserve, a 335,000-hectare marine wildlife space concerning the dimension of Rhode Island.

“The reserve is a particularly essential stopover and staging space for an incredible range of long-distance shorebird migrants and now we all know that one among our North Carolina terns is amongst these guests,” Goodenough added.

It wasn’t likelihood that drew this tern to Paracas, however the nutrient-rich underwater present that makes this reserve some of the biologically numerous areas in Peru. Often called the Humboldt Present, this chilly underwater freeway flows northward alongside the Peruvian coast and collides with the Paracas Nationwide Reserve, pushing vitamins up in direction of the floor of the ocean.

This nutrient-rich water offers the proper foraging grounds for all types of wildlife, together with our North Carolina Sandwich Tern. The tern spent 4 months touring alongside the shoreline of Peru earlier than returning to our shores this spring.

The Return of the Terns

We now have three seasons of Royal tern monitoring information which has uncovered new particulars about their actions throughout breeding, migration, and overwintering. Of the 21 Royal Terns we’ve tracked to this point, seven returned to the breeding colony in 2025 and 9 returned in 2026.

Their migration routes assorted fairly a bit with some staying within the U.S. to winter in Florida and a few going to the Dominican Republic, Cuba, Mexico, Panama, and Colombia.

“One new discovery we made this 12 months was that 4 of our Royal Terns wintered in the identical areas for 2 consecutive seasons,” mentioned Goodenough. “That is an thrilling discovering and tells us simply how essential it’s to preserve websites throughout the hemisphere for his or her continued use.”

Due to the three years of information gathered from the backs of fast-moving Royal and Sandwich Terns, we’ve opened a world of recent discoveries that may assist us preserve these birds in North Carolina and past.

For the primary time ever we’ve documented

Royal Terns displaying wintering website constancy
The migration route of a Sandwich Tern from the Atlantic Coast of the U.S. (North Carolina) to the Pacific Coast of South America (Peru)

“This analysis has underscored the significance of stopover and foraging areas for migrating waterbirds,” mentioned Goodenough. “We solely have them in North Carolina for about six months and spend the opposite a part of their life in components of the world that require worldwide consideration and collaboration.”

Audubon acknowledges collaboration as a key facet of our hemispheric strategy to fowl conservation. That’s why we work with companions like Dr. Goodenough, to assist us perceive the panorama our birds depend on and advocate for insurance policies that enable them to thrive in each stage of life.

Audubon’s rising hemispheric attain and coordination with many companions at Conserva Aves is now working to guard habitat throughout the hemisphere, and possibly on either side of those terns’ journeys.

Discover the migration maps under for extra of our tracked birds.

Trending Merchandise