Summer with the Least Terns

Summer has kicked off here at Fort Matanzas, and while the community enjoys the sunny beaches and soft sand, the Least Terns are on high alert, ready to protect their nests. These remarkable birds, often seen guarding their nests along the coastal dunes of St. Augustine, are colonial nesters. They begin arriving in the spring, around late March and early April, and their courtship rituals are a delightful sight. Male terns catch small fish and showcase them to potential mates. If a female accepts the fish, the pair will stay together for the rest of the breeding season. If not, the male continues his efforts until he finds a suitable fish and an accepting female.

Least tern brooding
Least tern chick (downy)
Least tern guarding the nest
Section of Least Tern colony

Every Thursday, a bird survey is conducted by two individuals who count the nests, least terns, chicks, and colonies. Prior to the survey both individuals prepare the “turtle bag” for the survey, which involves packing binoculars, new post signs, twine, and other helpful tools. If a post is seen to be damaged or just looking a little funky, the bag should have everything needed to fix the post. The data collected on these trips is meticulously documented both digitally and physically, allowing multiple departments, including Florida Fish and Wildlife Conservation Commission (FWC), to track colony size and trends. The most recent counts revealed about 16 nests along the south end of the island near the Matanzas Inlet. A concerning low for the season as typically nest numbers are much higher.

Wildlife Area Post

Kurt Foote, the Natural Resource Management Specialist at Fort Matanzas, has been actively combating storm erosion and human disturbance, which threaten the Least Terns’ nesting grounds. These birds prefer areas that shelly, sandy, and relatively flat – ideal for their cream-colored, speckled eggs that camouflage perfectly with the sand. Their nests are shallow divots in, created with minimal effort, similar to a light scrape of the sand.

Two least tern eggs

The Least Terns’ colonial nesting behavior is a crucial survival strategy. Larger colonies have a higher chance of successful nests because the birds collectively protect their territory. They are known to aggressively defend their nests, dive-bombing, defecting on intruders, and emitting high-pitched angry calls. A higher number of protectors means predators like raccoons, snakes, and crabs are less likely to reach their nests.

To mitigate the impacts of climate change and human encroachment, Kurt (with the help of interns) and the FWC have established perimeters around the colonies to keep people off the dunes and nests. Unfortunately, some individuals ignore these barriers, causing stress to the birds and sometimes leading to nest abandonment. When the terns are distracted by one threat, their nests become vulnerable to others, such as a sneaky ghost crab that seizes the opportunity for a quick meal. In the past, least terns adapted by nesting on flat gravel rooftops. However, modern roofing designs have made this option scarce in St. Augustine. Additionally, shoreline erosion caused by hurricanes, nor’easters, and other storms has reduced the amount of available nesting space. This creates a conflict between beachgoers and birds, as the reduced shorelines bring the two together, which is not ideal for either party.

Intern getting dive-bombed by tern colony
Beach in front of colony

As hurricanes become more frequent and the local population continues to grow, volunteers and staff members remain dedicated to protecting these beautiful birds. The Least terns travel hundreds of miles from South America to the shores of St. Augustine for just a few months each year. It is crucial that we provide them with the space that they require during this short period. By respecting the nesting areas and supporting conservation efforts, we can help ensure that the birds can continue calling Fort Matanzas home. 

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