Joy riders and trespassers this summer have been destroying nests of a federally endangered bird on islands and sandbars of the Ohio and Mississippi rivers.

People riding off-road vehicles in protected areas destroyed numerous nests of the interior subspecies of the least tern in recent weeks. Yellow signs  posted prominently at each location identify it as a least tern nesting site and warn against trespassing. “This is clearly a case of people ignoring the signs and having no regard for the wildlife utilizing this sandbar,” said John Brunjes, migratory bird biologist with the Kentucky Department of Fish and Wildlife Resources. “The smallest intrusion on these islands can be fatal for the birds, let alone riding all over the island with vehicles.”

 Least terns are small, sparrow-sized birds that begin nesting on open sand and gravel islands or sandbars as soon as water levels in the rivers drop low enough to expose these areas in summer. Birds lay a clutch of eggs directly on the ground. The tiny eggs and chicks that emerge from them are remarkably camouflaged to match the coloration of the sand. They are easily overlooked.

Only 10,960 of these birds were found in a survey of 770 miles of the lower Mississippi River in 2005. Approximately 10-15 percent of this population nests in Kentucky. Least terns form nesting colonies of 10 to 400 pairs in Kentucky. The birds’ populations have declined because of habitat loss and disturbance.

Because islands emerging in the Ohio and Mississippi rivers are so small, any human presence may cause nests to fail. Temperatures in the sand may exceed 120 degrees on a summer day. Disturbance that keeps adult birds away for even a few minutes means almost certain death for the eggs.  Additionally, if chicks are present, they may jump into the water to escape intruders and be swept away by the river. 

“Simply landing your boat on these islands may keep adults off their nests causing the tern eggs or chicks to die within a matter of minutes,” said Brunjes. “Too much disturbance may cause the birds to abandon the site altogether.”

To protect this species, the Kentucky Department of Fish and Wildlife Resources warns off-roaders not to use islands posted as least tern nesting areas. Boaters also should not land on these islands or wander around them.

“It is illegal to operate recreational vehicles on these areas,” said Colonel Robert Milligan, chief of law enforcement for Kentucky Fish and Wildlife. “These areas are posted and violators will be cited for trespassing and cited for violating the Federal Endangered Species Act.”

Destroying a least tern nest can trigger a maximum federal fine of $100,000.

Not every island may be posted because low river levels have caused islands to appear that are not normally present. If you find small white birds swarming overhead, you may have found a nesting site. Please leave this site as quickly as possible.

Your cooperation will help Kentucky Fish and Wildlife ensure the presence of this species in Kentucky for years to come. To see a “Kentucky Afield” television video on least terns, visit YouTube.com on the Internet, searching under the keywords, “least tern nests.”

The Kentucky Department of Fish and Wildlife Resources manages, regulates, enforces and promotes responsible use of all fish and wildlife species, their habitats, public wildlife areas and waterways for the benefit of those resources and for public enjoyment. Kentucky Fish and Wildlife is an agency of the Tourism, Arts and Heritage Cabinet. For more information about the department, visit our web site at fw.ky.gov.