Nesting shorebirds that historically laid their eggs right on the beach sand find it harder today to complete this annual ritual without human interference. With so many people and dogs on the beaches along the Gulf Coast, the birds will often abandon their nests when disturbed.
But manmade structures give them a slight reprieve from the crowds. Gravel rooftops, which look a lot like beach sand to least terns, American oystercatchers, and black skimmers, have become the nesting site of choice for hundreds of birds each year.
Audubon Florida staff and volunteers act as guardians for the rooftop nesters. The count the birds and look out for chicks that may fall off the roofs.
American oystercatchers will be the first to take up residence on gravel rooftops, beginning this week. The oystercatchers typically choose rooftops along the Intracoastal Waterway or near the beach. This way they can also be close to foraging areas during low tides.
Least terns and black skimmers will join in on rooftop nesting in April.
Preparing roofs for nesting shorebirds
Already, Audubon staff and volunteers are conducting breeding surveys and monitoring nest sites. They will continue to do so through August, once all the chicks have left the rooftops.
All told, there are 86 rooftops that Tampa Bay Region Biologist Kara Cook monitors for nesting activities. Most monitoring is done from the ground.
“I am already hearing from roof managers that they are seeing our earliest nesters, American oystercatchers, scouting out rooftops where they have nested previously to see if they want to nest there again,” Cook said.
“The least terns migrate to South American, so they will be returning soon and nesting by mid- to late April,” said Cook. She monitors rooftops in Pinellas, Hillsborough, Pasco, Manatee and Sarasota counties.
Last year 13 pairs of oystercatchers nested on gravel rooftops in the five-county area. This is the only area in the state where they are nesting on these rooftops. This is probably because of throngs of people visiting local beaches, Cook said.
“We are not 100% sure on that, but with our busy beaches, the loss of habitat due to coastal development and human disturbances, they don’t have quiet places to make nests and raise their young,” the biologist said.
For the least terns, which are much smaller, the likelihood of chicks falling from these rooftops is much greater. So, Audubon engages “chick checkers,” volunteers to visit nesting sites three to four times a day to look for chicks on the ground. They use long poles with bins on the end, called chick-a-booms, to gently scoop up the chicks and place them back on the roof.
The pros and cons of rooftop life
There are pros and cons to the birds abandoning the beach to nest on rooftops, Cook said. “One of the pros is that there are no predators like coyotes and racoons. There is no beach overwash” from high tides that can flood nests, and there is little to no human disturbance.
Cons include the chicks falling from the rooftops. Volunteers help place fencing around the gravel rooftops to avoid such falls. There are also avian predators, such as fish crows and hawks, who can swoop in and grab eggs and chicks.
“For the most part, though, they have been successful nesting on the rooftops,” Cook said. The fencing and shelters placed on the rooftops to give chicks a place to hide from predators.
Last year, Cook had 44 volunteers step forward to help as chick-checkers or to monitor rooftops to count birds. She could still use more, she said.
While chick-checkers are expected to visit rooftops three or four times a day, it does not have to be the same person. They can sign up for the time they want to go check on the nesting birds.
“It’s a great citizen science thing,” Cook said. “It is super helpful to have volunteers, since I’m driving to all of these sites every week.”
Anyone interested in joining this effort to monitor the rooftop nesters can become a bird steward by visiting fl.audubon.org/bird-stewards.