INDIAN SHORES — Under sherbet-colored condo towers on a cordoned off chunk of beach, black skimmers carry fish to their chicks.
The babies, like balls of lint with beaks and feet, waddle around the sand. Beside them, bait fish look big.
Holley Short worries.
A patchy Red Tide bloom is drifting through the gulf and Tampa Bay. Dead fish — grunt, mullet, pinfish, trout and others — have been reported from Port Manatee to Honeymoon Island. The suspected culprit is toxic algae.
“The big concern is what are the parents feeding the chicks?” said Short, the Tampa Bay area shorebird project manager for Audubon Florida.
Standing several yards from the nests, she cannot tell whether the fish clutched in skimmers’ distinctive red and black beaks are alive or dead, healthy or sick. Toxins may be passing from the fish to the birds. Nesting season is a vulnerable time for new skimmers, but algal blooms can hurt Tampa Bay’s other shorebirds as well.
“It’s just moving higher up the food chain at this point,” Short said.
For people, Red Tide is typically only a nuisance. When bloom levels were detected earlier this month, Short felt the telltale signs: an itchy throat, nagging cough, watery eyes and a runny nose. But for animals in the water and on the shore, a bloom can be fatal.
Water sampling has detected elevated levels of the organism in Red Tide near black skimmer colonies, including last week near Three Rooker Island. They are considered a threatened species by the state and are known for how they touch their bills to the surface of the water to snap up food while flying.
Audubon volunteers have not noticed an obvious trend of skimmers falling ill during the bloom, Short said. But she fears that if Red Tide lingers, especially in a year she already considers bad for colonies because of beachgoers disturbing them, the skimmers could suffer.
“Birds are commonly affected when we have Red Tide,” said Leanne Flewelling, a section leader at the state’s Fish and Wildlife Research Institute who specializes in harmful algal blooms. “In fact some of the birds — not shorebirds but birds like cormorants that feed coastally on fish offshore — often they’re the sentinel that there’s a bloom out there.”
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Red Tide toxins can accumulate in shellfish, Flewelling said, and in the organs of other species.
Behind the Indian Shores nesting ground, the Seaside Seabird Sanctuary said that by Thursday it had received 49 birds showing signs of toxicity over the prior three weeks.
The Sanctuary said in a statement that birds surviving 24 hours after they are brought in tend to recover, “but it depends heavily on how long the birds have suffered from the toxicity before beginning treatment.”
“With the unpredictable nature of these blooms, our hospital expects to continue to see an influx of sick birds throughout the summer,” the Sanctuary said. “Even when the blooms dissipate, many food sources remain contaminated with the brevetoxin, and birds will continue to become affected for extended periods.”
Many shore species, including pelicans and terns, can be sickened by Red Tide toxins, said Breanna Frankel, rehabilitation manager at the Clinic for the Rehabilitation of Wildlife on Sanibel. They show up with heads like “limp noodles.”
“They kind of look like they’re walking around drunk, going in circles,” Frankel said. At some point, they could lose the ability to use their legs. “A lot of these birds, they could just be flying one day and after they take that last flight, there’s no getting back up in the air.”
When they land, if the birds are not around people who can get them help or take them to a sanctuary, they may starve and die.
A Clinic for the Rehabilitation of Wildlife spokesperson said in an average year, 4 to 6 percent of its caseload is connected to the algae. That number is a little under 10 percent so far in 2021.
Red Tide also affects other animals, including sea turtles, manatees and dolphins.
Short, of Audubon Florida, said black skimmers face enough problems in Pinellas, like competition for space on packed beaches and other animals stealing or eating their young. Mother and father skimmers take turns incubating eggs.
Independence Day is generally a rough time. Booms from fireworks cause skimmers to flush, or fly up, leaving their nests exposed. Short said she hopes people opt for sponsored displays this year over amateur beach blasts.
“Can we give them just a little break during July 4?” she said.