At the peak of Florida’s red tide crisis this summer, Jon Peterson had to dig deep into Sea World’s storage warehouses to find enough portable pools to accommodate the dozens of sick manatees arriving at a rate of two or three a week.

The Orlando theme park’s manager for animal rescues even found himself forking out for air fares to send some of his younger manatee patients off to zoos in Ohio to free enough space in the rehabilitation centre for the newest victims of the toxic algae phenomenon that has killed thousands of fish and marine mammals.

Toxic 'red tide' blamed for rise of manatee deaths in Florida Read more

It was, Peterson says, “the roughest red tide we’ve had in a long while”, testing to the limit the capabilities of the Sea World facility and the many other essential components of a fragile network of foster care for Florida’s distressed sea life in times of emergency.

Now, with red tide blooms still creeping along areas of the state’s west coast in high concentrations, according to the latest water samplings from the Florida fish and wildlife commission (FWC), there has been little let-up in the pressure on the marine parks, zoos and aquariums that continue to respond to the crisis a year after its outbreak.

Pool space is scarce for newer arrivals of affected manatees, dolphins and sea turtles. Staff and volunteers who rescue, treat, rehabilitate and release animals are working long hours with limited resources to save as many as they can.

“Right now it looks like it’s moving south again. We just have to work with it and care for every manatee,” said Peterson, who says Sea World alone has taken in 66 manatees this year, 15 of which have tested positive for the naturally occurring Karenia brevis organism that causes red tide. Currently, he said, 31 manatees were still in the rehabilitation centre.

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“We’ve had so many animals coming in. I’m nearing the upper limit, but we’ll do whatever it needs,” he said.

Perhaps the most important relief valve is Sea World’s partnerships with Columbus zoo and aquarium and Cincinnati Zoo’s Manatee Springs.

“Both opened their doors this year because of the need and said we can take a little bit more than we’re normally set up for,” Peterson said. “We sent five earlier in the year. They house them for six months to a year or sometimes two years depending on the animal’s age and needs.”

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The stresses of one of the worst red tides in living memory have been felt up and down the chain of federal and state agencies, marine research facilities and private operators such as Sea World, the Miami Seaquarium and Clearwater Aquarium that form the frontline of crisis response.

Adding to the challenge has been the year-long closure for refurbishment of the David A Straz Jr manatee critical care centre at ZooTampa.

“There was no choice, they had to get their tanks fixed,” said Martine de Wit, lead veterinarian at FWC’s marine mammal pathobiology laboratory in St Petersburg, which coordinates the rescue and collection of sick and deceased marine life across the state’s south-western region.

“When we get to a manatee often we get help from locals, those who reported it. They’ll sit there for an hour supporting the manatee, keeping its head up out of the water to make sure it can breathe.

“It really takes a lot of effort to coordinate and get it all figured out. These are the cases that can push our system over the edge.”

A glance at FWC’s manatee mortality figures reveals the severity of this year’s red tide crisis. Preliminary figures for the first 10 months of 2018 show 191 fatalities to confirmed or suspected red tide, in which the animals are poisoned when they eat seagrass coated with toxic algae, compared with 67 for the whole of 2017, and only 15 the year before.

The figures could even be higher. With live rescues taking precedence, De Wit says, her team cannot get to every dead manatee. “In many cases the carcasses are too decomposed and this year because there are so many we’re also having to leave many without a necropsy,” she said.

At Sarasota’s Mote marine laboratory and aquarium, teams have recovered 22 Atlantic bottlenosed dolphins since 1 July, according to Gretchen Lovewell, manager of the facility’s stranding investigations programme, an unusually high number that contributed to the national oceanographic and atmospheric administration’s declaration in August of an unusual mortality event for dolphins in south-west Florida.

“We were working non-stop during the peak of the event, picking up a dozen turtles and sometimes three or four dolphins a day. We couldn’t have done it without our volunteers, people were coming out of the woodwork to help,” she said.

“Sadly for the turtles and dolphins, most are carcass recoveries. During the spike, from well over 200 turtles, only 15 were alive. The summer was hard, I’m not going to sugarcoat it, it was hell.”