Satellite images this month show a harmful red tide algal bloom festering in the Gulf of Mexico-- mere miles away from the shorelines of Southwest Florida. But birds have been telling us this for over a month.
At the Clinic for the Rehabilitation of Wildlife, or C.R.O.W., on Sanibel, some birds were reacquainted with the outdoors in a wired enclosure last week.
Veterinarian Julia Hill was checking up on them.
“We have pelicans and cormorants out here right now," said Hill. "It has an in-ground pool with filtered water that we can give them as they recover and it lets them start to fly again and socialize prior to releasing.”
These are birds that naturally don’t often make a lot of noise. However, these silent birds act as an alarm, signaling that something isn’t right in the environment.
Last month, the rehab center got an influx of sick pelicans and cormorants.
“They couldn’t move around very well," Hill said. "They looked like they were drunk.”
The birds had gastrointestinal problems, trouble breathing. Some were coughing up blood.
Hill said those are symptoms of exposure to red tide. But when these birds started coming in back in October, there were no indications of red tide from satellites or from instruments used to detect it.
“There were all zeroes right around here we we weren't even sampling. We were looking at our samples for phytoplankton. we weren't seeing any of the Red Tide cells,” said Bartleson as he cast a net to catch phytoplankton--the microorganism responsible for algal blooms like red tide--on Sanibel's Gulfside City Park Beach.
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Based on the reports from C.R.O.W. and recent satellite images, showing a growing bloom in the Gulf, scientists like Bartleson have been doing more monitoring.
He says red tide is often difficult to catch with the naked eye.
“The discoloration of the water the Red Tide is hard to see wherever there are reddish water,” Bartleson said.
The Caloosahatchee River’s water is a reddish brown. And the waterways it bleeds into, like Sanibel's coast, are often the same color.
He said satellites are sometimes slow in detecting it, because the red tide can be deeper than spectroradiometers can detect. Or the bloom may be living in other organisms.
“When there's a high red high concentration, that red tide also changes the other phytoplankton," Bartleson said. "And it reduces the number of other plankton.”
And, he said, it’s like a negative food chain reaction. Bigger organisms that feed on smaller organisms that rely on phytoplankton lose their energy sources.
So, red tide doesn’t only affect birds. It affects shrimp and turtles. Oyster and mussel harvesters have to shut down if the bloom gets too bad. Fish can get the stuff in their gills where it paralyzes their respiratory system. Manatees also can die from red tide.
Birds are the least likely to die from it And they’re usually able to make it to shore where they can easily be observed.
Red tide can also impact human health.
“If you wanted to smell it, then you could go to Captiva,” Bartleson said.
He said that if the wind is blowing towards the shore, carrying the toxins of a red tide bloom, and a human breathes it in, it could cause respiratory problems and can cause skin irritation.
“Stopping the red tide wouldn't probably be possible," Barleson said. "But reducing the intensity of the red tides and reducing the duration of the red tides could be possible.”
He said that since nutrients, like nitrogen, phosphorous and iron, fuel red tides, an effort can be made to have more treatment of the wastewater that ends up in the ocean. Bartleson said Maryland used to have the same problem.
“They reduced nutrient loadings from huge sewage treatment plants along the Chesapeake Bay and the Susquehanna River from Pennsylvania down to Maryland," he said. "And that lowered the nutrient concentrations and the Chesapeake Bay. And that can that reduced the intensity of their harmful algal blooms.”
When asked why Florida hasn’t followed that example, Bartleson said:
“Because it's Florida. We don't have the political will in Florida to do things like that.”
Back at the Clinic for the Rehabilitation of Wildlife, Veterinarian Julia Hill said it’s almost feeding time.
“They're just getting fed a lot of fish to make sure that they're in good condition before they're released,” she said.
The hope is that when these cormorants and pelicans are released back into the wild, they won’t end up getting exposed to red tide again.
But weekly updated data shows that the red tide algal bloom is only getting bigger.