Livers were shriveled, muscles resembled cooked celery, guts held sand from desperation foraging and none were pregnant.
Those findings from dead manatees, starved by pollution-triggered eradication of their seagrass diet, came this week from state veterinary scientists.
At the same time, a report from the Marine Resources Council depicts water quality and clarity along Florida’s Atlantic coast as improving slightly amid the urgent campaign of environmental restoration, but the last traces of seagrass continue to perish and little is sprouting again.
Leesa Souto, executive director of the group, focusing on the health of Florida’s coastal Indian River Lagoon, said that with current technology it could take a half-century of laboring to replant lost seagrass.
Recovery of seagrass must occur naturally to rescue manatees, Souto said. “We’ve got way too many questions about why the seagrass isn’t coming back.”
A state agency responsible for the Indian River, the St. Johns River Water Management District, agrees water may be improving while seagrass isn’t.
“A substantial increase in acreage of seagrass after one period of clear water would not be expected,” said district scientist Chuck Jacoby. “We would probably need several growing seasons with good conditions to see that kind of increase.”
The upshot is that the wildlife disaster unfolding last year and so far this year, triggering an emergency and experimental feeding of the animals with lettuce, threatens to continue indefinitely.
In some areas, “the lagoon cannot support any manatees anymore,” Souto said. “They are dying by the dozens every week.”
Last year’s statewide deaths set a record at more than 1,100, with a third in Brevard County – where this year’s pace is still higher.
Martine de Wit, a veterinarian scientist at the Florida Fish and Wildlife Conservation Commission, said starvation was documented or suspected in more than 90% of nearly 350 dead manatees examined in January and February.
Their emaciated condition has been an ongoing reminder of the harrowing plight of manatees clinging to life along the state’s east coast.
“We are looking at the dead ones and we always say don’t forget about the live ones that are out there and will continue the population,” de Wit said.
She said the wasting away of manatees, with symptoms varying from atrophied testes to adult 15-pound livers receding to as little as 9, poses deep uncertainty about their future.
“A lot of those that stay in the Indian River all summer, those are not in good condition. I would be surprised to find normal pregnancy rates in those animals,” de Wit said. “There is so much that we have to wait for to really prove, to have the evidence for.”
Manatees have taken on a lore of toughness for their ability to heal from terrible wounds carved by boat propellers.
But they are not invulnerable, as de Wit and other scientists learned from deaths of more than 200 manatee occurring from 2012 to 2019 in the Indian River.
During that period, its waters were invaded by microscopic algae, as well as macroalgae, often known as seaweed. After years of examinations, scientists determined that manatees turning to seaweed for foraging could succumb to a toxic reaction and infection so swiftly they drowned.
“But, for chronic wasting, they can last quite a while,” said de Wit, estimating their drawn-out suffering can go on for a year or more.
Their bodies flatten, skin loosens, skeletal structures become visible and necklines recess, leaving the animals with a “peanut head” profile.
Manatees have two, extremely muscular diaphragms that manipulate air within their torsos for buoyancy control. De Wit said emaciation of those muscles leaves them unable to navigate or hold a position well.
“Manatees are trying to find energy and if they do not get that through nutrition, then they start depleting their body,” de Wit said.
The celebrated marine mammals present a face for an environmental tragedy but the root trouble is the plight of seagrass, the underwater wilderness of food and shelter for an astounding array of sea life.
Souto said the loss of more than 180 square miles of seagrass in the Indian River, an area nearly twice the size of Orlando, has been blamed widely on decades of septic systems, sewage spills, stormwater and other organic pollution.
That pollution feeds harmful growths of microscopic algae, which blocks sunlight that would nourish seagrass.
“However, seagrass is dying in areas with clear water,” states a Marine Resources Council report card issued Thursday. “That’s deeply concerning.”
State cuts in environmental funding after the recession more than a decade ago are especially punishing now for monitoring water quality, Souto said, contending that state tests are too infrequent, in too few places, with too much lag time and looking for too few signs of illness.
A prime suspect not under surveillance is the trend of replacing mechanical removal of aquatic weeds with the use of herbicides, particularly in canals, which may also kill seagrass, Souto said.
“Maybe there are no herbicides and wouldn’t that be fantastic but maybe there are,” Souto said. “What if it is herbicides?”
Her group is launching funding initiatives for costly herbicide and other testing, as well as hosting an assembly of seagrass experts for solutions.
However those steps play out, state and federal wildlife authorities already are looking toward next winter.
An emergency feeding of manatees, doling out 110,000 pounds of lettuce by hand since December, is winding down at a Florida Power & Light Co. electric plant south of Titusville.
The animals congregated in the plant’s discharge of warm water during cold snaps but are now dispersing with spring approaching.
“Starvation is a chronic condition,” said Tom Reinert, a regional director for the state wildlife agency. “Animals that have been debilitated but make it through this year, coming into next winter they may not be in the best of shape.”
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