Three conservation groups moved toward filing a lawsuit against the U.S. Environmental Protection Agency over water-quality problems that have led to a record number of manatee deaths this year in Florida.

The Center for Biological Diversity, Defenders of Wildlife and the Save the Manatee Club filed a notice that is a precursor to suing the EPA. The notice said the EPA needs to start a process to reconsider whether water quality standards are adequate to protect manatees in the East Coast's Indian River Lagoon, where many of the deaths have occurred.

"In short, both the Indian River Lagoon and the manatee are presently in the midst of ecological collapse," said the notice, filed by attorneys for the Earthjustice law organization on behalf of the conservation groups. "Further, it appears likely that the 2021 unusual mortality event will not be a one-time event, but rather portends a grim future of continued manatee deaths unless more effective actions are taken to address the key environmental factor driving them — nutrient pollution of key estuary habitats that is destroying habitat, including food for manatees and many other species."

As of Dec. 10, Florida totaled 1,056 manatee deaths this year, according to data posted on the Florida Fish and Wildlife Conservation Commission website. The notice filed Monday by the conservation groups said this year's total is roughly double the average annual number of manatee deaths.

Wildlife officials say many of the deaths have been caused by starvation, as poor water quality has killed seagrasses that are a key food source for manatees. The situation has led wildlife officials to take the unusual step of starting to feed manatees.

In the notice Monday, the conservation groups said the EPA oversees Florida's development of water-quality standards and what are known as "total maximum daily loads," which involve maximum allowable amounts of pollutants in waterways. The notice alleges that the EPA is in violation of the federal Endangered Species Act for not starting a consultation process with the U.S. Fish and Wildlife Conservation Service to determine if current total maximum daily loads are adequate to protect manatees.

"The die-off of seagrass is directly related to deteriorating water quality in the Indian River Lagoon," the notice said. "As human development has increased around the Indian River Lagoon, so has the input of nitrogen and phosphorus from wastewater treatment discharges, leaking septic systems and stormwater runoff carrying nitrogen fertilizer, among other sources. These nutrients, in turn, feed algae super outbreaks, which block light from getting to the seagrass, causing it to die."

In 2017, manatees were upgraded from an "endangered" designation to "threatened" under the Endangered Species Act, with the U.S. Fish and Wildlife Service pointing to an increase in the manatee population and habitat improvements because of conservation efforts by Florida, Puerto Rico, Caribbean nations and public and private organizations.

The number of deaths this year is estimated to be about one-sixth of the population of manatees in the waters of the southeastern United States and Puerto Rico.

Members of the Florida Fish and Wildlife Conservation Commission pointed during a meeting last week to a need for long-term solutions.

"While we're dealing with the manatee mortality event, which is a symptom, we've got to also focus on the cure of water-quality improvement, especially in the Indian River Lagoon," Fish and Wildlife Commission member Michael Sole, a former secretary of the Florida Department of Environmental Protection, said.

Jim Saunders reports for the News Service of Florida.

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