Marine Canary in the Coal Mine: The Latest Threats to Manatee Survival and Efforts to Save Them

By Catherine Awasthi and Ralph A. DeMeo

Florida Bar Journal, Vol. 95, No. 4   July/August 2021   Pg 52

Your authors grew up in Florida enjoying the natural wonders of a relatively unspoiled state. One of these natural pleasures, perhaps the most unique, was experiencing the magnificent manatee in Florida waters. Sometimes referred to as “sea cows” because of their roly-poly appearance, vegetarian diet, slow motion, and gentle ways, manatees have become, like their far more aggressive carnivorous cousins the alligator, a symbol for the state of Florida. One of the most successful motor vehicle specialty plates offered by the state features the manatee. They are undoubtedly beloved marine mammals deeply important to the people of Florida. One could even say they are Florida’s “charismatic megafauna.” Yet, like so many other gentle creatures, the manatee’s primary survival threat comes from human activities. This man-made threat, which takes many forms, has resulted in a major change in manatee survival and sustainability.

In the first three months of 2021, an unusual catastrophic manatee mortality event shocked Floridians, including usually stoic government officials and scientists. While manatee deaths every year are not unusual, as a result of a number of factors to be discussed in this article, there was an unprecedented discovery of hundreds of manatees found dead and dying in Florida waters. As scientists scrambled for answers, the federal government stepped in to assist — a sign that these mass manatee mortalities could be linked to a larger environmental issue. Perhaps even more alarming, the National Oceanic and Atmospheric Administration Fisheries officials report that unusual mortality events could indicate deeper issues with implications for human health.^[1] This extraordinary and tragic incident of the death of hundreds of manatees — like the canary in the coal mine, could be a harbinger of a larger ecological disaster underway in the Sunshine State.

The legal landscape in place to protect this iconic creature has been inconsistent and has faced much criticism. Regulators have moved West Indian manatees up and down the ranks of the Endangered Species Act’s levels of protection in the past decade. At the same time, Florida has experienced several water-quality disasters, including most infamously red tide and toxic algae blooms. Although there has yet to be a specific cause linked to the surge in manatee deaths thus far in 2021, there is no question that manatees, as marine mammals, are impacted significantly from the degraded Florida waters plaguing their habitats.

This article explores the history and current status of legal protections for Florida’s manatees. It also lays out the current state of the 2021 unusual mortality event under the Marine Mammal Protection Act. As marine mammals, they are particularly susceptible to changing environmental conditions, this article also briefly touches on the recent large-scale water quality degradation events and reviews the regulations in place to help restore and protect water quality. This article also assesses the arguments, both scientific and governmental, on causes of the recent mass manatee mortalities.

Florida Manatees: Federal and State Protection

The Florida manatee is a subspecies of the West Indian manatee.^[2] The species generally spans Florida and southeastern Georgia, and the mammals are found in freshwater, brackish, and saltwater habitats.^[3] Florida manatees, as vegetarians, depend on aquatic vegetation, such as seagrass and turtle grass for food.^[4] They also require fresh water for drinking.^[5] The creatures have few natural predators, and the U.S. Fish and Wildlife Service (FWS) states that their greatest natural threats are “exposure to cold temperatures, hurricanes, and poisoning from red tide.”^[6] Healthy manatees can live for several decades.^[7]

Until recently, the West Indian manatee was listed as endangered under the Endangered Species Act (ESA). In 2017, regulators moved their status from “endangered” to “threatened.”^[8] The down-listing means that the manatee is no longer considered in danger of extinction throughout all or a significant portion of its range but is likely to become so in the foreseeable future without continued ESA protections.^[9] Nonetheless, as a threatened species, manatees will continue to have protections under the Marine Mammal Protection Act (MMPA).^[10]

Laws to safeguard manatees date back to the British occupation of East Florida in the 18th century, making them some of the oldest wildlife protection laws in North America.^[11] Then, the Florida manatee was among the first animals to gain protection under the precursor to the ESA, the Endangered Species Preservation Act of 1966.^[12] The FWS listed the West Indian manatee as endangered as well in 1970.^[13] A decade later, critical habitat protection was designated for the Florida manatee under the ESA.^[14] This designation delineated specific waterways in Florida that were known to be important concentration areas for manatees at that time.^[15] In 2008, some conservation groups petitioned to expand that 30-year-old designation due to changing human populations and manatee habitats.^[16] Unfortunately, FWS issued a notice of 12-month petition finding in 2010 that indicated revisions to critical habitat for the Florida manatee are warranted, but that the agency lacked the funds to act on the findings.^[17] Therefore, the critical habitat remains the same in 2021.

As stated previously, West Indian manatees remain protected under the MMPA because the species is categorized as “threatened” under the ESA.^[18] This classification indicates the stock of the species is “depleted,” making manatees eligible for additional protection measures under the MMPA.^[19] The MMPA makes it illegal to “harass, hunt, capture or kill any marine mammal.” ^[20] The manatee is also protected by the Florida Manatee Sanctuary Act of 1978, which states: “It is unlawful for any person, at any time, intentionally or negligently, to annoy, molest, harass, or disturb any manatee.”^[21] Further protections include state-mandated Manatee Protection Plans (MPP) implemented in 13 “key” counties identified by the Florida Fish and Wildlife Conservation Commission (FWC).^[22] These FWC-approved plans regulate reviews of permit applications for new or expanding boat facilities.^[23] Even more restrictive are FWC-designated manatee sanctuaries and manatee refuges. The sanctuaries are areas where “all waterborne activities are prohibited,” while the refuges “are areas where certain waterborne activities are restricted or prohibited.”^[24]

Catastrophic Mortality Event: Manatee Graveyards

Despite the multitude of protections in place, manatees are dying at an alarming rate in 2021. FWC has documented 696 manatee deaths as of April 23 — nearly 460 more than the five-year average for the same period.^[25] Also, as of the April manatee mortality report, 463 dead manatees have yet to be necropsied;^[26] 34 deaths were due to watercraft injuries, 25 to cold stress, 97 to natural causes, and 17 deaths were undetermined.^[27] In 2020, the COVID-19 pandemic put a halt to manatee death necropsies for two months, and as a result, causes of death were never determined for roughly one-third of the nearly 600 known fatalities.^[28]

In a frantic response to the mass mortalities, the FWS declared an Unusual Mortality Event (UME) under the MMPA. A UME is “a stranding that is unexpected; involves a significant die-off of any marine mammal population; and demands immediate response.”^[29] This designation allows National Oceanic and Atmospheric Administration Fisheries officials to assist in the investigation and provides more resources for conservation. In 2013, Florida lost 830 manatees, and a UME was declared for the Florida Manatee.^[30] The Indian River Lagoon (IRL) was the site of an unknown manatee mortality episode following a prolonged non-toxin-producing brown tide algal bloom.^[31] Researchers looked into the impact of algal blooms on manatees, as 277 deaths were associated with a red tide in Southwest Florida.^[32] Scientists discovered the highest concentrations of the toxin associated with red tide in the necropsied manatee stomachs.^[33] Overall, scientists pointed to both massive depletion of seagrass (a manatee food staple) due to brown tide algal mats blocking growth, and manatees then turning to an alternate food source (red drift algae), as causes of death in the 2013 mortality episode.^[34]

Focusing back on the 2021 manatee mortality episode, the majority of deaths were reported in the same area as in 2013: the IRL.^[35] One Florida news agency spoke with a resident who witnessed manatee bones littering the shoreline in Merritt Island: a manatee graveyard.^[36] Although a majority of the 2021 manatee carcasses have yet to be necropsied, scientists and Florida officials have theories. A veterinarian at the FWC marine pathology lab reported that half of the necropsied dead manatees are adults with empty guts, atrophied livers, and depleted fat and muscle — all pointing to starvation, something the veterinarian has never been seen before.^[37] The same veterinarian noted that “seagrass began plummeting around 2011,” after a widespread “superbloom” of algae smothering seagrass in the IRL.^[38] Manatees appear to be losing a vital food source in the wake of red tide outbreaks and toxic algae blooms.

FWC created a website dedicated to investigating and reporting on the 2021 UME. Officials stated environmental conditions in portions of the IRL are concerning.^[39] They report that preliminary information “indicates that a reduction in food availability is a contributing factor.”^[40] Manatees depend on sea grass as a food source in warm-water areas, especially during winter. FWC noted that persistent algal blooms have led to a dramatic reduction in seagrass in the IRL.^[41] The agency very clearly stated that, despite the ongoing investigation, the high mortality is “likely due to a decline in food availability.”^[42]

Sources of Pollution and Other Threats Examined

• Agricultural Runoff — Algal bloom formation in Florida waters has been linked to the agricultural industry. Nutrient pollution from agricultural operations (non-point-source pollution) is regulated within the state-developed Total Maximum Daily Loads (TMDLs) program.^[43] A TMDL is “a scientific determination of the maximum amount of a given pollutant that a surface water can absorb and still meet the water quality standards.”^[44] In order to meet goals established by TMDLs, Florida employs planning tools known as Basin Management Action Plans (BMAPs).^[45] BMAPs must attempt to implement and maintain TMDLs by integrating “the appropriate management strategies available to the state through existing water quality protection programs.”^[46] When the Florida Department of Environmental Protection (FDEP) adopts a BMAP that includes agriculture, producers must either implement state-adopted best management practices (BMPs) or conduct monitoring to show they are not violating water-quality standards.^[47]

The Florida Department of Agriculture and Consumer Services (FDACS) determines what BMPs are appropriate for various types of operations, and details such in their BMP manual.^[48] If non-point-source dischargers included in a BMAP implement all required BMPs, their discharge will be presumed to be in compliance with state water-quality standards.^[49] This means when a non-point-source discharger implements required BMPs, FDEP “is not authorized to institute proceedings against the owner of the source of pollution to recover costs or damages associated with the contamination of surface water or groundwater caused by those pollutants.”^[50] Meanwhile, almost 2.5 million pounds of nitrogen and phosphorus from agricultural chemicals, lawn fertilizers, and leaky septic tanks flow into the IRL each year.^[51] Those numbers come from FDEP in a 2020 proposal to revise the BMAP for the IRL.

FDEP works with Florida’s water management districts in an adaptive management approach to monitoring nutrient loads in BMAPs like the IRL.^[52] For instance, FDEP conducts seagrass evaluations every two years to determine if agricultural producers within a BMAP are complying with nutrient loading allocations.^[53] To meet seagrass regrowth requirements, “required reductions are included in the TMDL rule language to get to the necessary water quality conditions for restoring historic seagrass depth limits within each BMAP.”^[54] When the seagrass reports are released indicating seagrass has not met the requisite growth, FDEP will then re-assess the nutrient loading allocations. Based on the notion that seagrass is the “primary keystone species” indicating the health of the IRL, FDEP proposed new nitrogen and phosphorus allowances for the IRL BMAP in 2020.^[55] IRL agricultural communities were asked to meet the suggested allocation goals by the year 2030.^[56]

In terms of oversight for those producers required to enroll and implement BMPs for nutrient loading under F.S. §403.067 (2020), the process has been controversial. A landowner or producer who simply submitted an official “notice of intent to implement BMPs” form enjoyed a presumption of compliance with state water-quality standards.^[57] FDACS is required to verify that producers are implementing applicable BMPs.^[58] The agency has historically verified BMPs in one of two ways: implementation verification site visits and producer self-surveys.^[59] However, Senate Bill 712 (the Clean Waterways Act) passed in 2020, requires FDACS to both complete implementation site visits every two years in lieu of self-reporting surveys, as well as complete an enrollment site visit with producers.^[60] The Clean Waterways Act also required that agricultural producers in the BMP program now submit their nutrient management records to assist FDACS in achieving the program’s objectives.^[61] This provides extra oversight for verifying that nutrient load reductions are met.

A large setback to the BMP program is the lack of staff available to enroll producers and to then verify BMP implementation on site. Unfortunately, in 2020, the COVID-19 pandemic further limited in-person site visits. Therefore, verifying BMP implementation was even more of a challenge.^[62] Conversely, FDACS was allocated funding in the 2020-21 budget to hire eight additional positions.^[63] Therefore, when staff are safe to return to the field following the pandemic, they will likely be more equipped to verify BMP implementation.

Another large setback with the BMP program is the lack of an enforcement timeline for producers not properly implementing applicable BMPs. Currently, 5M-1.009, F.A.C. requires a “corrective phase,” which is FDACS first touch in addressing producers who are not properly implementing applicable BMPs.^[64] If a producer remains non-compliant in implementing applicable BMPs, FDACS will make a second “touch” listed as the “remedial” phase in 5M-1.009, F.A.C.^[65] Finally, if the producer remains non-compliant, FDACS is required to notify FDEP “within 60 days after the date of scheduled completion of remedial measures…of any [e]nrolled [p]roducer or [l]andowner that refuses or fails to implement applicable BMPs.”^[66] FDEP has the authority to take any compliance enforcement actions.^[67] Missing from the statutory enforcement language is any indication of what consequences would look like for non-compliant producers and when they would be enforced.^[68]

In January 2019, Florida Gov. Ron DeSantis issued Executive Order 19-12 (Item C), requiring FDACS to expedite BMP enrollment processes for certain BMAPs.^[69] The IRL BMAP was not included in that order. However, Gov. DeSantis did approve $25 million in funding for IRL water-quality improvement projects.^[70] Additionally, FDEP expanded protections in three individually updated BMAPs for the IRL in February 2021.^[71] FDEP stated in part that an increased understanding of the detrimental effects of harmful algal blooms on seagrass, wildlife, and human health prompted a call for decreasing nutrient loads to the IRL.^[72]

• Septic Tanks and Untreated Wastewater — Leaky septic tanks and untreated human wastewater are other major sources of nutrient pollution into Florida’s waterways. In December 2020, 126 million gallons of sewage spilled onto the streets of Broward County neighborhoods after six sewer main breaks.^[73] Much of that plagued canals and rivers and led to a decline in seagrass. As of the April 2021 manatee mortality report, 53 manatees had died in Broward County — more than any other county;^[74] 38 of those have yet to be necropsied.^[75] In sum, there is a correlation between leaky septic tanks and sewage spills to manatee mortalities. Gov. DeSantis’ 2019 Executive Order 19-12 (Item H) did direct FDEP to “establish a septic conversion and remediation grant program” to help local governments begin sewage improvements.^[76]

• Watercraft — Overall, most causes of manatee mortality are directly related to human contact or encroachment. Traditionally, watercraft strikes have accounted for 25 to 30% of deaths statewide.^[77] FWC data indicated boaters set a new record in 2019, with 137 total manatee deaths resulting from watercraft strikes — 13 more than in 2018.^[78] This year is no different: 34 watercraft-related mortalities determined from January to April 23, 2021 — eight more than in the same time period in 2020.^[79] Although manatee protection zones have been implemented since 1979, FWC data indicated mortality from boat collisions are on the rise.^[80] Possible reasons include regulations are either not being enforced or that further slow-speed restrictions are necessary, as manatees need time to respond to approaching watercrafts.^[81]

The most prevalent difference during this UME remains the more than 400 manatees not necropsied, and the unusually high number determined to have died from “natural” causes.^[82] Natural causes include deaths resulting from “infectious or non-infectious disease, birthing complication, natural accident, or other natural causes such as red tide toxicity.”^[83]

Looking Ahead: ESA vs. BMPs

As of the most recent aerial surveys in January to February 2019, there are at least 5,733 manatees in Florida.^[84] With the 2021 mass mortality thus far, there are closer to 5,000. Due to the COVID-19 pandemic, FWC does not plan to conduct the manatee survey this year — so Floridians will have to wait to see the final impact of this mass mortality event. As previously stated, FWC has identified lack of food as a potential cause of 2021 manatee deaths. However, the underlying issue has yet to be identified. Yet, the focus on the 2017 ESA manatee delisting as a major concern is misguided. The focus should be on generating the proper resources to ensure manatee protection on a state level.

The efforts of another organization bear mention here. Save the Manatee Club (SMC) is a nonprofit with the mission to protect manatees and their habitat. When the beginning of the year brought an alarming number of manatee deaths, the SMC executive director highlighted some key concerns. First, staffing for the federally managed manatee program with FWS has been reduced; there is no active Manatee Recovery Team, Manatee Implementation Team, or Manatee Warm-Water Task Force.^[85] SMC proposed that FWS “must intensify its support for the efforts of the Manatee Rescue and Rehabilitation Partnership with emergency funding to ensure that every sick and injured manatee will receive emergency assistance and care at partner facilities.”^[86] Second, new sources of nutrient pollution must be prevented from entering the IRL before it can be functionally restored.^[87] Ideally, “seagrasses will begin to reestablish on their own,” but only if we “reverse those conditions that lead to the loss of seagrasses in the first place….”^[88]

Meanwhile, manatees essentially receive the same federal habitat protection as “threatened” as they did when listed as “endangered.” However, when sifting through the comments and responses within the 2017 delisting final rule, some concerns about seagrass loss and habitat degradation stood out. First, one commenter and the Miccosukee Tribe expressed concerns over the proposed rule not taking into account extensive seagrass die-offs in Brevard County.^[89] The FWS responded that events leading to loss of seagrass are “broadly considered in model projections which suggest that the population can withstand such events.”^[90] Additionally, one public commenter was concerned that the proposed delisting rule did not take into account “the cold weather, Indian River Lagoon, and red tide die-off events that occurred between 2010 and 2013.”^[91] The FWS responded that the Manatee Core Biological Model, which evaluates the effect of various threats on the Florida manatee population, did not evaluate these events because 2010 to 2013 adult survival rate estimates needed for the model runs were not available when this rule was written.

Overall, the final rule indicated that manatee habitat degradation and loss remain a threat, and ongoing efforts to address these threats remain a recovery priority.^[92] This suggests that the primary focus should not be on the ESA status of the West Indian manatee, but instead on stronger regulations for nutrient and wastewater pollution. The IRL has lost 45% of the seagrass meadows since the summer of 2010, which amounts to 32,000 acres of lost seagrass.^[93] Communities along the IRL are beginning to notice the correlation between these pollutants and the loss of iconic manatees. Old septic tanks are being replaced or repaired along some portions of the lagoon, while other projects are being implemented to reduce the phosphorus content of some wastewater plants.^[94] Additionally, in 2016, Brevard County residents voted in favor of a tax increase to fund a $300 million, 10-year clean-up project for the IRL.^[95]

Reducing the nutrients and pollutants added to water can minimize instances of toxic algae blooms or even completely eliminate their formation.^[96] FDACS is currently working toward this goal. In January, the agency issued a notice of proposed rulemaking, revising the implementation verification process and adopting a nutrient application record form by law.^[97] Language has been added to the BMP regulations, such as placing a 60-day limit for required producers to undertake a mandatory enrollment site visit.^[98] Even more critical, the proposal includes the two-year implementation site visits to ensure compliance and a set timeframe for those who fail to meet requirements: “In no case shall the overall timeframe for completion of corrective and remedial measures extend beyond the date of the next implementation verification site visit.”^[99] These timeframes are essential for this nutrient pollution regulation program to abide by the ultimate goal of the CWA: ensuring clean water for all.

The Florida House of Representatives also expressed alarm by the mass manatee mortalities. The House’s supplemental funding list published April 26 indicated $8 million assigned to FWC for “Manatees Habitat Restoration.”^[100] Known as a “sprinkle list,” the funding was not marked as recurring, which means it is not guaranteed for the future.^[101] The list explained the funding is provided “to restore manatee access to springs and provide habitat restoration in manatee concentrated areas.”^[102] This is a critical effort needed to protect dying manatees.

Conclusion

Florida is facing an ecological emergency due to the 2021 mass manatee mortalities. Scientists and Florida wildlife officials both express concern over seagrass shortages, due to nutrient pollution. Therefore, whether listed as “endangered” or “threatened” under the ESA, manatees will continue to face starvation until action is taken at the state and local levels to reduce nutrient loading in Florida’s waterways. To preserve these sacred sea cows, more needs to be done to address the underlying threats to their populations, starting with more focused study and action to prevent the large-scale die-off due to starvation and other man-made environmental conditions. These conditions threaten not only manatees, but all marine and even human life if left unchecked. In short, for the sake of all life, we must save the manatees.

This column is submitted on behalf of the Animal Law Section, Steven B. Spain, chair; Ralph A. DeMeo, editor; and Gregg R. Morton, guest editor.