Editorial: Endangered species
Published: Tuesday, September 2, 2014 at 6:01 a.m.
Last Modified: Monday, September 1, 2014 at 12:32 a.m.
Manatees can be seen swimming near the shores of coastal Florida, but they are not doing swimmingly as a species.
The 830 manatees that died in 2013 set a new mortality record. It is more than double the average annual mortality and eclipsed the second-highest record of 766 manatee deaths in 2010.
Despite this, the U.S. Fish and Wildlife Service is considering whether to downlist manatees from being classified as “endangered” to the lesser classification of “threatened.”
Although manatees have benefited from protections associated with its status under the Endangered Species Act, the potential danger of extinction should weigh heavily on the Fish and Wildlife Service.
The agency's staff has, in the past, recommended the change; their expertise should be given due consideration.
However, another expert — James Powell, a biologist with a doctorate and other advanced degrees — makes a compelling case against the change.
Powell has studied manatees in Florida and throughout the world. He formerly administered the Florida Fish and Wildlife Conservation Commission's research program on manatees; today he is executive director of Sea to Shore Alliance, a nonprofit organization he founded.
The Fish and Wildlife Service will weigh five factors in its decision: threat to habitat; overutilization of habitat; disease or predation; inadequacy of regulatory mechanisms; and other natural or man-made factors.
Here are Powell's thoughts on the factors:
Habitat threats: Threats include reduction of warm-water sanctuaries, water quality, water pollution and loss of food sources such as sea-grass beds. With increasing human populations, the threats are expected to increase and intensify.
Boat strikes: With increasing human and boat populations in Florida, boat collisions with manatees will likely rise as boating activity increases following the recession. Over the past six years manatee deaths caused by boat collisions averaged about 84 a year, despite widespread regulatory zones.
Cold-related illness and death: Despite natural warm springs and power plant discharges, manatees can still experience high levels of mortality during a cold winter. In 2010 marine biologists recorded 282-plus manatee deaths from exposure to cold — a record high. This is likely to increase as power plant operations are modified over the next few decades and sources of natural warm water diminish due to changes in climate and extraction of water from the Floridan Aquifer.
Overall population: While the science argues against looking at population figures as a significant factor, the 2014 minimum population estimate (4,824) is not many, considering we had more than 800 manatee carcasses last year. These numbers are worrisome since most of these deaths are due to factors that we cannot control, such as cold weather and red tide.
Despite the slow and very slight increase in the number of manatees during the past 50 years, threats to survival have increased. Since 2007, Florida manatee mortality has increased more than 50 percent.
The mortality numbers are a clear indication that threats to the species have not been lessened, and in fact have increased and broadened.
Clearly, the science that analyzes the existing and emerging threats indicates a “no” to a move to threatened status at this time.