Aerial Survey Spots Record Number of Manatees

Counting Manatees
Photograph courtesy Tony Rath via Oceanic Society
A manatee rests among the mangroves in coastal Belize, one of a record-high 507 individuals spotted during aerial surveys in the Central American nation that serves as the primary home of the endangered Antillean manatee.
Slow moving and air breathing, manatees have lifestyles conducive to such aerial surveys, but, encouragingly, the recent count still represents a minimum because many animals no doubt went unseen. Scientists also reported that ten percent of the manatees recently spotted from the air were calves.
(See video of mating manatees.)
Such science shows not only how many manatees there are but how they use the landscape, according to Birgit Winning, president of the Oceanic Society.
"These aerial surveys show areas of concentration where manatees are found in numbers," she said. "These areas are important to them for things like feeding or nursing and they need special protections from threats, including habitat degradation or boat collisions due to high traffic."
—Brian Handwerk
Published August 22, 2012
Spotters
Photograph courtesy Tony Rath via Oceanic Society
Scientists peer from a Cessna 206 aircraft while searching for manatees above Belize. A recent survey at Turneffe Atoll was led by the Oceanic Society, which runs a manatee research project there, and by LightHawk—a network of 200 pilots who volunteer to aid conservation work across North and Central America.
Belize's Coastal Zone Management Authority (CZMAI) also recently scanned the mainland coast for manatees using aerial surveys—a time-tested procedure that's been part of management efforts here since 1977.
"Expecting around 300 animals, we are very excited over the results of this year's national manatee survey, with a record 507 manatees observed. The previous highest count was less than 350," said Nicole Auil Gomez, a scientist with Belize's CZMAI.
Published August 22, 2012
“Sea Cows”
Photograph courtesy Tony Rath via Oceanic Society
An Antillean manatee swims in Belize's clear, coastal waters.
These "sea cows" are grazers who each day eat a tenth of their own enormous weight (up to 1,300 pounds or 600 kilograms) in aquatic grasses, weeds, or algae. Though they are born underwater and spend their entire life swimming, these marine mammals must breathe air at the surface.
This biological requirement, and their tendency to move slowly, has made them vulnerable to harm from poachers and passing motorboats.
But Belize has established three manatee protected areas and a stranding network and rehabilitation facility. The nation also supports manatee research.
"We are learning more about their movements, including that they do travel between Belize and Mexico, and (their) genetic makeup," said Gomez. "I will be using this new information, including these aerial survey results, to produce a revised Manatee Recovery Plan for the conservation of the species in Belize."
(See pictures of freshwater mammals.)
Published August 22, 2012
Antillean Manatees
Photograph by Luciano Candisani, Minden Pictures/Corbis
An Antillean manatee (Trichechus manatus manatus) swims in coastal waters off Brazil. The endangered animal is one of two species of West Indian Manatee, the other being its close relative, the Florida manatee.
Antillean or "Caribbean" manatees number only about 2,500 adults, and their declining population is listed as endangered by the IUCN Red List of Threatened Species.
(Related: "Manatees Have 'Long-Distance' Sense of Touch, Experts Say.")
"The majority of us Belizeans strongly identify with the coastal zone and its resources, whether it is for residences, food, transport, tourism, jobs, and of course fun," said Gomez. "Manatees are certainly one of the most charismatic animals we take pride in and definitely want to see in our waters for decades to come."
Published August 22, 2012
Turneffe Atoll
Photograph courtesy Tony Rath via Oceanic Society
Turneffe Atoll, some 25 miles (40 kilometers) off the coast of Belize (see map), is the largest and most biologically rich coral atoll in the Western Hemisphere. It's also a manatee hotspot and the only offshore site known to be frequented by the endangered Antillean manatee subspecies.
The atoll boasts large intact areas of mangroves and seagrass that manatees love, but its popularity with these marine mammals is also a bit of a mystery. The site has no known freshwater source and manatees typically frequent freshwater locales like coastal springs.
(See how boat alarms could save manatees.)
Published August 22, 2012
Manatee Family
Photograph courtesy Tony Rath via Oceanic Society
A group of manatees spotted in an aerial survey over Belize includes a mother and calf. The endangered population has been relatively stable here in recent years, according to the Oceanic Society's Winning.
"There is still some poaching, because historically people from other countries have come and killed manatees to sell on the market," she said. "But there are also some additional patrols that with funding will be implemented for more protection. Belize should be applauded for doing as good a job as they have in protecting these marine mammals."
(Related: "Dolphins and Whales Hunted Despite Protections.")
Published August 22, 2012
Next: Giant Megafishes >>
Photograph by Zeb Hogan, AP
Published August 22, 2012