Tourists can be forgiven if they have been unable to view those 1,000-pound-plus mammals that make up the nation’s largest resident wildlife. They are manatees, and even scientists have to call upon modern electronics, including side-scanning radar, to count them.
The giant creatures, sometimes called sea cows, live in the Río Sixaola, the border between Costa Rica and northern Panamá.
There is a major effort afoot to protect the animals with sponsorship by the Interamerican Development Bank and the U.N. Global Environment Facility. The Smithsonian Tropical Research Institute is working with the Universidad de Costa Rica to first count the animals who live in the murky river water. The Smithsonian outlined the project in a recent news release.
Héctor Guzmán of the research institute is supervising the count aboard a modified U.S. Blue Bird school but that has been converted into a boat, the institute reported. The electronic gear is installed on the vessel, including hydrophone arrays.
Scientists estimated that from 100 to 150 manatees live in the river. In the past they were hunted for food, said the institute:
“Héctor’s team counts manatees with acoustics, both, passive (hearing them) and active (using a dual frequency sonar), and telemetry of tagged individuals. ‘This is a huge challenge for us,’ says Héctor, who has tracked humpback whales in the
Pacific and monitors corals around Panamá. ‘This is the first time in my life I’m working underwater with something I don’t see.”
While large areas of the Sixaola watershed are protected, deforestation, tourism, hunting and agrochemicals threaten the area, said the Panamá-based institute.
The research team will not only zero in on a more precise population estimate but also reveal their areas of preference for feeding and mating, as well as make conservation recommendations, said the research institute.