West Indian Manatee Conservation
Threats to Their Survival and Efforts to Conserve the Species
May 13, 2009
If precautions are not taken to conserve these magnificent animals, they may follow the Stellar's Sea Cow into extinction. Current threats the West Indian manatees face, coupled with their low reproductive rates, make the species particularly vulnerable.
Threats to Manatees - Habitat Loss
The human population is growing exponentially, and development along Florida's coastlines destroys valuable manatee habitat. Many waterways are altered by dredging and filling, and construction activities often destroy the seagrass beds manatees rely upon for food sources. Boat propellers also cut paths through the seagrass beds, leading to "seagrass scarring". Over thirty percent of seagrasses have been lost since the 1940s.
Threats to Manatees - Anthropogenic Factors
The single greatest cause of documented manatee mortality is collision with watercraft. They may be struck by the hull of a boat, crushed between the boat hull and shallow water bottom, or sliced by the propellers. A 2000 National Geographic article stated that 900 manatees had been killed by boats since 1994 (not including the numerous injured individuals). Manatees cannot hear low-frequency sounds well, such as those emitted by boats, so they do not know that they are in danger in order to get out of the way. The Gersteins at Florida Atlantic University are developing a high-frequency warning device to be attached to boats to warn manatees of a boat's presence. Additionally, humans sometimes chase, poke, grab, ride, feed, and offer water to manatees, which has been known to force manatees to leave their warm water refuge, endangering their lives, and has separated mothers and calves. Human presence creates stress and harassment for this already imperiled species. Research reflects that a large percent of manatee deaths are the direct result of human activity.
Threats to Manatees - Pollution
Litter in waterways (plastic sacks, fishing line, etc.) may entangle or become ingested by manatees, posing a direct threat to their survival. Oil exploration/spills poison their aquatic habitat. Pesticides, fertilizers and detergents enter waterways, contaminating the water and the manatees' food sources, and cause eutrophication or "red tides". The excess nutrients feed microscopic dinoflagellates, causing their populations to explode, making the water appear red. They create toxins which may be ingested by manatees. In 1996, 151 manatee deaths were attributed to a red tide.
Manatee Protection
Manatees are a federally protected species under the Endangered Species Act of 1973 and the Marine Mammal Protection Act of 1972. Harming or harassing a manatee is punishable by one year in prison and $100,000. The US Fish and Wildlife Service coordinates the Manatee Recovery Plan, which establishes speed zones for boats, promotes manatee education, and purchases areas for manatee protection, among other things. The Save the Manatee Club, established in 1981, advocates legislation on behalf of manatees, and raises funds for equipment used in manatee rescue and rehabilitation efforts.
How to Help if You Live Near Manatees
- When boating, wear polarized sunglasses to be able to see beneath the water's surface, avoid shallow areas and seagrass beds, constantly watch for manatees to avoid hitting them, do not speed, avoid manatee sanctuaries, and keep your distance if you see a manatee.
- Do not litter - discard trash properly so it does not end up in waterways.
- Retrieve any monofilament line/fishing hooks you find and discard properly.
- Do not feed or water manatees.
- Look but do not touch!
- Request free "Watch for Manatees" signs from the Save the Manatee Club for your boat or dock to warn others to slow down.
How to Help No Matter Where You Live
- Write a letter to Florida's Governor and tell him you support strong manatee protection:
The Honorable Charlie Crist
The Capitol
Tallahassee, FL 32399-0001
P- 850-488-7146
F- 850-487-0801
email- charlie.crist@myflorida.com
- Write a letter to your U.S. senator/representative and tell him/her you support strong manatee protection (to find yours call 800-688-9889 or visit www.congress.org).
- Join Save the Manatee Club's email action network.
- Purchase manatee-related gifts from the Save the Manatee Club to show your support.
- Adopt a manatee from Save the Manatee Club for you or as a gift.
Source: "Manatees" by Save the Manatee Club
 |
 |
