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B. Morales-Vela

Publications and source records attributed to B. Morales-Vela.

2 recordsLinked to original sources

Movement patterns of Antillean manatees in Chetumal Bay (Mexico) and coastal Belize: A challenge for regional conservation

Information from 15 satellite-tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high-use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos-monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation-area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long-distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long-distance movements and facilitate genetic exchange.

Chetumal Bay

Distribution and habitat use by manatees (Trichechus manatus manatus) in Belize and Chetumal Bay, Mexico

The nearshore coastal areas of Belize and of Chetumal Bay, Mexico, support one of the largest populations of manatees ( Trichechus manatus manatus ) in the Caribbean. In order to further document the distribution, relative abundance, habitat associations, and status of this population, we conducted three aerial surveys. The flights were done in January 1994, May 1994, and January 1995. Total manatee counts for each survey were 266, 207, and 171, respectively. Calves represented 7.4% of the grand total. Solitary manatees represented 62.8% of the total count. Manatees were numerous around the cays east of Belize City, in Placentia and Indian Hill lagoons, and in Chetumal Bay. Most manatees were observed in lagoons and rivers. Growing tourist activities should be assessed to avoid undesirable effects on manatees. Poaching and marketing of manatee products continues to jeopardize the animals in some areas. Current research and management activities are part of a cooperative international program to conserve the manatee in the Caribbean region.

Chetumal Bay