Abstract: A fragment of manatee habitat that crosses the border of Belize and Mexico includes both activity centres and travel routes linking rivers, lagoons, seagrass beds and mangrove islands near Chetumal Bay. Little is known about how geophysical features like coral reefs may influence manatee movements within and between habitat fragments like this. In this inductive study (1995-2001), we documented the seasonal occurrence of Antillean manatees at breaks in the northern Belize Barrier Reef. Survey locations were at: (1) Bacalar Chico National Park and Marine Reserve on Ambergris Caye (Basil Jones Cut) and (2) breaks in the reef 70 km south near the Drowned Cayes (Gallows Reef). The probability of sighting at least one manatee on a 20-min point scan survey was 40% (n=382). Sighting probability was significantly higher during the summer season (May-August) compared to winter months (December-March). Group size ranged from one to five manatees, peaking earlier (May) at the northern than southern site (August). Seventeen identifiable individuals accounted for 87% of the sightings at Basil Jones Cut, with re-sightings within and between years. One individual from Basil Jones Cut was re-sighted at Gallows Reef. Of the manatees for which sex was determined, 100% were males. No calves were sighted. To better understand manatee activity centres and travel routes, we identified potential hypotheses relating seasonal influences, stopover sites for travelling males, and habitat connectivity. To protect this highly vulnerable species, we recommend inclusion of the Belize Barrier Reef as an important component of manatee habitat within the coastal zone of Belize.

Pages: 342-354