Date of Award


Document Type

Open Access Dissertation

Degree Name

Doctor of Philosophy (PhD)


Biology/Environmental Biology

First Advisor

Solange Brault

Second Advisor

John P. Ebersole

Third Advisor

Ellen M. Hines


The Drowned Cayes area of Belize, Central America is regionally important for the conservation of Antillean manatees in the Caribbean (Lefebvre et al. 2001; Quintana-Rizzo & Reynolds 2008). These islands are increasingly threatened by human activities such as tourism, development and population growth. The objective of this dissertation is to evaluate manatee habitat use and status in this area. The 5 specific objectives are to examine manatee (1) distribution in the Drowned Cayes, (2) use of seagrass beds and forage selection, (3) resting habitat use and selection (4) response to disturbance, and (5) trends in abundance and to suggest a method for monitoring manatees and other sirenians. The principal findings are that manatees utilize all habitat types within the area to meet a variety of their physiological and behavioral requirements. Some habitat types like seagrass beds and resting holes are clearly important components to the overall seascape. Manatees selectively forage on Halodule wrightii. Resting holes and seagrass beds that are adjacent to each other are a particularly important habitat configuration. Manatee habitat use seems to be resilient to mangrove removal, but foraging resources may not. Number of manatees sighted per scan over the duration of this study does not appear to have changed, but our method would not be able to detect a slight decline in abundance. Our survey protocol - point-based scan sampling from a small boat platform - is a relatively inexpensive, effective and repeatable method for monitoring sirenian population trends. By identifying important habitat types, foraging resources and resting areas, this research provides information that wildlife managers can use to promote watercraft guidelines and guide development decisions.