Antillean manatee release program in Brazil

Summary

The Antillean manatee (Trichechus manatus manatus), Critically Endangered in Brazil despite a global Vulnerable listing and reduced to only 500-1,000 scattered individuals from Amapá to Alagoas states, has genetically distinct, low-diversity populations fragmented by overhunting, habitat loss and slow reproduction. Since 1994, Brazil's Chico Mendes Institute for Biodiversity Conservation has run a translocation program using calves rescued after stranding, a leading threat linked to coastal habitat degradation, rehabilitating them at a facility on Itamaracá Island through a staged diet before transfer at age one to a re-introduction oceanarium for a more natural diet. Selected individuals were released at three sites over 20 years, an initial site abandoned after two releases due to proximity to the state capital Maceió, then Porto de Pedras from 1998, chosen to bridge two disjunct populations, and an estuarine site in Paraíba, with staging-area acclimatization time increasing from 15 days early on to 3-12 months later. Post-release monitoring combined VHF, satellite and GPS radio tags with PIT tagging from 2004, using Florida's Manatee Rescue, Rehabilitation and Release Program criteria, a manatee surviving at least one year unaided counts as success; seven released manatees were tracked for an average of 2,700 days to assess breeding via pregnancy diagnosis and observed embracing behavior, though male-male coupling complicates that measure. Major obstacles included high long-term costs, the logistics of captive husbandry, and a scarcity of pristine coastal habitat in northeast Brazil. The project rates itself successful, crediting sustained investment from government, NGOs and private sources, two decades of refined release protocols, and strong local community engagement.