Reproductive Behavior in a Captive-Released Manatee (Trichechus manatus manatus) along the Northeastern Coast of Brazil and the Life History of Her First Calf Born in the Wild

Abstract: The West Indian manatee (Trichechus manatus) is an exclusively herbivorous aquatic mammal. Recently, the stranding of live-orphaned calves has been the main threat to the species in northeastern Brazil. Since 1989, the Brazilian Manatee Project (PPB) has recovered 52 calf carcasses, of which 44 were alive. In 1994, “Lua” and “Astro” were the first manatees released from captivity in Brazil, and they have been tracked using radio telemetry methods. During daily tracking bouts, Lua’s behavior and movement patterns were recorded, including reproductive behavior. On 17 December 2003, while she was in the Maracaípe Estuary, Lua gave birth to her first calf. Beginning on 18 December 2003, the mother/calf pair began repeated, tidally determined moves from the estuary used during high tides to the sandstone reefs used during low tides. Four days after the birth, an increase in motorized boat traffic in Maracaípe Estuary was observed. On 22 December, Lua and her calf moved to Serrambi Beach and remained outside the estuary in the reef area. On 25 December, the ninth day after the birth, Lua was sighted alone. On 26 December, the calf was found dead at Serrambi Beach. The place of birth supports the hypothesis that estuaries are birthing areas for manatees. The fact that Lua established her main fidelity site and gave birth in an area where manatees had previously been extirpated indicates a potential for reestablishing the species in its historical range via the rescue, rehabilitation, and reintroduction program developed by PPB. The calf’s death confirms the fragility of the species’ conservation. The last 44 live-orphaned calves seem to have been caused by habitat destruction and/or human disturbances within their habitat. The lack of effective coastal management programs, despite being mandated within the federal Environmental Protection Areas established in the region, are factors that severely impair conservation of the Antillean manatee in Brazil.


Document Type: Research article

DOI: 10.1578/AM.31.4.2005.420

Page Numbers: 420 – 426

$12.00Add to cart