Reintroduction of Manatees in Guadeloupe

Reintroduction of Manatees Trichechus manatus into Guadeloupe, Lesser Antilles: Issues, Questions and Possible Answers Prepared by: Drs. John Reynolds and Dana Wetzel Mote Marine Laboratory, Sarasota, Florida Prepared for: Parc National de la Guadeloupe Date: 6 May 2008 Financial support Fonds de Coopération Régionale Fonds Européen de Développement Régional PRÉFECTURE DE LA RÉGION GUADELOUPE 1 Background and Goal: The National Park and other entities in Guadeloupe are interested in re-establishing manatees in the waters of the natural reserve called “Grand Cul-de-Sac Marin.” The species has been extinct in the waters of Guadeloupe for a number of decades, having been wiped out locally by hunting; some elders apparently recall seeing manatee meat available for food. Manatees remain a part of local folk-lore and the history of Guadeloupe (e.g., the town of Lamentin, located near Grand Cul-de-Sac Marin); in fact, a former “manatee processing area” exists near Vieux Bourg (Grande Terre). This goal of re-introducing manatees has existed since a feasibility study was conducted in 2002. Basis of this report: Our report is based to a large degree on a site visit to Guadeloupe from 6-11 April 2008. The trip was funded by the National Park, but included visits with a number of individuals and groups. In addition, we base this report on our knowledge of marine science, marine mammalogy, ecology, health, and toxicology. Reynolds is Chairman of the U.S. Marine Mammal Commission, President of the international Society for Marine Mammalogy, Director of the Center for Marine Mammal and Sea Turtle Research at Mote Marine Laboratory, and past co-Chair of the IUCN Sirenian Specialist Group. Wetzel is an ecotoxicologist specializing in marine organic chemistry. She is Manager of the Aquatic Toxicology Program at Mote Marine Laboratory and has conducted research on health and contaminants of marine mammals and/or marine environments around the world. Issues to consider before proceeding: The goal of re-establishing a species that has been extirpated by human activities is a noble one. It is also extremely difficult to achieve. We believe that such a venture should not be undertaken unless there is reasonable assurance of success. Otherwise, animals selected for the re-introduction may simply be lost—a tragedy, especially when dealing with endangered species. The following represent some categories of topics or actions that should be considered prior to seriously undertaking this difficult and risky process: Category 1 : Legal status and transparency Marine mammals elicit very strong feelings among people. The taking of endangered manatees for any purpose, even a noble one, is likely to draw considerable attention and a very mixed response. It will be important for the government of Guadeloupe and the National Park to have done a very careful analysis to ensure that: a) the taking and relocation of manatees is done with transparency and in compliance with all relevant laws and conventions (e.g., CITES, SPAW Protocol); and b) a well- articulated justification exists that notes the conservation benefits and legality of the re-introduction process. Note that we are not lawyers or specialists in international policy; hence we cannot adequately advise the Guadeloupe government on this important point. However, the process is already under some scrutiny and drawing some concern among certain groups. For example, prior to our 6-11 April site visit, a delegation of officials from Guadeloupe visited officials in Cuba to discuss the feasibility of the re-introduction project using manatees from Cuba. From the perspective of officials with whom we met 2 in Guadeloupe, that visit went well and offered promise. However a colleague who is an expert in biology and conservation of manatees wrote Reynolds to state: “colleagues in Cuba….were very upset that the Cuban government…might be catching or selling manatees to Guadeloupe.” Our point is simply that the re-introduction of manatees will come under extremely close scrutiny and that all parties concerned need to be as transparent and communicative as possible. Category 2: Lessons to be learned from re-introductions of other species The First International Wildlife Reintroduction Conference was held in Chicago, Illinois (USA) on 15-16 April 2008. The website for the event is at: http://www.lpzoo.org/reintroworkshop/registration.html We left copies of the Conference program with scientists in Guadeloupe during our site visit. Based on the titles of the presentations being delivered at this conference, we expect that it would have been very useful to attend. Information acquired from this conference or others with a similar focus in future years could save money and time and help ensure success of a manatee reintroduction program . Therefore, we recommend that, if at all possible, someone representing the Parc National de la Guadeloupe or some other involved agency acquire copies of the abstracts of presentations from the April 2008 conference and make an effort to attend future conferences on this subject . Category 3: Systematics of manatees in the wider Caribbean. Two subspecies of the West Indian manatee ( Trichechus manatus ) occupy waters and coastal areas of the nations of the wider Caribbean. The Florida manatee ( T.m. latirostris ) numbers approximately 3,400 individuals and is found in the waters of Florida (USA), with occasional individuals wandering into Bahamian or Cuban waters. The Antillean manatee ( T.m. manatus ) occupies the remaining range of the species ( i.e., the waters of nearly two dozen countries) and may number around 5,500 individuals (Quintana-Rizzo and Reynolds 2007). We believe that the reintroduction should consider only individuals representing the Antillean manatee . Category 4 : How many manatees would be needed for a successful re-introduction effort? This is a difficult question to answer. In one sense, the more individuals one could introduce the better, from the standpoints of maintaining genetic diversity and avoiding problems associated with the inherent vulnerability of small populations to extinction. However, among the countries and islands of the wider Caribbean, only five (Belize, Brazil, Colombia, Mexico, and Nicaragua) have an estimated Antillean manatee population greater than 500 individuals (Quintana and Reynolds 2007). Removal of manatees from smaller populations could create undue and unacceptable risk for those groups. Stated otherwise, it would be extremely unfortunate if the creation of a new manatee population in Guadeloupe jeopardized the survival of another manatee population elsewhere in the Caribbean. 3 If a re-introduction were to be done, we would recommend that no more than 10 individuals be taken from the population of any country. If the estimated population for a given country were only 500 manatees, 10 individuals would represent 2% of that population. To put that percentage into some context, the annual percentage rate of increase for a stable population of Florida manatees was estimated to range between 1.9% and 6.6%, depending on the interbirth interval (Boyd et al. 1999). We assume (see below) that adult or large juvenile manatees might be preferred for the reintroduction; we further assume that the majority of the introduced individuals should be female to optimize reproductive potential. Since survival of adult females is especially important to the well-being of manatee populations, the removal of 10 adults, most of which are female, would have a greater impact than removal of calves or males of any age on the parent population from which animals are removed. We believe that 10 individuals is the smallest number that one could choose to provide a viable population in Guadeloupe, and ten is also the largest number one would want to remove from any existing population. Category 5: Status of the manatees that would be used for the re-introduction There are several issues to consider in this regard. The first, and perhaps most obvious, is whether the location where manatees would be collected can sustain the loss of several individuals. That question is addressed to some extent under Category 4, above. If the source of animals for the re-introduction is free-ranging manatees, we recommend that animals sought for translocation come from as large a population of Antillean manatees as possible, to minimize the effects on the remaining population. In that regard, consideration should be given to the following countries as sources of manatees: Belize (estimated population size = 1,000), Brazil (500), Colombia (500), Mexico (1,500), and Nicaragua (500). Countries in which 100 or fewer manatees exist would be inappropriate candidates, in our opinion, as sources of animals for the re-introduction. We think it is perhaps useful to consider using manatees that are already held in captivity, rather than wild, free-ranging manatees. For example, in northeastern Brazil, there used to be (and may still be) a number of captive Antillean manatees (mostly orphaned calves, as we recall). These animals might be good candidates for the re- introduction because: a) it would eliminate or reduce the need for removals of manatee from wild populations; b) the captive animals would be easy to assess in terms of their health and genetic make-up; and c) costs would be significantly reduced. Having said that, we want to note that using captive animals in this way can inadvertently create an impression among local people that there is a lot of money to be made by selling manatees. There have been situations elsewhere in which female marine mammals with young were killed, with a perception that there was a lucrative market for the young animals. Under no circumstances would it be appropriate to create an impression anywhere that future sales of manatees will occur for any reason. With that caveat, it may 4 be prudent for the government of Guadeloupe to inquire about the possible availability of already-captive manatees in Brazil or elsewhere.

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