Use of Mangroves by Lemurs
Int J Primatol
Use of Mangroves by Lemurs
Charlie J. Gardner 0 1
0 Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent , Canterbury, Kent CT2 7NR , UK
1 Blue Ventures Conservation , 39-41 North Road, London N7 9DP , UK
Despite an increasing recognition of the ecosystem services provided by mangroves, we know little about their role in maintaining terrestrial biodiversity, including primates. Madagascar's lemurs are a top global conservation priority, with 94 % of species threatened with extinction, but records of their occurrence in mangroves are scarce. I used a mixed-methods approach to collect published and unpublished observations of lemurs in mangroves: I carried out a systematic literature search and supplemented this with a targeted information request to 1243 researchers, conservation and tourism professionals, and others who may have visited mangroves in Madagascar. I found references to, or observations of, at least 23 species in 5 families using mangroves, representing >20% of lemur species and >50% of species whose distributions include mangrove areas. Lemurs used mangroves for foraging, sleeping, and traveling between terrestrial forest patches, and some were observed as much as 3 km from the nearest permanently dry land. However, most records were anecdotal and thus tell us little about lemur ecology in this habitat. Mangroves are more widely used by lemurs than has previously been recognized and merit greater attention from primate researchers and conservationists in Madagascar.
Conservation; Madagascar; Primate-habitat interactions; Refuge; Strepsirrhini
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Mangroves are forests or other vegetated ecosystems that grow in the intertidal areas of
subtropical and tropical coastlines around the world. They have attracted increasing
conservation attention in recent years, in part as a result of an improved understanding
of the ecosystem services they provide, which include carbon sequestration and storage
(Donato et al. 2011; Nellemann et al. 2009; Pendleton et al. 2012; Ullman et al. 2012),
as well as coastal protection and erosion prevention (Alongi 2008; Dahdouh-Guebas
et al. 2005). In addition, mangroves provide breeding and feeding grounds for a range
of marine species (Kathiresan and Bingham 2001; Nagelkerken et al. 2008), including
fish and crustaceans that sustain major commercial fisheries (Manson et al. 2005;
Naylor et al. 2000), and generate provisioning services for coastal human communities
in many countries (Glaser 2003; Rasolofo 1997; van Bochove et al. 2014).
Despite the increased recognition of mangrove ecosystem services, our
understanding of their importance for the maintenance of terrestrial biodiversity remains patchy
(Nagelkerken et al. 2008), and this is the case even for charismatic vertebrates such as
primates (Nowak 2012). Mangroves are marginal habitats for many terrestrial
mammals owing to their extreme and dynamic conditions, including frequent inundation,
low botanical and invertebrate diversity, and vegetation that tends to be unpalatable
because of its high tannin content (Intachat et al. 2005; Kraus et al. 2003; Nagelkerken
et al. 2008; Tomlinson 1995; Vannucci 2001). As a result, there are few obligate
mangrove specialists, such as the proboscis monkey (Nasalis larvatus), among global
primates, though at least 63 further species, including multiple species in the genera
Procolobus, Cercopithecus, Macaca, and Presbytis, among others, are known to use
this habitat facultatively (Nowak 2012): for many, mangroves may be used as a refuge
following the loss or degradation of preferred terrestrial habitats. Given that mangroves
are among the most threatened of all tropical ecosystems (Duke et al. 2007; Valiela
et al. 2001) and have lost 20%–35% of their global extent since 1980 (FAO 2007;
Polidoro et al. 2010; Valiela et al. 2001), an understanding of their role in maintaining
primate populations is essential to inform conservation planning, as well as contributing
to our knowledge and understanding of primate–habitat interactions.
Madagascar, a global conservation priority boasting unparalleled rates of diversity
and endemism among its terrestrial fauna and flora (Brooks et al. 2006; Myers et al.
2000), is among the countries where mangrove use by terrestrial species is relatively
poorly understood. With 213,000 ha of mangroves, Madagascar possesses ca. 2% of
their global area and is among the top 15 mangrove-rich countries globally (FAO 2007;
Giri 2011; Giri et al. 2011), yet research into use of the habitat by the country’s reptile,
bird, and mammal fauna remains in its infancy. Mangroves are distributed primarily
along the west coast, with only small, localized patches in the east (Fig. 1): the greatest
coverage is in the northwest, with the largest systems at Mahajamba Bay and
AmbaroAmbanja Bays (Jones et al. 2015, 2016). The mangroves are species poor, containing
only eight true mangrove species ( (...truncated)