Original Article Densities and Perceptions of Jaguars in Coastal Nayarit, Mexico JOE J. FIGEL, 1 Department of Biology, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816, USA FERNANDO RU  IZ-GUTI  ERREZ, Laboratorio Integral de Fauna Silvestre, Unidad Acad emica de Ciencias Qu  ımico Biol ogicas, Universidad Aut onoma de Guerrero, Avenida L azaro C ardenas, Ciudad Universitaria, Chilpancingo, Guerrero 39070, M exico DAVID E. BROWN, School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ 85287, USA ABSTRACT Conservation of large carnivores will require greater analyses of population parameters, habitat use, and distribution in multiuse landscapes as human populations increase and agriculture expands. We used Bayesian spatially explicit capture–recapture (SECR) models and completed 82 interviews in 24 localities over 4 field seasons from April 2009 to March 2013 to estimate densities and assess residents’ perceptions of jaguars (Panthera onca) in the San Blas Municipality within the southern Marismas Nacionales ecosystem in Nayarit, Mexico. Camera traps accumulated 90 detections of 9 jaguars (2 M, 5 F, and 2 individuals of unknown sex) in a 194-km 2 area during 1,575 trap-nights from April to June 2010. We detected jaguars at 16 of the 27 camera-trap sites and calculated a density estimate of 2.04 (SE ¼ 0.45) individuals/100 km 2 using the SECR method. This is one of the first studies to use SECR models for jaguar density estimation and 1 of only 2 studies throughout jaguar distribution to estimate population parameters of the species where human population densities reach >50 people/km 2 . Future studies in this unique landscape should focus on jaguar status in the northern stretches of the Marismas Nacionales and research the mechanisms that may allow this large carnivore to persist in altered landscapes among human population densities greater than previously believed to be tolerable by the species. Ó 2016 The Wildlife Society. KEY WORDS capture–recapture, density estimation, mangroves, M exico, Nayarit, Panthera onca, perceptions, spatially explicit. Jaguars (Panthera onca) have been eradicated from approxi- mately 60% of their historical range in Mexico, where they are considered endangered (SEMARNAT 2002, Ch avez and Ceballos 2006). The Marismas Nacionales (hereafter, Marismas) in the state of Nayarit represents the north- ernmost semiaquatic habitat for jaguars where the species’ prey base includes American crocodiles (Crocodylus acutus) and freshwater turtles (Trachemys spp.; Brown and L opez Gonz alez 2001). Unlike jaguar habitat in the more arid states of Sinaloa and Sonora to the north that have prolonged dry seasons and <800 mm annual rainfall, the Marismas has a wetter climate and contains the largest tract of Pacific coast mangroves (Laguncularia and Avicennia spp.) in North America (Flores-Verdugo et al. 2001). Extending from the vicinity of Escuinapa, Sinaloa, to San Blas, Nayarit, Mexico, the Marismas represents approxi- mately 22% of the total mangrove cover in Mexico (Ruiz- Luna et al. 2010). Designated a Ramsar wetland of international importance in 1995 (Ramsar site no. 732; RSIS 1995), and declared a Biosphere Reserve in 2010 (DOF 2010), the Marismas has been an area reportedly associated with robust jaguar populations for more than half a century (Leopold 1959, McCurdy 1979, Carmony and Brown 1991, Brown and L opez Gonz alez 2001, Brown and Thompson 2010). Leopold (1959) identified coastal Nayarit as 1 of 4 areas in Mexico believed to contain the greatest densities of jaguars anywhere in the country. However, Nayarit’s mangroves and tropical dry forests (TDF) have undergone extensive deforestation and its highway network has expanded since Leopold’s surveys in the 1950s (Kramer and Migoya 1989, Ram  ırez-Garc  ıa et al. 1998). The opening of an artificial channel—Canal de Cuautla—in 1972 drastically altered salinity in the Marismas, from predominantly freshwater–brackish to marine, result- ing in the death of 24% of the white mangrove (L. racemosa) and black mangrove (A. germinans) forests (Flores-Verdugo et al. 2001). From the 1970s to 2005, the Marismas lost >10,000 ha of mangroves—about 13% of its total extent (Ruiz-Luna et al. 2010). Much of the southern Marismas is now covered by expansive private-sector shrimp farms (Berlanga-Robles and Ruiz-Luna 2006) and construction of a new highway is ongoing. Despite the loss of mangrove vegetation communities and expansion of paved roads, coastal Nayarit was classified as 1 of 9 Priority II regions for jaguars in Mexico—areas that Received: 11 March 2015; Accepted: 27 June 2016 1 E-mail: jj.figel@knights.ucf.edu Wildlife Society Bulletin; DOI: 10.1002/wsb.686 Figel et al.  Densities and Perceptions of Jaguars 1