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It is necessary to assess whether the management of protected areas is achieving the objectives set for them. In particular, changes and trends in wildlife populations should be documented. We compared the 1990 abundance of mammals in two Costa Rican protected areas, Corcovado National Park (CNP) and Golfo Dulce Forest Reserve (GDFR), with similar environmental characteristics but different hunting restrictions and levels of protection. We also monitored the abundance of mammals in CNP over a 4-year period. We also devised an inexpensive method of monitoring tropical rainforest mammal populations in a timely and efficient manner. The method is based on the use of mammal track records and arboreal mammal sightings and requires little effort. With this method 20 mammal species were recorded at CNP and 15 at GDFR. Species were consistently less abundant in GDFR than in CNP, principally those species preferred by hunters. Species were grouped according to whether or not they are used as food and whether they are locally or globally threatened or not threatened. The abundance of all these groups of species in GDFR was 6-28% the abundance in CNP. During 1990During -1994, overall mammal abundance in CNP remained relatively stable, but there was considerable variability among species. As a group, both species used for food and globally threatened species declined in abundance during that period in CNP. The abundance of all groups of species declined from 1992 to 1994, coinciding with a reduction in hunting vigilance at CNP. Evidence suggests that the main factor differentiating the abundance of mammals in the two protected areas, and at CNP during the study period, was the level of hunting. Golfo Dulce Forest Reserve seems to be achieving only partial success in protecting wildlife, whereas Corcovado National Park seems to be considerably more effective, although not entirely successful. Monitoreo de Poblaciones de Mamíferos en Áreas Protegidas de Costa Rica con Diferentes Restricciones de CaceríaResumen: Es necesario evaluar si el manejo de áreas protegidas está cumpliendo con sus objetivos establecidos. En particular, se deben documentar los cambios y tendencias de las poblaciones de vida silvestre. En este estudio comparamos la abundancia de los mamíferos durante 1990 en dos áreas protegidas de Costa Rica con características ambientales semejantes, pero con diferentes restricciones en cuanto a la cacería y diferentes niveles de protección: el Parque Nacional Corcovado (PNC) y la Reserva Forestal Golfo Dulce (RFGD). También comparamos la abundancia de los mamíferos en el PNC durante un periodo de cuatro años (1990)(1991)(1992)(1993)(1994). Además desarrollamos un método barato, basado en el registro de huellas de mamíferos y en avistamientos de mamíferos arborícolas. Este método requiere de poco esfuerzo y se puede usar para dar seguimiento a las poblaciones de mamíferos selváticos de manera rápida y eficiente. Con este método registramos la abundancia de 20 especies en el PNC y de 15 en la RFGD. Todas las especies f...

The jaguar Panthera onca is threatened throughout its range and categorized as Near Threatened on the IUCN Red List. To inform conservation of the jaguar population in Corcovado National Park, Costa Rica, population size was estimated using data from a 3-month camera trap study. Individuals were identified from their coat patterns. The resulting density estimate of 6.98 ± SD 2.36 individuals per 100 km2 was lower than expected. The sex ratio was 1.33 males per female, and the minimum home ranges of two males were 25.64 and 6.57 km2. Hunting pressure on jaguar and white-lipped peccaries Tayassu pecari, the jaguar's main prey in the Park, may be responsible for the low jaguar density as space does not seem to be a limiting factor. The numbers of females may have been underestimated because of sampling bias and therefore the sex ratio obtained in this and similar studies must be interpreted cautiously. Better protection of the corridor that connects the Park with other protected areas is essential to guarantee long-term survival of the jaguar in Costa Rica.

Geographic variation in behaviour of individuals within a species is well known (Foster & Endler 1999), both across ranges (Iriarte et al. 1990) and locally (Hertz & Huey 1981). For predators, variation in prey use within a given site is often seasonal (Brillhart & Kaufman 1995), and related to changes in relative abundance and/or vulnerability of various prey (Kunkel et al. 2004). Behavioural diversity also occurs because prey behaviours vary and predators change foraging tactics, even on a daily basis (Ropert-Coudert et al. 2002).