Introduction

The understanding of the historical and current distribution of each species is valuable to determine the biotic and abiotic factors that have affected their geographical distribution in space and time, specifically in species with lower tolerance to human pressure, and vulnerable to human impact (^{Prugh et al., 2008}; ^{Torres-Romero and Olalla-Tárraga, 2014}). Some wild mammal species are more susceptible than others to anthropic pressures (i.e. human population density, loss and habitat fragmentation), which is frequently manifested as population isolation and sometimes reaches local or global extinction of the taxon (^{Cardillo et al., 2005}; ^{Prugh et al. 2008}; ^{Olalla-Tárraga et al., 2015}).

Terrestrial mammal species with opportunistic and generalist behaviors can inhabit environments (i.e. pine forests, tropical forests up to deserts and scrubland), and various habitats modified by man (i.e. cultivation and livestock production areas, urban and suburban zones). These species are tolerant, adapt easily to human disturbances, and have outstanding environmental plasticity (^{Hidalgo-Mihart et al., 2004}; ^{Valenzuela-Galván, 2005}).

The state of Chiapas, Mexico, is characterized for its great mammal biodiversity since it is home to 205 terrestrial species (^{Naranjo et al., 2005}). This state faces significant changes in the modification of the landscape from loss and fragmentation of its forest covers, causing diverse habitats and areas with differential degree of disturbance. Forest exploitation is an anthropic activity, which can directly affect the presence of terrestrial vertebrates, such as wild mammals; some of them can tolerate and coexist with this activity, although others tend to disappear. However, in the state of Chiapas there are private plots like “Los Ocotones” that promote forest management with native vegetation to maintain the high tree cover and conserve broad forested areas, to keep the connection with other vegetation remnants of biological and ecological importance (i.e. Biosphere Reserve “El Ocote” and Biosphere Reserve “La Sepultura”). Therefore, it is relevant to document whether the zones with active forest management (i.e. Los Ocotones) can be considered as an area to record terrestrial mammal species of importance for conservation and which could connect other natural protected areas of the region. In Los Ocotones, approximately 10 thousand m³ per year of wood are extracted (Gómez-Jiménez, 2011⁴); this rate of exploitation can have a negative differential impact on the wild flora and fauna of the region.

Because of this, understanding the presence of terrestrial vertebrates in areas with some degree of human disturbance will allow designing conservation strategies for species in environments fragmented by anthropic activities. Los Ocotones has records of tracks and sightings of wild mammals reported by Los Ocotones workers and owner. Therefore, the objective of this study was to update the information and confirm the presence of additional wild mammal species in the forest management unit Los Ocotones, where wood is extracted and management projects are implemented for the conservation of wildlife.

Materials and Methods

Study area

Los Ocotones (16° 38' 59" N and 93° 47' 59" W) occupies 2400 ha, it is 36 km from Cintalapa, Chiapas, and 50 km SE of the Biosphere Reserve La Sepultura, and NE of the Reserve El Ocote (Figura 1). The area is part of a large mass of vegetation, which is considered to be in good shape of conservation, known also as Selva Zoque. This includes the sierras such as Sierra Atravesada in Oaxaca and Sierra Madre in Chiapas, also with well-conserved vegetation areas in Mexico (^{Lira-Torres et al., 2012}). In addition, Los Ocotones is certified by Rainforest Alliance organization for its sustainable forest management. The climate is warm-humid with annual temperature of 18 to 22 °C, May is the warmest month with 18 °C, and the annual precipitation varies from 1000 to 1800 mm (^{Arriaga et al., 2000}). The average altitude ranges between 1,000 and 1,220 masl (^{INEGI, 2005}). The vegetation in the plot is diverse, although the pine-oak forest, the oak-pine forest and the sub-deciduous tropical forest predominate (^{Rzedowski, 1978}); from these, the pine forest is the one most exploited.

Figure 1 Natural areas and location of forest management unit: Los Ocotones, Chiapas, Mexico. 

Results and Discussion

The sampling effort totaled 5,850 trap-days and 516 photographs. Of these, 42 corresponded to the additional record of nine species of terrestrial mammals, which were not confirmed in “Los Ocotones” management unit. These included jaguar (Panthera onca), tapir (Tapirus bairdii), grison (Galictis vittata), tayra (Eira barbara), ocelot (Leopardus pardalis), margay (Leopardus wiedii), jaguarundi (Puma yagouaroundi), cougar (Puma concolor), and coyote (Canis latrans) (Table 1, Figure 2 and 3). These photographic records were compiled in a pine-oak forest between 1000 and 1200 m of altitude. In addition, the camera traps recorded other terrestrial mammal species, which had already been identified and confirmed, through tracks and sightings, by Los Ocotones workers and owner (Table 1).

Figure 2 Images of wild-feline in the forest exploitation area “Los Ocotones”, Chiapas, Mexico, obtained with camera traps. A) margay (Leopardus wiedii), B) cougar (Puma concolor), C) jaguarundi (Puma yagouaroundi), D) ocelot (Leopardus pardalis), and E) jaguar (Panthera onca). 

Figure 3 Images of terrestrial mammals in the forest management area “Los Ocotones”, Chiapas, Mexico, obtained with camera traps. A) coyote (Canis latrans), B) tapir (Tapirus bairdii), C) tayra (Eira barbara) and D) grison (Galictis vittata). 

The camera traps are a non-invasive and efficient tool to record nocturnal animals, elusive and of difficult visualization (^{Torres-Romero et al., 2017}). Information about ecologic, biologic, and behavioral aspects of the species is also obtained with the cameras (^{Maffei et al., 2002}). In this study, the cameras allowed confirming the presence of nine species of mammals, of which seven are in the category of risk, as endangered or threatened (^{NOM-059-SEMARNAT, 2010}).

Although the effects of human activity on biodiversity (i.e. gradual reduction of the distribution area, hunting and illegal traffic, fragmentation and habitat loss) are perceptible in temporal and spatial scales (^{Cardillo et al. 2005}; ^{Torres-Romero and Olalla-Tárraga, 2014} y ²⁰¹⁵), this study contributed the first photographic records that evidence the presence of nine species of wild mammals in Los Ocotones. Therefore, despite this small area is being subject to anthropic pressures of forest exploitation, it is still adequate for the persistence of species with spatial requirements. In addition, the area can be considered a biological corridor connecting other forests with state interest, such as the Biosphere Reserves El Ocote and La Sepultura in Chiapas, Los Chimalapas in Oaxaca, and the region of Uxpanapa in Veracruz, recognized for their importance for the conservation of regional biodiversity.

Therefore, the conservation of biological corridors, such as Los Ocotones, is essential for maintaining the connectivity between the ends and avoiding the population isolation of the species (^{Grigione et al., 2009}; ^{Álvarez-Icaza, 2013}). Thus, the following stands out:

The presence of species such as Galictis vittata, Leopardus pardalis, Leopardus wiedii, Panthera onca, Puma yagouaroundi, Eira barbara and Tapirus bairdii with some degree of conservation protection declared by the Mexican government, recorded in the management unit Los Ocotones, confirms that the coexistence between humans and these mammals is possible. Therefore, more detailed studies could be performed, in space and time, to evaluate the impact of the forest management practices on population dynamics, primarily of the species that are qualified with some degree of risk in Mexico.

Conclusions

The use of camera traps allowed updating the information of terrestrial mammal species that are difficult to visualize and confirm the presence of priority species in Los Ocotones. The photographic records are evidence that efforts should be made in this management unit to conserve the species reported in this study, and other terrestrial vertebrates that the unit could house.