By César Guerrero and Antonieta Valenzuela

The use of camera traps for capturing images of wildlife is a helpful and important tool for environmental conservation, since it provides evidence on wildlife diversity of a determined place without human interference.

This technique has gained popularity in the last years as a consequence of the rise of the new rather economic and easy-to-use automatic cameras (Kucera & Barret, 1993). They are also non-invasive and highly efficient compared to traditional techniques (Monroy-Vilchis et al. 2009).

A camera trap is an automatic device that detects movement or temperature changes (depending on the camera), and is triggered by a sensor to take a photograph. Generally, they are used to capture medium- to large-sized land mammals and some species of birds.

Broadly speaking, there are two types of cameras: triggered and non-triggered. Non-triggered cameras work by taking pictures continuously or with programed time intervals to capture events. On the other hand, triggered cameras activate with an event, usually the arrival of an animal. It can be activated mechanically, like with an animal stepping on a pressure pad, but more typically they are activated by an infrared system.

“The use of camera traps is a helpful technique to study wildlife, […] and recollect information on a range of species, simultaneous or continuously in different areas of study, during a large period of time” (Ancrenaz et al., 2012, p.2).

As to Terra Peninsular, both in Valle Tranquilo Nature Reserve and in Punta Mazo Nature Reserve, camera traps are used to collect useful information on the habitat by being an eco-friendly option that generates little to no impact.

In these nature reserves, camera traps are strategically located in the areas of study and are rotated following systematic methods according to the objectives.

Depending on the objectives and based on the obtained data, decisions focused on conservation following the Adaptive Habitat Management program are made, such as identifying changes in the ecosystem, determining presence or absence of wildlife to know in detail the biodiversity, use of habitat, among other aspects.

As a result, different species have been detected in both reserves, especially in the Valle Tranquilo Nature Reserve where pictures of cougars, bobcats, mule deer, coyotes, and gray foxes, among other species have been taken.

Chavez et al. (2013) stated that: “Detecting an individual or species […] is just the tip of a big mountain of information that allows us to analyze and understand both special aspects (distribution and abundance) and temporal aspects (if the sampling is done in several seasons) related to the changes in land mammals populations (p.45).

Even if camera traps are relatively easy to use, it is worth highlighting that the demand of installment and review camera traps is considerable, and depends on the size and logistics of the sampling areas.

Methods applied are just as important as the device: it requires logistic efforts, knowledge of the equipment, clear definition of objectives, delimitation of the area of study, consideration of the position of the sun, installment, etc. and after that, the download and detailed review of the photographic material obtained.

Just as Ancrenaz et al. (2012) explained: “The use of camera‐traps has enormous potential for the surveying and consequent management of wildlife and can be used to answer a number of important questions; […] a successful camera‐trap project is very rewarding and may return results no other survey method would have provided” (p.5).

Camera trapping has resulted in a helpful tool for nature reserves managed and protected by Terra Peninsular A.C. since it is a non-invasive option that allows collecting information and decision-making following the Adaptive Habitat Management program that is aligned to the objectives of conservation in Baja California.

References

• Ancrenaz, M., Hearn, A.J., Ross, J., Sollmann, R., & Wilting, A. (2012). Handbook for wildlife monitoring using camera‐traps. Recuperado de http://www.bbec.sabah.gov.my/japanese/downloads/2012/april/camera_trap_manual_for_printing_final.pdf
• Chávez, C., De la Torre, A., Bárcenas, H., Medellín, R.A., Zarza, H. & Ceballos, G. (2013). Manual de fototrampeo para estudio de fauna silvestre. El jaguar en México como estudio de caso. Alianza WWF-Telcel, Universidad Nacional Autónoma de México, México.
• Kucera, T. E., y Barrett, R. H. (1993). The Trailmaster camera system for detecting wildlife. Wildlife Society Bulletin, 21: 505-508.
• Las trampas cámara (s.f.). Retrieved from http://www.semahn.chiapas.gob.mx/portal/descargas/guardaparques/articulos/LAS_TRAMPAS_CAMARAS_extensos.pdf
• Monroy-Vilchis, O., Rodríguez-Soto, C., Zarco-González, M., & Urios V. (2009). Cougar and jaguar habitat use and activity patterns in Central Mexico. Animal Biology, 59: 145-157.
• Naves, J., Fernández, A., Gaona, J. F., & Nores C. (1996). Uso de cámaras automáticas para la recogida de información faunística. Doñana, Acta Vertebrata, 23: 189-199.
• O’Connell, A. F., Nichols, J. D. & Karanth, K. U. (Eds.) (2011). Camera traps in animal ecology: Methods and analyses. First edition. Springer, New York, New York, USA.