ISSN 1517-6770 Camera traps used on the mastofaunal survey of Araras Biological Reserve, IEF-RJ Luiz Cláudio Pinto de Sá Alves1 & Artur Andriolo1,2 ABSTRACT: Mammal studies in their natural habitats are generally complicated due to many factors such as difficulties in visually locating and capturing animals. Camera traps have been used in some cases, especially to study forest animals, with many purposes. The present paper reports the utiliza- tion of camera traps to survey mammal species at the Araras Biological Reserve (RBA-IEF), in Petrópolis, RJ, Brazil, from September of 2002 to January of 2003. Industrial and manufactured equipments utilizing food bait to attract the animals were used. Photographs obtained were ana- lyzed to identify the species as well as other studies: mark and recapture model, equipments efficiency, activity period and other behaviors. Ten species of mammals were photographed, besides some other species that were observed, but not photographed. The camera traps proved to be efficient: to survey some mammal species; to study activity period and other behaviors; to evaluate the conservation status of the area. Key Words: Camera trap, survey, mastofauna, Araras Biological Reserve. INTRODUCTION Mammal studies in natural environments are generally complicated due to difficulty in visualizing and capturing animals. Faunal inventories requires technology that allows surveying the majority of the species (SANTOS-FILHO & SIL- VA, 2002) in the area of interest. Even with the aid of modern equipment such as radio tags and image amplifiers, field mammalogists still need to improve expertise in detecting and interpreting the signs of where their animals have been (MAR- TIN, 1990). The camera trap is a relatively new alternative to study wild animals and has been extensively applied in fieldwork studies. For example, KARANTH et al. (2003) used this 1 Mestrado em Ciências Biológicas – Comportamento e Biologia Animal. ICB, Universidade Federal de Juiz de Fora, Campus Universitário, 36036- Rev. bras. 900, Juiz de Fora, MG, Brasil. [email protected] Rev.Zoociências bras. 2 Departamento de Zoologia, ICB, Universidade Federal de Juiz de Fora, ZoociênciasJuiz de Fora JuizV. 7 de Nº Fora 2 Campus Universitário, 36036-330, Juiz de Fora, MG, Brasil. V.Dez/2005 7 Nº 2 [email protected] Dez/2005p. 231-246 231 Camera traps used on the technique on field works with big felids and other animals, to mastofaunal survey of estimate densities and other parameters. Also, MAIN & Araras RICHARDSON (2002) utilized camera traps for monitoring Biological Reserve, wildlife recovery on a pine tree forest at different after-fire IEF-RJ periods, and YASUDA & KAWAKAMI (2002) utilized them on an internet-based wildlife monitoring, automatically photographing animals when detected. Some studies also used these equipments on tigers (Panthera tigris) (Linnaeus, 1758) mark and recapture methodology, where different body stripes patterns were used to individually identify the photographed individual (CARBONE et al., 2001, KARANTH & NICHOLS, 1998). By individually identifying the tigers, they were able to make an estimation of densities of the animals. Similar methodology was also used by GLEDHILL et al. (1996), on a marine life monitoring, using video camera traps that were installed at 9 to 110 meter depths, and recorded small periods of the animals behaviors. PRIEDE et al. (1994) used underwater photographic traps on a demersal fishes survey. Manufactured camera traps were successfully utilized on previous studies; MARQUES & RAMOS (2001) verified the occurrence of rodents, deers and carnivores at the São Francisco de Paula National Forest/IBAMA, RS State, using three of these equipments. VOSS & EMMONS (1996) suggested the use of photography surveys only for median and big size mammals. This technique has been expanded because of its applicability in situations where the observer presence may cause interference in the results. It is possible because it implicates in low stress to the photographed animals. The data obtained can be used to monitor populations, especially because little is actually known about the status of populations at the conservation units in Brazil (CAMARGO et al., 2002). The main objective of this study was to perform a description of the actual situation of the Araras Biological Reserve’s mastofauna, by utilizing camera traps to survey the mammal species that occurs in the area. Secondary objectives were: study the activity period pattern of some species as well Rev. bras. as other behaviors; compare efficiency of the equipments used. Zoociências Juiz de Fora V. 7 Nº 2 Dez/2005 p. 231-246 232232 Luiz Cláudio MATERIAL AND METHODS Pinto de Sá Alves, Artur Study Area Andriolo The Araras Biological Reserve (Reserva Biológica de Araras-RBA)-IEF/RJ, located in Petrópolis and Miguel Pereira districts, is restricted in use due to its conservation status. It is a 2,048 ha area, and it is covered by Atlantic Forest stretches in different degrees of recovery, being some of them represented by climax species that composes areas of primary vegetation (GOVERNO DO ESTADO DO RIO DE JANEIRO, 2001). The RBA is located in the Serra do Mar and forms an ecological corridor, along with another eight conservation areas. Camera traps Two kinds of camera trap were utilized between September of 2002 and January of 2003: two Buckshot equipments, model 35-A and two similar manufactured equipment; both digitally mark the day and time when the respective photographs were taken. In September two manufactured equipment were used, and in the following months two Buckshot and two manufactured traps were used. The study was interrupted for 30 days in October due to a major forest fire that occurred in the period. The total sampling effort equaled 5,304h. The Buckshot equipment is composed by an acrylic box with removable posterior cover and front glass openings for the photographic lens and inlaid flash, beyond a heat sensor exit opening. This system carries out automatic photographic registers, set in motion by interrupting a beam of infrared rays (due to the bodies heat). The passive infrared sensor is connected to a timer circuit through a tripolar cable. The time between a photo and another one is at least of one minute, which allows the recharge of flash between photos. The entire system uses two 9-volts batteries plus two AA batteries for the flash. The equipment was fixed on trees of different diameters by an elastic band, approximately 30cm off the ground. This allows sampling of animals of a variety of sizes. The manufactured equipment functions similarly to the Buckshot equipment, but the camera is located externally to the rest of the system. A small acrylic Rev. bras. Zoociências box, with only one front exit (for the heat sensor), contains the Juiz de Fora V. 7 Nº 2 timer circuit hardwired to a presence sensor. A galvanized brass Dez/2005 box protects the camera. The passive infrared sensor, when p. 231-246 233233 Camera traps used on the registering an increase of temperature, stimulates the internal mastofaunal survey of circuit, which orders an electric stimulation to the camera, from Araras an adapted cable, activating the photographic device. This Biological Reserve, system utilizes a 9 volts battery and 5 AA batteries. Both cameras IEF-RJ uses 35mm lens, inlaid flash, automatic focus and a motor drive. ASA 100 to 400, 35mm, 36 exposure films were used. Sampling Locations Eight sampling locations of the RBA were established, with distances from the central office varying from 20m to 2.249km. Different niches were chosen as sampling locations, with the aim of registering the largest number of species as possible: close to rivers or far from it, close to human habitations (central office) or far from it and inside rocky caves. All the selected sampling locations geographic’s positions were determined using a Global Positioning System (GPS). Animals were attracted by food bait composed by vegetables, meat, peanut cream and sardine. This bait was placed on the ground, 2 meters away from the camera. The systems were permanently functional and were inspected twice a week. Data Analysis The photographs were used to identify species, correlating them to the timetable and place where they had occurred, amongst other informations. The permanence of the traps in each place varied from 4 to 55 days. Recaptures for the individually identifiable animals were evaluated, excluding additional registers of the same individu- al that occurred in the same occasion (same hour, same day and same place). For some species, a study of the activity period was performed using the timetable of registers of each one. Twenty four-hour temporal series were built with values of discriminative frequency (presence and absence of the species in the hour of the day) for each species. The relative frequency of occurrence was calculated for each species in the eight selected points by dividing the Rev. bras. number of records for each species in different days by the Zoociências Juiz de Fora number of effort days. The frequency of occurrence was used V. 7 Nº 2 Dez/2005 to compose the plexogram. The photographic occurrences were p. 231-246 classified as diurnal, when occurred between 06:00 and 17:59, 234234 Luiz Cláudio and nocturnal, when occurred between 18:00 and 05:59. The Pinto de Sá Kruskal-Wallis test was applied to compare the frequencies of Alves, Artur Andriolo occurrence of the species in the total sampling period. For both photographic systems, the functioning efficiency was calculated dividing the useful photos (photos containing photographic record of an animal) by the amount of photographs taken off, obtaining then the frequency of effectiveness of each system. The efficiency index was compared using an F test. RESULTS Photographed animals A total of 235 animal photos were registered, called here of useful photos, being 190 photos took out by manufactured equipment and 45 by the Buckshot equipment.