How To Study The Horned Guan

Transcription

1 Distribution, Density and Population Status of the Horned Guan in México. Fernando González-García y Alejandro Abundis First report (Abril 1, 2005) INTRODUCTION The horned guan (Oreophasis derbianus) is a high priority species, the range of the species extends in both slopes of the Sierra Madre de Chiapas in Mexico and Guatemala. This guan inhabits cloud forest and its altitudinal range is between 1600 m and 3000 m, approximately. It has undergone a steady decline in the twentieth century as a result of the destruction of its humid montane-forest habitat, caused mainly by farming and, especially, the establishment of coffee plantations; it has also suffered from hunting, as this large, confiding bird is particularly vulnerable, and hunting pressure intensified as the number of coffee plantations increased, the bird is a source of food for the workers. In the Sierra Madre de Chiapas, the species is known to occur in 22 places, most of the records have been generated from the core zone I of the El triunfo biosphere reserve called El Triunfo. STUDY AREA AND METHODS This study was carried out in a cloud forest in the core zone I of the Biosphere Reserve El Triunfo Chiapas, México. We conducted visual and aural surveys of Horned Guan from december 2004 to March 2005 during its breeding season. We used the line transect sampling to estimate O. derbianus density and population size. We surveyed five line transects set along trails labeled every 50 m. Trails Lenght Palo Gordo 3,000 m Costa 2,800 m Cerro Bandera 2,700 m Cerro El Triunfo 1,400 m Prusia 3,000 m All transects were in a primary forest (photo 1). The visual and aural estimations were conducted simultaneously while walking to an average speed of 1 km/h. In a given day,

2 a same observer surveyed a pair of line transect selected randomly from 07:00 to 10:00, and from 14:30 to 17:30 aproximately. Each of the five transects was surveyed one time at each time of day. Photo 1. Primary forest in El Triunfo During the line transect sampling we recorded beginning and ending hour, and ambiental conditions. Sometimes the survey was not possible because the ambiental conditions were adversed (strong rain and wind). For each horned guan detected (photo 2) we recorded type of detection (visual or aural), sex (by vocalizations), age (when possible), social status (solitary or paired), hour, and the perpendicular distance to the line transect. The exact position of the bird along the transect was registered. Aditionally we registered the bird activities (when possible): roosting, feeding, flying, scaping, etc. Photo 2. Male Horned guan feeding

3 PRELIMINARY RESULTS A total sampling effort of 103,200 m ( 103 km) along transect lines was invested during the four month study. Until the moment we have the following records by sex. At December we have 2 male records and 2 females; At January 2 male records, 1 female and 1 no sexing individual; At February we gather 3 males records and 2 no sexing individual; At March, 8 male records, 6 females and 3 with no determined sex (Fig. 1). The most individuals have been seen and heard at the morning ( Fig. 2). HORNED GUANS RECORDS BY SEX RECORDS DEC JAN FEB MAR MONTHS NO SEXING FEMALES MALES Fig 1. Horned guans records by sex in each month. The daily records per month are shown in the figure 2. DAILY DETECTIONS BY MONTH RECORDS DEC JAN FEB MAR MONTHS EVENING MORNING Fig. 2

4 The trail with greater amount of records is Palo gordo (Fig. 3). At the moment, in the trail Costa have no been Horned Guan records, although it is a place where have been records in previous years. TOTAL RECORDS BY TRAILS RECORDS PALO GORDO PRUSIA CERRO BANDERA CERRO EL TRIUNFO COSTA TRAILS Fig.3 We have 30 horned guan records, which have been located in a map 1 on the five trails. III II I Records december Records january Records february Records march Campamento El Triunfo IV N W E S V Map 1. Horned Guan records on the trails (I. Palo Gordo, II. Cerro El Triunfo, III. Prusia, IV. Cerro Bandera, V. Costa

5 Is very hard to distinguish among different individuals, so most of the identification has been taking in account the horn form and some characteristic of the plumage, mainly tail and wing feathers. During the study, at least 15 different Horned Guan individuals have been observed. DISTRIBUTION: SIERRA MADRE DE CHIAPAS At February 15-17, 2005 we visited the core zone III of the Biosphere Reserve El Triunfo, known as Cerro Quetzal. In this place exist a small field station ( N, W; 1634 m elevation), and is a perturbed zone with a secondary growing forest. The days 15 and 16 from 14:30 to 17:35 and 07:05 to 10:25 respectively we walked the trail from the field station into the Monterrey (photo 3) comunity ( N, W; 2190 m elevation). The main vegetation type is a growing secundary forest with a minimal portion of cloud forest. Photo 3. Trail from Quetzal field station to Monterrey Comunity The days 16 y 17 from 14:20 to 17:40 and 07:15 to 10:20 we walked the trail to Cerro El Quetzal (photo 4). In this trail exist a patch of primary cloud forest ( N, W; 2,250 m elevation), but in the peak s top due a fire in 1998 exist a big area burned ( N, W; 2,400 elevation).

6 Photo 4. Trail to Cerro Quetzal During our walking in Cerro Quetzal trails, we did not have any visual and aural Horned Guan records. Historically, for this place exist only one Horned Guan record. It was seen in the 80 s by the staff of the reserve, near El Quetzal and Monterrey trail joint. This core zone have several problems, like a pression by human activities, at west with the Finca Cuxtepec (coffee plantation) and at east with Monterrey comunity. Furthermore, it has a big area of cloud forest burned, principally in the top of several peaks around (photo 5). Photo 5. Cloud Forest area burned in the top of Cerro El Quetzal

7 PHOTO GALLERY AND FIELD WORK IN EL TRIUNFO BIOSPHERE RESERVE: Cerro La Bandera, El Triunfo Biosphere Reserve, Chiapas, México Alejandro Abundis, Master Science Student watching a Horned Guan, La Bandera Trail.

8 Horned Guan male feeding in a Perla tree, Prusia Trail. El Triunfo Biosphere Reserve: students, field assistant and field station guards

9 CHIMALAPAS, OAXACA: Our first visit to Chimalapas zone was in March. We can not visit the cloud forest zone, because we need the permit of the communal authorities. So, most time of our March field work was used to contact to the local authorities mainly from San Miguel Chimalapas. Almost all the time, we talk and we make actions and negotiations with Mr. Cuauhtemoc Martínez, who is the responsible of the bienes comunales of San Miguel Chimalapas. As part of this communication and actions, we visit the Sol and Luna community along with Mr. Martínez. Although this communities is far away of the Cloud Forest zone, this visit and this first contact was very important for the near future. In according with Mr. Martínez, is very possible we can get the permit to visit the Cloud Forest zone, but before is very important to do a meeting with the communities live near of the cloud forest area and to explain reason of our interest in the zone. So, the next meeting will be in mid-april, so we hope to get permit and to do our Horned Guan exploration. However, during our first visit to the San Miguel Chimalapa, we can important information about the possible presence of the Horned Guan in the Chimalapas zone. Authorities and people of San Miguel Chimalapa are interested in Ecoturism program. They want to start pilot program in Sol y Luna, San Antonio and Benito Juárez communities. As a way to help the authorities of San Miguel, we offer help them with courses and training program related with birdwatching. Joining WWF-Oaxaca staff, we are organizing the first training bird guides course in rural communities. It is important to mention that we have the help and support of the World Wildlife Fund-Oaxaca staff. Without their help, try to visit the Chimalapas area it will be very hard. Welcome to San Miguel Chimalapa, Oaxaca, March 2005

10 People and my field assistant in the Sol and Luna community, San Miguel Chimalapa, Oaxaca, March, 2005 Recording bird sound in Sol and Luna community, San Miguel Chimalapa, Oaxaca. March, 2005