Camera trapping Priodontes maximus in the dry forests of Santa Cruz, Bolivia.

Abstract

During systematic camera trapping surveys conducted for jaguars, we collected photographs of giant armadillos at three of four dry forest (Chaco and Chiquitano) sites surveyed in eastern lowland Bolivia, thus extending the documented distribution of the species. The cumulative 30 camera trap records with time information suggest a highly nocturnal activity pattern. We identified individuals according to the distinct scale patterns, particularly the dividing line between dark and light scales on the carapace and hind legs. We estimated crude densities, ranging from 1-16 individuals/ 100 [km.sup.2] across sites and surveys, by dividing the number of individuals by the area enclosed by the camera traps. At one site the number of captures and recaptures was sufficient to estimate abundance using the software Capture, together with a survey area that includes a buffer area around the camera traps equivalent to half the mean maximum distance covered by individual animals observed at more than one camera trap location. Together these estimates suggest a population density of 5.77-6.28/100 [km.sup.2] for this site. Given the vast area (11,500 [km.sup.2]) of similar habitat protected within the Kaa-Iya National Park, and preliminary evidence of the species in neighboring protected areas, the dry forests of eastern Santa Cruz may offer a unique stronghold for the long-term conservation of the species.

Resumen

A traves de estudios sistematicos de uso de trampas de camaras por jaguares, hemos recogido fotos de armadillos grandes en tres de los cuatro sitios de los bosques secos (Chaco y Chiquitano) estudiados en la tierra baja oriental de Bolivia, aumentando asi la distribucion documentada de la especie. Los 30 archivos acumulados de las trampas de camara, que incluyen informacion sobre la hora del dia cuando fueron utilizadas, sugieren un patron de actividad nocturna muy alto. Hemos identificado individuos de conformidad con las distintas configuraciones de las escamas, en particular, la linea divisoria entre las escamas oscuras y claras en el caparazon y patas posteriores. Estimamos las densidades brutas, que van de 1 a 16 individuos/ 100 [km.sup.2] a traves de los sitios y estudios, dividiendo el numero de individuos entre el area cubierta por las trampas de camara. En uno de los sitios, el numero de individuos capturados y recapturados fue suficiente para estimar abundancia, usando el programa CAPTURE; y considerando una zona "buffer" alrededor las trampas de camara equivalente a la mitad de la distancia maxima promedio cubierta por los animales observados en mas de una de las trampas de camara. Como resultado, estimamos una densidad de poblacion de 5.77 - 6.28 / 100 [km.sup.2] para este sitio. Tomando en cuenta la enorme zona (11,500 [km.sup.2]) de habitat protegido dentro del Parque Nacional Kaa-Iya, y la evidencia preliminar de especies en areas protegidas cercanas, los bosques secos de Santa Cruz oriental pueden ofrecer un refugio unico para la conservacion de largo tiempo de esta especie.

Introduction

The giant armadillo, Priodontes maximus, is considered to be rare throughout its geographic distribution, and endangered (EN A1cd, IUCN 2002; Appendix I, CITES 2003) from continued habitat conversion and hunting. Its scarcity, combined with nocturnal and largely fossorial habits, have made it a difficult species to study in the field. It is known to live in a variety of Neotropical lowland habitats, from humid to dry forests and grasslands, and to feed on ants and termites, often destroying their large nests (Eisenberg and Redford 1999; Emmons and Feer 1999). Knowledge about its ecology derives mainly from indirect signs, sporadic sightings or dead animals, while its abundance and ranging behavior are largely unknown.

As a result of an intensive camera trapping study focused on jaguars, we obtained a number of automatically-triggered pictures of giant armadillos from the dry forests of Santa Cruz, Bolivia. In this article we describe the use of camera traps, present novel trapping data on giant armadillos, and discuss their contribution to the knowledge of activity patterns, abundance, ranging behavior, distribution and conservation status of this species.

Study area

1. Kaa-Iya del Gran Chaco National Park (see Figure 1): This 34,400 [km.sup.2] protected area covers the northern end of the Gran Chaco, including four principal landscape systems (Navarro and Fuentes 1999). The two purely Chacoan forest landscape systems are the Chaco alluvial plain forest (13,800 [km.sup.2]) and the Chaco riverine forest (500 [km.sup.2]). The two other landscape systems are transitional forests: the Chaco transitional landscape system (9,100 [km.sup.2]) and the Chiquitano transitional landscape system (11,500 [km.sup.2]).

[FIGURE 1 OMITTED]

1.a. During 1997, we established a field camp at Cerro Cortado (19[degrees] 31.60' S, 61[degrees] 18.60' W) in the Chaco alluvial plain landscape system, on the border between the Kaa-Iya National Park and the adjacent Izoceno indigenous territory. Annual precipitation at the site averages 500 mm. During the 6-8 month dry season, surface water disappears for extended periods. A single road runs through the study site, unused for over a decade until we reopened it to establish our research camp. We opened a grid of 2-4 km study trails off of the road. The area is not subject to hunting or livestock pressure.

1.b. Towards the northern end of the Chiquitano transitional landscape system we established a field camp in 2001 at Tucavaca (18[degrees] 30.97' S, 60[degrees] 48.62' W), on the Bolivia-Brazil gas pipeline and 85 km south of the town of San Jose de Chiquitos. Annual precipitation at the site averages 800 mm. During the six month dry season, surface water disappears for extended periods. Existing roads include the gas pipeline itself (30 m-wide right-of-way, with a 3-6 m-wide road to one side or in the center), a gravel road north to San Jose, and an overgrown road south to Paraguay. We opened a square grid of 5 km study trails, enclosing a 100 [km.sup.2] study area centered on the field camp and the gas pipeline, and added in 2002 an inlaid 2 km x 2 km grid of trails. Scrub patches remain where the forest was burned roughly 30 years ago, and the area is not subject to hunting or livestock pressure.

1.c. Also in 2001, we established a second field camp towards the southern end of the same landscape system at Ravelo (19[degrees] 17.72' S, 60[degrees] 37.23' W), near the Paraguayan border. Annual precipitation at the site averages an estimated 650 mm, but, unlike the previous site, water points (springs, lagoons) persist year-round in all but the driest years. The springs cluster around the Cerro San Miguel that rises 500 m above the surrounding plain, while a salt pan also lies within the study area. A single road crosses the area, from the city of Robore to the northeast, passing through Ravelo military outpost, on to Paraguay. Several overgrown roads also exist, unused for over 10 years: one leads west to the large salt pans within the Kaa-Iya National Park and from there north to Tucavaca and San Jose, others were opened in a grid of oil exploration lines. We reopened several of these roads as footpaths/study trails, as well as cutting additional new study trails 3-5 km long to cover the study area. The dozen soldiers at the Ravelo military outpost maintain a small number of cattle (30) and several donkeys, while the nearest cattle ranch 15 km to the southeast at Palmar de las Islas maintains roughly 300 cattle. Livestock is not fenced in and therefore strays between Ravelo and Palmar along the main road.

2. The San Miguelito Private Reserve comprises approximately 25 [km.sup.2] within a 400 [km.sup.2] cattle ranching property 200 km to the east of Santa Cruz, and north of the Kaa-Iya National Park (17[degrees] 05.52' S, 61[degrees] 47.32' W). The landscape system is Chiquitano dry forest, with an average annual rainfall from 1000 to 1500 mm, and vegetation types ranging from sub-humid forest to 'cerrado' woodland (Rumiz et al. 2002). Cattle ranching is the principal economic activity outside the private reserve itself, with patches of forest cleared for pasture. The ranch maintains a system of roads through the reserve, in addition to which we opened a number of study trails 1-3 km in length. A small river runs through the private reserve, and several permanent springs along the 200 m escarpment running parallel to the river, as well as artificial ponds, provide surface water for wildlife.

Methods

The methodology at all sites consisted of a systematic camera trap survey, whose primary objective was to survey jaguars (Panthera onca) and to estimate their population densities (Maffei et al. 2002, in press, under review, Silver et al. in press). We used Camtrakker[R] and Trallmaster[R] camera traps with passive and active infrared detection systems. Sensors detect movement or changes in temperature from the presence of an animal, and activate the camera trigger. The cameras automatically recorded the date and hour on each photograph. Cameras were active continuously (24 hours a day), although a few were reprogrammed to avoid self-firing during the hottest hours of the day. We set them in pairs facing each other across a trail/road in order to simultaneously photograph both sides of any animal passing between them along the trail/road, with a distance of 1-2 km between camera sets. They were checked for correct functioning every 3-7 days, and reloaded with film (ASA 200 or 100) or batteries if necessary. All stations with at least one active camera per night were added up to calculate sampling effort in 'trap-nights'.

At Tucavaca, during eight months (May-December, 2001), we rotated 12 camera traps among sites on the study trails and the gas pipeline, for a total of 2,520 trap-nights. During an intensive 60-day survey period (19 January-20 March 2002), we installed 32 pairs of camera traps on the same study trails and pipeline road, for a total of 1,920 trap-nights. We conducted a second intensive 60-day survey from 12 April-12 June 2003 with 26 pairs of camera traps using the western half of the 10 x 10 km grid, the inlaid 2 x 2 km grid of trails, and the pipeline road, for a total of 1,560 trap nights.

In four 50 x 30 m grids where fresh giant armadillo burrows and tracks were observed, we set an additional seven cameras during three months (April-June 2002) at the burrows and along the trails themselves, for a total of 654 trap nights. Following the second intensive survey, we have continued monitoring trails with these seven camera traps (270 trap nights to August 2003).

At Ravelo, we also rotated 14 camera traps among sites on the study trails and at seasonal ponds, for a total of 1,248 trap-nights. During an intensive 60-day survey period (10 February-10 April 2003), we installed 37 pairs of camera traps on the same study trails, as well as the main road, at seasonal ponds, and a salt pan, for a total of 2,170 trap-nights. We conducted a second intensive survey using 22 pairs of camera traps across the same area (September-November 2003), for a total of 1,320 trap-nights.

At San Miguelito we conducted an intensive 60-day survey (20 September-20 November 2002), installing 22 pairs of camera traps on existing roads and study trails. We installed four pairs of cameras along the edge of the river, one pair at a salt lick, and one pair at a spring. Trapping effort totaled 1,695 trap nights.

We registered the date and camera trap location on each roll of exposed film and processed film in batches. All relevant pictures were scanned and printed, associating in pairs photographs taken by paired cameras of each single event (same animal, date, hour, and location). To calculate capture frequency we divided the number of captures by the sampling effort with the result expressed as captures per 1,000 trap-nights.

Individual animals were identified by looking at paired photos to detect particular features or marks and by comparing them with photos from other locations and dates. The minimum number of different individuals per site was determined for each survey period and used to estimate abundance. A crude estimate of density was obtained by dividing this number of Individuals by the area enclosed by the camera traps.

A more elaborated analysis was performed with the program CAPTURE (Rexstad and Burnham 1991) for the single site with sufficient observations. Assuming a dosed population during each sampling period, we estimated abundance based on captures and recaptures of identified individuals. In order to estimate the population density we divide the estimated abundance by the effective sample area. The effective sample area included a circular buffer around each station, whose radius was half the mean maximum distance among multiple captures of individuals at the site.

Results

Camera trap records and activity patterns

After a total effort of over 17,000 trap-nights, distributed across four sites (Table 1), we obtained 33 records of Priodontes maximus. As previous hunter reports and lack of animal signs had suggested, no record of Priodontes was obtained in Cerro Cortado. Cumulatively, Tucavaca rendered 29 records, San Miguelito 3, and Ravelo 1. The highest capture frequencies come from Tucavaca, but are only 4-6 per 1,000 trap nights. Combining records across sites, camera trap records indicate that giant armadillo activity patterns are decidedly nocturnal, beginning at 22:00, with only one day-time record (3%) to date (Figure 2).

Individual identification and abundance

The unique scale patterns permitted the identification of individual animals, while the genitalia were infrequently shown and did not permit us to sex every individual. The dividing line between dark and light scales on the carapace and on the hind legs was particularly noteworthy, as was the number of light scales per row from the lower edge of the carapace up to the dividing line (Figure 3). Based on these differences, we identified eighteen Individuals at Tucavaca (8 males, 1 female, and 9 unsexed), and two unsexed individuals at San Miguelito. The sole individual photographed at Ravelo was a female.

[FIGURE 3 OMITTED]

Comparing the number of individuals identified during each survey period with the area enclosed by the camera traps, we estimate crude densities of 5-7 animals/ 100 [km.sup.2] at Tucavaca (Table 1). Though fewer individuals were observed at San Miguelito, the smaller survey area suggests a slightly higher population density of 8 animals/100 [km.sup.2].

Combining all Tucavaca records during 28 months, we estimate a minimum abundance of 18 different individuals in a study area of 130 [km.sup.2], suggesting a density 14/100 [km.sup.2] if all animals survived and remained in the area. However, most individuals were observed on a single occasion, with only four individuals observed 2-3 times each over 1-3 month periods, and a single animal observed four times over a 7-month period.

Ranging patterns and density estimation with CAPTURE

The small number of individuals "captured" (N=6) and "recaptured" (N=2)during the first systematic survey at Tucavaca was sufficient to estimate a population abundance of 12 ([+ or -] 20.83) individuals using the program CAPTURE's heterogeneity model M(h). As a proxy for home range, which is unknown, we used the mean maximum observed distance (3.73 km, range 0.7-7.5 km), for individuals observed at more than one location during the entire camera trapping period (N=4). We divided this average in half in order to estimate a 1.86 buffer around camera trapping points during the systematic survey, and in turn to determine a discontinuous survey area of 191 [km.sup.2] (Figure 4). Finally, to estimate population density, we divided the population abundance by the survey area, obtaining a value of 6.28/100 [km.sup.2] (SE [+ or -] 2.76).

[FIGURE 4 OMITTED]

During the second systematic survey at Tucavaca we recorded only four individuals with three recaptures. The estimated population abundance using CAPTURE M(h) is 6 ([+ or -] 2.12) individuals, though the data are ill-conditioned. Only one individual was photographed at two sites, separated by a distance of 2.3 km. Combining the mean maximum distance with those from the previous survey, we estimate a buffer of 1.72 km (N=5), and a nearly continuous survey area of 104 [km.sup.2], The resulting density estimate from this second survey is 5.77/100 [km.sup.2] (SE [+ or -] 1.95).

The small number of captures at San Miguelito does not permit an abundance estimate using CAPTURE. For the single individual observed twice, the distance between observations was 1.34 km. Applying instead the more conservative 1.22 km average buffer observed at Tucavaca to San Miguelito, we have an approximate survey area of 48 [km.sup.2] with two observed individuals, and a tentatively estimated population density around 4 animals/100 [km.sup.2].

Multiple records of six individuals at Tucavaca showed maximum movements of 2-7.5 km for three males, 1 km for a female, and 0.7 km for an unsexed individual. For the single (unsexed) individual observed twice at San Miguelito, the distance between observations was 1.34 km. For two male individuals at Tucavaca, we are also able to estimate minimum observed home ranges based on the minimum convex polygon uniting the points (N=3) where each animal was recorded: 3 [km.sup.2] for the first animal from February-March 2002, and 15 [km.sup.2] for the second animal between August 2001 and March 2002 (Figure 4). Within this range we observed at least two other individuals during the same 7-month period. Out of the 20 locations where we observed giant armadillos, three registered multiple individuals: a maximum of three individuals during a two-month survey period, and four individuals over 28 months. These cases included spatial overlap among 2-3 males, as well as between a male and a female individual.

These multiple observations, and indeed all observations of giant armadillos at Tucavaca, occurred both on study trails as well as on the gas pipeline right-of-way road. No animals were recorded revisiting open burrows. At San Miguelito and Ravelo, all observations occurred on roads, with none at camera traps located on study trails, at springs, or salt licks.

Discussion

Camera trapping as a method to study giant armadillos

Camera trapping provides a new method for monitoring Priodontes maximus, permitting the identification of individuals and a description of their ranging behavior, and in turn the estimation of population densities. Although the systematic sampling reported here was designed to survey jaguars (trap spacing 1-2 km, location on roads--Silver et al. in press; Maffei et al. in press), it succeeded in obtaining important records of the rare giant armadillo. The sampling effort was high (~15,000 trap nights), representing perhaps an exaggerated cost for a single species study, but a cost-efficient method if considered as part of a wider survey. The intent to increase capture probabilities by targeting areas where burrows and tracks had been observed failed, with only one photograph of a giant armadillo resulting through this effort. Ideally, density estimates should be derived from surveys designed according to species specific information at the particular site (like home range) to determine camera trap spacing and continuous survey areas, and behavior to identify high probability locations for camera placement. We therefore consider our results on giant armadillo densities to be preliminary and tentative. However, as for many species at many sites, we lacked detailed range and behavioral information on giant armadillos in dry forests.

With respect to activity patterns, the number of observations is low, but 24-hour monitoring with camera traps would appear to be an objective method for assessing activity patterns (unless the animals only use roads and study trails at certain periods), and the data are consistent with the nocturnal habits reported in the literature (Eisenberg and Redford 1999; Emmons and Feer 1999; Parera 2002).

Individual identification based on differences in scale patterns from photos proved reliable. Though even at Tucavaca, where we registered the most observations, the number of captures and recaptures was small during 60-day survey periods, it was sufficient to estimate a population abundance using CAPTURE. With a small number of Individuals captured at multiple locations, the estimate of the buffer and the effective survey area is also tentative. Nevertheless, the similarity between the two density estimates at Tucavaca, based on surveys over a year apart, in dry versus wet seasons, and based on different camera trap lay-outs and survey areas, would appear to validate the method.

Capture frequencies per 1,000 trap-nights might also be used to estimate abundance, particularly when comparing systematic survey efforts, as they coincide more or less with the number of individuals observed per site and per survey effort. However, the area sampled would presumably affect the number of individuals observed, for example comparing San Miguelito with Tucavaca, and comparisons across sites should be made with caution. Trap location may influence capture success by species (Rumiz et al. 2003; Maffei et al. in press): studies with different target species may emphasize different trap locations, In turn affecting capture rates of both target and non-target species. More specifically, capture rates resulting from systematic sampling geared towards species with dissimilar habits (e.g. jaguar vs. smaller carnivores) or directed to species-specific resources (active burrows, fruiting trees, salt licks) should not be compared out of context. Moreover, the rarer the species, the greater the sampling effort necessary to obtain sufficient records for density estimates.

Camera trapping data on giant armadillo ecology

These records represent an important range extension for the species in Bolivia, compared to museum records compiled by Anderson (1997) and Eisenberg and Redford (1999), and hunting and track records (Wallace and Painter in press) from more humid lowland Amazonian forests to the north. Our camera trapping records confirm the species' presence in dry forests that include the Chiquitano forests as well as their transitional forms to Chaco forests. Our surveys also appear to confirm its absence in the driest Chaco alluvial plains at Cerro Cortado, with nearly 4,000 trap nights of effort surpassing the 1,000 trap nights that Carbone et al. (2001) estimate necessary to confirm absence. However, our single capture in over 4,700 trap nights at Ravelo suggests that animals occurring at very low densities may not be detected even with high levels of camera trapping effort, as indicated by Jennelle et al. (2002).

Giant armadillos evidently use both roads and trails, though only for short distances according to track observations. The limited information provided by camera trapping on ranging patterns and individual spacing suggests that several individuals may use the same area, not showing strict territoriality between males and females or among males. The maximum observed distance that a single individual traveled and the observed range described, 7.5 km and 15 [km.sup.2], are noteworthy and the first such records in Chaco or Chiquitano dry forests. If an individual may move 7.5 km as recorded, it is almost certain that its home range will overlap with those of other individuals, given the density estimates derived from systematic surveys of about 5-6 individuals per 100 [km.sup.2] in dry forests where they are not hunted. However, the small number of observations permits only tentative conclusions regarding giant armadillo ecology that require confirmation using alternative methods such as radio-telemetry.

Conservation status of giant armadillos in the dry forests of Santa Cruz

Priodontes maximus is known to occur in most of the protected areas from the humid lowlands and lower Andean slopes of Bolivia (Tarifa 1996). More recent hunting records and observations of animal sign suggest that it is still present in other natural areas of the Bolivian Amazon (e.g. Rumiz and Herrera 2000; Rumiz et al. 2001; Wallace and Painter in press). At the same time, local reports indicate that it is disappearing due to hunting and habitat conversion.

By confirming the presence of Priodontes populations in the dry forest landscapes of southern Santa Cruz, the known extension of protected habitat for this species increases considerably. Within the vast Kaa-Iya del Gran Chaco National Park, the Chiquitano transitional forest (as represented at the Tucavaca and Ravelo sites) covers approximately 11,500 [km.sup.2]. In addition, the Chaco transitional landscape (not sampled within the Park, but similar to that of San Miguelito) represents about 9,100 [km.sup.2] of protected habitat. In comparison, Priodontes reports from the Argentine Chaco dry forest are limited to relatively small protected areas (86-1142 [km.sup.2]) that do not offer sufficient protection in the long term (Porini 2001). Though reported from the Brazilian Cerrado (Silveira et al. 1999), its conservation status there is unknown.

Three other newly established protected areas in southern Santa Cruz (ANMI [Integrated Management Area] San Matias, AMNI Otuquis, and Reserva Municipal Valle de Tucavaca, Figure 1) would appear to protect giant armadillos according to observed field signs or unpublished reports of Priodontes (Museo de Historia Natural NKM mammal database). Although hunting and other human activities occur around and sometimes within these protected areas (Arispe and Rumiz 2002), the dry forest landscapes of Santa Cruz are likely to prove a unique stronghold for the long term survival of the species. We will continue to evaluate the conservation status of giant armadillos across additional sites in the protected areas of Santa Cruz and to monitor populations and individuals identified to date.

Table 1. Camera trapping effort and records of Priodontes maximus
at four dry forest sites in Santa Cruz Department, Bolivia.

Site                Trap        Area       Captures   Individuals
                   nights   ([km.sup.2])

Cerro I             2280         49            0           0
Cerro II            1680         49            0           0
Tucavaca Pilot      2520         50           10           8
Tucavaca I          1920        130           10           6
Tucavaca II         1560         60            7           4
Tucavaca Burrows    654          20            1           1
Tucavaca Other      270          8             1           1
Ravelo Pilot        1248         40            0           0
Ravelo I            2160        102            1           1
Ravelo II           1320        101            0           0
San Miguelito       1695         24            3           2
TOTAL              17037                      33          22

Site               Capt/ 1000   * Ind/ 100   Months
                      t-n       [km.sup.2]

Cerro I                0,00        0,00        2
Cerro II               0,00        0,00        2
Tucavaca Pilot         3,97       16,00        8
Tucavaca I             5,21        4,61        2
Tucavaca II          - 4,49        6,67        2
Tucavaca Burrows       1,53        5,00        4
Tucavaca Other         3,70       12,50        1
Ravelo Pilot           0,00        0,00        8
Ravelo I               0,46        0,98        2
Ravelo II              0,00        0,00        2
San Miguelito          1,77        8,33        2
TOTAL

Note: * Density estimates are crude, based on individuals
observed and survey area enclosed by camera traps.

Figure 2. Activity patterns from observations at all three
sites (Tucavaca = 26, San Miguelito = 3, Ravelo = 1).

Priodontes maximus (N=30)

00:00-02:00   9
02:00-04:00   8
04:00-06:00   7
06:00-08:00   1
08:00-10:00
10:00-12:00
12:00-14:00
14:00-16:00
16:00-18:00
18:00-20:00
20:00-22:00
22:00-00:00   5

Note: Table made from bar graph.

Acknowledgements

This publication is based on camera trap surveys conducted by Leonardo Maffei (Tucavaca and Cerro Cortado), Erika Cuellar (Ravelo) and Rosario Arispe (San Miguelito). The research was possible thanks in part to the support of the Agency for International Development (USAID/Bolivia Cooperative Agreement No. 511-A-00-01-00005). The opinions expressed here represent the authors and do not necessarily reflect the criteria of USAID. We would like to thank the Wildlife Conservation Society and Jaguar Cars for financing this research, as well as Ron Larsen for hosting the work at San Miguelito. We also received institutional support from our local partners (Capitania de Alto y Bajo Isoso, Museo de Historia Natural Noel Kempff Mercado) and the Bolivian authorities (Direccion General de Biodiversidad, Servicio Nacional de Areas Protegidas). We thank H. Azurduy for helping to identify individuals and all the field assistants for their demanding labor.

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Silver, S.C., L.E.T. Ostro, L.K. Marsh, L. Maffei, A.J. Noss, and M. Kelly. In press. The use of camera traps for estimating jaguar (Panthera onca) abundance and density using capture/recapture analysis. Oryx.

Tarifa, T. 1996. Mamiferos. pp 165-264 in Ergueta, P. and C. de Morales, eds. Libro rojo de los vertebrados de Bolivia. CDC. La Paz. 347 pp.

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Andrew J. Noss,

WCS-Bolivia, Casilla 6272, Santa Cruz, Bolivia

[e-mail]

Romoaldo Pena

WCS-Bolivia, Casilla 6272, Santa Cruz, Bolivia

Damian I. Rumiz

WCS-Bolivia, Casilla 6272, Santa Cruz, Bolivia

and

Museo Noel Kempff

Mercado, Casilla 2489, Santa Cruz, Bolivia

[e-mail]