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Jaguar Density in Fireburn, Belize
Report for Wildlife Conservation Society and Belize Forest Department
Carolyn M. Miller, WCS
May 2006
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Introduction
Habitats throughout Mesoamerica have become increasingly fragmented in recent years. The
issue of connectivity throughout Mesoamerica has been at the center of many corridor and
conservation efforts over the past decade or more. Northern Belize, with well established
communities and extensive habitat conversion for sugar cane cultivation and other agriculture,
still has many pockets of forested habitats to the northeast, not yet subjected to fragmentation,
that is the focus of ongoing conservation efforts.
Biological corridors have been a reoccurring conservation theme in Mesoamerica dating back to
the early 1990's with the “Paseo Pantera” (Path of the Panther), conceived by Archie Carr III.
The concept was to link green areas throughout Central America so that conceivably, a "panther"
(i.e., Puma concolor) or at least its genetic progeny, could walk the length of the isthmus and
beyond. Tracts of forest within northeastern Belize leading into Mexico's Yucatan Peninsula
have been designated part of Belize's Northern Biological Corridor, one of seven national priority
areas under the National Protected Areas Policy and System Plan (NPAPSP; Meerman and
Wilson, 2005).
Highlighted as an important link is the north east corridor joining Shipstern Nature Reserve to
Freshwater Creek Forest Reserve, via the Fireburn and Balam Na private reserves, 735 ha and
166 ha respectively (Fig. 1). These two forested areas (managed by the Wildtracks NGO based
in nearby Sarteneja Village) may be considered "core areas" within the corridor, historically
recognized for their value as refuges during times of heavier hunting pressure (Walker and
Walker, in lit.). A question has been whether this corridor area, allows adequate movement of
jaguars (Panthera onca). For the purposes of this report, the area will be referred to as
"Fireburn" although it should be understood that it includes the Balam Na and northern Balam
Jungle areas as well.
After the successful camera-trapping for jaguar density study in Gallon Jug Estate (GJE) during
March-June 2005 (see report to WCS JCP), those same camera trap units were transferred to
NE Belize, making maximum practical and economic use of the improved TrailMaster unit
battery life (up to one year) and film left over from the GJE study. Anna Swift, a Wildtracks
volunteer, assisted during the GJE survey, becoming fully trained in model design and
camera-trapping through her apprenticeship. She transferred these skills and training to the
Fireburn Jaguar Project, under the auspices of Wildtracks, carrying out fieldwork for the study at
the Wildtracks administered Fireburn Reserve area, with the assistance of another Wildtracks
volunteer, Allan Ramsay. The presence of a natural corridor linking two forested nodes across
an open mangrove savanna coastal plain was considered a promising area within the NE corridor
to carry out a camera trapping study for density study at a minimal cost.
C. M. Miller
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When considering the issue of linkage throughout the country of Belize, connectivity into
Mexico's Yucatan and habitat suitability for jaguars in NE Belize is of major concern. Thus, the
principle goal of this study was to estimate jaguar density, using WCS-developed protocols, in an
important conservation target area of Belize.
Figure 1. Fireburn within context of the Northeast Corridor (Map: Walker and Walker,
Wildtracks, 2006)
C. M. Miller
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Study Area
The Fireburn study area lies 5-15 km from the Caribbean coastline in NE Belize. Mexico's
Yucatan Peninsula lies across Chetumal Bay approximately 28 km away (Fig. 1). Annual rainfall
in northern Belize averages1524 mm.
The area in and around the study site can be considered multiple use with conservation areas such
as the Shipstern Nature Reserve (managed by the Swiss-based International Tropical
Conservation Foundation) to the north, the Fireburn and Balam Na Reserves (managed by
Wildtracks) and the Maya site, Kakantulix, currently being established as an archaeological
reserve (121 ha, to be managed by the Institute of Archaeology) as the central focus of the
corridor, and the Freshwater Creek Forest Reserve to the southwest (Fig. 1). The Mennonite
community Little Belize, to the west, practices intensive agriculture. Finally, much of the Balam
Jungle Estate property is undergoing selective logging and speculation development.
Lying within the project area, the Northeast Corridor has been highlighted as one of three
national priorities under the Mesoamerican Biological Corridor Program, and one of seven
priorities under the NPAPSP (Meerman and Wilson, 2005), providing protection for key species
by linking the forest node in the Fireburn area (including Shipstern Nature Reserve, Fireburn
Reserve, Kakuntulix Archaeological Site, and the provisional Government corridor area) with
that of the Freshwater Creek Forest Reserve, through the Balam Jungle Estate. This project area
contains one of the few natural physical forest corridors -- a narrow strip of forested land that
allows the movement of wildlife between the two forest nodes -- Shipstern/Fireburn and
Freshwater Creek, preventing genetic isolation. This also provided an excellent opportunity for
documenting the movement of species along forest corridors, and their use of the corridor itself
(Walker and Walker, in lit.).
Consisting of a rich mosaic of different ecosystems, where species with Yucatan affinities mix
with those more often associated with the Peten and more southerly regions, the Fireburn area
has a particularly species-rich biodiversity. This is further enhanced by the isolated nature of the
area. With only the Fireburn Community (population 37) within its boundaries, hunting pressure
has been much less severe than in other parts of Belize, and many game species such as Great
Curassow and white-lipped peccary are abundant (Walker and Walker, pers. obs).
Thirteen habitat types (UNESCO classification scheme; Meerman and Sabido, 2004) were
present in the study area1 which comprised 132 km2 . Although a "more compact polygon" might
have been more desirable for the study, skirting inundated areas dictated the study design (Fig.2)
1
Walker and Walker (in lit.) note that there are some errors for the overall study area
classification that need correction (e.g., an area of high forest is designated as agriculture).
C. M. Miller
Figure 2. Camera traps and Fireburn habitats (Map: Bruce W. Miller, WCS)
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Methods
A total of 16 paired camera-trap stations were operated across the Fireburn reserve. The study
design was developed to take advantage of dry areas and avoid inundated areas (e.g.,
“permanently waterlogged freshwater mangrove scrubs,”see Fig. 2). Roads and trails were used
throughout the study area, skirting areas of inundation. Of the 16 trap stations, 10 were situated
along trails that were "old" (i.e., overgrown in places) and appeared seldom used by people,
while the other 6 locations were actively used for logging and/or hunting access by the
neighboring communities (see Appendix I for notes on specific locations). The cameras were
placed in opposition to each other, approximately 45-cm high, not more than 1-m off the trail.
TrailMasterTM active 1550 units were used with Canon 35 mm underwater marine cameras.
Established camera-trapping protocols (Karanth, 1995; Karanth and Nichols, 1998; Karanth et
al., 2004) originally developed to monitor tiger populations and adopted for jaguar surveys
(Silver, 2004) were followed. Each camera trap station was placed in an area that appeared
promising for jaguar activity separated by a minimum 2 km and not more than 3 km from
adjacent stations. This distance was chosen based both on accessibility in otherwise inundated
areas using established trails and on previous camera-trap density studies where 9 km2 was
considered the approximate territory size of a female jaguar (Rabinowitz, 1991).
All camera-stations operated simultaneously for a minimum period of 63 days (16 June - 17
August 2005) using Kodak 400 ASA print film. The cameras were set to operate 24 hours/day
and trigger at 3-minute intervals when activity occurred and a date/time stamp was imprinted on
the film. Camera-stations were checked every 7-10 days in order to change film or batteries as
necessary by volunteers Swift and Ramsay. Subsequent results were scanned and digitally
adjusted if necessary, to improve the ability to compare pelage patterns by the author. The
resulting photos were classified based on the unique pelage patterns of jaguars also by the author.
The jaguar captures (including those individuals photographed multiple times) were analyzed
using the software program CAPTURE (Otis et al., 1978; White et al., 1982; Rexstad &
Burnham, 1991).
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Results
In addition to the target species, the jaguar, photo-captured species at the study site included:
Great Curassow (Crax rubra), opossum (Didelphis sp.), paca (Agouti paca), brocket deer (Mazama
americana), gray fox (Urocyon cinereoargenteus), Ocelot (Leopardus pardalis), puma (Puma
concolor), and Baird's tapir (Tapirus bairdii). A few incidents of vehicle traffic were also
documented. With the units set at 45-cm high, judged optimal for jaguars, it seems likely that
many smaller species escaped detection as they passed below the infra-red beam.
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CAPTURE Program Analysis
As in previous studies, the CAPTURE program was used to estimate jaguar population density
for the Fireburn site. CAPTURE identified the jacknife estimator and heterogeneity M(h) as the
most appropriate in order to estimate population density. This corresponds with
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recommendations of Karanth and Nichols (1998) that suggest that M(h) most accurately takes
into account the variable capture potential for individuals based on age, activity patterns and the
like. Each day was considered a separate sampling occasion (n=63). The standard error was
calculated from the variance estimated and estimated areas surveyed (Karanth and Nichols,
1998).
Table 1 shows the abundance estimate using the M(h) heterogeneity model (following Karanth
and Nichols,1998; Maffei et al,. 2004). The heterogeneity model is thought to more accurately
take into account the differing probabilities of capture for individual animals based on such
factors as age, dominance and the like. The buffers were derived from the mean maximum
distance traveled at each survey location, the survey area and estimated density. Per Karanth and
Nichols (1998), the SE is calculated from the variances in the abundance estimate and the
sampled areas estimate.
Table 1. Estimate of Fireburn jaguar density (individuals/100 km2 ) in comparison with GJE
Site
Fireburn
Captures
per100 nts
Capture
probability
Abundance a
1.2
0.0227
7
2.60
132
5.3
±1.76
4.74
0.0484
15
2.53
170
8.82
±2.27
2.1
0.0283
22
3.45
195
11.28
±2.66
Buffer
(km)
Area
(km2 )
Density
SE
GJE 2005
GJE 2004
a
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estimated M(h) model (CAPTURE), assumes heterogeneity of capture probability
Discussion
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Density Estimate
Density estimates for two study sites in Belize (Cockscomb Basin Wildlife Sanctuary, Chiquibul
National Park) and three in Bolivia (Tucavaca, Cerro Cortado and Madidi) based on the
CAPTURE analysis varied from 2.8-8.8/100 km2, and the effective area sampled ranged from
107 km2 to 458 km2 (Silver et al., 2004). GJE estimated jaguar density was 8.8/100 km2 over an
area of 170 km2 and 11.3/100 km2 over an area of 195 km2 in 2004 and 2005 respectively (Miller,
2005a; Miller, 2005b). Fireburn compared favorably with these sites with an estimated jaguar
density of 5.3/100 km2 over 132 km2 . Five of 16 Fireburn camera trap stations, roughly one third,
photo-captured jaguars compared to approximately 50% that captured jaguars in GJE.
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Individual Jaguars
Three male jaguars were identified as well
as two of undetermined gender. All animals
appeared to be in healthy condition. Station
7 (Fig. 3) had the most jaguar activity with 3
individuals comprising 5 captures during the
study. There were also 4 puma captures
although it was impossible to determine
whether this was due to single or multiple
individuals. It is difficult to hazard a guess
as to why Station 7 was so productive other
than it was placed in a narrow corridor with
inundated areas on either side perhaps
channeling cat traffic (Fig. 2). All jaguar
captures occurred in one main vegetation
type: tropical evergreen seasonal broadleaf
lowland swamp forest, either the
“high”variant or the “Yucatan” variant.
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Figure 3. Male 2 appeared in 3 locations
including Station 7
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Conclusions
The density estimate for Fireburn jaguars was 5.3/100 km2 , approximately half that of GJE
averaged over the 2004-2005 studies. Given that GJE appears to be “nearly ideal” habitat for
jaguars (i.e., protected against hunting, healthy prey base, mature tropical moist broadleaf forest,
intact hydrology), the density estimate for Fireburn can be considered very good. With pressures
from adjacent human communities as well as areas of inundation (where habitat, at least
seasonally, may be less available), it appears that jaguar density is on par with other areas
surveyed to date.
Thus, the Fireburn "core areas" should be considered important to corridor linkage efforts with
proof that jaguars use the area. Further, it appears that a healthy genetic flow is possible at this
time for jaguars. This large charismatic felid is considered an “umbrella” species where, if habitat
is suitable, then it is assumed that it is likewise suitable for many other species. Continued
changes to the habitat, increased human use and/or severance of the natural forested corridor may
adversely affect jaguars, and other species, in the future.
Future studies might focus on other sites within the Northeast Corridor to see how density
estimates compare with Fireburn. A follow up to our 1995 survey in Shipstern Nature Reserve to
the north, would be useful since this area has been protected for approximately 20 years. In
1995, we estimated 5 jaguars for this reserve after a two week survey searching for tracks and
sign and using camera-traps (no jaguar photos were taken; Miller et al., 1995). Likewise, a
follow up survey at Freshwater Creek Forest Reserve would be useful. In 1995, numerous tracks
and sign as well as an occasional sighting were documented for this Forest Reserve (Miller and
Miller, 1995) which was, at the time, undergoing illicit logging and hunting – activities that
continue there to date (Walker, P., pers. com.).
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Given that development and other human activities show no signs of abating, are there zones of
jaguar/human conflict whether it be due to hunting (of jaguar and prey species) and predation on
livestock and domestic animals? A survey of prey base to support jaguars would be valuable.
An estimate of hunting pressure on both jaguars and prey species would be useful to evaluate
whether jaguars will persist in the long term in northeastern Belize.
A reoccurring conservation theme in Mesoamerica is corridors: feasibility, location,
development, protection. When considering a healthy genetic flow along Belize's Northeast
Corridor, the Fireburn area appears to be very important for jaguars both in terms of maintaining
a significant density of individuals and in providing connectivity between sub-populations that
might otherwise become isolated.
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Acknowledgments
The Wildlife Conservation Society provided funding for this project. The Belize Forest
Department issued the necessary research permit. Computer hardware was provided by the Terra
Foundation.
Paul and Zoe Walker, Wildtracks, were integral to the study and provided infrastructure and
logistics support as well as expertise. Based on their experience and familiarity with the study
area, their comments and critiques substantially improved this report. Anna Swift and Allan
Ramsay, with assistance from Normando Mora, all with Wildtracks, carried out field work,
bicycling to the sites, braving voracious mosquitos and ferocious heat. Nathan Funk granted
permission to conduct part of the study within the Balam Jungle Estate property, and Juan
Aldana of Balam Jungle Estate assisted with logistical support.
Special thanks to Anna Swift for her concerted efforts at Fireburn and in Gallon Jug. Bruce
Miller's assistance at every level of the study was invaluable.
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Literature
Karanth, K. Ullas. 1995. Estimating tiger Panthera tigris populations from camera-trap data
using capture-recapture models. Biological Conservation. 713 33-338.
Karanth, K. Ullas and J. D. Nichols. 1998. Estimation of tiger densities in India using
photographic captures and recaptures. Ecology. 79(8)2852-2862.
Karanth, K. Ullas, Raghunandan, S. Chundawat, Nichols, James D., Kumar, N. Samba. 2004.
Estimation of tiger densities in the tropical dry forests of Panna, Central India, using
photographic capture-recapture sampling. Animal Conservation. 7:285-290.
Maffei, L., Cu'ellar, E., and A. Noss. 2004. One thousand jaguars (Panthera onca) in Bolivia's
Chaco? Camera trapping in the Kaa-Iya National Park. Journal of the Zoological Society of
London. 262 295–304.
Meerman, J. and W. Sabido. 2004. Central American Ecosystems (updated from 2001): Belize.
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Programme for Belize, Belize City. 2 volumes 50 + 88 pp.
Meerman, J. C. Wilson J. R., Eds. 2005. The Belize National Protected Areas System Plan.
Belmopan, Belize; 61 pp. CD.
Miller, C. M. 2005. Jaguar Density in La Selva Maya. Technical report for WCS and Belize
Forest Department. 13 pp.
Miller, C. M. 2005. Jaguar Density in Gallon Jug Estate, Belize. Technical report for WCS and
Belize Forest Department. 24 pp.
Miller, B. W. and Miller, C. M. 1995. Avian Surveys: Freshwater Creek Forest reserve 1-10
March, 1994. In Reichelt, Brit and Philcox, Cengiz. A Faunal Survey of Freshwater Creek Forest
Reserve. Belmopan, Forest Planning and Management Project. Occasional series.
Miller, B.W., Miller, C. M., and Quigley, H. B. 1995. Shipstern Nature Reserve Mammal
Survey. Gallon Jug, Belize, Wildlife Conservation Society. A Technical Paper of the Wildlife
Conservation Society, Belize Tropical Forest and Planning Project.
Otis, D.; K. P. Burnham; G. C. White, and D. R. Anderson. 1978. Statistical inference from
capture data on closed animal populations. The Wildlife Society, #62; 621-135.
Rabinowitz, A. R. 1991. Jaguar. New York.. Anchor Books
Rexstad, E. and K. Burnham. 1992 Apr29. User's guide for Interactive Program CAPTURE. Ft.
Collins, Colorado Colorado State University
Silver, S. C. 2004. Assessing jaguar abundance using remotely triggered cameras.
http://savethejaguar.com/media/file/Camera%20trap%20Protocol.FINAL.12.21.pdf
Silver, S. C.; Ostro, L. E. T.; Marsh, L.; Maffei, L; Noss, A. J.; Kelly, M.; Wallace, R. B.;
Gomez, H., and G. Ayala. 2004. The use of camera traps for estimating jaguar Panthera onca
abundance and density using capture/recapture analysis. Oryx 38(2):148-154.
White, G. C.; Anderson, D. R.; Burnham, K. P., and D. L. Otis. 1982. Capture-recapture and
removal methods for sampling closed populations. Los Alamos National Laboratory Publication
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Appendix I. Notes on Camera Sites (Anna Swift, Wildtracks)
CT-1: Barrigas' Track, 20 m within village farmland boundary line. Mixed cohune, medium
forest, dense understorey. The Barrigas’ track is used for hunting and access into
forest for logging by the local Fireburn Community.
CT-2: Situated on the southern trail, which extends south of the southern Fireburn boundary.
Tall forest, with open understorey. The site is on an old logging trail that has been
used recently for access. Fairly overgrown in places along the trail.
CT-3: The site is just south of the turning to Fireburn pond. Mixed cohune, medium forest, with
dense understorey. Trail kept open for access purposes.
CT-4: Situated east the eastern boundary of Kakantulix Archaeological reserve. Dense Cohune
forest leading into tall forest. Logged area of forest, trail is regularly used for
logging access via tractor.
CT-5: South of Kakantulix. West of Corridor road. Trail heads down towards savannah. Tall
forest with dense understorey. Trail used as an access route for logging and
extraction and is situated within government land.
CT-6: Situated on an old logging trail, west of Corridor road, within Balam Jungle estate. Tall
forest with dense understorey. Trail is slightly overgrown in places and meets
transitional bajo.
CT-7: Situated along narrow section of corridor, on the corridor road, in Balam Jungle Estate.
Low dry dense forest, bordering onto bajo backing onto savannah.
CT-8: Southern end of narrow corridor stretch, on corridor road. In Balam Jungle Estate. Bajo,
low forest bordering onto savannah, vegetation includes hulube and palmetto. 2
water holes 200 m north of site. Area is seasonally inundated.
CT-9: Site is situated at the bottom end of the narrow part of the corridor on Balam Jungle
Estate land. Medium-tall forest with dense understorey, savannah on either side of
forest.
CT-10: Southern part of Corridor road, Balam Jungle Estate. Tall forest with dense understorey.
Savannah situated about 1km south of site.
CT-11: Southern part of corridor road, Balam Jungle Estate. Medium-tall forest with very dense
understorey.
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CT-12: On bulldozed road (Balam Jungle Access Road), 400 m south of corridor track turn-off.
Medium-tall forest with very dense understorey. Pond found south of site, situated
in savannah. Road has a lot of traffic, accessing land further south.
CT-13: East, off Balam Jungle Access road. Southeast of Balam Na. Medium-tall forest, less
dense understorey. Very old logging trail, overgrown in most places.
CT-14: Old logging trail within Balam Na. Tall forest with more open understorey. 1 km east of
savannah
CT-15: Old logging trail, in northwest corner of Balam Jungle Estate. Tall forest with less dense
understorey. Site is located on a fork in the trail, one of which heads off into
Mennonite land. Frequently used by hunters.
CT-16: Along old logging trail, within Balam Jungle Estate. Medium-tall forest with dense
understorey. Old access road, heading into Mennonite land. Frequently used by
hunters.