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Methods
With the assistance of Earthwatch volunteers, the lead PI,
Luke Dollar, conducted his first field season at the Ampijoroa
Research Station in 1999 to investigate the research site
and lay the groundwork for this ongoing project. The PI led
a trapping and radiotelemetry study in the Lac Tsimaloto region
of Ankarafantsika (22 km east of the Ampijoroa Research Station)
the year before, in 1998. At the Lac Tsimaloto site, six different
Cryptoprocta were trapped in 12 trapping events during
400 trap-days. More than 300 hours of radiotelemetry data
were also collected during this 3.5 week survey. While the
biomass of predators found in the Lac Tsimaloto (1998 and
2001 surveys) and Ampijoroa (1999-present) regions of Ankarafantsika
National Park was relatively constant, the composition of
Ampijoroa’s top trophic level was completely unexpected.
In 1999, we made an unexpected discovery. Wild cats, large
competitive felids (possibly the African Wild Cat or a Malagasy
variant), are present in Ampijoroa’s savannahs and transition
forests. This elucidates an alarming problem faced by endangered
endemic carnivores worldwide. While the cats are relatively
prevalent in the open and scrubby natural spaces found on
Ampijoroa’s topography, they do not enter or use resources
from deep within Ampijoroa’s woodlands, where the fossa
retains a competitive predatory advantage. Although the fossa
is still the only predator capable of preying on the largest
of prey species – Ampijoroa’s larger primates
– the presence of the wild cats leads to a notable difference
in the density and ranging of Cryptoprocta. At Ampijoroa,
fossa occur at lower density than in the nearby Tsimaloto
region. In addition, their home ranges are larger. Although
the diet of fossa in the presence of this new-found felid
competitor has not yet been fully examined, preliminary results
indicate that Cryptoprocta specialize more heavily on prey
species that the wildcats are incapable of taking than they
would in habitats free from competition. We have collected
more than 1000 scat samples over the last three years. Analysis
is complete on 800 of these as of September, 2001.
In 2001, we have noted a significant increase in density
of Cryptoprocta nomadically passing through our study
areas. While we would like to believe that this increased
trap success belies an increased level of conservation for
fossa in the Ampijoroa region, other factors are also likely
affecting this trend. Significant habitat disturbance in the
east end of Ankarafantsika (as identified by satellite analysis
and ground truthing surveys) has caused an upsurgence of pressure
leading to an apparent westward migration into the remaining,
less-disturbed habitats within the Park.
Primary Objectives and Their Methods
1) Conduct trapping surveys to further locate and identify
the carnivore populations and trends in the Ampijoroa Research
Station area of Ankarafantsika National Park, Madagascar,
collect anatomical data on each species of carnivore at this
site, and to collect carnivore scat samples for analysis of
diet composition/contents; and
2) Establish baseline indices or indicative measures of relative
abundance of Cryptoprocta ferox and additional carnivore populations
in the dry, deciduous forests of Ankarafantsika;
Trapping surveys
Initially, large grids and transects were mapped onto several
portions of the study area. Large Hav-A-Hart and Tomahawk
live-capture cage traps are placed at regular intervals on
the transects and grids, for a total of more than 40 active
traps. As there is no means of travel within the research
area other than by foot, our trap-line size (up to 25 km in
a single hike) is the largest that is physically feasible
to practically pursue the goals of this study. Considering
the relatively large home range of Cryptoprocta (Dollar, 1997;
Hawkins, 1998), a much larger area would be required to attain
actual abundance measures (Wilson et al, 1996). Therefore,
attaining indices of relative abundance (as in Caughley, 1977,
among others) is a more realistic focus for this study (objectives
1 and 2). The location of the trap grids remains constant
from survey period to survey period to lower the likelihood
of bias in achieving objective number 2. In addition to following
our specific mark-recapture protocol for multiple 10 day trapping
sessions (in adherence to previous studies), other traps are
often opportunistically moved to additional, remote parts
of the surrounding forests so as to potentially increase the
sample size of study animals.
Ten day trap surveys are conducted by each team of Earthwatch
volunteers. This affords a total of at least 400 traps/day/team
session at the research site. Traps are checked twice daily
while active trapping is in effect. Two trap-checking groups
“split up” to each check separate trap lines.
During each check of the traps, a walking census of all animals
encountered is also conducted, providing baseline ecological
monitoring data for analysis of long-term biodiversity trends
in Ankarafantsika. All fossa scats (>1000 to date) are
collected during grid checks (objective 1). Fresh and incompletely
dessicated fossa scats are easily differentiated from wildcat
scats by their characteristic smell. Additional distinguishing
features include the shape and deposition/distribution of
the scats themselves. In addition, fossa scats have a characteristic
long tail that is not seen in the wildcat samples we have
collected to date.
Trap check teams stay in contact with one another, the radiotelemetry
teams, and base camp via the use of hand-held radio. The number
of captures per unit effort provides a baseline measure or
index for assessment of relative abundance of species captured.
This measure is important for the long-term monitoring of
carnivore populations within the research area, helping to
meet objectives 1, 2, 6 and 10 as outlined in section 2.
In addition to the cage-trapping portion of the survey, phototraps
are also used to help evaluate the variety and presence of
carnivores and their prey in Ankarafantsika National Park.
Phototrapping involves a wide-angle, weatherproof photographic
apparatus attached to either an infrared or motion sensor
- or even a pressure pad - which triggers the shutter release
when activated, exposing the animal and time of passage on
film. This type of mechanism can ‘trap’ more than
one animal before reactivation, does not depend upon physical
encounter, investigation, and entry. This procedure involves
much less trauma on part of the animal in question -- an animal
need merely pass by the camera to be ‘trapped,’
after which it continues on its way unaware of its contribution
to the assessment of its environment. This technique has proven
successful for photocapturing terrestrial, arboreal, and avian
fauna and is responsible for the discovery of more than one
previously unidentified species and has also provided incontrovertible
evidence and identification of poachers and illegal tree cutters
in many areas (Wilson et al., 1996).
While photo-traps are not used as replacements for cage traps,
some cameras are placed in proximity to cage traps to facilitate
an evaluation of the number of trap visits by study animals
relative to actual capture events at those traps. Phototraps
placed in additional areas of the research site help to confirm
or refute that all possible carnivore species are sampled
at Ampijoroa by affording a non-invasive capture technique.
After the cage trapping portion of each field season is complete,
camera traps are placed along the grid system to provide “recaptures”
of the individually marked fossa as well as uncaptured and
immigrant animals. This bait station analysis also provides
us a means of forming an index of relative abundance for fossa
population monitoring (Bookhout, 1996) that does not rely
on an animal entering into an enclosed cage. Nor does it depend
upon the reliability of multiple observers to find and assess
numbers of feces or tracks found on the grid. This camera
technique has been successfully implemented on a number of
North American carnivores including bears (D. Martorello &
M. Pelton, pers comm), marten, fisher, lynx, and wolverine
(Zielinski and Kucera, 1995).
Animal handling, processing, and measurement
Captured Viverricula will be released from the trap
into a handling bag. Drug is administered via intramuscular
injection with the animal still in the handling bag. Captured
Cryptoprocta and Wildcats are tranquilized while still in
the trap using the Pneu-dart drug delivery system. Using the
Pneu-dart system, a trained staff member blowpipes the trapped
larger carnivores using procedures outlined by Glander, et
al. (1992). Anesthesia is delivered via dart in the hindquarters
and only if the animal is facing away from the shooter so
as to reduce the risk of damage resulting from shots in the
face, abdomen, shoulder, or neck.
Once the animal appears to be adequately tranquilized, the
darter and an assistant remove the tranquilized animal from
the trap or handling bag. Anatomical measurements are taken
prior to affixing and activation of the radiocollar device
to captured fossa. Anatomical measurements collected include
weight, total body length, tail length, hind limb length,
hind foot length, hind limb girth, forelimb length, forefoot
length, forelimb girth, chest girth, neck circumference, height
at shoulder, ear length, canine anterior-posterior and lateral
diameter, carnassial molar lengths, and genital measurements.
All anatomical data are collected by the lead PI so as to
avoid bias in interobserver measurement techniques.
The morphometrics selected represent a conglomeration of
anatomical measurements used in several different realms of
mammal ecology. Definitions for most of these measures are
derived from Dayan & Simberloff (1994) and Eason Smith
& Pelton (1996). Body length is measured from the tip
of the nose to the base of the tail. Tail length is measured
from the base of the tail to the tip of the most distal bony
tail segment (tip of the last tailbone). Hind limb and forelimb
length is measured from the medial fold of the limb to the
tip of the longest portion of the foot pad. Hind foot and
forefoot length is measured from the most proximal to the
most distal portion of the foot pad (from the maximum points
on the foot). Forelimb girth is measured around the widest
portion of the brachium. Hind limb girth is measured around
the widest portion of the thigh region. Chest girth is measured
just inferior to the forelimbs. Neck circumference is measured
at its widest point. Collection of this information fulfills
objective 1.
After anatomical measurements, ear-tagging, blood and tissue
collection (for population genetic analysis - objective 9
– and for epidemiological study – objective 13),
and attachment of a unique color-coded radiocollar are complete,
the study animal is returned to the traps at the location
of capture, monitored until free from drug effects, and released.
3) Track captured fossa and wildcats using radiotelemetry
to determine their home ranges and activity patterns;
Activity and ranging assessments using radiotelemetry
There are two main foci in the use of radiotelemetry in this
project. They are: to assess ranging and the pattern of activity
in Cryptoprocta and other carnivores, including wild
cats, in the study area.
Once the first new radiocollars (1 year life span) are attached
and study animals are released each new field season, the
radiotracking portion of this project begins. Subgroups of
volunteers and staff members collect ranging data on study
animals using two-receiver triangulation techniques from recently
constructed, permanent radiotelemetry towers at far ends of
the research area. This technique involves radiotelemetry
teams placing themselves at known, regular monitoring stations/locations
(towers) and simultaneously recording the bearing of a given
radio-signal from that location. Locations for each study
animal are measured twice per day (roughly every 12 hours)
when within range. The previous range of our radiotelemetry
equipment was limited to less than 2 kilometers. With the
completion of 5 m tall radiotelemetry towers (permanent, large
antenna at 7 m), that range is increased by up to an order
of magnitude. Teams coordinate their measurements using hand-held
5-watt (high output) 2-way radios. The locations of and bearings
between the monitoring stations (towers) is known to within
5 m, measured using Global Positioning System (GPS) data collected
when the station locations were originally identified.
As the need for additional monitoring sites presents itself,
they are mapped onto more remote portions of the study area
for future tower placement. Two additional towers are slated
for construction within the research area within the next
six months, for a total of four monitoring stations. The monitoring
stations and all their inter-site proximities are mapped onto
x, y axis, and assigned x, y coordinates. The simultaneous
signal bearings taken at these stations will be used to calculate
an x, y coordinate of the animal’s location at that
time using the program TRIANG (White and Garrott, 1990). Using
the program WILDTRACK, these location coordinates, taken over
time, will be used to calculate movement patterns. Home ranges
will be calculated using the minimal convex polygon method
of home range estimation.
Only two radio towers are used for regular data collection
at present, as only two towers have been constructed. The
project vehicle is opportunistically used as a third triangulation
point. We will be able to more regularly utilize three position
triangulation techniques with the upcoming completion of construction
of additional towers.
In addition, measurements of activity patterns are facilitated
by the use of activity sensors built into the radiocollars.
Volunteers not only note bearing to the study animal from
their monitoring towers, but also note the activity level
given by different activity-level signals emitted by the radiocollar.
This facilitates analyses of daily and seasonal activity patterns
based on “resting,” “locally active,”
and “traveling” measures.
his schedule of radiotelemetry will continue throughout
the ensuing year’s life of each collar, providing information
on seasonal changes in ranging, activity pattern, and habitat
usage and preferences, helping to meet research objectives
3, 6, 8, 10, & 11.
4) Conduct extensive groundtruthing studies for ongoing
remote sensing projects examining trends in fossa habitat;
We examine trends in fossa habitat by using Landsat 5 images
as a baseline for forest cover at the beginning of the last
decade and conducting further analyses on more recent images.
The image or images corresponding to each area of habitat
are rectified to recent, geometrically correct Landsat 7 images
of the same path and row to an error of less than 12 meters
per 100 kilometers. The corrected Landsat 5 baseline image
is then overlaid upon the corresponding newer Landsat 7 image
to create a single twelve-layer file. This file is then classified
using supervised classifications for forest maintained, original
nonforest, forest lost, water, and various image masking characters
such as shadow, cloud, or smoke. Erdas Imagine 8.4 software
is used for image analysis.
The image or images corresponding to each protected area
under scrutiny are reclassified multiple times using ground
truth data. Ground truthing consists of visiting a point of
interest, usually within the protected area, ascertained from
preliminary satellite analysis. At this point, precise location
is confirmed and reconfirmed via GPS positioning. Visual confirmation
of whatever land cover or geological clues may also exist
at that point is also taken into account. Thereafter, detailed
observations of the terrain and cover from N, S, E, and W
venues are collected (and digitally photographed). This information
is then used in additional classification iterations of the
satellite images at hand before the images are then analyzed
for deforestation counts.
5) Continue conservation, development, and capacity building
projects in & around Ankarafantsika.
Generations of scientists have been trained just to observe
and strictly avoid any forms of interference within the systems
where they work. To enclose one’s self into an ivory
tower at the front lines of the global biodiversity crisis
and merely observe is a luxury that we can no longer afford.
The process of conservation occurs at a number of levels,
from global to grassroots. It is at the finest of scales –
in this case, the Ankarafantsika National Park - that the
process of conservation both begins and ends. In Madagascar,
Earthwatch scientists have implemented the first hand conservation
reconnaissance they have gathered. Working at opposite ends
of the island, Dr. Patricia Wright and I have put our impressions
to work for the benefit of the habitats we study. We have
formed ecological monitoring teams of local people who work
first-hand to save “their own backyards.” Both
Ankarafantsika and Ranomafana National Parks will have centers
for conservation, research, and training finished on-site
within the next two years. We are making significant advances
in learning from and preserving our research sites by taking
first-hand knowledge of our respective areas and infusing
the local populations with our same enthusiasm for protecting
Madagascar’s biodiversity, while simultaneously going
face to face with park managers to make our voices heard.
We are not simply gathering data for scientific publication.
We are examining a conservation crisis with scientific scrutiny
and mounting battles to protect Madagascar’s biodiversity.
The presence of our core team, accentuated by the presence
of Earthwatch volunteers facilitates extraordinary conservation
and development initiatives at Ankarafantsika. The following
will discuss applications of our presence from multiple perspectives,
including those of policy and research. The bullet points
and discussion following them are all points of action conducted
by our team and its individual members.
While our research on the fossa indirectly contributes to
conservation and development, it is the impetus for our on-site
presence. This presence facilitates our research and development
initiatives. Year-round data collection leads team members
to be on site year round when tracking animals. Infrastructural
support for our teams – as supplied by local communities
- gives a sustained, viable alternative to traditional environmentally-unsound
practices. Without our research base, this additional work
for the conservation and development of Ankarafantsika would
not be possible.
the project
| research
objectives | application
of results
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