Bear Tracking
Bear tracking using radio
telemetry in the
Andes mountains is difficult due to the dense cloud forests and rough
terrain. Our bear tracking volunteers and field technicians
work very hard to collect valuable data about the bears' movements,
from radio telemetry data, bear tracks and occasionally bear sightings.
With this information, we are able to understand more about
the space that Andean bears need to survive.
To track wild Andean
bears we
must first capture them and fit them with radio collars. We
use a non-impact trapping system to minimise the stress caused
to the bear. We have several 'Iznachi' traps
(designed by
Armando Castellanos), baited with cow feet, along
the paths that the bears use, and sometimes in cornfields that bears
enter in search of food. A
radio collar with a
motion sensor, which has been placed on the cage, is activated when the
sliding door of the cage closes. The presence of a signal emitted by
the device informs us if an animal has entered the trap. The sensor is
listened to every hour in the daytime by volunteers on "bear
watch".
When we receive an
active signal from a cage we hike to the cage as
quickly
as possible. We try to have the bear trapped in the cage for as little
time as possible in order to minimize the stress experienced.
We tranquillise the bear, take measurements and
genetic samples before fitting it with a radio collar. The bear is then
moved away from the cage and left to wake in its own time.
The capture, immobilization and collection of samples are managed and
supervised by a veterinary doctor with extensive
experience in the handling of wildlife, who is available in
the
event of any emergency.
Capturing
bears is a slow and difficult process and we are constantly looking for
ways to improve our trapping systems. In the future we hope to use dogs
to track bears by scent and will report on the results here.
In other countries, specially trained Karelian bear dogs are
used in human-bear conflict management and in 2010 we experimented with
using a trained bear dog here - many thanks to Lori Homstol and Sisko.
The results were encouraging and we hope to use this technique
in the future.
The radio-collared bears
are tracked by listening for signals from their collars.
By
means of triangulation, the bear's location can be
accurately determined using three bearings from known points. We track
the locations of
each bear by taking bearings from designated stations, which have been
mapped by GPS. Using mapping software, it is possible to
triangulate to
determine the location of the animal. We can tell the specific
types of habitats used by the bears, as well as those not chosen, by
comparing this data with a satellite image of the area. We
can also
measure the Home Range and Core Area of each bear.
Localizations are placed on a 1:25,000 scale map of the
region and digitalized using the data program Arcview 3.1,
using a satellite image of the study area.
Andean bear sightings in
the wild are rare. Occasionally a few volunteers
have had the opportunity to watch bears whilst they are busy raiding
maize fields, but this is not frequent and is a matter of luck rather
than a bear watching tour. Tracking volunteers also search
for bear tracks in the forest, looking out for bear hair and scratch
markings on trees and bear footprints and scat on the forest
floor. There are opportunities
for bear tracking volunteers all year round.
Andean
Bear Conservation Project: Bear Tracking
The Andean Bear Conservation Project tracks the movements of wild
Andean bears fitted with radio collars, and also searches for bear
tracks, scratch markings and footprints. The bear tracking
data provides information about the space and habitat the bears need to
survive.
