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You will hear part of a presentation about a
biologist who has studied an animal called the
Arctic hare.
Good evening. My presentation tonight is about the
work of Dr David Gray. Dr Gray is a biologist and
writer whose love of the Arctic led him to study birds
and mammals in Canada’s far north over many
decades.
Dr Gray’s work mainly focused on the behaviour of
the Arctic hare, a member of the rabbit family, as
well as on Arctic wolves and other species found in
the far north of Canada. David planned and carried
out a research project on the behaviour of Arctic
hares, making seven research trips to the Nunavut
area of northern Canada over a period of twenty
years. Dr Gray’s research was what’s termed an
observational study, and the photographs and video
footage that document the research are stored in
the archives of the Canadian Museum of Nature.
The study area chosen for the project was a seven-
kilometre stretch of the Sverdrup Pass, which is an
80-kilometre-long pass that runs across northern
Ellesmere Island in Nunavut. The study area is
about 600 metres above sea level, and is bounded
on the north side by mountains rising to 1,500
metres above sea level, and to the south by
mountains and a valley glacier leading up to a major
icecap rising to more than 2,000 metres. Within the
study area of the pass, the sandy flats in mid-valley
are scattered with clumps of Arctic willow trees and
other types of vegetation.
The animals are white in colour in winter, providing
the perfect camouflage in snowy conditions. So how
does a researcher go about finding Arctic hares in
this type of landscape? Arctic hares can be tracked
by following fresh tracks in snow. Even on hard
snow drifts, it’s usually possible to make out the toe
marks of an Arctic hare, even when the shape of
the whole foot can’t be discerned. But finding the
animals themselves is basically a visual search,
which is fairly easy in the High Arctic because the
hares don’t have much vegetation to hide in. The
presence or lack of droppings is a good indication of
whether hares can be expected in an area. Such
evidence is often found around rocks, which are a
better starting place when looking for hares than
wooded areas or open meadowland.
Dr Gray’s research team also trapped live Arctic
hares before marking them and releasing them.
Wire-mesh traps were found to be effective for this
purpose. As bait to lure the hares in, dried apples
were placed inside. Both single-door and double-
door traps were used. Once inside the trap, each
hare was weighed, measured, colour-marked with
picric acid, and tagged with a small coloured and
numbered ear tag. Using different combinations of
coloured tags in one or both ears allowed at least
twenty hares to be identified individually, even when
tag numbers couldn’t be read. When using a
telescope, some hares could be identified from up
to two kilometres away in good light conditions, and
the tag number could be read from a 175 metres
away.
The standard hare-watching equipment is a
binocular telescope mounted on a tripod. The tripod
makes watching for long periods possible and frees
the hands for note-taking or photography.
Researchers worked in shifts and watched Arctic
hares 24 hours a day, but usually concentrated on
the early-morning and mid-afternoon shifts which
corresponded to active feeding cycles. During the
breeding season, however, more effort was spent
on the midnight shift because late evening and early
morning are prime times for breeding activity. After
the young were born, summer observation hours
were determined by the nursing schedule of the
mother hares.
So, before I go on to …
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