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Volcanoes and Coyotes, Turrialba Volcano Costa Rica
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From: E. Duarte <volcano@xxxxxxxxx>
Visit to Turrialba Volcano reveals expansion of area affected by
gases.
(Dead forest may force coyotes to migrate to residential areas)
Field report, August 30, 2006.
During a visit to Turrialba Volcano (august 30, 2006), accelerated impact on
vegetation in and around the summit, was documented.
This volcano has shown a variety of activity peaks during the last 10 years,
mainly seismic swarms and vigorous gas activity. Nonetheless one year ago
(June 2005) one of the greater events of fumarólic expansion was reported. Such
expansion was accompanied by gas increment, in quantity and composition,
implying higher levels of exposure of vegetation to acid deposition (dry and
wet).
Bushy species and minor plants, that had managed to survive in the open
summit area (inner walls), now look completely burned. The tree belt, reported
as partially burned last year (located on the NW outer flanks) now shows a
significant percentage of dead birch (Alnus acuminata). Such belt (200m x
900m aprox) includes species taller than 25m and is visible from the lower
inhabited farms where intensification of gas odors has been reported. Most of
the dead trees are rapidly decaying due to the fragile nature of birch wood.
The shape of the burned area correlates with the wind pattern and their
prevailing direction during this season. Changes in that pattern may include,
other areas less affected, in the near future.
Interestingly enough, coyotes were observed at the middle of the day during the
fieldwork ( although their habits are nocturnal). Such observation may imply
that the only forest belt, between the summit and the farms is threatened to
disappear thus forcing the animals to migrate to residential areas. Moreover, the
coyotes` hunt area (in the summit) changed rapidly due to the disappearance of
vegetation where small mammals and birds used to feed.
This is one of the rare examples where forces of nature reduce spaces between
humans and wildlife. Hence multi-institutional efforts are require to minimize
impact.
Note: More details and photos are available at www.ovsicori.una.ac.cr
Text: E. Duarte and E. Fernández. OVSICORI-UNA. Costa Rica.
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