Novel approach to track migration of arctic-breeding avian species
 |
| Versita |
Animals move around the globe in billions, sometimes -- like the
snow bunting -- one of the iconic Arctic-breeding species, covering huge
distances and enduring the most extreme frigid weather conditions. In this
conspicuously white sparrow-sized bird, animal migration epitomizes a stunning
success of biological adaptation -- with Snow Bunting representing the only
songbird to breed as far north as the Arctic Circle. Indeed, there is nothing
north of the snow bunting's breeding ground except the North Pole and the polar
ice cap. These passerines thrive in chilly, alpine conditions, playing and
singing in temperatures dipping as low as -20F. Although snow buntings (Plectrophenax nivalis) have
so far been considered common and widespread, enjoying stable numbers and
extensive nesting and wintering habitats, their North American populations have
shrunk by 64% over the past four decades, according to the National Audubon
Society .
These
alarming statistics may reflect how nature and wildlife are responding to
climate change and rising temperatures. Because snow buntings need snow and
cold, the increasingly warmer winters are the species' primary long-term
threat. And although considerable attention is currently being paid to the
conservation of migratory birds, this species remains still relatively
under-studied. New data and novel methods of research are needed to assess the
conservation implications of habitat changes in wintering locations as well as
the effects of climate change on their breeding success. Fresh light on the
migration patterns of remote populations of this avian species is shed by the
recent work of a group led and inspired by Prof. Oliver P. Love -- a wildlife biologist
from the University of Windsor in Ontario, Canada.
In the article "Strong Migratory Connectivity in a
Declining Arctic Passerine" published recently in Animal Migration -- an open access journal by Versita --
Christie Macdonald, a student of Love's, and her colleagues try to determine
how snow bunting populations are linked in space and time. Considering that the
snow bunting poses an extra challenge to monitor due to its inaccessible
breeding locations, nomadic lifestyle and small body size, they argue,
combining multiple sources of data is the most appropriate approach to track
patterns of the birds' migratory connectivity.
The
authors discovered that the population of snow buntings in North America is
divided. The individuals to the east of Hudson Bay do not regularly mix with
the ones to the west of Hudson Bay. These two sub-populations also migrate
different distances. The article supports the idea that thorough studies into
this species need to embrace a versatile mix of data -- including geolocator
technology, stable-isotope analysis , mark-recapture (banding) data along with
citizen science data. Macdonald and colleagues show strong evidence for an
east-west parallel migratory system, with Hudson Bay acting as a migratory
divide. While band recoveries suggest strong migratory connectivity among
eastern wintering populations (more than 95% of band recoveries reveal
connections between western Greenland and eastern North America), novel
application of geolocators and stable-hydrogen isotope analysis to a Canadian
breeding population reveal a high degree of migratory connectivity within
western North American wintering populations.
Both
sub-populations need to be conserved in order to save the overall population
and, more importantly, the effects of global warming and other anthropogenic
changes on one sub-population may be different from its effects on the other
sub-population.
The mixed-data approach described in Animal Migration (with geolocators being used for the first
time on arctic-breeding passerines) is innovative and still uncommon but a
better understanding of winter movement and connectivity between wintering and
breeding populations should help direct timely conservation efforts for this
and other iconic Canadian Arctic-breeding avian species.
Source: Versita
Leave Your Comments!
Share What’s Going on
in your brain about the Topic. We need Your Response . Feel free to leave comments!
Posted by Unknown
on Saturday, January 19, 2013.
Filed under
Earth And Climate
.
You can follow any responses to this entry through the RSS 2.0