A Preliminary Assessment of Burrowing Owl
Population Trends in New Mexico
Burrowing
Owls (Athene cunicularia) are a
species of concern due to their declining populations.
The North American Breeding Bird Survey
is widely used to monitor status and trends of bird populations as it is long-term,
large-scale, and well established. Estimates from the Breeding Bird Survey suggest
Burrowing Owl populations range-wide have declined at a rate of 1.1% per year
from 1966 to 2011.
Burrowing Owl distribution in New Mexico
Although
commonly believed they are declining in New Mexico, Breeding Bird Survey data
show an increasing trend in the state of 1.0% per year since 1966.
I
used GIS to examine if increasing trends in New Mexico are:
·
regional,
·
habitat
specific,
·
influenced
by our land use practices or land ownership,
·
or are influenced by climate
variables.
Analyses
suggest there is no apparent pattern in increasing or decreasing trends
regionally in NM or by bird conservation region or physiographic stratum.
Burrowing
Owl trends recorded on Breeding Bird Survey routes, New Mexico, USA.
Although
only a few route locations were compared for this project, preliminary results
suggest decreasing trends are associated with urban and agriculture land use
and vegetation types, and with higher temperatures and lower precipitation.
Comparison
of route habitats
Comparison
of route temperature and precipitation
In
New Mexico, there is very little information about the status of this species.
Because Breeding Bird Survey data are used by wildlife managers to establish
species status and trends, Burrowing Owls in NM may be falsely deemed secure if
the increasing trend is inaccurate or the drivers have negative implications.
Owls are frequently associated with agriculture and urban areas, and reported increases
in New Mexico may be due to land conversion and development. However, these
areas are also related to increased risk, such as chemical exposure, vehicle
collisions, increased predation, and burrow disturbance. In addition, climate
change projections of warming temperatures and decreased precipitation may
negatively affect Burrowing Owls in New Mexico and contribute to their decline.
Additional
analysis is needed to fully investigate the reported trends in New Mexico.
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here to see my next steps for FUTURE
WORK on this
project.
For
additional information on this project, please follow these links:
For more information on Burrowing
Owls, please visit:
New
Mexico Burrowing Owl Working Group