|
Effects of |
Approximately
70% of non-urban land in
Changes to small mammal populations as a
consequence of fuel reduction treatments in longleaf pine ecosystems
Changes to avifaunal populations as a
consequence of fuel reduction treatments in Longleaf Pine ecosystem
Effects of growing season prescribed fire on productivity and
survival of northern bobwhite populations (complete)
Mapping the distribution of longleaf ecosystems for
herpetofauna conservation (new)
Ecological assessment of habitats occupied by breeding
birds at Redstone Arsenal, Alabama (new)
Ecology
and management of black bears in the
Funding
Source: Earthwatch/the Center for Field Research
Principal
Investigator: Mike Mitchell, Roger A.
Powell (
Student:
Melissa Reynolds , Lara Brongo
Duration:
May 1999 - March 2006
The
objectives of this project are: (1) to use field sampling and GIS to develop
and evaluate fine-grain habitat maps for each year of research on black bears (Ursus americanus)
in the PBS 1981-1999, (2) to analyze field data collected in timber harvests,
model changes in habitat associated with harvests and building of roads, and
assess responses of bears to these changes, and (3) to employ population and
home range models to predict and evaluate demographic and behavioral responses
of bears to changes in habitat. Work to
date has resulted in spatial and temporal depictions of habitat quality and
food resources for the PBS from 1981 to 1994.
For these years we have also evaluated patterns in survivorship, use of
space, and relationships between home ranges and habitat quality for the bear
population. We have developed and tested
spatially explicit, individual-based models of optimal home range selection
that indicate a strong relationship between the size and shape of home ranges
and the spatial distribution of food resources in the sanctuary.
Status – Field work on this project ended
in 2002 and Melissa and Lara have been processing and analyzing data
since. Lara successfully defended her
Masters research in September 2004. Her
work evaluated demography of the Pisgah bear population over a 22- year
period. She was able to model vital
rates (population growth rate, survival, and reproduction) for the population
and show changes in the rates over time.
During a period when poaching pressure was high, the population suffered
high adult mortality and declined.
Following a law enforcement operation adult survival increased, as did
population growth rate. Recent evidence
suggests, however, that survival and population growth are again declining,
although the cause is not known. Lara
was able to demonstrate the population growth for the bears was most sensitive
to adult survival, refuting previous work that found juvenile survival to be
most important. As a side project, Lara
also found that baited trapping biased results of a bait station index
conducted in the vicinity of trap sites.
Two manuscripts from her work have been published in peer-reviewed
journals, a third is in work. Melissa
successfully completed her prelims in summer 2004 and continues her work
linking habitat quality to demography for bears, and landscape-scale effects of
forest management on their habitat. She
has submitted 2 manuscripts to peer-reviewed journals and has 4 other
manuscripts and 1 book chapter in work.
Manuscripts published from this project to date include 1 book chapter,
presentation and test of a habitat suitability index (HSI) for black bears in
the Wildlife Society Bulletin, an evaluation of the response of black bears to
forest management in the Journal of Wildlife Management, and a presentation of
optimal home range models in Ecological Modeling.
Changes
to small mammal populations as a consequence of fuel reduction treatments in
longleaf pine ecosystems
Funding
Source:
Principal
Investigator: Mike Mitchell
Student:
Nick Sharp
Duration:
May 2001 - December 2005
After
decades of fire suppression, a need exists for safe methods of returning
fire-dependent forest ecosystems to a natural condition and reducing the risk
of catastrophic and costly wildfires, particularly for systems near human
population centers that have unnaturally high fuel loads. Little is known about the response of animal
communities in fire-dependent forests to burning, or whether alternatives to
fire can satisfactorily emulate the positive effects of fire on these
communities. This uncertainty has led to
a nation-wide study sponsored by the USDA Forest Service addressing the effects
of fire reintroduction and alternatives in fire-dependent ecosystems
throughout the
Status – Fieldwork on Phase II
of this project began in 2002; the fourth season of fieldwork was completed in
2004. Stand treatments were applied
between the 2001 (pre-treatment) and 2002 (post-treatment) summer field seasons
except for herbicides which were applied after the 2002 field season. Trapping for small mammals was performed
during summer and winter field seasons of each year. To provide baseline information on small
mammals native to longleaf ecosystems, trapping was also conducted in
Changes
to avifaunal populations as a consequence of fuel reduction treatments in
Longleaf Pine ecosystem
Funding
Source:
Principal
Investigator: Mike Mitchell, Doug
Robinson (
Research
Assistant: Ghislain Rompré
Duration: June 2002 – December 2005
This study is the companion to the
small mammal project described above.
The objective of this research is to evaluate the responses of bird
populations breeding in the longleaf pine communities to fire and fire
alternatives. Results form this work
should provide insights into bird communities that inhabit longleaf forest, how
they respond to fire, and whether alternatives to fire can reduce fuel loads
while still providing adequate habitat.
The study consists of two parts: 1) assess the diversity and abundance
of birds responding to the treatments using point count censuses, and 2) assess
demographic responses of birds to treatments through monitoring
nest productivity (number of young fledged per nest initiated) and density
(through spot-mapping of bird territories) of nesting birds.
Status – Field work has
been completed on this project. From 1
April to 1 July 2004, over 60 bird species were detected by spot-mapping and
155 nests from 25 species were found. We
completed 3 rounds of point counts in all stands, generating more than 5,000
observations of birds. We found a high
number of nests for two species (eastern towhee Pipilo
erythrophthalmus, n = 30, Northern Cardinal, Cardinalis cardinalis,
n = 41). Other nests found were from a
variety of species including mourning dove, Zenaida
macroura,
Effects
of growing season prescribed fire on productivity and survival of northern bobwhite
populations (completed)
Funding
Source:
Principal
Investigator: Barry Grand
Student: Travis Folk
Duration: August 2001 – August 2005
Over the last 3 decades northern bobwhite (Colinus virginianus, hereafter bobwhite) populations have declined precipitously throughout the Southeastern and Midwestern United States. In the southeast, forested lands offer some of the best opportunities for bobwhite management. In stands of pine and mixed pine-hardwoods with low (<50%) canopy cover, frequent (1-3yr) controlled fires can be used to maintain the early successional, mainly herbaceous, understory vegetation required by breeding bobwhites. This habitat is typified by the "native" stands of longleaf pine (Pinus palustris) described by early explorers. Traditionally, prescribed fire has been applied during the winter months to reduce damage to desirable plant and animal populations. However, there is increasing support for the use of prescribed fire in longleaf pine forests during the growing season, because it may mimic the natural occurrence of lightning-caused wildfires and may favor the native condition of longleaf pine ecosystem preferred by some characteristic threatened and endangered species. This approach to forest ecosystem management may have adverse effects on populations of ground nesting birds including bobwhites, which may suffer nest losses and mortality when fire occurs during the growing season. The objective of this research is to determine the effects of controlled growing season fires on the productivity, survival, and growth rate of bobwhite populations in the longleaf pine ecosystem.
Status–The final field season
was completed in September 2004. In
total, 374 bobwhites were radio-marked and approximately 21,000 locations were
collected for these individuals over the 2 and one-half year duration of the
project. Analyses of survival, movement,
and female success of bobwhites were completed.
Age-based periodic population models were developed to represent summer
and winter seasons for bobwhite populations in
Funding
Source:
Principal
Investigator: James B. Grand
Co-principal
Investigator: Mark MacKenzie
(
Research
Assistant: Kevin Kleiner
Duration: August 2007 – August 2010
Over
the last two centuries, the longleaf pine ecosystem has been dramatically
altered by logging, replanting with other pine species, and fire
suppression. Current estimates, suggest
that longleaf occupies 5% of its pre-European settlement extent. This reduction in habitat has affected
numerous birds, reptiles, and amphibians.
The best known example of this is the red-cockaded woodpecker (Picoides borealis), a federally endangered
species that inhabits old growth longleaf pine woodlands. A reduction in the amount of habitat
available to this species has led to corresponding reductions in population
size.
The
gopher tortoise (Gopherus polyphemus)
and the black pine snake (Pituophis melanoleucus lodingi) are
also longleaf ecosystem inhabitants whose abundance is in decline. Successful management of both the gopher
tortoise and the black pine snake requires knowledge of the current
distribution of the longleaf pine ecosystem.
Currently, the course scale spatial distribution of longleaf pine can be
obtained from the USDA Forest Service’s Forest Inventory and Analysis Program
(FIA, Prasad and Iverson 2003). While useful for visualizing where longleaf
exists and perhaps planning at a regional scale, this product is not of
sufficient resolution for site specific wildlife conservation and management.
Another source that has the potential to provide the spatial distribution of
longleaf pine is remote sensing. In
2005, John Hogland, a graduate student at
Status
- We have
begun the process of collecting additional data for map assessment and
potential improvement. Recently acquired
data includes Forest Inventory and Analysis (FIA) plot data in
Funding
Source: Department of Defense
Principal
Investigator: Troy Best (
Graduate
Students: Lisa A. McWilliams and Charles
A. Kilgore
Duration: April 2007 – December 2008
The
state of
Redstone
Arsenal encompasses a variety of habitats within its 38,248 secured acres. It contains extensive wetland
areas associated with the
Twenty-eight species of birds are of special concern in
Considering
the need for information on avian diversity and ecological associations in the
region, an assessment of species present, distribution, breeding activity,
habitats occupied, etc., is highly desirable.
These data would be useful in developing management plans for the
Redstone Arsenal, and would provide baseline data for comparisons and future
research. This study will be a
significant contribution to overall assessment of presence, distribution,
breeding activities, and habitat associations of avian species of special
concern in
Status – Preliminary data on occurrence of birds at Redstone Arsenal were gathered during 2006 and 2007 incidental to research on bats. These data formed the basis for a preliminary report submitted to Redstone Arsenal in September 2007. During January-August 2008, field work will be conducted at Redstone Arsenal to assess species present, distribution on the facility, breeding activity, and habitats occupied. A final report will be submitted by 31 December 2008.