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Henriette I. Jager
Fish and
Wildlife Modeling in the Environmental Sciences Division (Read
more)
Current Projects
(last updated 3/2008)
Population Viability
Analysis of the Shortnose Sturgeon in the Ogeechee River
This
project seeks to quantitatively partition the influences on shortnose
sturgeon recovery that are under the control of the military and those that
are not. One goal is to quantify population extinction thresholds in terms of minimum numbers and habitat requirements. Results will be used to prioritize species recovery efforts for this endangered species. Using population viability analysis, we will quantify the cumulative and separate effects of (1) watershed management and military activities on water quality, (2)atmospheric mercury, (3) saltwater influx through rice canals, and (4) by-catch in the shad fishery, on the long-term persistence of the shortnose sturgeon population in rivers draining
Fort Stewart, Georgia.
(read more)
Population Viability
Analysis of Snake River Fall Chinook Salmon
We are developing a metapopulation model
of Snake River Fall Chinook Salmon for Idaho Power Company. The goal of the
project is to quantify the long-term extinction risk for this listed species. A metapopulation approach will allow
us to examine different assumptions about migration and correlations among
populations. In addition, the influence of life history diversity
(individuals following a "reservoir-type" life
history--overwintering in reservoirs was recently discovered) will be
examined.
Sustainability of Biomass
Crops
We are using the Soil Water Assessment
Tool (SWAT) model to quantify the effects of converting agricultural lands
from food production to production of crops for use as biomass fuels. My involvement is focused on two
questions: 1) Does the SWAT
(EPIC) model predict yield of switchgrass ecotypes adequately?, and 2) what
are the effects of converting lands on water quality (nutrient and soil
loadings to rivers and streams)?
Beyond this, we seek to evaluate management practices that will
minimize ecological impacts while developing this renewable, domestic source
of energy in a sustainable fashion.
Other Recent Projects
Ecological Valuation
In this ORNL seed project, headed by
Rebecca Efroymson, we examined the potential use of ecological models to
derive relative values for animal populations and their habitat. Ecological models were used to
transfer values from populations to habitat and vice versa, and to examine
how extinction thresholds influence use and non-use values, measured by
willingness-to-pay surveys.
Efroymson, Jager and Hargrove reviewed and projected future use of
population and landscape models in valuation of wildlands. Jager, Oladosu and Efroymson demonstrated
the combined use of a population model and an economic model in a case study
involving Chinook salmon. The
age-based population model showed that equilibrium population sizes increased
with total annual flow, whereas minimum viable population size decreased with
total annual flow. Marginal
willingness to pay for equilibrium population size was optimal at an
intermediate, but relatively low level of annual flow, whereas marginal
willingness to pay for minimum viable population size decreased with flow.
Population Viability
Analysis (PVA) of Snake River White Sturgeon
We
developed a PVA model for white sturgeon populations in the Snake
River to evaluate management alternatives that have been
proposed as part of relicensing for Middle Snake River dams. We used the PVA model to quantify the
effects of habitat fragmentation by dams on white sturgeon (Jager et al.
2000) in a theoretical river system. In 2001, we used the model to evaluate
the relative effects of various factors that have been implicated as playing
a role in population declines in some river segments (Jager et al. 2001). In
2002-2003, we simulated realistic strategies designed to reconnect fragmented
populations, (translocation and fish passage) with and without other
mitigation actions (e.g., reduced trash-rack spacing, improved water
quality). These simulations provided the White Sturgeon Technical Advisory
Committee with information needed to recommend conditions for relicensing
dams in the Middle Snake River. The model has since been used to evaluate
reconnection strategies involving translocation or upstream passage in rivers
with different configurations. In
2003-2004, the PVA model was used to evaluate demographic and genetic costs
and benefits of sturgeon aquaculture.
Because there are a number of different
factors that potentially influence white sturgeon in each river segment, we
designed specific models to address those questions. Mark Bevelhimer
developed a bioenergetic model to quantify the effects of load following
operations on white sturgeon growth and reproduction. He found that
temperature differences among the river segments alone explain significant
differences in reproductive potential over the lifetime of a female
(Bevelhimer 2002). This information feeds into the PVA model to quantify
population-level effects. Annett
Sullivan developed a spatial model designed to quantify the effects of water
quality in Brownlee Reservoir. She found that predictions of population-level
effects to depend on model assumptions about movement (Sullivan et al. 2003).
Our latest research has focused on
understanding the effects of small population size on extinction risk for
white sturgeon in the Columbia
River basin. We have compiled data for nearly all
populations of white sturgeon to better understand 1) whether there is a
minimum viable population size and 2) how habitat and metapopulation support
influence extinction risk. The
PVA model has also been used to examine this question for Snake
River populations.
(read more)
DOE Hydropower –
Environmental Mitigation and Hydropower Optimization
I am involved in two aspects of
ORNL’s research for the DOE Hydropower Program, managed by Mike
Sale. Mark Bevelhimer is leading
the effort to quantify the costs and benefits of instream-flow mitigation
practices on hydropower generation and on biological communities. I used intervention analysis to test
for a significant change in annual generation, accounting for year-to-year
variation in flow as a covariate.
We found that relicensing usually had a negative effect on generation,
presumably due to flow mitigation, but that the decrease was rarely
significant, even after removing the effects of year-to-year variation in
climate (flow). For hydropower
projects (i.e., dams) that changed from peaking to run-of-river operations,
we evaluated changes in the proportion of flow released during peak demand
using sub-daily flow data from USGS.
Results showed a reduction in this proportion following relicensing
primarily at dams with large storage capacity and no upstream
regulation. In several cases, the
proportion increased at dams passing through flow fluctuations from upstream
projects.
In a second project, Brennan Smith, and I
reviewed the state-of-the-science in optimization of hydropower with emphasis
on modeling non-power benefits. I
reviewed efforts to optimize hydropower operations for biological objectives,
or to constrain operations to protect biological resources.
Species Conservation and the
effects of Petroleum Extraction on BLM Lands
Rebecca
Efroymson is leading ORNL’s role in this collaboration between LLNL
(Tina Carlson), BLM, and ORNL. We
are using spatially explicit, individual-based models to study the effects of
habitat loss and fragmentation on bird and mammal populations of conservation
concern, including the prairie dog (LLNL) and either the sage grouse or
black-footed ferret (ORNL). One
aspect of the project is to develop quantitative methods for optimizing the
placement of wells to minimize harm to these populations.
Testing and Improvement of
the Oak Ridge Chinook salmon Model (ORCM) in the Tuolumne River, California
The
ORCM was developed between 1995 and 2000 and used to predict seasonal
patterns of flow that would maximize Chinook salmon recruitment from the Tuolumne River below New Don Pedro Dam. Since that time, nearly ten years of
monitoring have been conducted by Tim Heyne and others at the California
Department of Fish and Game, including rotary screw trapping of outmigrating
juveniles. This study, funded by
the California Energy Commission, had two objectives. First, we compared ORCM predictions to
these monitoring data, evaluated discrepancies, and made improvements to the
model or its parameters. We
conducted a functional validation in which we compared model and data
relationships between (measured or predicted) salmon outmigration and flow,
spawner density and degree-days. Autocorrelation in predictors were accounted
for in the analysis. After two sets of comparisons, agreement was adequate
for some years, but considerable differences remained for others. Second, we
developed imputation equations to use in estimating smolt outmigration.
Third, we implemented a routine to estimate the hydropower generation value
associated with simulated flow regimes.
Spatial Uncertainty in
Ecological Models
The goal of this project was to evaluate
the role of spatial uncertainty or error on projections from PVA and other
ecological models used by DoD. As
part of this SERDP-funded project, we (Tony King, Tom Ashwood, Barbara
Jackson and me) developed a method for generating stochastic simulations to
be used in spatial uncertainty analysis.
This approach was published in Ecological Modelling in 2005. We found that population
viability models were most sensitive for landscapes whose average spatial
statistical properties placed them near extinction thresholds (e.g., subject
to Allee effects).
Developing an Ecological Framework to Evaluate the Impacts of
Releases at Upstream Exploration and Production Sites
We developed an ecological
framework to evaluate the impacts of releases at petroleum exploration and
production sites. The project team at ORNL is headed by Rebecca Efroymson and
is using a case study at the Nature Conservancy's Tallgrass Prairie Preserve
in Oklahoma. We collaborated with Tina Carlsen and
Tanya Kostova at Lawrence Livermore National Laboratory. We developed a landscape model for
birds or mammals, with help from Eric Carr, and evaluated the simulated
effects of habitat loss and fragmentation on American badger
populations. We found that the
decline of population viability was steeper on fragmented landscapes, particularly
for a species like the American badger that does not avoid poor or risky
habitat. We also quantified Allee
effects caused by the failure to find mates in disturbed landscapes, which
suggests that the presence of unmated females defending territories might be
an early warning sign that densities are too low (Jager et al. Ecological
Modelling).
Conceptual PVA for Pallid
Sturgeon
In
this pilot project, I worked with Steve Krentz to develop a conceptual model
for pallid sturgeon, building on our experience with white sturgeon. In 2002,
I also implemented the code for this model, which simulates hybridization
between pallid and shovelnose sturgeon and hatchery stocking. The pallid
sturgeon is listed under the Endangered Species Act, and its recovery is the
concern of recovery teams throughout the Mississippi
and Missouri River basins. This study was funded
through the ORNL State Partnership Program, and involved collaborators at the
Western Area Power Administration (Ted Anderson) and US Fish and Wildlife (Steven
Krentz, Pallid sturgeon Recovery Team Leader).
Students involved in research
2007: Kendall Ernst, BS student from
Stanford U, worked on the Ogeechee shortnose
sturgeon project. Kendall implemented
the SWAT model to Fort
Stewart so that we
could examine the effects of changes in military landuse practices. He started the calibration process for
SWAT and compiled the spatial data needed to construct a 2D grid for the EFDC
hydrodynamic model of the Ogeechee and Canoochee rivers in Georgia.
2007: Sarah Lewis, recent Oak Ridge High School graduate, conducted a
literature search using ISI of water use efficiency in biomass crops and
produced an Endnote bibliography and a database of relevant data.
2006: Emmanuel Isang, BS student in
microbiology/pre-med at ETSU, conducted a literature search to support a life
history analysis of fishes that focuses on the relationship between the
number of years between spawning events and other costs associated with
spawning, such as parental care and migration.
2005: Darrell Hoy, BS student in
Mathematics, Dartmouth College,
NH, developed a variation on
tabu search optimization that we will use to optimize well placement to
minimize damage to sage grouse populations. Darrell also helped to develop a
graphical user interface using MFC for our white sturgeon PVA model.
2003: Liliya Hartman, BS student in
Computer Science, Pennsylvania,
helped to run simulations of hatchery operations (equalized family sizes
stocked) and their effects on the demographic and genetic health of a wild
population.
2002: Eric Carr, MS student in
Math, University
of Tennessee, coded the
object-oriented "badger" landscape model used to evaluate brine
spill effects in C++. This model
served as the basis for, and was generalized to represent a wide range of
terrestrial life histories and is currently being generalized further to
represent river habitats and aquatic species.
2001: Brian Maskarinec, BS in Math,
U. Georgia, developed the skeleton for an object-oriented landscape model,
reading an initial vegetation map and spatial disturbance data for fires, oil
spills, and brine spills
2000: Brian
Maskarinec, worked on our trout model to evaluate habitat use and its
response to flow in a California
stream.
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