The USGS Alaska Science Center Ecosystems Analytics program is a group of quantitative biologists and research statisticians who provide analytical support to USGS scientists to answer challenging ecological topics and management questions for USGS partners.
Emily L Weiser, Ph.D.
Emily Weiser is a Wildlife Biologist providing quantitative support to projects at the Alaska Science Center.
Previously, Emily provided statistical support to the Monarch Conservation Science Partnership to develop a continental-scale sampling strategy for monarch butterflies and the resources that sustain them, collaborated with a large network of researchers to conduct demographic analyses for shorebirds in the Arctic, worked closely with conservation managers to improve genetic and demographic viability of forest birds in New Zealand, and worked with partners on Alaska's North Slope to assess the effects of human activity on Glaucous Gulls and their prey.
Professional Experience
2019 - Present: Wildlife Biologist, Alaska Science Center, U.S. Geological Survey, Anchorage, AK
2016 - 2019: Biologist, Upper Midwest Environmental Sciences Center, U.S. Geological Survey, La Crosse, WI
2014 - 2016: Postdoctoral Research Associate, Kansas State University, Manhattan, KS
Education and Certifications
PhD, Zoology, University of Otago (Dunedin, New Zealand); 2014
MSc, Wildlife Biology, University of Alaska Fairbanks; 2010
BA, Biology, Colby College (Maine, USA); 2004
Science and Products
Geese migrating over the Pacific Ocean select altitudes coinciding with offshore wind turbine blades
Optimizing surveys of fall-staging geese using aerial imagery and automated counting
Fully accounting for nest age reduces bias when quantifying nest survival
TrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends
Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska
Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain
Evidence for a growing population of eastern migratory monarch butterflies is currently insufficient
Challenges for leveraging citizen science to support statistically robust monitoring programs
Is the timing, pace and success of the monarch migration associated with sun angle?
Balancing sampling intensity against spatial coverage for a community science monitoring programme
Technical comment on “Global pattern of nest predation is disrupted by climate change in shorebirds”
Geographic variation in the intensity of warming and phenological mismatch between Arctic shorebirds and invertebrates
Ecosystems Analytics
Q&A: USGS and the 2023 Anchorage Bike to Work Day
Q&A: Improving Aerial Surveys of Geese in Alaska with Aerial Imagery
TrendPowerTool: A web lookup tool for estimating the statistical power of a monitoring program to detect population trends
Monarch Conservation Science Partnership Map Viewer and Tools
Monarch Conservation Science Partnership
Movement Data for Migrating Geese Over the Northeast Pacific Ocean, 2018-2021
Aerial Photo Imagery from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
Counts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
Nest Survival Bias Analysis
The USGS Alaska Science Center Ecosystems Analytics program is a group of quantitative biologists and research statisticians who provide analytical support to USGS scientists to answer challenging ecological topics and management questions for USGS partners.
Semipalmated Sandpipers with A) Leg bands only (no flag), or B) leg bands plus flag From: Leg flags do not affect shorebird nests: https://doi.org/10.1111/jofo.12264
Semipalmated Sandpipers with A) Leg bands only (no flag), or B) leg bands plus flag From: Leg flags do not affect shorebird nests: https://doi.org/10.1111/jofo.12264
Photo equipment used to take pictures of fall staging migratory geese at Izembek Lagoon, Alaska. Scientists from the USGS Alaska Science Center and the U.S.
Photo equipment used to take pictures of fall staging migratory geese at Izembek Lagoon, Alaska. Scientists from the USGS Alaska Science Center and the U.S.
Channels and mudflats of Izembek Lagoon, Alaska, taken from a USFWS survey aircraft. Photo Courtesy of U.S. Fish and Wildlife Service, Public Domain. Dennis Marks USFWS photographer.
Channels and mudflats of Izembek Lagoon, Alaska, taken from a USFWS survey aircraft. Photo Courtesy of U.S. Fish and Wildlife Service, Public Domain. Dennis Marks USFWS photographer.
Eunbi Kwon, a PhD student at Kansas State University at that time, researching the breeding ecology of shorebirds breeding at Nome as part of the Arctic Shorebird Demographics Network collaboration. The bird was marked to allow it to be individually identified when it returned to the study area.
Eunbi Kwon, a PhD student at Kansas State University at that time, researching the breeding ecology of shorebirds breeding at Nome as part of the Arctic Shorebird Demographics Network collaboration. The bird was marked to allow it to be individually identified when it returned to the study area.
Red-necked Phalarope hatchlings (chicks). The photo was taken at Prudhoe Bay, Alaska as part of nest-monitoring research.
Red-necked Phalarope hatchlings (chicks). The photo was taken at Prudhoe Bay, Alaska as part of nest-monitoring research.
Proportion of time that Pacific Flyway geese are at risk of wind-turbine strikes during transoceanic migrations
This tool shows the proportion of goose locations expected to be in or below a user-specified rotor-swept zone based on expected goose flight altitudes.
Scripts to Analyze Altitude Selection in Migrating Pacific Flyway Geese
R scripts for analysis of fall photographic waterfowl surveys, Izembek NWR, Alaska, 2017-2019
Nest Survival Bias Analysis
This R script will run one replicate of one scenario used by Weiser (in review) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the end of
Arctic Shorebird Population Model
GRTS for Integrated Monarch Monitoring Program Code
Science and Products
- Publications
Filter Total Items: 17
Geese migrating over the Pacific Ocean select altitudes coinciding with offshore wind turbine blades
Renewable energy facilities are a key part of mitigating climate change, but can pose threats to wild birds and bats, most often through collisions with infrastructure. Understanding collision risk and the factors affecting it can help minimize impacts on wild populations. For wind turbines, flight altitude is a major factor influencing collision risk, and altitude-selection analyses can evaluateAuthorsEmily L. Weiser, Cory T. Overton, David C. Douglas, Michael L. Casazza, Paul L. FlintOptimizing surveys of fall-staging geese using aerial imagery and automated counting
Ocular aerial surveys allow efficient coverage of large areas and can be used to monitor abundance and distribution of wild populations. However, uncertainty around resulting population estimates can be large due to difficulty in visually identifying and counting animals from aircraft, as well as logistical challenges in estimating detection probabilities. Photographic aerial surveys can mitigateAuthorsEmily L. Weiser, Paul L. Flint, Dennis K Marks, Brad S Shults, Heather M. Wilson, Sarah J Thompson, Julian B. FischerFully accounting for nest age reduces bias when quantifying nest survival
Accurately measuring nest survival is challenging because nests must be discovered to be monitored, but nests are typically not found on the first day of the nesting interval. Studies of nest survival therefore often monitor a sample that overrepresents older nests. To account for this sampling bias, a daily survival rate (DSR) is estimated and then used to calculate nest survival to the end of thAuthorsEmily L. WeiserTrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends
A simulation-based power analysis can be used to estimate the sample sizes needed for a successful monitoring program, but requires technical expertise and sometimes extensive computing resources. We developed a web-based lookup app, called TrendPowerTool (https://www.usgs.gov/apps/TrendPowerTool/), to provide guidance for ecological monitoring programs when resources are not available for a simulAuthorsEmily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. ThogmartinSample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska
Authorization of lease sales for oil development in the 1002 Area of the Arctic National Wildlife Refuge has highlighted gaps in information about biological communities in the area. The U.S. Fish and Wildlife Service, which is planning a study to evaluate spatial variation in the nest survival of tundra-breeding shorebirds to identify hotspots with high nest survival, sought advice from the U.S.AuthorsEmily L. WeiserAnnual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain
Conservation status and management priorities are often informed by population trends. Trend estimates can be derived from population surveys or models, but both methods are associated with sources of uncertainty. Many Arctic-breeding shorebirds are thought to be declining based on migration and/or overwintering population surveys, but data are lacking to estimate the trends of some shorebird specAuthorsEmily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, Joel Bety, Megan L. Boldenow, Rodney W. Brook, Glen S. Brown, Willow B. English, Scott A. Flemming, Samantha E. Franks, H. Grant Gilchrist, Marie-Andree Giroux, Andrew C. Johnson, Steve Kendall, Lisa V. Kennedy, Laura Koloski, Eunbi Kwon, Jean-Francois Lamarre, David B. Lank, Christopher J. Latty, Nicolas Lecomte, Joseph R. Liebezeit, Rebecca L McGuire, Laura McKinnon, Erica Nol, David C. Payer, Johanna Perz, Jennie Rausch, Martin D. Robards, Sarah T. Saalfeld, Nathan R. Senner, Paul A. Smith, Mikhail Soloviev, Diana V Solovyeva, David H. Ward, Paul F. Wood, Brett K. SandercockEvidence for a growing population of eastern migratory monarch butterflies is currently insufficient
The eastern migratory population of monarch butterflies has experienced a multi-decadal decline, but a recent increase in abundance (to 6.05 ha in winter 2018) has led some observers to question whether the population has reversed its long-standing decline and embarked on a trajectory of increasing abundance. We examined this possibility through changepoint analyses, first assessing whether a chanAuthorsWayne E. Thogmartin, Jennifer A Szymanski, Emily L. WeiserChallenges for leveraging citizen science to support statistically robust monitoring programs
Large samples and long time series are often needed for effective broad-scale monitoring of status and trends in wild populations. Obtaining those sample sizes can be more feasible when volunteers contribute to the dataset, but volunteer-selected sites are not always representative of a population. Previous work to account for biased site selection has relied on knowledge of covariates to explainAuthorsEmily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. ThogmartinIs the timing, pace and success of the monarch migration associated with sun angle?
A basic question concerning the monarch butterfly’s fall migration is which monarchs succeed in reaching overwintering sites in Mexico, which fail—and why. We document the timing and pace of the fall migration, ask whether the sun’s position in the sky is associated with the pace of the migration, and whether timing affects success in completing the migration. Using data from the Monarch Watch tagAuthorsOrley R. Taylor, James P Lovett, David L Gibo, Emily L. Weiser, Wayne E. Thogmartin, Darius J. Semmens, James E. Diffendorfer, John M. Pleasants, Samuel Pecoraro, Ralph GrundelBalancing sampling intensity against spatial coverage for a community science monitoring programme
Community science is an increasingly integral part of biodiversity research and monitoring, often achieving broad spatial and temporal coverage but lower sampling intensity than studies conducted by professional scientists. When designing a community‐science monitoring programme, careful assessment of sampling designs that could be both feasible and successful at meeting programme goals is essentiAuthorsEmily L. Weiser, Jay E. Diffendorfer, Ralph Grundel, Laura Lopez Hoffman, Samuel Pecoraro, Darius J. Semmens, Wayne E. ThogmartinTechnical comment on “Global pattern of nest predation is disrupted by climate change in shorebirds”
Kubelka et al. (Report, 9 November 2018, p. 680-683) claim that climate change has disrupted patterns of nest predation in shorebirds. They report that predation rates have increased since the 1950s, especially in the Arctic. We describe methodological problems with their analyses and argue that there is no solid statistical support for their claims.AuthorsMartin Bulla, Jeroen Reneerkens, Emily L. Weiser, Aleksandr Sokolov, Audrey R. Taylor, Benoit Sittler, Brian J McCaffery, Daniel R. Ruthrauff, Daniel H. Catlin, David C. Payer, David H. Ward, Diana V Solovyeva, Eduardo SA Santos, Eldar Rakhimberdiev, Erica Nol, Eunbi Kwon, Glen S. Brown, Glenda D Hevia, H. River Gates, James A. Johnson, Jan A. van Gils, Jannik Hansen, Jean-Francois Lamarre, Jennie Rausch, Jesse R. Conklin, Joe Liebezeit, Joel Bety, Johannes Lang, José A. Alves, Juan Fernandez-Elipe, Klaus-Michael Exo, Loic Bollache, Marcelo Bertellotti, Marie-Andree Giroux, Martijn van de Pol, Matthew D. Johnson, Megan L. Boldenow, Mihai Valcu, Mikhail Soloviev, Natalya Sokolova, Nathan R. Senner, Nicholas Lecomte, Nicolas Meyer, Niels Martin Schmidt, Olivier Gilg, Paul A Smith, Paula Machin, Rebecca L McGuire, Ricardo AS Cerboncini, Richard Ottvall, Rob SA van Bemmelen, Rose J Swift, Sara T Saalfeld, Sara E Jamieson, Stephen C. Brown, Theunis Piersma, Tomas Albrecht, Veronica L D'Amico, Richard B. Lanctot, Bart KempenaersGeographic variation in the intensity of warming and phenological mismatch between Arctic shorebirds and invertebrates
Responses to climate change can vary across functional groups and trophic levels, leading to a temporal decoupling of trophic interactions or ‘phenological mismatches.’ Despite a growing number of single-species studies that identified phenological mismatches as a nearly universal consequence of climate change, we have a limited understanding of the spatial variation in the intensity of this phenoAuthorsEnubi Kwon, Emily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, H. Grant Gilchrist, Steve J. Kendall, David B. Lank, Joseph R. Liebezeit, Laura McKinnon, Erica Nol, David C. Payer, Jennie Rausch, Sarah T. Saalfeld, Daniel J. Rinella, Nathan R. Senner, David Ward, Paul A. Smith, Robert C. Wissman, Brett K. Sandercock - Science
Ecosystems Analytics
Ecosystems Analytics is a group of quantitative biologists and research statisticians with a diverse range of expertise and experience (summarized below). We collaborate with internal and external partners to answer challenging ecological questions that are a high priority of the U.S. Geological Survey Alaska Science Center, sister agencies within the Department of the Interior (DOI), and various...Q&A: USGS and the 2023 Anchorage Bike to Work Day
For the 2023 Anchorage Bike to Work Day , the USGS Alaska Science Center will host a “treat station” along the Lanie Fleischer Chester Creek Trail where people can learn about the USGS streamgage on the creek and about common birds of Chanshtnu.Q&A: Improving Aerial Surveys of Geese in Alaska with Aerial Imagery
Thousands of geese gather at Izembek Lagoon in southwestern Alaska every fall where they “stage”, meaning that they rest and eat in preparation for migration to lower latitudes. Izembek Lagoon is especially important for Pacific brant geese, as the entire Pacific Flyway population is thought to use the lagoon in fall. This provides an opportunity to efficiently survey the population to track...TrendPowerTool: A web lookup tool for estimating the statistical power of a monitoring program to detect population trends
A simulation-based power analysis can be used to estimate the sample sizes needed for a successful monitoring program, but requires technical expertise and sometimes extensive computing resources. We developed a web-based lookup app, called TrendPowerTool, to provide guidance for ecological monitoring programs when resources are not available for a simulation-based power analysis (Fig. 1)...Monarch Conservation Science Partnership Map Viewer and Tools
This web mapping application is a repository for data and tools that support the Monarch Conservation Science Partnership.Monarch Conservation Science Partnership
The Challenge Over the last two decades, the Eastern migratory population of monarch butterflies has declined by about 80%, leading many scientists to consider how to best conserve and rebuild monarch populations. Conservation efforts can be challenging to design and execute because of the multi-generational migration of monarchs that spans North America. Conservationists must consider many... - Data
Movement Data for Migrating Geese Over the Northeast Pacific Ocean, 2018-2021
This dataset consists of one table with a record (row) for each goose location and columns containing location information and covariates. The dataset was used in an analysis of altitude selection and flight propensity in an accompanying paper (Weiser et al. 2024) and is being provided here to allow replication of that analysis. Goose locations (latitude, longitude, and altitude) were collected wiAerial Photo Imagery from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
The imagery and annotations presented here were generated while testing an aerial photographic survey design to improve repeatability, transparency, and estimation of variance for annual population estimates of geese staging at Izembek Lagoon, Alaska. This dataset includes 1) 131,031 .JPG images captured from a small fixed-wing occupied aircraft, usually at an altitude of about 457 m, over IzembekCounts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
This dataset includes tables summarizing image information and bird counts from the aerial digital images taken over open water at Izembek Lagoon in Alaska in fall 2017-2019. These summaries list one record per image and provide the camera parameters, latitude, longitude, altitude, and automated and manual counts representing the total number of birds in each taxon (brant, white-cheeked geese, empNest Survival Bias Analysis
This R script will run one replicate of one scenario used by Weiser (in review) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the end of - Multimedia
USGS Alaska Science Center Ecosystems Analytics ProgramUSGS Alaska Science Center Ecosystems Analytics ProgramUSGS Alaska Science Center Ecosystems Analytics Program
The USGS Alaska Science Center Ecosystems Analytics program is a group of quantitative biologists and research statisticians who provide analytical support to USGS scientists to answer challenging ecological topics and management questions for USGS partners.
The USGS Alaska Science Center Ecosystems Analytics program is a group of quantitative biologists and research statisticians who provide analytical support to USGS scientists to answer challenging ecological topics and management questions for USGS partners.
Semipalmated Sandpipers with leg bands or leg bands plus flagSemipalmated Sandpipers with leg bands or leg bands plus flagSemipalmated Sandpipers with A) Leg bands only (no flag), or B) leg bands plus flag From: Leg flags do not affect shorebird nests: https://doi.org/10.1111/jofo.12264
Semipalmated Sandpipers with A) Leg bands only (no flag), or B) leg bands plus flag From: Leg flags do not affect shorebird nests: https://doi.org/10.1111/jofo.12264
Photo equipment used for fall staging migratory geesePhoto equipment used for fall staging migratory geesePhoto equipment used to take pictures of fall staging migratory geese at Izembek Lagoon, Alaska. Scientists from the USGS Alaska Science Center and the U.S.
Photo equipment used to take pictures of fall staging migratory geese at Izembek Lagoon, Alaska. Scientists from the USGS Alaska Science Center and the U.S.
Channels and mudflats of Izembek Lagoon, AlaskaChannels and mudflats of Izembek Lagoon, Alaska, taken from a USFWS survey aircraft. Photo Courtesy of U.S. Fish and Wildlife Service, Public Domain. Dennis Marks USFWS photographer.
Channels and mudflats of Izembek Lagoon, Alaska, taken from a USFWS survey aircraft. Photo Courtesy of U.S. Fish and Wildlife Service, Public Domain. Dennis Marks USFWS photographer.
Eunbi Kwon holding a Western Sandpiper, Nome, AlaskaEunbi Kwon holding a Western Sandpiper, Nome, AlaskaEunbi Kwon, a PhD student at Kansas State University at that time, researching the breeding ecology of shorebirds breeding at Nome as part of the Arctic Shorebird Demographics Network collaboration. The bird was marked to allow it to be individually identified when it returned to the study area.
Eunbi Kwon, a PhD student at Kansas State University at that time, researching the breeding ecology of shorebirds breeding at Nome as part of the Arctic Shorebird Demographics Network collaboration. The bird was marked to allow it to be individually identified when it returned to the study area.
Red-necked Phalarope hatchlings, Prudhoe Bay, AlaskaRed-necked Phalarope hatchlings, Prudhoe Bay, AlaskaRed-necked Phalarope hatchlings (chicks). The photo was taken at Prudhoe Bay, Alaska as part of nest-monitoring research.
Red-necked Phalarope hatchlings (chicks). The photo was taken at Prudhoe Bay, Alaska as part of nest-monitoring research.
- Web Tools
Proportion of time that Pacific Flyway geese are at risk of wind-turbine strikes during transoceanic migrations
This tool shows the proportion of goose locations expected to be in or below a user-specified rotor-swept zone based on expected goose flight altitudes.
- Software
Scripts to Analyze Altitude Selection in Migrating Pacific Flyway Geese
This code repo contains three scripts used in the associated manuscript to run the analyses (01_model_prob_flight.r; 02_model_altitude_selection.r) and the simulation used to make predictions (03_simulate_prob_fly_per_altitude.r). The analysis serves to evaluate conditions that affect 1) whether geese are in flight vs. resting on the water, 2) what altitude is selected by flying geese, and 3) whatR scripts for analysis of fall photographic waterfowl surveys, Izembek NWR, Alaska, 2017-2019
This code repo contains three novel scripts used in Weiser et al. (2022): one to calculate the footprint of an aerial photo (01_function_photo_footprint.r), one to run a simulation to evaluate sample sizes for the photographic survey (02_photo_sample_size_sim.r), and one to run a simulation to evaluate sample sizes for the ocular survey (03_ocular_sample_size_sim.r). For more information on the baNest Survival Bias Analysis
This R script will run one replicate of one scenario used by Weiser (in review) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the end of
Arctic Shorebird Population Model
R script to run one example of the stochastic matrix models run by Weiser et al. to simulate shorebird population trends and elasticities.GRTS for Integrated Monarch Monitoring Program Code
These scripts prepare input files and run a Generalized Random Tessellation Stratified (GRTS) draw to select sampling locations for the Integrated Monarch Monitoring Program in the U.S., Canada, and Mexico. - News