Benjamin H Letcher
Ben Letcher is an Ecologist at the USGS Eastern Ecological Science Center in Turners Falls, Massachusetts.
Ben is a population ecologist focusing on stream habitats, science communication and the development of data systems. A collection of data systems and interactive data visualization tools can be found in our EcoSHEDS environment.
Professional Experience
1995-now USGS, Ecology section leader, Anadromous Fish Research Center, Turners, Falls, MA, and adjunct professor Department of Natural Resources
Conservation, University of Massachusetts - Amherst1994-1995 Oak Ridge Postdoctoral Fellow (with Dr. David Conover) State University of New York, Stony Brook, NY
1992-1994 Electric Power Research Institute Fellow, North Carolina State University, Raleigh, NC
1990-1992 Wisconsin Sea Grant Fellow, North Carolina State University, Raleigh, NC
1987-1990 URI-USEPA Cooperative Research Fellow, University of Rhode Island, Kingston, RI
1986-1987 Research Assistant, Center for Coastal Studies, Provincetown, MA.
1985-1986 Research Assistant, University of Massachusetts, Amherst, MA.
Education and Certifications
PhD, 1994, NC State, Zoology with statistics and modeling minor
M.S. 1990, URI School of Oceanography, biological option
B.S. 1985, Trinity College, Biology
Science and Products
Making decisions in complex landscapes: Headwater stream management across multiple federal agencies
Spatial variability in survival of adult brook trout within two intensively surveyed headwater stream networks
Estimating movement and survival rates of a small saltwater fish using autonomous antenna receiver arrays and passive integrated transponder tags
Modeling structured population dynamics using data from unmarked individuals
Basin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar)
Linking movement and reproductive history of brook trout to assess habitat connectivity in a heterogeneous stream network
GONe: Software for estimating effective population size in species with generational overlap
Sibship reconstruction for inferring mating systems, dispersal and effective population size in headwater brook trout (Salvelinus fontinalis) populations
Maintenance of phenotypic variation: Repeatability, heritability and size-dependent processes in a wild brook trout population
Fine-scale population structure and riverscape genetics of brook trout (Salvelinus fontinalis) distributed continuously along headwater channel networks
Variation in local abundance and species richness of stream fishes in relation to dispersal barriers: Implications for management and conservation
Use of portable antennas to estimate abundance of PIT-tagged fish in small streams: Factors affecting detection probability
Science and Products
- Publications
Filter Total Items: 92
Making decisions in complex landscapes: Headwater stream management across multiple federal agencies
Headwater stream ecosystems are vulnerable to numerous threats associated with climate and land use change. In the northeastern US, many headwater stream species (e.g., brook trout and stream salamanders) are of special conservation concern and may be vulnerable to climate change influences, such as changes in stream temperature and streamflow. Federal land management agencies (e.g., US Fish and WAuthorsRachel Katz, Evan H. Campbell Grant, Michael C. Runge, Bruce Connery, Marquette Crockett, Libby Herland, Sheela Johnson, Dawn Kirk, Jeb Wofford, Rick Bennett, Keith Nislow, Marian Norris, Daniel Hocking, Benjamin Letcher, Allison H. RoySpatial variability in survival of adult brook trout within two intensively surveyed headwater stream networks
Headwater stream networks are considered heterogeneous riverscapes, but it is challenging to characterize spatial variability in demographic rates. We estimated site-scale (50 m) survival of adult (>age 1+) brook trout (Salvelinus fontinalis) within two intensively surveyed headwater stream networks by applying an open-population N-mixture approach to count data collected over two consecutive summAuthorsYoichiro Kanno, Benjamin Letcher, Jason C. Vokoun, Elise ZipkinEstimating movement and survival rates of a small saltwater fish using autonomous antenna receiver arrays and passive integrated transponder tags
We evaluated the performance of small (12.5 mm long) passive integrated transponder (PIT) tags and custom detection antennas for obtaining fine-scale movement and demographic data of mummichog Fundulus heteroclitus in a salt marsh creek. Apparent survival and detection probability were estimated using a Cormack Jolly Seber (CJS) model fitted to detection data collected by an array of 3 vertical anAuthorsPaul J. Rudershausen, Jeffery A. Buckel, Todd Dubreuil, Matthew J. O'Donnell, Joseph E. Hightower, Steven J. Poland, Benjamin H. LetcherModeling structured population dynamics using data from unmarked individuals
The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark–recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters aAuthorsEvan H. Campbell Grant, Elise Zipkin, James T. Thorson, Kevin See, Heather J. Lynch, Yoichiro Kanno, Richard Chandler, Benjamin H. Letcher, J. Andrew RoyleBasin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar)
Migrations between different habitats are key events in the lives of many organisms. Such movements involve annually recurring travel over long distances usually triggered by seasonal changes in the environment. Often, the migration is associated with travel to or from reproduction areas to regions of growth. Young anadromous Atlantic salmon (Salmo salar) emigrate from freshwater nursery areas durAuthorsJaime Otero, Jan Henning L’Abée-Lund, Theodore Castro-Santos, Kjell Leonardsson, Geir O. Storvik, Bror Jonsson, J. Brian Dempson, Ian C. Russell, Arne J. Jensen, Jean-Luc Baglinière, Mélanie Dionne, John D. Armstrong, Atso Romakkaniemi, Benjamin Letcher, John F. Kocik, Jaakko Erkinaro, Russell Poole, Ger Rogan, Hans Lundqvist, Julian C. MacLean, Erkki Jokikokko, Jo Vegar Arnekleiv, Richard J. Kennedy, Eero Niemelä, Pablo Caballero, Paul A. Music, Thorolfur Antonsson, Sigurdur Gudjonsson, Alexey E. Veselov, Anders Lamberg, Steve Groom, Benjamin H. Taylor, Malcolm Taberner, Mary Dillane, Fridthjofur Arnason, Gregg E. Horton, Nils A. Hvidsten, Ingi R. Jonsson, Nina Jonsson, Simon McKelvey, T. F. Naesje, Øystein Skaala, Gordon W. Smith, Harald Sægrov, N. C. Stenseth, Leif Asbjørn VøllestadLinking movement and reproductive history of brook trout to assess habitat connectivity in a heterogeneous stream network
1. Defining functional connectivity between habitats in spatially heterogeneous landscapes is a particular challenge for small-bodied aquatic species. Traditional approaches (e.g. mark–recapture studies) preclude an assessment of animal movement over the life cycle (birth to reproduction), and movement of individuals may not represent the degree of gene movement for fecund species. We investigatedAuthorsYoichiro Kanno, Benjamin H. Letcher, Jason A. Coombs, Keith H. Nislow, Andrew R. WhiteleyGONe: Software for estimating effective population size in species with generational overlap
GONe is a user‐friendly, Windows‐based program for estimating effective size (Ne) in populations with overlapping generations. It uses the Jorde–Ryman modification to the temporal method to account for age structure in populations. This method requires estimates of age‐specific survival and birth rate and allele frequencies measured in two or more consecutive cohorts. Allele frequencies are acquirAuthorsJ.A. Coombs, B. H. Letcher, K.H. NislowSibship reconstruction for inferring mating systems, dispersal and effective population size in headwater brook trout (Salvelinus fontinalis) populations
Brook trout Salvelinus fontinalis populations have declined in much of the native range in eastern North America and populations are typically relegated to small headwater streams in Connecticut, USA. We used sibship reconstruction to infer mating systems, dispersal and effective population size of resident (non-anadromous) brook trout in two headwater stream channel networks in Connecticut. BrookAuthorsYoichiro Kanno, Jason C. Vokoun, Benjamin H. LetcherMaintenance of phenotypic variation: Repeatability, heritability and size-dependent processes in a wild brook trout population
Phenotypic variation in body size can result from within-cohort variation in birth dates, among-individual growth variation and size-selective processes. We explore the relative effects of these processes on the maintenance of wide observed body size variation in stream-dwelling brook trout (Salvelinus fontinalis). Based on the analyses of multiple recaptures of individual fish, it appears that siAuthorsB. H. Letcher, J.A. Coombs, K.H. NislowFine-scale population structure and riverscape genetics of brook trout (Salvelinus fontinalis) distributed continuously along headwater channel networks
Linear and heterogeneous habitat makes headwater stream networks an ideal ecosystem in which to test the influence of environmental factors on spatial genetic patterns of obligatory aquatic species. We investigated fine-scale population structure and influence of stream habitat on individual-level genetic differentiation in brook trout (Salvelinus fontinalis) by genotyping eight microsatellite locAuthorsYoichiro Kanno, Jason C. Vokoun, Benjamin H. LetcherVariation in local abundance and species richness of stream fishes in relation to dispersal barriers: Implications for management and conservation
1.Barriers to immigration, all else being equal, should in principle depress local abundance and reduce local species richness. These issues are particularly relevant to stream-dwelling species when improperly designed road crossings act as barriers to migration with potential impacts on the viability of upstream populations. However, because abundance and richness are highly spatially and temporaAuthorsK.H. Nislow, M. Hudy, B. H. Letcher, E.P. SmithUse of portable antennas to estimate abundance of PIT-tagged fish in small streams: Factors affecting detection probability
Portable passive integrated transponder (PIT) tag antenna systems can be valuable in providing reliable estimates of the abundance of tagged Atlantic salmon Salmo salar in small streams under a wide range of conditions. We developed and employed PIT tag antenna wand techniques in two controlled experiments and an additional case study to examine the factors that influenced our ability to estimateAuthorsMatthew J. O'Donnell, Gregg E. Horton, Benjamin H. Letcher - Science
Filter Total Items: 17
- Data
- Multimedia
- Web Tools
- Software