Theodore Castro-Santos
Research Ecologist at the Eastern Ecological Science Center's S.O. Conte Research Laboratory in Turners Falls, MA
Human activities have caused extensive fragmentation of riverine corridors. Dams, culverts, and other barriers prevent migratory and riverine fishes from accessing key habitats. This is particularly problematic for diadromous fishes like Atlantic salmon and American shad that must transition between fresh- and saltwater habitats in order to complete their life cycles. Swimming performance and behavioral responses to hydraulic conditions (turbulence, velocity, etc.) are major interests, as is development of quantitative methods for identifying and characterizing barriers. This work has broad relevance, not only to stewardship and management of aquatic resources, but also to understanding fundamental aspects of the ecology and evolution of fishes. Some current projects include:
- Sprint-swimming performance of migratory and riverine species
- Effects of turbulence on swimming performance, biomechanics, and behavior
- Modeling fish passage through culverts
- Bioenergetics models of anadromous fish migration
Professional Experience
US Geological Survey (1995-present)
U.S. Fish and Wildlife Service (1992-1995)
Education and Certifications
PhD Organismic and Evolutionary Biology; University of Massachusetts Amherst (2002)
MS Wildlife Biology Washington State University (1991)
BA Colgate University (1987)
Affiliations and Memberships*
American Fisheries Society
Society for Integrative and Comparative Biology
Science and Products
Filter Total Items: 80
Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad
This paper describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon (N=75) and upstream migrating adult American shad (N=208). Controlled studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control...
Authors
Theodore R. Castro-Santos, Alex Haro
Passage of native riverine fishes through geometrically different sections of a vertical slot fishway on the Moselle River, Germany Passage of native riverine fishes through geometrically different sections of a vertical slot fishway on the Moselle River, Germany
In order to study effects of different geometric types of pools or change of the flow direction on the passability of fish, sets of PIT antennas were installed inside a modern vertical slot fishway at the mouth of the River Moselle. Fish of 13 abundant species were caught and tagged with PIT tags in 2013 and released in the tailwater of Koblenz. 16% of the tagged fish were detected...
Authors
Matthias Pitsch, Bernd Mockenhaupt, Theodore R. Castro-Santos
Basin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar) Basin-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...
Authors
Jaime Otero, Jan Henning L’Abee-Lund, Theodore Castro-Santos, Kjell Leonardsson, Geir O. Storvik, Bror Jonsson, J. Brian Dempson, Ian C. Russell, Arne J. Jensen, Jean-Luc Bagliniere, Mélanie Dionne, John D. Armstrong, Atso Romakkaniemi, Benjamin H. Letcher, John F. Kocik, Jaakko Erkinaro, Russell Poole, Ger Rogan, Hans Lundqvist, Julian C. MacLean, Erkki Jokikokko, Jo Vegar Arnekleiv, Richard J. Kennedy, Eero Niemela, 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, Oystein Skaala, Gordon W. Smith, Harald Saegrov, N. C. Stenseth, Leif Asbjørn Vøllestad
Posthandling survival and PIT tag retention by alewives—a comparison of gastric and surgical implants Posthandling survival and PIT tag retention by alewives—a comparison of gastric and surgical implants
We compared survival and tag retention of Alewives Alosa pseudoharengus tagged with PIT tags, using intraperitoneal (IP) surgical implants, gastric implants (GI), and untagged controls held for 38 d. Retention was 100% for IP-tagged Alewives and 98% for GI-tagged implants. No significant difference in survival was observed among any of these groups. These results lend support to the use...
Authors
Theodore Castro-Santos, Volney Voni
Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta)
Sprinting behavior of free-ranging fish has long been thought to exceed that of captive fish. Here we present data from wild-caught brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta), volitionally entering and sprinting against high-velocity flows in an open-channel flume. Performance of the two species was nearly identical, with the species attaining absolute speeds > 25...
Authors
Theodore Castro-Santos, Francisco Javier Sanz-Ronda, Jorge Ruiz-Legazpi
A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin
The majority of the fish passages built in the Neotropical region are characterised by low efficiency and high selectivity; in many cases, the benefits to fish populations are uncertain. Studies conducted in the Canal da Piracema at Itaipu dam on the Parana River indicate that the system component designated as the Discharge channel in the Bela Vista River (herein named Canal de deságue...
Authors
Theodore R. Castro-Santos, Helio Martins Fontes, Sergio Makrakis, Luiz Carlos Gomes, Joao Dirco Latini
Culverts in paved roads as suitable passages for neotropical fish species Culverts in paved roads as suitable passages for neotropical fish species
Improperly installed or poorly maintained culverts can pose a serious threat to fish by disrupting their habitat and endangering spawning success. Road culverts that are not designed for fish passage frequently can become obstacles. This can be especially problematic for migratory species, but can lead to fragmentation of resident populations as well. This study evaluated 40 culverts of...
Authors
Sergio Makrakis, Theodore R. Castro-Santos, Maristela Cavicchioli Makrakis, Ricardo Luiz Wagner, Mauricio Spagnolo Adames
Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent
This paper presents results of a fishway evaluation performed at the Engenheiro Sérgio Motta Hydroelectric Power Plant (known as Porto Primavera) - CESP, Paraná River, Brazil. The evaluation was designed to quantify entry and passage proportions of 4 long-distance migratory fish species: Brycon orbignyanus (piracanjuba), Piaractus mesopotamicus (pacu), Prochilodus lineatus (curimba), and
Authors
Ricardo Luiz Wagner, Sergio Makrakis, Theodore R. Castro-Santos, Maristela Cavicchioli Makrakis, Joao Henrique Pinheiro Dias, Rene Fuster Belmont
Time-to-event analysis as a framework for quantifying fish passage performance Time-to-event analysis as a framework for quantifying fish passage performance
Fish passage is the result of a sequence of processes, whereby fish must approach, enter, and pass a structure. Each of these processes takes time, and fishway performance is best quantified in terms of the rates at which each process is completed. Optimal performance is achieved by maximizing the rates of approach, entry, and passage through safe and desirable routes. Sometimes, however...
Authors
Theodore R. Castro-Santos, Russell W. Perry
Using mark-recapture models to estimate survival from telemetry data: Chapter 9.2 Using mark-recapture models to estimate survival from telemetry data: Chapter 9.2
Analyzing telemetry data within a mark–recapture framework is a powerful approach for estimating demographic parameters (e.g., survival and movement probabilities) that might otherwise be difficult to measure. Yet many studies using telemetry techniques focus on fish behavior and fail to recognize the potential of telemetry data to provide information about fish survival. The...
Authors
Russell W. Perry, Theodore R. Castro-Santos, Christopher M. Holbrook, Benjamin P. Sandford
Unintended consequences and trade-offs of fish passage Unintended consequences and trade-offs of fish passage
We synthesized evidence for unintended consequences and trade-offs associated with the passage of fishes. Provisioning of fish passageways at dams and dam removals are being carried out increasingly as resource managers seek ways to reduce fragmentation of migratory fish populations and restore biodiversity and nature-like ecosystem services in tributaries altered by dams. The benefits...
Authors
Robert L. McLaughlin, Eric R. Smyth, Theodore Castro-Santos, Michael L. Jones, Marten A. Koops, Thomas C. Pratt, Luis-Antonio Velez-Espino
Evaluation of nature-like and technical fishways for the passage of alewives at two coastal streams in New England Evaluation of nature-like and technical fishways for the passage of alewives at two coastal streams in New England
Nature-like fishways have been designed with the intent to reconnect river corridors and provide passage for all species occurring in a system. The approach is gaining popularity both in Europe and North America, but performance of these designs has not been quantitatively evaluated in a field setting for any North American species. Two nature-like fishways and three technical fishways...
Authors
Abigail E. Franklin, Alex Haro, Theodore R. Castro-Santos, John Noreika
Science and Products
Filter Total Items: 80
Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad
This paper describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon (N=75) and upstream migrating adult American shad (N=208). Controlled studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control...
Authors
Theodore R. Castro-Santos, Alex Haro
Passage of native riverine fishes through geometrically different sections of a vertical slot fishway on the Moselle River, Germany Passage of native riverine fishes through geometrically different sections of a vertical slot fishway on the Moselle River, Germany
In order to study effects of different geometric types of pools or change of the flow direction on the passability of fish, sets of PIT antennas were installed inside a modern vertical slot fishway at the mouth of the River Moselle. Fish of 13 abundant species were caught and tagged with PIT tags in 2013 and released in the tailwater of Koblenz. 16% of the tagged fish were detected...
Authors
Matthias Pitsch, Bernd Mockenhaupt, Theodore R. Castro-Santos
Basin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar) Basin-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...
Authors
Jaime Otero, Jan Henning L’Abee-Lund, Theodore Castro-Santos, Kjell Leonardsson, Geir O. Storvik, Bror Jonsson, J. Brian Dempson, Ian C. Russell, Arne J. Jensen, Jean-Luc Bagliniere, Mélanie Dionne, John D. Armstrong, Atso Romakkaniemi, Benjamin H. Letcher, John F. Kocik, Jaakko Erkinaro, Russell Poole, Ger Rogan, Hans Lundqvist, Julian C. MacLean, Erkki Jokikokko, Jo Vegar Arnekleiv, Richard J. Kennedy, Eero Niemela, 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, Oystein Skaala, Gordon W. Smith, Harald Saegrov, N. C. Stenseth, Leif Asbjørn Vøllestad
Posthandling survival and PIT tag retention by alewives—a comparison of gastric and surgical implants Posthandling survival and PIT tag retention by alewives—a comparison of gastric and surgical implants
We compared survival and tag retention of Alewives Alosa pseudoharengus tagged with PIT tags, using intraperitoneal (IP) surgical implants, gastric implants (GI), and untagged controls held for 38 d. Retention was 100% for IP-tagged Alewives and 98% for GI-tagged implants. No significant difference in survival was observed among any of these groups. These results lend support to the use...
Authors
Theodore Castro-Santos, Volney Voni
Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta)
Sprinting behavior of free-ranging fish has long been thought to exceed that of captive fish. Here we present data from wild-caught brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta), volitionally entering and sprinting against high-velocity flows in an open-channel flume. Performance of the two species was nearly identical, with the species attaining absolute speeds > 25...
Authors
Theodore Castro-Santos, Francisco Javier Sanz-Ronda, Jorge Ruiz-Legazpi
A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin
The majority of the fish passages built in the Neotropical region are characterised by low efficiency and high selectivity; in many cases, the benefits to fish populations are uncertain. Studies conducted in the Canal da Piracema at Itaipu dam on the Parana River indicate that the system component designated as the Discharge channel in the Bela Vista River (herein named Canal de deságue...
Authors
Theodore R. Castro-Santos, Helio Martins Fontes, Sergio Makrakis, Luiz Carlos Gomes, Joao Dirco Latini
Culverts in paved roads as suitable passages for neotropical fish species Culverts in paved roads as suitable passages for neotropical fish species
Improperly installed or poorly maintained culverts can pose a serious threat to fish by disrupting their habitat and endangering spawning success. Road culverts that are not designed for fish passage frequently can become obstacles. This can be especially problematic for migratory species, but can lead to fragmentation of resident populations as well. This study evaluated 40 culverts of...
Authors
Sergio Makrakis, Theodore R. Castro-Santos, Maristela Cavicchioli Makrakis, Ricardo Luiz Wagner, Mauricio Spagnolo Adames
Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent
This paper presents results of a fishway evaluation performed at the Engenheiro Sérgio Motta Hydroelectric Power Plant (known as Porto Primavera) - CESP, Paraná River, Brazil. The evaluation was designed to quantify entry and passage proportions of 4 long-distance migratory fish species: Brycon orbignyanus (piracanjuba), Piaractus mesopotamicus (pacu), Prochilodus lineatus (curimba), and
Authors
Ricardo Luiz Wagner, Sergio Makrakis, Theodore R. Castro-Santos, Maristela Cavicchioli Makrakis, Joao Henrique Pinheiro Dias, Rene Fuster Belmont
Time-to-event analysis as a framework for quantifying fish passage performance Time-to-event analysis as a framework for quantifying fish passage performance
Fish passage is the result of a sequence of processes, whereby fish must approach, enter, and pass a structure. Each of these processes takes time, and fishway performance is best quantified in terms of the rates at which each process is completed. Optimal performance is achieved by maximizing the rates of approach, entry, and passage through safe and desirable routes. Sometimes, however...
Authors
Theodore R. Castro-Santos, Russell W. Perry
Using mark-recapture models to estimate survival from telemetry data: Chapter 9.2 Using mark-recapture models to estimate survival from telemetry data: Chapter 9.2
Analyzing telemetry data within a mark–recapture framework is a powerful approach for estimating demographic parameters (e.g., survival and movement probabilities) that might otherwise be difficult to measure. Yet many studies using telemetry techniques focus on fish behavior and fail to recognize the potential of telemetry data to provide information about fish survival. The...
Authors
Russell W. Perry, Theodore R. Castro-Santos, Christopher M. Holbrook, Benjamin P. Sandford
Unintended consequences and trade-offs of fish passage Unintended consequences and trade-offs of fish passage
We synthesized evidence for unintended consequences and trade-offs associated with the passage of fishes. Provisioning of fish passageways at dams and dam removals are being carried out increasingly as resource managers seek ways to reduce fragmentation of migratory fish populations and restore biodiversity and nature-like ecosystem services in tributaries altered by dams. The benefits...
Authors
Robert L. McLaughlin, Eric R. Smyth, Theodore Castro-Santos, Michael L. Jones, Marten A. Koops, Thomas C. Pratt, Luis-Antonio Velez-Espino
Evaluation of nature-like and technical fishways for the passage of alewives at two coastal streams in New England Evaluation of nature-like and technical fishways for the passage of alewives at two coastal streams in New England
Nature-like fishways have been designed with the intent to reconnect river corridors and provide passage for all species occurring in a system. The approach is gaining popularity both in Europe and North America, but performance of these designs has not been quantitatively evaluated in a field setting for any North American species. Two nature-like fishways and three technical fishways...
Authors
Abigail E. Franklin, Alex Haro, Theodore R. Castro-Santos, John Noreika
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government