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: 82
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
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
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
Science and Products
Filter Total Items: 82
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
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
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
*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