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Theodore R Castro-Santos

Ted is a Research Ecologist Eastern Ecological Science Center in Kearneysville, WV.

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

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Sea lamprey

Fish locomotion and biomechanics as limiting and optimizing factors in fish passage

Swimming ability determines how well fish are able to access habitat, and is a fundamental design consideration for passing fish at dams, road crossings, etc. The purpose of this study plan is to improve understanding of how fish are able to negotiate zones of high velocity and turbulent flow, such as are found in fishways, culverts, as well as in natural areas. Swimming performance is limited by...
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Ecosystems, Energy and Minerals, Water Resources, Environmental Health Program, Fisheries Program, Invasive Species Program, Eastern Ecological Science Center
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Fish locomotion and biomechanics as limiting and optimizing factors in fish passage

Swimming ability determines how well fish are able to access habitat, and is a fundamental design consideration for passing fish at dams, road crossings, etc. The purpose of this study plan is to improve understanding of how fish are able to negotiate zones of high velocity and turbulent flow, such as are found in fishways, culverts, as well as in natural areas. Swimming performance is limited by...
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aquatic biomechanics

Fish Biomechanics

Biomechanics is the study of mechanical laws relating to the movement of living organisms. In regards to fish, biomechanics pertains to the body shape of different species and the various structures of fish muscles, fins, etc. The biomechanics of a fish impact its swimming performance which in turn affects its ability to surpass barriers to movement. Understanding the biomechanical drivers of...
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Ecosystems, Energy & Wildlife, Fisheries Program, Eastern Ecological Science Center
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Fish Biomechanics

Biomechanics is the study of mechanical laws relating to the movement of living organisms. In regards to fish, biomechanics pertains to the body shape of different species and the various structures of fish muscles, fins, etc. The biomechanics of a fish impact its swimming performance which in turn affects its ability to surpass barriers to movement. Understanding the biomechanical drivers of...
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USGS science for a changing world logo

A generic web application to visualize and understand movements of tagged animals

The goal of this project was to maximize the value of expensive animal tagging data. We developed an interactive web application to help scientists understand patterns in their own tagging datasets and to help scientists, funders and agencies communicate tagging data to decision-makers and to the general public. Interactive visualizations have emerged recently as a valuable tool for identifying pa
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Community for Data Integration (CDI)
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A generic web application to visualize and understand movements of tagged animals

The goal of this project was to maximize the value of expensive animal tagging data. We developed an interactive web application to help scientists understand patterns in their own tagging datasets and to help scientists, funders and agencies communicate tagging data to decision-makers and to the general public. Interactive visualizations have emerged recently as a valuable tool for identifying pa
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Filter Total Items: 36

The effects of horizontally and vertically oriented baffles on flow structure andascent performance of upstream-migrating fish

Considerable effort has been expended to construct culverts and fishways that allow for fish passage. However, the designs have seldom considered behaviour, energetics, and biomechanics of fish. In this study, we performed controlled experiments, in which upstreammigrating Alewife (Alosa pseudoharengus) and Brook Trout (Salvelinus fontinalis) were allowed to volitionally enter either one of two op
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Ecosystems, Eastern Ecological Science Center

Downstream migration and multiple dam passage by Atlantic Salmon smolts

The purpose of this study was to investigate behavior and survival of radio-tagged wild and hatchery-reared landlocked Atlantic Salmon Salmo salar smolts as they migrated past three hydropower dams equipped with fish bypass solutions in the Winooski River, Vermont. Among hatchery-reared smolts, those released early were more likely to initiate migration and did so after less delay than those relea
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Ecosystems, Eastern Ecological Science Center

Is motivation important to brook trout passage through culverts?

Culverts can restrict movement of stream-dwelling fish. Motivation to enter and ascend these structures is an essential precursor for successful passage. However, motivation is challenging to quantify. Here, we use attempt rate to assess motivation of 447 brook trout (Salvelinus fontinalis) entering three culverts under a range of hydraulic, environmental, and biological conditions. A passive inte
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Ecosystems, Eastern Ecological Science Center

Migratory behavior of adult sea lamprey and cumulative passage performance through four fishways

This article describes a study of PIT-tagged sea lamprey (Petromyzon marinus) ascending four fishways comprising three designs at two dams on the Connecticut River, USA. Migration between dams was rapid (median migration rate = 23 km·day−1). Movement through the fishways was much slower, however (median = 0.02–0.33 km·day−1). Overall delay at dams was substantial (median = 13.6–14.6 days); many fi
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Ecosystems, Energy & Wildlife, Eastern Ecological Science Center

Migratory delay leads to reduced passage success of Atlantic salmon smolts at a hydroelectric dam

Passage of fish through hydropower dams is associated with mortality, delay, increased energy expenditure and migratory failure for migrating fish and the need for remedial measures for both upstream and downstream migration is widely recognised. A functional fish passage must ensure safe and timely passage routes that a substantial portion of migrating fish will use. Passage solutions must addres
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Ecosystems, Energy & Wildlife, Eastern Ecological Science Center

Reinforcement and validation of the analyses and conclusions related to fishway evaluation data from Bunt et al.: ‘Performance of fish passage structures at upstream barriers to migration’

Detailed re-examination of the datasets that were used for a meta-analysis of fishway attraction and passage revealed a number of errors that we addressed and corrected. We subsequently re-analysed the revised dataset, and results showed no significant changes in the primary conclusions of the original study; for most species, effective performance cannot be assured for any fishway type.
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Ecosystems, Eastern Ecological Science Center

Analysis of brook trout spatial behavior during passage attempts in corrugated culverts using near-infrared illumination video imagery

We used video recording and near-infrared illumination to document the spatial behavior of brook trout of various sizes attempting to pass corrugated culverts under different hydraulic conditions. Semi-automated image analysis was used to digitize fish position at high temporal resolution inside the culvert, which allowed calculation of various spatial behavior metrics, including instantaneous gro
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Ecosystems, Eastern Ecological Science Center

Ascent ability of brown trout, <i>Salmo trutta</i>, and two Iberian cyprinids − Iberian barbel, <i>Luciobarbus bocagei</i>, and northern straight-mouth nase, <i>Pseudochondrostoma duriense</i> − in a vertical slot fishway

Passage performance of brown trout (Salmo trutta), Iberian barbel (Luciobarbus bocagei), and northern straight-mouth nase (Pseudochondrostoma duriense) was investigated in a vertical slot fishway in the Porma River (Duero River basin, Spain) using PIT telemetry. We analysed the effects of different fishway discharges on motivation and passage success. Both cyprinid species ascended the fishway eas
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Ecosystems, Eastern Ecological Science Center

Brook trout passage performance through culverts

Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and beh
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Ecosystems, Eastern Ecological Science Center

Sprinting performance of two Iberian fish: <i>Luciobarbus bocagei</i> and <i>Pseudochondrostoma duriense</i> in an open channel flume

This paper presents sprinting data from Iberian barbel (Luciobarbus bocagei) and northern straight-mouth nase (Pseudochondrostoma duriense), volitionally swimming against high velocity flows (1.5, 2.5 and 3 m s−1) in an open channel flume. Swimming endurance and speed greatly exceeded previously published observations with both species attaining swim speeds >20 body lengths s−1. Flow velocity was
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Ecosystems, Eastern Ecological Science Center

Accelerometer-derived activity correlates with volitional swimming speed in lake sturgeon (Acipenser fulvescens)

Quantifying fine-scale locomotor behaviours associated with different activities is challenging for free-swimming fish.Biologging and biotelemetry tools can help address this problem. An open channel flume was used to generate volitionalswimming speed (Us) estimates of cultured lake sturgeon (Acipenser fulvescens Rafinesque, 1817) and these were paired withsimultaneously recorded accelerometer-der
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Ecosystems, Energy & Wildlife, Eastern Ecological Science Center

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. No injuries
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Ecosystems, Energy & Wildlife, Eastern Ecological Science Center

Pre-USGS Publications

Bunt, C.M., Castro-Santos, T., Haro, A. Reinforcement and Validation of the Analyses and Conclusions Related to Fishway Evaluation Data from Bunt et al.: ‘Performance of Fish Passage Structures at Upstream Barriers to Migration (2016) River Research and Applications, 32 (10), pp. 2125-2137.
Sanz-Ronda, F.J., Bravo-Córdoba, F.J., Fuentes-Pérez, J.F., Castro-Santos, T. Ascent ability of brown trout, Salmo trutta, and two Iberian cyprinids - Iberian barbel, Luciobarbus bocagei, and northern straight-mouth nase, Pseudochondrostoma duriense - In a vertical slot fishway (2016) Knowledge and Management of Aquatic Ecosystems, 2016-January (417),
Sanz-Ronda, F.J., Ruiz-Legazpi, J., Bravo-Córdoba, F.J., Makrakis, S., Castro-Santos, T. Sprinting performance of two Iberian fish: Luciobarbus bocagei and Pseudochondrostoma duriense in an open channel flume (2015) Ecological Engineering, 83, pp. 61-70.
Goerig, E., Castro-Santos, T., Bergeron, N.É. Brook trout passage performance through culverts (2015) Canadian Journal of Fisheries and Aquatic Sciences, 73 (1), pp. 94-104.
Thiem, J.D., Dawson, J.W., Gleiss, A.C., Martins, E.G., Haro, A., Castro-Santos, T., Danylchuk, A.J., Wilson, R.P., Cooke, S.J. Accelerometer-derived activity correlates with volitional swimming speed in lake sturgeon (Acipenser fulvescens) (2015) Canadian Journal of Zoology, 93 (8), pp. 645-654.

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