Skip to main content
U.S. flag

An official website of the United States government

Laboratory Investigations with Fish Species to Assist with Implementing Barataria-Terrebonne National Estuary Program’s Ecological Management Action Plans

Active
By Wetland and Aquatic Research Center August 1, 2024

WARC scientists will obtain live fish specimens from the field to conduct and enhance on-going laboratory research on harmful algal blooms and the use of piscicides to control invasive fish. 

Estuarine site for a possible harmful algal bloom in Wilkinson Bayou Cutoff
Sources/Usage: Public Domain. View Media Details
Figure 1a. An estuarine site for a possible harmful algal bloom at Wilkinson Bayou Cutoff.
A map showing the location of the Wilkinson Bayou Cutoff north of Wilkinson Bay, Louisiana
Sources/Usage: Public Domain. View Media Details
Figure 1b. Location of Wilkinson Bayou Cutoff north of Wilkinson Bay, Louisiana.

The Science Issue and Relevance: This project addresses two ecological management action plans described in the Barataria-Terrebonne National Estuary Program (BTNEP) Comprehensive Conservation Management Plan and enhances ongoing USGS Wetland and Aquatic Research Center (WARC) and Lower Mississippi-Gulf Water Science Center (LMGWSC) research efforts in harmful algal blooms (HAB) and invasive carp. Cyanobacteria blooms pose risks to human and animal health and ecosystem sustainability around the world. Some blooms produce toxins that can lead to illness or mortality when animals and humans are exposed; such blooms are referred to as harmful algal blooms. WARC lab investigations into HAB-induced biomarkers of exposure and effect in fish and mammals is on-going. In addition, the use of a piscicide in ecosystems is a reasonable method to remove invasive carp species such as Bighead Carp (Hypophthalmichthys nobilis) and Silver Carp (Hypophthalmichthys molitrix). Antimycin A, produced by the bacteria (Streptomyces) and formerly commercially available in a formulation, is a focus of investigation for the influence of this active ingredient on cellular targets of invasive carp and non-target fishes. The goal for this project is to obtain live fish specimens from the field to conduct and enhance on-going laboratory research that includes: (1) algal and cyanobacterial blooms influencing fish in freshwater and estuarine ecosystems, and (2) the use of piscicides in fish communities for the control of invasive fish, especially invasive carp. 

LADWF staff pull fish from a gill net on a boat on the Red River
Sources/Usage: Public Domain. View Media Details
Figure 2a. Louisiana Department of Wildlife and Fisheries on Red River, LA catching fish in gill nets.
Channel Catfish in WARC laboratory available for bleeding
Sources/Usage: Public Domain. View Media Details
Figure 2b. Channel Catfish in WARC laboratory available for bleeding
WARC SSC fish for Channel Catfish at the Vermillion River in Lafayette, Louisiana
Sources/Usage: Public Domain. View Media Details
Figure 2c. WARC Student Services Contractor fishing for Channel Catfish at the Vermillion River in Lafayette, Louisiana.
Lydia Duhon in WARC laboratory holding syringe containing blood from a channel catfish
Sources/Usage: Public Domain. View Media Details
Figure 2d. WARC Student Services Contractor holding a syringe containing fish blood.

Methodology for Addressing the Issue: Fish community samples from the field are necessary for obtaining cells from tissues to test the two on-going hypotheses regarding HABs. One site in the estuary, Wilkinson Bayou Cutoff (Fig. 1), is a potential focal area for blooms and has been monitored for water quality and HAB activity. Fish can be sampled on site and compared to water quality results relating the HAB abundance and toxin production (i.e., chlorophyll a, phycocyanin, and microcystins). WARC’s initial laboratory focus is on Channel Catfish (Ictalurus punctatus) and Grass Carp (Ctenopharyngodon idella). Catfish blood is obtained from fish collected from Louisiana waters and WARC’s wet lab (Fig. 2). The Grass Carp are certified triploids (Fig. 3) obtained by permit from a hatchery vendor.

Future Steps: 

  1. USGS WARC scientists have delineated the sublethal effects of a controlled HAB toxin (microcystin-LR) in mallard ducks (Anas platyrhyncos). They will investigate MC-LR effects in murine cell culture (human surrogate model), and will test an ingestible compound to proactively inhibit the toxin’s mode of action. WARC scientists are poised for accepting field-collected avian livers for testing sublethal effects.
  2. USGS WARC scientists will continue to collaborate with USGS Columbia Environmental Research Center in testing this active ingredient (ANT-A) and other potential chemicals against cellular targets in invasive carp to guide management options for controlling invasive carp species in aquatic ecosystems of concern. The information can be used by partner state and Department of the Interior agencies to help guide their management strategies.
LDWF staff hold a Grass Carp with a net on a boat in the Red River
Sources/Usage: Public Domain. View Media Details
Figure 3a. LADWF with Grass Carp on the Red River.
WARC scientist sits on a dock on the Red River with a syringe preparing to collect blood from a Grass Carp
Sources/Usage: Public Domain. View Media Details
Figure 3b. WARC personnel bleeding a Grass Carp.
LADWF staff member holds a Silver Carp in a net on a boat on the Red River
Sources/Usage: Public Domain. View Media Details
Figure 3c. Louisiana Department of Wildlife and Fisheries on Red River with a Silver Carp.
Certified triploid Grass Carp at Keo Fish Farm, Keo, Arkansas
Sources/Usage: Public Domain. View Media Details
Figure 3d. Certified triploid Grass Carp at Keo Fish Farm, Keo, Arkansas.

Louisiana Department of Wildlife and Fisheries

WARC scientists will obtain live fish specimens from the field to conduct and enhance on-going laboratory research on harmful algal blooms and the use of piscicides to control invasive fish. 

Estuarine site for a possible harmful algal bloom in Wilkinson Bayou Cutoff
Sources/Usage: Public Domain. View Media Details
Figure 1a. An estuarine site for a possible harmful algal bloom at Wilkinson Bayou Cutoff.
A map showing the location of the Wilkinson Bayou Cutoff north of Wilkinson Bay, Louisiana
Sources/Usage: Public Domain. View Media Details
Figure 1b. Location of Wilkinson Bayou Cutoff north of Wilkinson Bay, Louisiana.

The Science Issue and Relevance: This project addresses two ecological management action plans described in the Barataria-Terrebonne National Estuary Program (BTNEP) Comprehensive Conservation Management Plan and enhances ongoing USGS Wetland and Aquatic Research Center (WARC) and Lower Mississippi-Gulf Water Science Center (LMGWSC) research efforts in harmful algal blooms (HAB) and invasive carp. Cyanobacteria blooms pose risks to human and animal health and ecosystem sustainability around the world. Some blooms produce toxins that can lead to illness or mortality when animals and humans are exposed; such blooms are referred to as harmful algal blooms. WARC lab investigations into HAB-induced biomarkers of exposure and effect in fish and mammals is on-going. In addition, the use of a piscicide in ecosystems is a reasonable method to remove invasive carp species such as Bighead Carp (Hypophthalmichthys nobilis) and Silver Carp (Hypophthalmichthys molitrix). Antimycin A, produced by the bacteria (Streptomyces) and formerly commercially available in a formulation, is a focus of investigation for the influence of this active ingredient on cellular targets of invasive carp and non-target fishes. The goal for this project is to obtain live fish specimens from the field to conduct and enhance on-going laboratory research that includes: (1) algal and cyanobacterial blooms influencing fish in freshwater and estuarine ecosystems, and (2) the use of piscicides in fish communities for the control of invasive fish, especially invasive carp. 

LADWF staff pull fish from a gill net on a boat on the Red River
Sources/Usage: Public Domain. View Media Details
Figure 2a. Louisiana Department of Wildlife and Fisheries on Red River, LA catching fish in gill nets.
Channel Catfish in WARC laboratory available for bleeding
Sources/Usage: Public Domain. View Media Details
Figure 2b. Channel Catfish in WARC laboratory available for bleeding
WARC SSC fish for Channel Catfish at the Vermillion River in Lafayette, Louisiana
Sources/Usage: Public Domain. View Media Details
Figure 2c. WARC Student Services Contractor fishing for Channel Catfish at the Vermillion River in Lafayette, Louisiana.
Lydia Duhon in WARC laboratory holding syringe containing blood from a channel catfish
Sources/Usage: Public Domain. View Media Details
Figure 2d. WARC Student Services Contractor holding a syringe containing fish blood.

Methodology for Addressing the Issue: Fish community samples from the field are necessary for obtaining cells from tissues to test the two on-going hypotheses regarding HABs. One site in the estuary, Wilkinson Bayou Cutoff (Fig. 1), is a potential focal area for blooms and has been monitored for water quality and HAB activity. Fish can be sampled on site and compared to water quality results relating the HAB abundance and toxin production (i.e., chlorophyll a, phycocyanin, and microcystins). WARC’s initial laboratory focus is on Channel Catfish (Ictalurus punctatus) and Grass Carp (Ctenopharyngodon idella). Catfish blood is obtained from fish collected from Louisiana waters and WARC’s wet lab (Fig. 2). The Grass Carp are certified triploids (Fig. 3) obtained by permit from a hatchery vendor.

Future Steps: 

  1. USGS WARC scientists have delineated the sublethal effects of a controlled HAB toxin (microcystin-LR) in mallard ducks (Anas platyrhyncos). They will investigate MC-LR effects in murine cell culture (human surrogate model), and will test an ingestible compound to proactively inhibit the toxin’s mode of action. WARC scientists are poised for accepting field-collected avian livers for testing sublethal effects.
  2. USGS WARC scientists will continue to collaborate with USGS Columbia Environmental Research Center in testing this active ingredient (ANT-A) and other potential chemicals against cellular targets in invasive carp to guide management options for controlling invasive carp species in aquatic ecosystems of concern. The information can be used by partner state and Department of the Interior agencies to help guide their management strategies.
LDWF staff hold a Grass Carp with a net on a boat in the Red River
Sources/Usage: Public Domain. View Media Details
Figure 3a. LADWF with Grass Carp on the Red River.
WARC scientist sits on a dock on the Red River with a syringe preparing to collect blood from a Grass Carp
Sources/Usage: Public Domain. View Media Details
Figure 3b. WARC personnel bleeding a Grass Carp.
LADWF staff member holds a Silver Carp in a net on a boat on the Red River
Sources/Usage: Public Domain. View Media Details
Figure 3c. Louisiana Department of Wildlife and Fisheries on Red River with a Silver Carp.
Certified triploid Grass Carp at Keo Fish Farm, Keo, Arkansas
Sources/Usage: Public Domain. View Media Details
Figure 3d. Certified triploid Grass Carp at Keo Fish Farm, Keo, Arkansas.

Louisiana Department of Wildlife and Fisheries