Text Size: A  A  A

Videos

Bay 101: Intersex Fish



November 20, 2014

Fish biologist Vicki Blazer with the U.S. Geological Survey (USGS) brings her team to the Shenandoah River in Front Royal, Va., to collect and study smallmouth bass, a species in which intersex characteristics have been linked to chemical contaminants in the Chesapeake Bay region.

Intersex conditions occur when exposure to chemicals disrupts the hormonal systems of an animal, leading to the presence of both male and female characteristics in an animal that should exhibit the characteristics of just one sex in its lifetime. In the case of smallmouth bass, male intersex fish are found with immature eggs in their testes, which indicates exposure to estrogenic and anti-androgenic chemicals.

“The sources of estrogenic chemicals are most likely complex mixtures from both agricultural sources, such as animal wastes, pesticides and herbicides, and human sources from waste water treatment plant effluent and other sewage discharges,” says Blazer, who first discovered intersex characteristics in fish while studying fish kills in the South Branch of the Potomac River and the Shenandoah River.

Produced by Will Parson
Music: “A Moment of Jazz” by Ancelin

Related Videos

  • Bay 101: Intersex Fish
  • Bay 101: Sediment
  • Bay 101: Ospreys
  • PSA: What does it take to restore and protect the Chesapeake Bay?
  • Bay 101: Air Pollution
  • From the Field: Winter dredge survey counts Chesapeake Bay crabs
  • Bay 101: Striped Bass
  • From the Field: Monitoring water quality in the Chesapeake Bay
  • From the Field: Sustainable agriculture in Lancaster County, Pa.
  • Bay 101: Fish Kills
  • Bay 101: American Shad
  • Bay 101: Algae Blooms

Comments:


Post A Comment:

410 Severn Avenue / Suite 112
Annapolis, Maryland 21403
Tel: (800) YOUR-BAY / Fax: (410) 267-5777
Directions to the Bay Program Office
Terms of Use | Privacy Policy
©2012 Chesapeake Bay Program | All Rights Reserved