Endocrine disrupted fish in San Francisco Bay

Endocrine disrupted fish in San Francisco Bay


  • Collaborative study focuses on multiple sites located in San Francisco Bay
  • Pacific staghorn sculpin and Shiner perch being evaluated for chemical contaminants in their tissues
  • Fish show effects on important endocrine systems that regulates growth and development and can impair the overall health of the fish


San Francisco Bay

With collaborators at California State University-Long Beach, Moss
Landing Marine Laboratories and the San Francisco Estuary Institute, we
are participating in a large study on pollution impacts in wild fish living
within San Francisco Bay.  Locations within the Bay include the Southbay
region, inshore East Bay locations including Oakland Inner Harbor, San
Francisco and Berkeley waterfronts, and north into San Pablo Bay.  Sites
outside of the Bay (e.g., in remote, less populated areas) are used for
comparisons.  In this study, two marine fish species are being evaluated for
the levels of chemical contaminants in their tissues and the potential
physiological impacts of these contaminants in the animals.  Pacific staghorn
sculpin (Leptocottus armatus) and Shiner perch (Cymatogaster aggregata)
are common inshore fish in the Bay, and they are exposed to a large variety
of human-derived chemicals and deteriorated habitat.  Results from this
ongoing work have found that these fish have high concentrations of organic
contaminants in their tissues, such as polyaromatic hydrocarbons (PAHs),
polychlorinated biphenyls (PCBs), and pesticides.  These fish also show
significant effects in important endocrine systems, including the thyroid and
cortisol systems.  This is called “Endocrine Disruption” and it is of
significant concern since hormones regulate normal physiology in animals.
Impairment of the above endocrine systems can impair health (increased
disease or parasite susceptibility), growth and development, metabolism and
reproduction, among others.  These studies are the first of their kind being
carried out in San Francisco Bay, and they are helping us to understand the
how wildlife is being impacted by human by-products.  Continuing research
in this project is aimed at linking the different contaminants present in the
animals to the physiological effects and changes observed in the impacted



^ View of shorelines from Oakland’s Inner Harbor,
where shiner perch and staghorn sculpin live



^ Environmental scientists collecting fish samples
(for later laboratory analyses) at Santa Catalina
Island’s Pacific Ocean side. These samples serve
as a control reference group to compare with fish
from within more polluted loctions within San
Francisco Bay.  Other reference locations include
Tomales Bay and Bodega Bay, north of San



^ Shiner Surfperch (Cymalogaster Aggregata)



Support this Project!!!