A Pilot Study of the Effects of Contaminants on Shiner Surf Perch in the San Francisco Bay-Estuary An update-November 22, 2005. Robert Spies, AMS Kathrine Springman, UC Davis Spring 2005. Problem. Populations of many fish in the SF Estuary are in a long-term decline.
A Pilot Study of the Effects of Contaminants on Shiner Surf Perch in the San Francisco Bay-EstuaryAn update-November 22, 2005
Robert Spies, AMS
Kathrine Springman, UC Davis
Conceptual model for shiner surf perch declines
sewage, street runoff,
atmospheric sources, et.c
Determine if shiner surfperch (Cymatogaster aggregata; Embiotocidae) show effects of contamination on some aspect of their fitness, growth or reproduction.
1.Collect POCIS/SPMD samples for confirmation of 2006 sampling site selection.
2. Chemical analyses of POCIS/SPMD contents.
3. If surfperch present sample and test blood of males for ZRPs.
SPMD : Remove biofoulants
Dialysate: Concentration, GPC cleanup
Extract: Chemical analysis
(e.g. GC/MS, GC/ECD)
The Problem The relative binding capacity of synthetic chemicals to hormone receptors may be 1/100 to 1/1000 of that of the natural ligand (e.g., estrogen) and the chemical concentration may exceed the effective concentration by 100 to 10,000 X.
The Problem:there are numerous and complex endocrine interactions in reproduction and growth of fishes(sensory input-endocrine cascades--feedback loops)
Agonist for gonadotropin Iacceleration of gametogenesis
Acceleration of oogenesis in kelp bass
dosed with DDT and PCB
Reproductive success in relationship to a biomarker of contaminant exposure
(4-36 young annually) can be determined
in early spring and summer.
1. Starry flounder reproductive dysfunction linked to P4501A and PCBs (Spies & Rice, 1988).
2. Sex reversal and estrogenic effects in longjaw mud suckers (Cherr et al., unpubl.).
3. Chinook salmon in upper watershed show high proportions of females that are phenotypically male (Williamson and May, 2002).
3. Striped bass larval growth and histology negatively affected (Ostrach, unpubl.).
4. Speckeld sanddab histology (Spies et al., 1993; Gunther et al. 1997).
5. Herring egg abnormal development (Vines et al., 2000).