Development of Pacific Herring Embryo and Larval Bioassays
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- Alexandra Garrison
- 5 years ago
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1 Development of Pacific Herring Embryo and Larval Bioassays Paul Dinnel Randall Marshall Douglas Middaugh Karen Bergmann James Elphick Western Washington University, WA Department of Ecology, US EPA (retired), Nautilus Environmental
2 Pacific herring. an important forage fish Range: San Francisco to Alaska Spawning: Nearshore aquatic vegetation Forage fish for: Salmon & marine fish Marine birds Marine mammals Humans (food & bait)
3 Population and Fishery Trends Cherry Point, Washington Biomass, Tons Spawning biomass Fishery landings Year
4 Are Industrial Effluents Part of the Problem? Effluents now tested with EPA-approved tests Rainbow trout Sea urchin or mollusk embryos Juvenile top smelt survival & growth test Top smelt Not native to Washington As sensitive as larval herring?
5 Project Goals Develop herring embryo and larval test protocols Compare sensitivity to EPA approved tests Assess variability of herring tests Validate & export each protocol for routine use
6 Test Development Herring sources & availability Test format Exposure times, solution changes Temperature Salinity, including brines & artificial sea salts Dissolved oxygen & ph Light intensity & quality Photoperiod Food type and quantity Test endpoints Test success criteria Test result variability
7 Test Organism Sources Spawn on Eelgrass/Algae Excised Gonads Available January - June
8 Embryo Test 15 Day test; hatching begins ~ Day 10 Incubation: 12 ºC, variable salinity, dim light Add ~100 eggs to Petri dish in 30 ml solution Remove unfertilized eggs at Day 1-2, keeping ~20 eggs Solution changes of 100% at 1-2 day intervals Heart beat/movement counts at ~Day 6 Successful test = 70% control normal survival
9 Embryo Test Test endpoints. Normal survival at hatch Length at hatch Heart rate
10 Larval Tests 4-day Acute Survival 10-day Survival & Growth Survival Dry weight or Biomass
11 Larval Survival & Growth Test 10 day test with feeding fish Start with fish, cull to 10 feeding fish at Day ml volumes in 400 ml beakers Incubation: 12 ºC, variable salinity, 16:8 L:D photoperiod, ~1,000 lux, feed Artemia daily Solution changes of 75% at 1-2 day intervals Successful test = 80% control survival, 30% growth
12 Larval Food Natural food mostly copepods, but. Foods tested: Rotifers Artemia nauplii Decapsulated Artemia cysts Otohime micropellets Copepods Tigriopus californicus Acartia tonsa Sea urchin larvae Best food so far = Artemia nauplii
13 Toxicants Tested Reference toxicants Potassium chloride (KCl) Sodium dodecyl sulfate (SDS) Copper (Cu) Creosote leachate Sewage spiked with KCl, SDS and Copper This year Industrial effluents Cherry Point ambient seawater near discharges
14 Relative Sensitivity Potassium Chloride RB Trout Acute RB Trout Embryo Silverside Acute LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival KCl Concentration, mg/liter
15 Relative Sensitivity Potassium Chloride RB Trout Acute RB Trout Embryo Silverside Acute LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival = > values KCl Concentration, mg/liter
16 Sodium Dodecyl Sulfate RB Trout Acute RB Trout Embryo Silverside Acute LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival SDS Concentration, mg/liter
17 Copper RB Trout Acute RB Trout Embryo Silverside Acute LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival Copper Concentration, ug/liter
18 Creosote Leachate ~ 300 chemicals ~ 60% PAHs RB Trout Acute RB Trout Embryo Not tested Not tested Silverside Acute LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival Creosote, %
19 Spiked Sewage Effluent RB Trout Acute RB Trout Embryo Silverside Acute Not tested LC50 or EC50 Top Smelt 7-Day Survival Sea Urchin 10 Day Biomass, IC25 10-Day Survival 4-Day Acute Embryo Survival = > values Sewage Concentration, %
20 Sensitivity No one test is most sensitive all of the time Herring tests most sensitive to KCl and PAH-laden creosote solutions Test Variability Meets the recommendations of the WA Biomonitoring Science Advisory Board (1994) and the Herring Settlement Agreement (CVs <60%)
21 Best Bioassay Scenario Screening test Acute larval test Survival Definitive tests Embryo Normal survival Larval length at hatch Survival & Growth Survival Dry Weight or Biomass
22 Thank you! Kurt Stick & Crew, WDFW Paul Hershberger & Crew, USGS Fred Griffin, Carol Vines, Gary Cherr, UC Davis ODFW DFO, Nanaimo, BC ADFG SE and Kodiak regions Bill Stubblefield, Parametrix Research Assistants Nate Schwarck Heather Farren Rick Haley Rich Hoover Undergraduate students & NSF MIMSUP Program Funding from: WDOE Texaco Restoration Fund U.S. EPA Industry
23 Questions?