Restoring Aquatic Connectivity in the Great Lakes Basin The Contaminants Issue

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1 Restoring Aquatic Connectivity in the Great Lakes Basin The Contaminants Issue USFWS Green Bay Field Office Environmental Contaminants Program Sarah Warner

2 Case Study: The Menominee River Menominee, MI Marinette, WI

3 80 miles 51 miles 23 miles 1 mile

4 Menominee River Fish Passage Project Stage 1

5 Park Mill Dam Menominee Dam

6 Lake Sturgeon (Acipenser fulvescens) Top of the food chain consumer Long lived 82 years in Lake Winnebago! Reproductive age for female 25 years Do not die after spawning Most swim downstream after spawning Sensitive to contaminants Known to carry high burdens of contaminants What are the concentrations of contaminants in Menominee River sturgeon?

7 PCB (µg/g ww) in Fish Tissues Conversion 2.5 Concentrations of total PCBs in Fish Tissues (n=126). Section 0 has 5.8 times the concentrations in fish tissues compared to all other sections of the river. 6 5 Concentrations of PCBs in Fish Tissues at Sections of the Memominee River WI Section of River Section 0 (fish below the Menominee Dam in Green Bay waters) Section 1 (fish between the Park Mill Dam and the Grand Rapids Dam) Section 2 (fish between the Grand Rapids Dam and the White Rapids Dam) Section 3 (fish between the Chalk Hill Dam and the Sturgeon Falls Dam) Section 4 (fish above the Sturgeon Falls Dam)

8 Concentrations of Total PCBs in Fish Tissues (n=21). Sturgeon below the Menominee Dam have 6.3 times the concentrations compared to sturgeon above. Below Above

9 Screening Level Risk Assessment - Calculated Risk by Using Bald Eagles as Bioindicator Species Bald Eagles as indicator species for piscivorous species Bald Eagles uptake PCBs via food (fish) Female depurates PCBs into yolk and albumen of egg 0.1 ppm PCB 77 - American Kestrel skeleton with incomplete ossification of sacral/caudal vertebrae and beak defect (Hoffman et al. 2009)

10 Risk Analysis Ecological risk can be estimated numerically using the Hazard Quotient (HQ) approach. The HQ is a ratio, which can be used to estimate if risk is likely or not due to the contaminant in question. HQ = [concentration of contaminant in eagle diet (µg/g)] * BMF] bald eagle egg NOAEC (µg/g) HQ > 1.0 : Harmful effects are LIKELY due to the contaminant in question HQ = 1.0: The contaminant alone is NOT likely to cause harmful effects HQ < 1.0: Harmful effects are NOT likely

11 Although there is risk to bald eagles, and the risk increases up to 40% with the addition of downstream sturgeon to the upstream ecosystem, the risk is likely to be below levels associated with loss of eagle productivity.

12 0.5 ppm total PCBs in fathead minnows reduced fecundity (Adams et al. 1992) 0.31 ppm total PCBs striped bass reduced larval survival (Westin et al. 1985)

13 PCBs in Sturgeon Eggs One female sturgeon can produce millions of eggs! What are the concentrations in the eggs? Are concentrations at levels that reduce egg hatchability or development? Will organisms that feed on eggs (such as other fish species) be adversely affected by concentrations in those eggs? 0.4 ppm PCB 126/g egg = concentration that caused yolk sac and pericardial edema, hemorrhaging of eyes and head, shortened maxillaries, and delayed development to shovelnose sturgeon eggs (Papoulias and Coffey et al. 2003)

14 Moving Other Species Upstream Species that die upstream can increase the exposure and risk to piscivorous wildlife. What is the additive risk of PCBs in eggs millions of eggs (PCB doses) in the system? PCB loading into the cleaner upstream ecosystem. Increased fish consumption advisories? Common Carp 8.81 ppm below, 0.70 ppm above Walleye 1.82 ppm below, 0.36 ppm above 2.53 ppm below, 0.29 above Northern Pike

15 Steps for Practitioners Is the river clean where dam removal or passage project is to take place? Fish consumption advisories AOC area Clean Water Act 303 (d) List of Impaired Waters If system is contaminated, work with the local FWS biologists to determine the extent of risk and implications to species upstream. Establish criteria (ranking system) for fish passage projects.

16 Steps for Practitioners Only create fish passage above the lowermost dam to reconnect fish in the cleaner system. Monitor the health of the system whole fish and egg contaminant studies; for piscivorous birds, egg contaminant studies. Steps for Funding Agencies In reviewing or funding fish passage proposals, make sure the contaminants issue is addressed. Contaminant testing and risk assessments can be a part of all fish passage projects. Funding for contaminant testing written in the proposal.

17 Our mission: working with others, to conserve, protect and enhance fish, wildlife, and plants and their habitats. Is our action to restore a watershed and to connect a river unintentionally degrading the ecosystem, putting the species we are trying to protect at risk? Risks versus benefits? Risk assessments and research can help determine level of risk to wildlife in the upstream system from fish passage projects.