Transcript NTAA_NTF Presentation_MattHudson_060408am.ppt

Reducing Risks to the Anishinaabe
from Methylmercury
GLIFWC’s Mercury Program
Matt Hudson
Environmental Biologist
Great Lakes Indian Fish and Wildlife Commission (GLIFWC)
GLIFWC Mission
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Assist member bands in the implementation
of off-reservation harvest seasons
Protect treaty rights and natural resources
GLIFWC provides
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natural resource management expertise
conservation enforcement
legal and policy analysis
public information services
Tribal Walleye Harvesting
Netting
Spearing
Inland Lake Walleye Harvest – 1837
and 1842 Ceded Territory
Mercury and fish consumption
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Major route for human exposure to mercury
Algae
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Zooplankton
Fish
People
Walleye top predator fish that often contain
elevated levels of mercury
Mercury and fish consumption
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Fish is a healthy and culturally important
food source
Other available consumption advisories
don’t typically consider cultural aspects of
fish consumption
Challenge is maximizing health and
cultural benefits while minimizing risks
GLIFWC’s Mercury Program Goal
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To develop, implement, evaluate, and
document a comprehensive, systematic,
and culturally-sensitive intervention
program to reduce risks associated with
subsistence based consumption of
methylmercury contaminated fish.
GLIFWC’s Mercury Program
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Main Focus
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Mercury data collection (since 1989)
Outreach through consumption advisory maps (since
1996)
In Addition – Collect information to inform and
improve consumption advisory process
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Fish consumption study
Science-based advisory methodology
Targeted intervention
Evaluate intervention
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Number of Walleye Samples
Walleye Samples Collected by GLIFWC for
Mercury Testing by Year (Inland Lakes)
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Walleye Advisory Maps
Walleye Consumption by GLIFWCMember Tribes
Intervention Program
Focus
 Fish Harvesters
 WI Women of Childbearing Age and Children
Approach
 Tribal Leaders
 GLIFWC Wardens
 Elders
 Broad Dissemination of Maps
Evaluate effectiveness
 Pre-intervention surveys
 Post-intervention surveys
How Effective Was Our
Intervention?
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Awareness of maps increased in all
surveyed groups
Concern about mercury in fish increased
Preference for smaller walleye increased
Harvesters were labeling fillet bags with
lake name
Few using maps to choose lakes for
harvest
Tribal lifeways not affected by advisory
program
Other Ways We are Using
Mercury Program Data
Mercury Concentrations in Walleye
in Northern WI Declining Over Time
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Mercury (μg/g) .
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Male Skin-Off Fillets
Male Skin-On Fillets
Female Skin-Off Fillets
Female Skin-On Fillets
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Fine dotted lines give bounds that have a 95%
probability of containing the regional trend lines
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1981
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1987
1989
1991
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Year
1995
1997
1999
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2003
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Estimating Mercury Exposure to
Tribal Fish Harvesters
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Probabalistic Risk Assessment – Lifeline
Software
Mercury Exposure Risk Analysis
Harvest Data
Mercury Data
Consumption Data
Acknowledgements
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Adam DeWeese, Former Environmental
Biologist, GLIFWC
Neil Kmiecik, Biological Services Director,
GLIWFC
Jeffery Foran, Ph.D., EHSI LLC
ATSDR and EPA for funding