Mercury in Waterfowl (Consumption Advisory)

Transcription

1 Mercury in Waterfowl (Consumption Advisory) Photo courtesy R. Mosley Josh Vest Utah State Univ. Michael Conover Utah State Univ. Clay Perschon Utah DWR John Luft Utah DWR

2 BACKGROUND 2003 USGS finds Hg levels in GSL water Among highest ever measured, 25X higher than levels in FL 2005 USGS finds elevated Hg in brine shrimp, grebe livers from GSL

3 Utah Fish Advisories Photo courtesy R. Mosley 2005 Utah becomes 47 th state to issue Hg health advisory for eating fish

4 Duck Migration Corridors 3-5 Million Ducks to Utah Annually Derived from Alaska, NWT, Western Canadian Provinces, Adjacent States Winter in Calif., W. Mexico, Gulf Coast, Central America

5 How do Contaminants Influence Ducks?

6 Hg IMPACTS to BIRDS ADULTS Decreased Nesting Effort Increased Nest Abandonment Decreased Survival Rates Direct Mortality YOUNG Teratogenic/Mutagenic No eyes, brain outside skull, malformed appendages Decreased Growth rates

7 Hg IMPACTS to HUMANS Impacts nervous system development and function Organ and tissue growth Brain development and function Particular concern to pregnant women and children

8 People Eat Ducks Too OBJECTIVES Waterfowl hunters request and DWR agrees to test ducks Potential Human Health Concerns Influence of contaminants on ducks Influence of contaminants on other waterbirds Photo:farrbetterhunting.net

9 Initial Hg Tissue Samples Archived samples GWT, SHOV, GOLD Collected Winter 2004, food habitat study Collected mostly from GSL South Armbrine Represent worst case scenario Prioritize testing Tested edible tissue (skin, breast muscle)

10 Muscle Concentrations Mercury Breast Muscle Tissue 5 MERCURY 4 Hg_Muscle (ppm, ww) n = 20 n = 20 n = 20 COGO NSHO AGWT

11 Other Published Hg Studies GWT SHOV GOLD GSL NEVADA MANITOBA IOWA.06.14??

12 Mean Hg Levels (ppm) GWT SHOV GOLD Muscle Skin

13 Hg HUMAN HEALTH SCREENING LEVELS IN FOOD FDA (Regulates Commercial Food Commodities) eg Tuna, Beef, Chicken 1 ppm EPA (Standards for Fish and Wildlife).3 ppm Utah Department of Health uses EPA Standard Other State Health Departments use FDA Standards

14 Mean Hg Levels (ppm) GWT SHOV GOLD Muscle Skin

15 Waterbirds Check other species Cross-roads of the West > 70 Waterbird Species > 1 million Waterbirds present in early Fall

16 Next Phase of Collections UDWR greatly expanded marsh duck collections 10 spp. Increase GSL sample sizes Other Contaminants Temporal and Spatial Variation Late-Winter/Early-Spring Different Bays Sample Invertebrates Hg Concentration (ppm,ww) in Breast Muscle Tissue n = 10 n = 10 n = 10 n = 11 n = 10 MALL NOPI AGWT GADW RUDU Species

17 2004 Winter Mercury Sampling Gad Cinn. Pintail Mall Gold GWT Shoveler Ruddy Redhead Scaup

18 UTAH HEALTH ADVISORY DOH, DWR, DEQ jointly issued advisory to not shoot or eat NSHO and COGO Issued 2 days before the duck season, posted advisories First health advisory for consuming waterfowl in North America Unique as do not eat rather than frequency of meals Created consideration of closed season on these species due to wasting rules

19 Shoveler harvest increased 10% on opening weekend!

20 2005 Summer Mercury Sampling Gad Cinn. Pintail Mall Gold GWT Shoveler Ruddy Redhead Scaup

21 Monthly GSL Duck Populations Average 800, , , , , , , ,000 0 JULY SEPT NOV JAN MAR MAY Recreated from Aldrich and Paul (2002)

22 2005 Fall Mercury Sampling Gad Cinn. Pintail Mall Gold GWT Shoveler Ruddy Redhead Scaup

23 2005 Summer-Fall Mercury Comparisons Shoveler GWT Gold Mall Pintail Cinn. Gad Ruddy Redhead Scaup Summer 2005 Fall 2005

24 Conclusions Continued Monitoring Some GSL Contaminants Elevated or at Harmful Effect Levels Human Consumption of COGO, NSHO & CITE should be limited Determine if Contaminant Levels May be Correlated with Physiological Condition GSL Water Quality Standards Needed Hg in GSL likely not new

25 Questions?

26 Photo courtesy R. Mosley