Lead and Wildlife. Julie A. Blanchong Department of Natural Resource Ecology and Management Iowa State University

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1 Lead and Wildlife Julie A. Blanchong Department of Natural Resource Ecology and Management Iowa State University

2 Lead Negative impacts of lead on human health have become well-known through: Food contamination in cans sealed with lead Lead-based paints and glazes Leaded gasoline Lead in drinking water which passes through lead pipes connected Solder Shutterstock Recently, the toxic effects of lead ingested by wildlife have gained attention

3 Issue: Threat of lead ammunition to wildlife Know: Lead can harm individuals (including humans) Debate: Degree to which lead ammunition and fishing tackle are threats to viability of wildlife populations

4 What is lead (Pb)? Naturally occurring element Soft, blue-gray metal Very stable No known biological function 2 forms Organic- occupational, leaded gasoline Inorganic- paint, storage batteries, ammunition, sinkers Most lead encountered in the environment is Inorganic

5 Sources of lead in the environment Lead paint (use banned 1977) in old buildings In water that runs through lead pipes In/ around workplaces using lead Industrial sites- mines, smelters Fishing tackle Ammunition

6 Ammunition Density of lead shot in an area is related to hunting intensity EPA estimated ~72,600 metric tons of lead shot and bullets deposited annually at outdoor shooting ranges All eventually transformed into particulates that are dispersed in the environment Dissolution rates are low Acidic conditions (low ph) can weather fragments more quickly USGS Ruby et al. 1999

7 Exposure in wildlife Exposure most often through ingestion of soil, sediment, food Waterfowl and upland birds- ingest spent shot Predatory/ scavenging birds- consume wounded or dead prey; gut piles USFWS Cornatzer et al National Park Service

8 Lead exposure in wildlife Tranel and Kimmel 2009 >130 species have been reported as ingesting shot, bullets, fragments or prey with lead ammunition Elevated lead levels in bone, tissue or blood

9 Lead content analysis in WI hunter-killed deer - WI Dept Health and Family Services Collected 1lb venison samples from food pantries, meat processors, hunters X-rayed for lead Sample group Commercial processor Hunter processed Number of samples % 98 8% Prevalence of Pb+ samples Hunt et al. 2005

10 Lead in humans Adults typically absorb up to 20% of ingested lead Most of the lead that enters the body is excreted in urine or in the feces Absorbed lead that is not excreted is exchanged primarily among three compartments Blood Mineralizing tissues (bones and teeth)- typically contain the vast majority of the lead body burden Soft tissue (liver, kidneys, lungs, brain, spleen, muscles, and heart)

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12 Effects of lead on wildlife Digestive fluids, stomach acids break lead down Muscular gizzards in birds also breakdown lead Absorbed into blood stream Distributed to internal organs, nervous system, respiratory system

13 Effects of lead on wildlife Hematological (anemia), neurological, nephrological (kidney), immunosuppression, hypertension, reproductive toxicity, endocrine toxicity Reduced body condition, behavioral changes, impaired reproduction, decreased survival May be more susceptible to predation, starvation, other diseases USGS USGS Eagle Valley Raptor Center

14 Waterfowl Ingestion of 1-2 shot can cause bird to waste away over several weeks & die When many shot ingested, birds rapidly deteriorate & die USGS USGS USGS USGS

15 Condors Highly susceptible to small quantities of lead due to their inability to regurgitate pellets Lead fragments from ammunition in carcasses of game and predators (coyotes) or gut piles are the main source USGS Stroud and Hunt 2009 NPS

16 Bald Eagles Lead accounts for 16% of reported deaths in WI 47% admitted to rehabilitators with lead poisoning are Females Only make up 25% of population Concern about long-term reproductive effects Wildlife Center of Virginia USGS Hunt et al Jacobsen et al. 1977

17 Iowa Bald Eagles in Iowa have rebounded dramatically Bald Eagles with high lead levels are admitted to rehabilitators every year

18 Eagles admitted to Iowa rehabilitation centers by month January February March April May June July August September October November December total admitted to rehabilitators showing lead poisoning or exposure Iowa Sierra Club

19 How affected is the whole population? Testing feces of nesting and wintering eagles for lead Winter vs Spring MS River vs Non-MS River Compare lead levels freeflying eagles to lead levels in rehabilitation eagles

20 Other wildlife Mourning doves If ingest large numbers of shot will quickly die 26% fewer eggs hatched after ingestion of 1 pellet Trumpeter swans Ingest lead shot in sediments 25% of reported deaths in WI due to lead poisoning Phil Myers Iowa DNR

21 Alternatives to lead (pros, cons) Non-lead bullets fragment less Several alternatives are approved and available for hunting Steel, tungsten, copper, tin, composites Cost of lead-free ammunition about twice that of lead ammunition Price of lead-free ammunition continues to drop as demand has risen NPS Hunt et al. 2005

22 Regulations Phase out by 1991 of lead shot for hunting waterfowl and coots Motivated by poisoning of Endangered Bald Eagles No lead for hunting big game and non-game species in California Condor range Does not apply to upland game hunters Regulations by state assembled by Wildlife Society nts/lead.and.wildlife.pdf

23 Regulations- Illinois Only nontoxic shot can be used when hunting snipe or rail Only non-toxic shot when removing nuisance blackbirds, cowbirds, grackles and crows Non-toxic shot required in certain state parks and state wildlife areas for mourning dove hunting Mourning dove hunters encouraged to use steel or other non-toxic shot

24 Regulations- Iowa Certain Wildlife Mgmt Areas require non-toxic shot for all hunting Excluding deer and wild turkey Many counties require only non-toxic shot to be used on state and federal lands Only non-toxic shot can be used when hunting rails or snipe

25 Regulations- Wisconsin Non-toxic shot required on wildlife refuges and waterfowl protection areas Excluding deer, small mammals with rifle/slug Non-toxic shot required for snipe and rail on all lands, and for mourning doves on DNR-managed land Hunters encouraged to use nontoxic shot for mourning doves on private lands as well as for hunting woodcock Non-toxic shot required for crows outside the normal season and nuisance grackles, red-winged blackbirds and cowbirds

26 Management recommendations For hunters: Bury or cover gut piles so they are less accessible to scavengers Experiment with lead alternatives EPA issued set of best practices for lead at outdoor shooting ranges: Use lime to increase soil ph Use bullet traps Recycle spent lead Containment of lead to prevent migration off-site