Abstracts from Conference: Ingestion of Spent Lead Ammunition:
Implications for Wildllife and Humans, Boise, Idaho, May 12- 15, 2008

The Peregrine Fund

Abstract

No.

104 **Biological and Societal Dimensions of Lead Poisoning in Birds in**

**the USA**

**Milton Friend (1),** J. Christian Franson (1), William L. Anderson (2)

\(1\) USGS National Wildlife Health Center

\(2\) Illinois Natural History Survey

The ingestion of spent lead shot was known to cause mortality in wild

waterfowl in the USA a century before the implementation of nontoxic
shot

regulations began in 1972. The biological foundation for this transition
was

strongly supported by both field observations and structured scientific

investigations. Despite the overwhelming evidence, various societal
factors

forestalled the transition to nontoxic shot for waterfowl hunting until
1991.

Now, nearly 20 years later, these same factors weigh heavily in current

debates about nontoxic shot requirements for hunting other game birds,

requiring nontoxic bullets for big game hunting in California condor
range and

for restricting the use of small lead sinkers and jig heads for sport
fishing. As

with waterfowl, a strong science-based foundation is requisite for
further

transitions to nontoxic ammunition and fishing weights, and relevant
social

issues must be adequately addressed.

We provide a brief historic review of lead poisoning in birds in the USA
prior to

1970 and proceed to emphasize the biological and social issues that
arose

during the heated conflict that extended from the mid 1960s until the
end of the

1980s and to discuss their resolution. We also outline the broad
spectrum of

conditions under which lead poisoning of birds has occurred in the USA,
thus

providing an overview of the hazards for wildlife exposed to lead in the

environment. These conditions include lead toxicosis in waterfowl in
isolated

areas of Alaska, poisoning of flesh-eating birds from consumption of
lead shot

and bullet fragments in scavenged carcasses and poisoning associated
with

lead from non-hunting activities such as sport fishing, shooting sports,
mining

and consumption of lead-based paint chips and other materials.

Our collective experiences with lead poisoning in birds include
laboratory

research, field investigations and personal involvement in providing

evaluations and testimony that served to guide the U.S. Fish and
Wildlife

Service's phase-in of nontoxic shot requirements for waterfowl hunting
in the

USA. These experiences have taught us that the societal aspects of the
lead

poisoning issue are as important as the biological components and must
be

adequately addressed before alternatives to toxic lead shot ammunition,

fishing weights and other materials will be accepted as an investment in
wildlife

conservation.

Abstract

No.

106 **Technical Review of the Sources and Implications of Lead**

**Ammunition and Fishing Tackle to Natural Resources Prepared by**

**the American Fisheries Society and The Wildlife Society**

**Barnett Rattner**, J.C. Franson, S.R. Sheffield, C. Goddard, N.J.
Leonard, D.

Stang, and P.J. Wingate.

USGS---Patuxent Wildlife Research Center, Beltsville Laboratory,

Beltsville, MD 20705

A joint technical review of lead originating from shooting and fishing
activities

was prepared for the American Fisheries Society and The Wildlife Society
with

the ultimate goal of drafting a position statement. Spent lead
ammunition

greatly exceeds estimates of lost fishing tackle. Lead shot, bullets,
and fishing

tackle are not readily dissolved, but in some circumstances lead can be

mobilized (soft acidic waters) to exceed water quality criteria, cause
lethality

(some species/life stages of fish and amphibians), and elicit
hematological and

pathological lesions. Toxicity of ingested lead shot is well-documented
in birds

and mammals, but not in fish or amphibians. A number of studies have
shown

that the ban on lead shot for hunting waterfowl reduced the incidence of
lead

poisoning. However, upland and scavenging birds remain at risk, and many

states and provinces have restricted the use of lead ammunition for
species

other than waterfowl. Hazards of lead fishing sinkers to wildlife were
only

recognized in the 1970's (swans, loons). Restrictions on sale and use of
lead

fishing tackle have been instituted in several countries to protect
these and

other species. However, effects of lead fishing tackle on wildlife
populations

have not been adequately studied, and hazards to fish populations are

unknown, but thought to be minimal. Regulatory efforts have been
undertaken

to evaluate and approve safe alternatives to lead shot. However, except
for

hunting waterfowl and coots, and mourning doves in some locations,
nontoxic

shot and bullets are not routinely used for other types of shooting.
Substitutes

for lead fishing tackle are commercially available, and because of their

similarity to approved shot, toxicity testing of many of these products
may not

be warranted. Our understanding of the hazards of lead and alternative

materials used in shooting and fishing would be improved by research,

monitoring, and modeling efforts of fate, exposure and toxic effects.
There are

at least three position options that might be adopted by the American
Fisheries

Society and The Wildlife Society. Namely, the introduction of lead into
the

environment from hunting, shooting sports and fishing activities (1) is

adequately regulated and the toxicological consequences of ingestion of
lead

are currently considered acceptable, (2) could be restricted in
locations where

lead poses an unacceptable hazard to biota and their supporting habitat,
or (3)

could be phased out with a goal of complete elimination. The leadership
of

both societies could interact with various government, academic and

conservation entities to disseminate information about hazards and toxic

effects of lead ammunition and tackle, as well as the availability and
ecological

benefits of safe alternatives.

Abstract

No.

202 **Lead Exposure in Mourning Doves: Results of a Field Survey and**

**Comparisons with Experimental Findings**

**J. Christian Franson** (1), Scott P. Hansen (1,2), John H, Schulz (3)

\(1\) USGS National Wildlife Health Center

\(2\) Current affiliation: Wisconsin Department of Natural Resources

\(3\) Missouri Department of Conservation

To evaluate lead exposure in mourning doves (*Zenaida macroura*), we

examined carcasses of 4,884 hunter-killed doves from Arizona, Georgia,

Missouri, Oklahoma, Pennsylvania, South Carolina, and Tennessee. One or

more ingested lead pellets were found in 2.5% of 4,229 carcasses
collected at

hunting areas where the use of lead shot was permitted, with ingestion
rates

among areas varying from 0% to 20.8%. Ingested steel shot were found in

2.4% of 655 carcasses collected from two areas requiring the use of
nontoxic

shot. Of the dove carcasses for which age was determined, 69.9% were
hatch

year and 30.1% were after hatch year. With one exception, all doves with

ingested shot were hatch year birds, and the proportions of hatch year
males

and females with ingested lead shot did not differ significantly. Doves
with

ingested lead shot had from one to 43 pellets in their gizzards, with
3.8%

having \>15 lead pellets. Of the birds with ingested steel shot, 25% had
\>15

steel pellets in their gizzards. The frequency of lead shot ingestion in
doves

did not differ between birds collected early in the hunting season
(September 1

through September 7) and those collected later in the season (September
8

through December 24). From the areas where lead shot was used for
hunting,

8.3% of doves had liver lead concentrations \>6 ppm dry weight and 26.8%
had

\>20 ppm dry weight of lead in their wing bones, concentrations often
used as

indicators of lead exposure above normal background levels. Where steel
shot

was required for hunting, 2.0% of doves had liver lead concentrations
\>6 ppm

dry weight and 11.1% had bone lead concentrations \>20 ppm dry weight.
The

median liver and bone lead concentrations in doves with ingested lead
shot

were 36.89 ppm dry weight and 89.33 ppm dry weight, respectively. Median

liver and bone lead concentrations in doves without ingested shot were
\<1.0

ppm dry weight and \<3.0 ppm dry weight, respectively. In doves without

ingested lead shot, the median concentration of lead in wing bones of
after

hatch year birds was significantly greater than the median in wing bones
of

hatch year birds. We compare and interpret these findings in relation to

previous field surveys and recent experimental studies of the ingestion
and

toxicity of lead shot in mourning doves. Finally, we discuss the issue
of

ingested lead shot in mourning doves as a source of secondary lead
exposure

for predators and scavengers.