lead exposure in condors
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Lead Exposure in Condors
Monterey County Fish and Game Commission MeetingAugust 10, 2010
Presented By Joe Burnett, Sr. Wildlife BiologistVentana Wildlife Society
Condor Facts
North America’s largest flying land bird with a 9-1/2 foot wingspan, weighing 20-25lbs
Can live 50-60 years in the wild Typically lay one egg every other year and mate for life
Condor Facts
Opportunistic scavengersDo not kill animals and do not have talonsCondors primarily scavenge on pig, deer, sea lion and cattle
carcassesCurrently, condors feed on both supplemental and wild food
sources
Condor Recovery Timeline
1987- Last Wild Condor Removed From The Wild, Only 27 Condors Remain, all in Captivity
1988- First Egg Laid In Captivity1992- First Release Of Captive-born Condors In
Southern CA1996- First Release In Arizona1997- First Release In Monterey County, Big Sur2003- First Releases In Pinnacles And Baja, Mex2005- First Successful Nest In Southern CA2007- First Successful Nest In Monterey County2009- First Successful Nest In San Benito County2010- CA Free-Flying Population reaches 90+ birds
Recovery Goals- California
150 free-flying condors in CA.
150 condors in captivity15 Breeding Pairs in the wildPositive growth rate for wild flock
Currently 96 = 54 in Cen Cal and 42 in So Cal150 +
12 PairsNO
Condor Release Sites
Limiting Factors
Lead Toxicosis Powerline collisionsIntentional ShootingTrash Ingestion in nestlings West Nile VirusDDTNatural:Predation (Golden Eagles, Coyotes,
Rattlesnakes)Wild Fires
Vaccine protects condorsTrash Clean-up
Education/OutreachRemoval/marking lines
Ban on lead ammo in condor range
Limits egg production
Lead Toxcity and Wildlife
Federal requirement banned lead shot for hunting waterfowl in 1991 Bald Eagles, our National Symbol, are hunters/scavengers that have
been documented ingesting spent lead ammo in carcasses, many die as a result
Lead Exposure in Condors
Source of Lead in Condors
Lead ammunition is the primary source of lead exposure in condors
How do we now this? Pathway exists- Lead fragments are ingested when condors
consume hunter-shot game/gut piles. Lead source confirmed by recovery of lead shot and bullet
fragments from digestive tracts of condors. Tissue and blood isotopes match those of lead ammo. Other lead sources ruled out:
◦Fishing sinkers◦Tire irons◦Paint ◦Atmospheric/environmental
Radiographs of spent lead ammo fragments in rifle-killed deer
Effective July 1, 2008
Post-ban Lead Exposure
The number of condors exposed to lead levels (higher than 10 mg/dl) has dropped since ban
Isolated severe poisoning events still persist In 2009, two condors were lost to lead
poisoningIn 2010, nest at Pinnacles failed after chick
and parents were lead-poisonedCase studies condor 303 and 401…
Condor 303, lead shot in gut
Condor 401- Lead shot in gut
Condors and Hunting
Does Non-lead ammo…• Provide condors a safe food source? YES• Make hunting illegal in condor areas? NO• Requires use of non-lead ammo? YES• Benefits other wildlife like Bald Eagles? YES
Non-lead Bullets
Non-Lead Bullets: Do they work?
Non-lead bullets were designed for hunters, not for condor biologists. They are used by hunters and hunting guides all over the world
Ballistics equal to Lead ammoNon-lead bullets kill gameYes, they do work
Transitioning to Non-lead ammo
Must sight in your rifle with non-lead ammoGuns shoot differently, need to find out what
non-lead ammo works best with your gunThey can pass through animal: they expand on
impact (no fragmentation), but carry more energy due to increased weight retention.
You still get same stopping power and same end result= one dead animal
Fouling- Newer non-lead ammo has fouling similar to copper jacketed lead ammo.
Non-lead ammo Manufacturers
Ammo Brothers, Barnes Bullets Inc. , Black Hills Ammunition, CCI , Cutting Edge Bullets, Custom Cartridge, Inc. , Dakota Ammo (COR-BON/Glaser) , D Dupleks Ltd. , Dynamic Research Technologies (DRT), Federal Cartridge Company , Hornady Mfg. Co, International Cartridge Company, Magtech Ammunition Company, Miwall Corporation , North Fork Bullets, Nosler, Inc. ,P-bar Co., LLC , Remington Arms Co., Inc , Sinterfire, Inc ,Snake River Ammunition , Stars & Stripes Ammunition, Tombob Outdoors, LLC , Weatherby, Inc. ,Winchester Ammunition
How can we get better hunter compliance?
Hunter compliance is very good, but not yet 100%.
Without full compliance, condors will remain at risk to lead poisoning.
One lead-tainted carcass can poison a flock
Attend upcoming Lead-free shooting event and sight in your rifle with free ammo.◦Ft. Hunter Liggett: Friday, August 13th (10am-3pm)◦Camp Roberts: Saturday, August 21st (10am-3pm)
Other ways to Increase Compliance…
Non-lead ammo Rebate Program◦Provide hunters a coupon to discount the costs of
non-lead ammo. In exchange, ask the hunter to complete a survey form
Provide hunters direct evidence of non-lead ammunition killing game◦Hire a professional pig hunting guide to lead a hunt
and document results of non-lead bullets.◦If possible, recover bullets from carcasses and/or
evaluate dropping power.◦Provide this data in a report to Monterey Fish and
Game Commission and distribute to hunter
Can condors and hunters coexist?
YES
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