Not a biologist, not an expert, just a reader. I have read most of these 11 pages and the fact is the California Condor was in trouble 60 years ago.
Bald Eagles are carrion feeders, and how many have died from eating dead salmon filled with mercury from the Great Lakes, probably far more than lead.
Dabbling ducks and some divers are more susceptible to lead poisoning by the nature of which they feed, and if the plants are not anchored firmly in the silt will inject roots and all to include maybe a pellet or two occasionally. How many does it take to kill a duck that ingests them and how long? Lead wounded or steel wounded, most are going to die anyway.
As to an upland bird ingesting pellets, kind of far fetched as they peck for their food and I am certain they can tell the difference between a pellet and seeds and some young sprouts.
Cows tear grass to eat and use their tongue to do so, and therefore cannot get low grass, on the other hand, sheep eat roots and all, how many of them get lead poisoning?
