Ok, I chased down the study Grouse Guy names in his last post:
Lead pellet ingestion and liver-lead concentrations in upland game birds from southern Ontario, Canada.
Kreager N, Wainman BC, Jayasinghe RK, Tsuji LJ.
Department of Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, Canada.
1. The study was done on pen raised birds on a game farm. It has been a game farm since the 1930s. The birds were released the day of the hunt.
2. The island also had shotgun target shooting on it. The birds were not fenced off from the range.
3. No analysis was done on the pen raised birds before they were released. That is there was no control group. The birds could have arrived on the island with high levels of lead in their liver.
4. The analysis focused on bird livers because some Europeans and some indigenoos people consider them a delicacy.
5. The study author's target was public shooting ranges.
6. The authors acknowled that the lead levels in the livers could be from shot fragmentation but go on to discount it.
The following paragraphs I copied out of the study. I thought they were intresting. I added the italic and underline.
This is the abstract:
One-hundred twenty-three gizzards from upland game birds (chukar, Alectoris chukar; and common pheasant, Phasianus colchicus) harvested by hunters in southern Ontario, Canada, were examined for lead pellet ingestion by manual examination of gizzard contents and by radiography. Lead pellets were found to be ingested by chukars (6/76; 8%) and the common pheasant (16/47; 34%). Further, 13% (17/129) of the bird (wild turkey, Meleagris gallopavo; Hungarian partridge, Perdix perdix; chukar; and common pheasant) livers analyzed had elevated lead concentrations (≥6 μg/g wet weight [ww]). Liver-lead concentrations above Health Canada’s guideline for human consumption of fish protein (<0.5 μg/g ww) were found in 40% (51/129) of livers analyzed. Data indicate that the ingestion of lead pellets in upland game birds and the potential consumption of lead-contaminated meat by humans are concerns related to the continued use of lead shotshell for hunting.
I copied the following out of the full report.
In this study, we examine lead pellet ingestion rates for upland game birds (chukar, Alectoris chukar; and common pheasant, Phasianus colchicus) harvested from a heavily hunted area in southern Ontario, Canada, to evaluate bird health. In addition, the potential for lead contamination of upland game bird livers via the embedding of lead pellets/fragments will also be examined through radiography and electrothermal atomic absorption spectrometry (EAAS), as offal is consumed by Native Canadians (Tsuji and Nieboer 1999) and some Europeans (Guitart et al. 2002) as a delicacy.
Gizzards (n = 123) from chukars and common pheasants, and livers (n = 129) from four species of upland game birds (wild turkey, Meleagris gallopavo; Hungarian partridge, Perdix perdix; chukar; and common pheasant), were collected whole from upland habitat located on a private island (approximately 1950 acres) in southern Ontario, Canada. The island was characterized by mixed woodland with monospecific stands of grass (Gramineae), while some fields also contained wheat (Agropyron spp.), burdock (Arctium spp.), and thistle (Sonchus spp.) (Holdner et al. 2004). Different areas of the island experienced different hunting pressure: shooting stations were used primarily for clay target shooting; fields were generally heavily hunted over, with some fields being tilled annually, while others were never tilled; and the fly pen enclosure area housed the upland game birds prior to release (Holdner et al. 2004). Farm-raised birds were released the day of the hunt, though whatever birds that survived earlier hunts were still in the fields. There is not a large overwinter population of birds. The study area has been heavily hunted with respect to indigenous wild turkeys and imported farm-raised chukars, Hungarian partridges and common pheasants for released bird hunting, since the 1930s.
Sample collection was conducted in the fall of 2000. Gizzard and liver samples were not always matched; that is, gizzard and liver were not always collected for each bird. Only lead shotshell has been used to hunt the upland game birds at this location and hunters are restricted to the use of lead shotshells provided by the hunting club. Lead pellet density ranged from 14 pellets per 0.25 m2 in the hunting fields to 2051 pellets per 0.25 m2 in clay target shooting areas (Holdner et al. 2004). Bird movement was not restricted by any physical barriers between target shooting and hunting areas; however, birds were collected from the hunting fields. Although the present study site was atypical in that it was a private shooting range/hunting club, there are at least 211 active public shooting ranges in Ontario where spent lead pellets are contributing to high lead loadings (tons/year) in the environment (Darling and Thomas 2003). Thus, the pellet densities found on the island (Holdner et al. 2004) are not atypical for outdoor shooting ranges in Ontario. The majority of these active shooting ranges are located in southern and central Ontario where luvisolic soils predominates (Darling and Thomas 2003). Since there is no provincial requirement with respect to site remediation of lead pellets at active public shooting ranges, as well as defunct public shooting ranges and private shooting ranges (Darling and Thomas 2003), lead pellets remain in the environment and a potential threat to upland game birds in Ontario.
However, liver-lead levels must be interpreted with caution because even though there is not radiographic evidence of lead fragment contamination, lead fragments could be so fine (Frank 1986) as not to show up on a radiograph or appear as an artifact.
The nontoxic shot regulations do not apply to upland game species such as the American woodcock, which has shown no decrease in mean bone-lead concentrations since the regulations came into effect (Stevenson et al. 2005). Moreover, Scheuhammer et al. (2003) have shown, using stable lead isotopes ratios, that the elevated lead levels in American woodcock were consistent with lead shot ingestion.
That was the last of what I copied from the report.
If the woodcock lead levels have not gone down with the waterfowl lead ban why does it mean that lead shot from upland hunters have replaced the source? I got the isotope argument but the lead is not gone from the waterways and woodcock have different habits than snow geese.
What about studies showing higher concentrations of lead in urban pigeons than in rural pigeons.
Did they measure the blood levels of any of the people eating the bird livers for high concentrations of lead.
Grouse Guy and his ilk pay lip service to public ranges and the acceptability of lead shot there but their ultimate goal is the elimiantion of lead shot period.
Like others here I wonder if he has read these reports or gets his stuff from a National Wildlife Federation "Talking Points" email every morning.
What about the loss of birds from the loss of habitat? Monsanto Roundup farming has drastically reduced the quantity and quality of cover and wild bird feed on the farms around here. Where is lead poisoning in the leading causes of human death in the US?
Again, what about urban pigeons having a higher lead content than rural pigeons? Where are they ingesting lead shot.
What about the study showing urban humans having a higher lead content in their blood the rural humans?
This isn't the dawn of man. There are six billion of us and we have changed the enviroment.
Best,
Mike
Edit: I keep editing out grammer and spelling mistakes.
Last edited by AmarilloMike; 01/11/10 03:56 PM.
