Latest Developments with Lead Ammunition - More Reasons for Hunters' Action
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July 2008
During recent years the CIC has been increasingly focused on the issue of lead shot for hunting. The first priority has been to help with phasing out the use of lead shot in wetlands; due to the clear evidence that waterfowl ingest lead shot and consequently suffer a substantial risk of lead intoxication and mortality. However, research and practical experience now reveal a need to widen the focus to other taxa and ecosystems, just as the use of lead in rifle bullets has also come on the international agenda.
Through the CIC newsletter we have informed members about these developments and at the 55th CIC General Assembly in Marrakech we hosted round-table discussions in which we were reassured of the need to follow the situation and keep members updated. The workshop covered the present status of knowledge on intoxication problems with lead shot and an overview of the ballistic aspects of shot-gunning and the various non-toxic shots available (see Table below). Attendees unanimously supported a CIC policy of seeking to phase-out lead ammunition but there was genuine concern that not enough was known about non-toxic shot. We heard several contradictory arguments and there is an urgent need to resolve the issues, with many of those present offering to help. Of greatest concern are the ballistics and lethality features of non-toxic materials such as iron (sometimes known as soft steel). A simple measure to compensate for the lower specific gravity of lighter non-toxic metals is to increase the shot size by 0.5 mm. Overall the evidence shows that efficiency is related to the shooters performance more than to the equipment used.
The situation is changing rapidly however with new evidence now appearing almost monthly and the scope of discussion is broadened from wildlife management to include also food and health aspects. This makes game-birds central to the discussions. Thirty years ago, many hunters thought that the results about lead ingestion in game-birds were reassuring; the problem was less severe than in waterfowl and the problem had existed for at least 133 years, so went the argument, it could not be all that alarming. Unfortunately we now know these views were misguided.
The first reports of the problem appeared in England as long ago as 1875, when two pheasants were found with the typical signs of ingested lead poisoning; one had ingested 13 lead shot, the other 4. A further similar case was reported in 1882 and then nothing for 40 years, until Tegetmeier reported he had “frequently” found pellets of shot in the gizzards of pheasants. The issue died away again and as late as March 1955, when the results of the fluoroscopy of 21,000 quarry species in the USA were announced, no lead ingestion was reported. The fact that 5.3% of female pheasants carried lead shot (compared to 27.34% of males (legal quarry)) was all attributed to illegal shooting.
Today there can be no doubt the problem in game-birds is similar to that in waterfowl a few years back, before the bans on use of lead in wetlands, and that ingestion rates are climbing. The highest level of ingested lead in pheasants was reported in 2006; the highest levels in red-legged and chukar partridges have just been reported in 2008. In all three species and the grey partridge the percentage of birds that have been exposed to ingested lead shot is 5-25%, or 2-4 times the percentage of gizzards that contain ingested lead shot. The variability is high for several reasons. For example levels are higher where soils are fine or chalky, where lead is mistaken for grit, or the ground is rocky, where lead is likely to remain on the surface.
Against this background, a very important conference has just (12-15 May) taken place entitled “Ingestion of Spent Lead Ammunition: Implications for Wildlife & Humans”. Almost 500 people attended this meeting held under the auspices of the Peregrine Fund, Boise, Idaho. Almost 60 papers will be published in book form before year end. There are many new findings. In his summing up Professor Ian Newton, Chairman of the UK’s Royal Society for the Protection of Birds recalled the issue that had brought everyone together “The banning of the use of lead in ammunition over wetlands has greatly reduced the huge mortalities in waterfowl and others which were formerly so apparent. We can assume that this measure has reduced lead consumption by people and also by some scavengers such as bald eagles. However other uses of lead in ammunition have continued unabated…”
Meanwhile, as papers at the Conference presentations revealed, low levels of lead that were formerly considered benign in people, have been shown to have adverse effects. Exposure to lead shot in game birds and lead bullet fragments in venison has also been shown to be widespread with serious concern about people who consume a lot of game meat and for species, such as the California condor, exposed to bullet fragments when feeding on deer carcasses. Professor Newton concluded there were two ways of reducing the use of lead ammunition: 1. convincing the authorities to introduce appropriate legislation or regulation and 2. Informing hunters about the human health problems, asking for their help on wildlife issues and hoping they would appreciate the advantages of switching to non-toxic ammunition. Either way this puts the spotlight fairly and squarely on hunters.
Dr. G R (Dick) Potts
President
Small Game Commission
Niels Kanstrup
President
Migratory Birds Commission
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