Lead Ammunition – Environmental Consequences

We will deal with this very important issue in several different ways.

A general summary of the issues
The summary and conclusions of the academic article “Effects of lead from ammunition on birds and other wildlife: A review and update”
The summary and conclusions of the academic article” Blood and bone lead levels in South Africa’s Gyps vultures: Risk to nest-bound chicks and comparison with other avian taxa”
The summary and conclusions from a recent report from the British wetlands restoration organisation Wildfowl & Wetlands Trust
Attached You-Tube video presentation, Bird Club presentation: Lead poisoning in southern Africa’s Cape and White backed Vultures

………………………………………………………………….

1. General Summary of the Lead Ammunition Issues

Southern Africa’s vast landscapes and rich biodiversity are home to some of the most iconic species on our planet. As we marvel at the beauty of this region, it’s crucial to acknowledge and address the threats that jeopardize its delicate ecosystems. One such threat, often overshadowed but no less significant, is the use of lead ammunition and its adverse environmental effects.

Lead ammunition has long been utilized in hunting and shooting activities across Southern Africa, favoured for its affordability and effectiveness. However, the toxic properties of lead present grave risks to both wildlife and environmental health. When lead bullets are fired, they fragment upon impact, dispersing small particles into the environment.

These lead fragments can persist in soil, water, and vegetation, posing a threat to a myriad of organisms.

The impact of lead ammunition is particularly pronounced in Southern Africa’s avian populations. Birds of prey, scavengers, and waterfowl are especially vulnerable to lead poisoning, with lead poisoning contributing to population declines and local extinctions. When these birds ingest lead fragments from contaminated prey or environments, they suffer from a range of debilitating effects, including neurological damage and impaired reproduction.

Birds may become emaciated and die within 2-4 weeks of ingesting lead. The most common route of exposure to lead for birds is through ingestion of spent lead ammunition fragments and fishing tackle. In live birds, diagnosis of lead toxicosis is made by assessing clinical signs and measuring lead levels in blood.

Looking specifically at vultures – they play a critical role in Southern Africa’s ecosystems, serving as nature’s clean-up crew and helping to prevent the spread of disease by consuming carrion. However, the ingestion of lead fragments from ammunition left in carcasses poses a significant threat to their survival and has been identified as a leading cause of mortality among vultures in the region, contributing to population declines and endangering the stability of ecosystems.

Furthermore, lead contamination extends beyond direct ingestion. Lead particles can leach into water sources, contaminating aquatic ecosystems and posing risks to fish and other aquatic organisms. This not only disrupts the delicate balance of aquatic ecosystems but also threatens the health of those who rely on these resources for sustenance.

The implications of lead ammunition on Southern Africa’s wildlife and ecosystems are profound and far-reaching. The loss of key species not only disrupts ecological balance but also impacts local communities dependent on wildlife for tourism and livelihoods.

However, there is hope. Sustainable alternatives to lead ammunition, such as copper and steel, offer comparable performance while significantly reducing environmental risks. By transitioning to lead-free ammunition, we can mitigate the threat of lead contamination and help safeguard the health of Southern Africa’s ecosystems.

Currently, lead shot is prohibited In England and Wales on all foreshores, in specified Sites of Special Scientific Interest and for the shooting of all ducks, geese and swans, coots and moorhen. In Scotland it is banned for shooting over any wetland. We need to take note of this example. As advocates for conservation and environmental stewardship, we have a responsibility to raise awareness about the environmental impacts of lead ammunition and promote sustainable alternatives. By educating fellow enthusiasts, engaging with policymakers, and supporting research initiatives, we can drive positive change and ensure a brighter future for Southern Africa’s wildlife and ecosystems.

………………………………………………………………………………..

2. Effects of lead from ammunition on birds and other wildlife: A review and update

Ambio 2019, 48:935–953, https://doi.org/10.1007/s13280-019-01159-0

Authors – Deborah J. Pain , Rafael Mateo, Rhys E. Green

Published online: 16 March 2019

Abstract

Poisoning of wild birds following ingestion of lead from ammunition has long been recognised and considerable recent research has focused on terrestrial birds, including raptors and scavengers. This paper builds upon previous reviews and finds that both the number of taxa affected and geographical spread of cases has increased. Some lead may also be absorbed from embedded ammunition fragments in injured birds which risk sub-lethal and welfare effects. Some papers suggest inter-specific differences in sensitivity to lead, although it is difficult to disentangle these from other factors that influence effect severity. Sub-lethal effects have been found at lower blood lead concentrations than previously reported, suggesting that previous effect-level ‘thresholds’ should be abandoned or revised. Lead poisoning is estimated to kill a million wildfowl a year in Europe and cause sub-lethal poisoning in another 3 million.

Modelling and correlative studies have supported the potential for population-level effects of lead poisoning in wildfowl, terrestrial birds, raptors and scavengers.

Conclusions

Recent research supports and supplements more than a century of work on lead poisoning from ammunition sources in birds. The results of this work show that lead poisoning of birds is likely to occur wherever lead ammunition is used and a pathway of exposure exists. Cases of lead poisoning in new species and countries simply reflect that these had not previously been studied. Taxa beyond birds are also affected; recent research highlights risks to mammalian scavengers and predators although this has not been extensively investigated.

Trends in lead poisoning research in birds reflect those in human medicine, with effects detected at ever lower levels of lead exposure and absorption. Large numbers of wild birds suffer welfare effects and are killed by spent lead ammunition annually, and it affects populations. Alternative nontoxic ammunition exists and some has been in widespread use for decades. Removing this avoidable source of environmental contamination and suffering and mortality of wildlife is a matter of political will (e.g. Arnemo et al. 2016; Kanstrup et al. 2018).

3. Blood and bone lead levels in South Africa’s Gyps vultures: Risk to nest-bound chicks and comparison with other avian taxa

Authors – Linda van den Heever a,b,⁎, Hanneline Smit-Robinson a,c,d, Vinny Naidoo e, Andrew E. McKechnie

Science of the Total Environment, Journal homepage: www.elsevier.com/locate/scitotenv, Available online 9 March 2019

Highlights of The Argument

• Lead can impair chick development and enhance vulnerability to anthropogenic threats.

• A significant proportion of evaluated Gyps vultures (including chicks) were exposed to lead.

• In comparison, non-scavenging birds did not display elevated lead concentrations.

• Nest-bound vulture chicks likely received metallic lead fragments from their parents during feeding.

• Hunters are urged to switch to non‑lead alternatives.

Visual Summary of The Argument

Abstract

Poisoning, including secondary lead poisoning, is cited as the single most important cause of vulture mortalities in Africa. To evaluate the prevalence of lead poisoning among South Africa’s Gyps vultures compared to other, non-scavenging birds, we obtained blood and bone samples from Cape (Gyps coprotheres) and White-backed (Gyps africanus) vultures. We found that 66% of White-backed Vultures (n= 110, including 85 nest-bound chicks sampled at Dronfield Nature Reserve) and 80% of Cape Vultures (n = 15) had blood [Pb] in excess of 10 μg/dL, the upper limit of background exposure. Average blood [Pb] were 15.4 μg/dL and 29.7 μg/dL for White-backed and Cape vultures, respectively. Bone samples revealed that 12% of White-backed Vultures (n = 18) and 9% of Cape Vultures (n=75) suffered from subclinical to severe clinical lead poisoning upon their deaths. By contrast, none of the 40 blood, bone or liver samples obtained from non-scavenging bird species were found to exceed background exposure levels.

Our results suggest that, unlike non-scavenging birds, the scavenging lifestyle of Gyps vultures subjects them to lead poisoning on a regular basis. Had environmental sources of lead (e.g., dust) been the source of the lead poisoning at the White-backed Vulture breeding colony at Dronfield, all the chicks would have displayed similar blood lead concentrations. Instead the values ranged from barely detectable to very high, leading us to conclude that metallic lead fragments regurgitated by parents during feeding are responsible for the elevated lead levels in some of the chicks at this site. We conclude the likely source of these is lead ammunition.

Conclusion

We conclude that lead poisoning in southern Africa’s Gyps vultures is a much larger problem than previously thought, affecting not only the adult population but also threatening the development of nest-bound chicks. As it is difficult to conceive of any other behaviour that could possibly expose vultures to metallic lead fragments, we argue that the major avenue of lead exposure involves fragments ingested while feeding on carcasses and/or gut piles of animals shot with lead ammunition. Removing the gut piles from the field could lower the risk of exposure, but may, in some areas, deprive vulture populations of an important source of food. Making the switch to lead-free ammunition would greatly reduce the risk of exposure, not only to wildlife, but also to humans who may inadvertently ingest lead particles embedded in game meat (Grainger Hunt et al., 2009). We also recommend the careful management of supplementary feeding sites, as inadequate scrutiny of carcasses may inadvertently expose scavengers to carcasses of animals killed with lead ammunition (L. van den Heever, pers. obs.).

…………………………………………………………………….

4. Tackling Lead Ammunition Poisoning

https://www.wwt.org.uk/our-work/projects/tackling-lead-ammunition-poisoning/ Wildfowl & Wetlands Trust (WWT)

Introduction

Up to 100,000 waterbirds in the UK and one million in Europe die every year through ingesting poisonous lead shot. But it’s not just birds that it harms.

A true One Health issue

When billions of individual lead shotgun pellets are left to contaminate our wetland and terrestrial habitats, they leave a toxic legacy for our environment, wildlife and people.

It’s hard to think of a better example of a One Health issue – the term used by the World Health Organisation for issues that affect environments, people and animals – than the poisoning caused by lead ammunition worldwide.

Lead ammunition finds its way into wildlife, soils, domestic and companion animals and onto our plates

……………………………………………

The solution

The solution is for shooters to use non-poisonous alternatives to lead ammunition, which are available for all types of guns. There is general consensus among shooters that hunting must be sustainable. As lead ammunition isn’t considered as sustainable, many hunters are already using non-toxic ammunition to prevent poisoning the countryside and reduce the suffering and deaths.

Using non-toxic alternatives would resolve the problem

Field trials comparing lead and steel shot have found no difference in the number of birds killed. This shows that steel shot works just as well. In Denmark, the Netherlands and Flanders, where the use of lead shot was made illegal decades ago, those who shoot do not report problems with effectiveness. Steel shot is the most popular alternative among these countries, and that is likely to be the same in the UK as it works well and is similarly priced. UK hunting organisations have issued guidance for shooters using non-lead cartridges to help address these concerns.

……………………………………………………………………………………..