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Lead (Pb) is a toxic element banned from fuel, paint and many other products in most developed countries. Nonetheless, it is still widely used in ammunition, including rifle bullets, and Pb-based bullets are almost universally used in Australia. For decades, poisoning from Pb shot (shotguns) has been recognised as a cause of disease in waterfowl and Pb shot has been subsequently banned for waterfowl hunting in many jurisdictions. However, the risks posed by Pb-based bullets (rifles) have not been similarly recognised in Australia. Pb-based rifle bullets frequently fragment, contaminating the tissue of shot animals. Consuming this Pb-contaminated tissue risks harmful Pb exposure and, thus, the health of wildlife scavengers (carrion eaters) and humans and their companion animals who consume harvested meat (game eaters). In Europe, North America and elsewhere, the environmental and human health risks of Pb-based bullets are widely recognised, and non-toxic alternatives (e.g. copper-based bullets) are increasingly being used. However, Australia has no comparable research despite widespread use of shooting, common scavenging by potentially susceptible wildlife species, and people regularly consuming shot meat. We conclude that Australia has its collective 'head in the sand' on this pressing worldwide One Health issue. We present the need for urgent research into this field in Australia.

AbstractLead-based ammunition (gunshot and bullets) frequently leaves small lead fragments embedded in the meat of wild-shot game animals. Australia produces several commercial game meat products from wild animals harvested with lead-based ammunition and has a growing population of recreational hunters. However, no studies have previously investigated the frequency of lead fragments or lead concentrations in Australian game meat. We examined 133 Australian minced game meat items of four types for evidence of lead contamination. Samples were meat from kangaroos (Macropus and Osphranter spp.; n=36) and Bennett's wallabies (Notamacropus rufogriseus; n=28) sold for human consumption, and deer ('venison'; multiple spp.; n=32) and stubble quail (Coturnix pectoralis; n=37) harvested for private consumption by recreational hunters. All packages were studied by digital radiography to detect the presence of radio-dense fragments, assumed to be lead fragments from ammunition. Visible fragments were absent in commercially available kangaroo products, but were present in 4%, 28% and 35% of wallaby, venison and quail, respectively. Mean meat lead concentrations (mg/kg wet weight) were 0.01 ± 0.01 for kangaroo, 0.02 ± 0.01 for wallaby, 0.12 ± 0.07 for venison, and 1.76 ± 3.76 for quail. The Australian food standards threshold for livestock meat (0.1 mg/kg w.w.) was not exceeded by any kangaroo or wallaby products but was exceeded by 53% and 86% of venison and quail, respectively. Radiography only detected 35% of samples that were above the food safety threshold. While average lead concentrations in commercially available macropod (kangaroo and wallaby) meat were low, those in recreationally harvested game meat may pose health risks for hunters and associated consumers.

Haematology parameters (N = 24) and serum biochemistry parameters (N = 35) were determined for wild Eurasian beavers (Castor fiber), between 6 months – 12 years old. Of the population tested in this study, N = 18 Eurasian beavers were from Norway and N = 17 originating from Bavaria but now living extensively in a reserve in England. All blood samples were collected from beavers via the ventral tail vein. All beavers were chemically restrained using inhalant isoflurane in 100% oxygen prior to blood sampling. Results were determined for haematological and serum biochemical parameters for the species and were compared between the two different populations with differences in means estimated and significant differences being noted. Standard blood parameters for the Eurasian beaver were determined and their ranges characterised using percentiles. Whilst the majority of blood parameters between the two populations showed no significant variation, haemoglobin, packed cell volume, mean cell haemoglobin and white blood cell counts showed significantly greater values (p< 0.01) in the Bavarian origin population than the Norwegian; neutrophil counts, alpha 2 globulins, cholesterol, sodium: potassium ratios and phosphorus levels showed significantly (p< 0.05) greater values in Bavarian versus Norwegian; and potassium, bile acids, gamma globulins, urea, creatinine and total calcium values levels showed significantly (p< 0.05) greater values in Norwegian versus Bavarian relict populations. No significant differences were noted between male and female beavers or between sexually immature (< 3 years old) and sexually mature (≥ 3 years old) beavers in the animals sampled. With Eurasian beaver reintroduction encouraged by legislation throughout Europe, knowledge of baseline blood values for the species and any variations therein is essential when assessing their health and welfare and the success or failure of any reintroduction program. This is the first study to produce base-line blood values and their variations for ...

Context In response to the toxic health threats posed by lead (Pb), there is currently a focus on transitioning to lead-free bullets for shooting wild animals. Aim We aimed to quantify the killing efficiency and animal welfare outcomes of lead-based and lead-free (copper-based) bullets for ground-based shooting of sambar deer (Cervus unicolor) in Victoria, south-eastern Australia. Methods We used shooter-collected data from recreational diurnal hunting and professional nocturnal culling during 2020–2021. Shooters recorded rifle calibre, cartridge type, bullet mass, bullet type, shooting outcomes (miss, wound or kill), shooting distance, flight distance (the distance between where the animal was shot and where it died) as an assumed positive correlate of time to incapacitation, anatomical zones struck by bullets, and frequency of bullet exit wounds. We used flight distance as our response variable, assuming that it is positively correlated with time to incapacitation. To examine the role of several predictor variables (including bullet type) potentially influencing flight distance, the dataset was reduced to those deer killed with a single thoracic shot. Key results Our data captured shooting events involving 276 deer, with 124 deer shot at with lead-based bullets and 152 with copper-based bullets. Most (87%) of the deer were killed with a single shot. The frequency of non-fatal wounding was <4% for both bullet types and there was no distinct difference in the probability of a single shot kill for deer shot with either bullet type. For those deer killed with a single thoracic shot (n = 198), there was no evidence that bullet energy or shooting distance influenced flight distance. After accounting for differences in terminal kinetic energy, the mean flight distance of deer shot with lead-free bullets (35 m) was 56% greater than that of deer shot with lead-based bullets (22 m). Conclusions Lead-based and lead-free bullets produced similar animal welfare outcomes for shooting sambar deer. Implications A transition to lead-free ammunition for shooting sambar deer would have minimal impact on efficiency or animal welfare outcomes.

Several important techniques for managing wildlife rely on ballistics (the behaviour of projectiles), including killing techniques (shooting) as well as capture and marking methods (darting). Because all ballistic techniques have the capacity to harm animals, animal welfare is an important consideration. Standardised testing approaches that have allowed refinement for other physical killing and capture methods (e.g. traps for mammals) have not been applied broadly to ballistic methods. At the same time, new technology is becoming available for shooting (e.g. subsonic and lead-free ammunition) and darting (e.g. dye-marker darts). We present several case studies demonstrating (a) how basic ballistic testing can be performed for novel firearms and/or projectiles, (b) the benefits of identifying methods producing undesirable results before operational use, and (c) the welfare risks associated with bypassing testing of a technique before broad-scale application. Following the approach that has been used internationally to test kill-traps, we suggest the following four-step testing process: (1) range and field testing to confirm accuracy and precision, the delivery of appropriate kinetic energy levels and projectile behaviour, (2) post-mortem assessment of ballistic injury in cadavers, (3) small-scale live animal pilot studies with predetermined threshold pass/fail levels, and (4) broad-scale use with reporting of the frequency of adverse animal welfare outcomes. We present this as a practical approach for maintaining and improving animal welfare standards when considering the use of ballistic technology for wildlife management.