In reading group earlier this month Linda Riquelme led a discussion on the issue of wildlife culling. This is something that relates to projects a few of us in the lab work on. For example, the management of endangered Buloke Woodlands in the Victorian Mallee, which involves an annual kangaroo cull at Wyperfeld National Park in north-western Victoria.
Not all wildlife management strategies involve culling, though it is used in many situations: kangaroo culls in eastern Australia to manage grazing, badger culls in the UK to control bovine tuberculosis, culling of exotic brushtail possums in New Zealand, the list goes on.
A paper published earlier this year by Dubois and colleagues proposed a list of seven stepwise “principles for ethical wildlife control”. These principles came about as a result of a 2-day workshop held in 2015 that brought together 20 international experts from academia, industry, and non-governmental organisations. The aim of the workshop was to develop a set of steps that managers could work through to determine whether it was possible to mitigate a problem by changing human behaviour, or if not, whether a problem was serious enough to warrant a cull.
These seven principles are:
- Begin, wherever possible, by altering human practices that cause human-wildlife conflict and by developing a culture of coexistence. Dubois and colleagues recommend the root cause of the conflict be looked at first. Modifying human behaviour, though easier said than done, should take priority. Education programs are necessary for changing community attitudes and increasing tolerance towards wildlife.
- Justify that significant harms are being caused to people, property, livelihoods, ecosystems and/or other animals. An objective evaluation of the situation should be carried out, that considers all options and asks the question “what if we didn’t cull?”. The authors state that a decision to control wildlife is generally based on “cultural carrying capacity”, the number of animals that people will tolerate in an area, rather than a biological one. Cultural carrying capacity can shift as a result of education, increased tolerance, and preventative measures.
- Have measurable outcome-based objectives that are clear, achievable, monitored and adaptive. Management actions may vary depending on whether the objective is to reduce crop damage, prevent disease transmission, or to increase a population of an endangered species. Understanding this, as well as the ecology and demography of the focal population, is important for the success of a control program. Monitoring is also a crucial, as it enables managers to adapt their control strategies over time.
- Predictably minimize animal welfare harms to the fewest number of animals. The authors point out that nonlethal methods don’t always cause less harm. Translocation, for example, might hardly faze some animals, but it can also lead to increased suffering if an animal can’t find food or shelter in a new territory, or is killed by another animal competing for the same patch.
- Be informed by community values as well as scientific, technical, and practical information. Any decision to manage wildlife should consider community values. A cull may cause a public reaction, especially if it happens close to an urban centre. Managers should engage with the community before any wildlife control program is undertaken, considering different social values within the community and incorporating these into their strategies. Dubois and colleagues highlight the case of Little Penguins on Middle Island in Victoria as a successful example of community engagement in decision making. With the support of the local community, the island was closed to visitors and Maremma dogs were placed on the island to guard the breeding penguins from fox predation. As a result, the penguin population increased. The success of this program resulted from a combination of community engagement, education, and awareness.
- Integrate into long-term systematic management plans. Any benefits that may result from management might only be short-lived if actions don’t form part of a long-term plan. For example, after foxes had been removed from Middle Island, preventing their return was crucial for penguin breeding success.
- Base decisions on the specifics of the situation, rather than negative labels applied to the target species (e.g. pest, overabundant). The authors argue that wildlife control should not be undertaken just because a negatively labelled species is present. While introduced and abundant species can alter native ecosystems (especially on islands), many introduced species have integrated innocuously into local environments, or may even fill an ecological niche left by an extinct species. Another point they made was that animals given negative labels such as “pest” are more likely to receive less welfare consideration than more “valued” species. This principle serves as a reminder that decisions should be based on careful analysis of the problem and outcomes, not just because an animal is considered a “pest”.
In our discussion of this paper, it was pointed out that while the authors argued that labelling an animal “overabundant” or a “pest” should not in itself justify a cull, they stated that an objective of culling may be to restore an ecosystem to its “pristine state”. How is one label justified, but not the other? It is also assumed that a “pristine” ecosystem existed before the introduction of that animal. What is meant by “pristine” exactly?
One of the biggest questions when culling is “what happens to the carcasses?” This was an important point of discussion, and several issues were raised:
- What happens to animal carcasses after a cull, particularly in Australia?
- Should the carcasses be left to decompose, be buried, or be processed for pet or human consumption?
- Should there be economic benefits as a result of culls? If so, who should receive those benefits?
In the case of kangaroo culls in Australia, decisions about sustainable harvesting are decided by the States and Territories. Currently, Queensland, New South Wales, South Australia, and Western Australia have EPBC-approved management plans allowing for commercial harvest. Decisions about whether to cull in National Parks and Reserves or on private land is also left to the States and Territories. For example, in NSW commercial kangaroo harvest is only permitted on private land with the permission of the owner, and prohibited within National Parks and Reserves.
Another factor influencing the harvest of kangaroos is the price of the meat. If meat prices are low, there is no financial incentive to harvest. This causes concern among farmers, as kangaroo populations may increase to a point where populations become unsustainable. Prices are also a hurdle to meat not being wasted in remote parts of those States where the industry does operate, raising issues of food wastage.
Our discussion linked back to a talk given by Evie Merrill from the University of Alberta, who is currently visiting the lab. Evie’s talk had touched on the theme of culling of deer as a preventative measure against the spread of chronic wasting disease in deer.
In Evie’s account, it was revealed that deer killed during culls are expected to be used for meat, and public opposition to culling in her example was triggered by imagery of mass burials of carcasses – that resulted from demand for meat being exceeded by the size of the cull.
This then introduced discussion of the policy in Australia of not profiting from culling of protected species. If such animals are culled, particularly for conservation purposes, is it ethical to make a profit from it?
Some of the issues that arise with culling are similar to those of trophy hunting: for example, allowing hunters to pay a fee to shoot animals as part of a wildlife management program could bring in some money, which could be used for conservation; on the other hand, this could create a market or a dependency on this source of funding. People may also have strong moral objections to killing for recreation, not to mention the seemingly oxymoronic idea of killing for conservation.
The principles listed in this paper focus on the question of “when should we cull?” One point raised was whether rephrasing this question to “when should we avoid culling?” would turn the entire conversation around?
Culling is often a controversial and emotive topic, and there was a lot of thought-provoking discussion. This paper didn’t take sides on the culling debate; rather, it outlined a list of steps to help managers in their decision-making process. Many papers have been published tackling this issue, though this is the first to bring together international perspectives, developing a list of clear, logical, and practical principles for wildlife control.