Quantifying the effects of delisting wolves after the first state began lethal management

Predators and their protection are controversial worldwide. Gray wolves, Canis lupus, lost U.S. federal protection (delisting) and the State of Wisconsin began lethal management first among all states and tribes that regained authority over wolves. Here we evaluated the initial success of reaching the state’s explicit objective, “…to allow for a sustainable harvest that neither increases nor decreases the state’s wolf population…” We used official state figures for hunter-killed wolves, population estimates from April 2017–2020, and the latest peer-reviewed model of individual wolf survival to estimate additional deaths resulting from federal delisting. More than half of the additional deaths were predicted to be cryptic poaching under the assumption that this period resembled past periods of liberalized wolf-killing in Wisconsin. We used a precautionary approach to construct three conservative scenarios to predict the current status of this wolf population and a minimum estimate of population decline since April 2020. From our scenarios that vary in growth rates and additional mortality estimates, we expect a maximum of 695–751 wolves to be alive in Wisconsin by 15 April 2021, a minimum 27–33% decline in the preceding 12 months. This contradicts the state expectation of no change in the population size. We draw a conclusion about the adequacy of regulatory mechanisms under state control of wolves and discuss the particular governance conditions met in Wisconsin. We recommend greater rigor and independent review of the science used by agencies to plan wolf hunting quotas and methods. We recommend clearer division of duties between state wildlife agencies, legislatures, and courts. We recommend federal governments reconsider the practice of sudden deregulation of wolf management and instead recommend they consider protecting predators as non-game or transition more slowly to subnational authority, to avoid the need for emergency relisting.

Evaluating how lethal management affects poaching of Mexican wolves

Despite illegal killing (poaching) being the major cause of death among large carnivores globally, little is known about the effect of implementing lethal management policies on poaching. Two opposing hypotheses have been proposed in the literature: implementing lethal management may decrease poaching incidence (killing for tolerance) or increase it (facilitated illegal killing). Here, we report a test of the two opposed hypotheses that poaching (reported and unreported) of Mexican grey wolves ( Canis lupus baileyi ) in Arizona and New Mexico, USA, responded to changes in policy that reduced protections to allow more wolf-killing. We employ advanced biostatistical survival and competing risk methods to data on individual resightings, mortality and disappearances of collared Mexican wolves, supplemented with Bayes factors to assess the strength of evidence. We find inconclusive evidence for any decreases in reported poaching. We also find strong evidence that Mexican wolves were 121% more likely to disappear during periods of reduced protections than during periods of stricter protections, with only slight changes in legal removals by the agency. Therefore, we find strong support for the ‘facilitated illegal killing’ hypothesis and none for the ‘killing for tolerance’ hypothesis. We provide recommendations for improving the effectiveness of US policy on environmental crimes, endangered species and protections for wild animals. Our results have implications beyond the USA or wolves because the results suggest transformations of decades-old management interventions against human-caused mortality among wild animals subject to high rates of poaching.

Evaluating how lethal management affects poaching of Mexican wolves

Despite illegal killing (poaching) being the major cause of death among large carnivores globally, little is known about the effect of implementing lethal management policies on poaching. Two opposing hypotheses have been proposed in the literature: implementing lethal management may decrease poaching incidence (‘killing for tolerance’) or increase it (‘facilitated illegal killing’). Here, we report a test of the two opposed hypotheses that poaching (reported and unreported) of Mexican grey wolves (Canis lupus baileyi) in Arizona and New Mexico, USA, responded to changes in policy that reduced protections to allow more wolf-killing. We employ advanced biostatistical survival and competing-risk methods to data on individual resightings, mortality and disappearances of collared Mexican wolves, supplemented with Bayes Factors to assess strength of evidence. We find inconclusive evidence for any decreases in reported poaching. We also find strong evidence that Mexican wolves were 121% more likely to disappear during periods of reduced protections than during periods of stricter protections, with only slight changes in legal removals by the agency. Therefore, we find strong support for the ‘facilitated illegal killing’ hypothesis and none for the ‘killing for tolerance’ hypothesis. We provide recommendations for improving the effectiveness of US policy on environmental crimes, endangered species, and protections for wild animals. Our results have implications beyond the USA or wolves because the results suggest transformations of decades-old management interventions against human-caused mortality among wild animals subject to high rates of poaching.

Co-existing with dingoes: Challenges and solutions to implementing non-lethal management

ABSTRACT Where wild carnivores such as the Australian dingo interact with and impact on livestock enterprises, lethal control and landscape-scale exclusion are commonly employed. However, interest in alternative non-lethal management approaches has recently increased. This is evidenced by several reviews of non-lethal methods that can be said to be working toward improved coexistence. Nevertheless, and despite centuries of conflict, our non-lethal human-wildlife coexistence toolkit remains remarkably deficient. Innovation and evaluation of non-lethal methods should be prioritised to ensure that the economic, ecological, cultural and intrinsic values of dingoes are retained, while minimising the economic and emotional costs of conflict with livestock producers. In this paper we summarise some of the practical tools that might be effective in relation to the dingo, particularly those yet to be formally investigated, and discuss some of the possible hurdles to implementation. We conclude by suggesting pathways for human-dingo coexistence, and the steps necessary for appropriately evaluating non-lethal tools.

The important role of private wildlife organisations in facilitating scientific research: A case study of the Australian Dingo Foundation

As we enter an era of global mass extinctions, it is important to tackle wildlife research and conservation from multiple fronts, including those made available by wildlife organisations, zoos and sanctuaries. Captive studies are particularly useful when studying free-ranging populations is difficult, and/or when controlled conditions are required. Yet, despite the significant role that they play in supporting research and conservation of species and ecosystems, they are rarely recognised in the scientific literature. Here we present a case study of the Australian Dingo Foundation (ADF), a private organisation and captive breeding facility that actively supports research and conservation efforts relating to the dingo ( Canis dingo). Over the past decade (2010 to 2020), the ADF has facilitated research across eight research disciplines that include archaeology, behaviour, biology, cognition, evolutionary psychology, non-lethal management, reproduction and parental behaviour, and vocalisations. This has resulted in at least 21 published scientific studies which are summarised in this paper. As this case study demonstrates, captive facilities have the potential to contribute to the understanding and conservation of dingoes by providing practical alternatives to, and/or supplement studies of free-ranging populations. We conclude by outlining some of the implications and limitations of conducting research using captive dingo populations.

Perceptions of alien plants and animals and acceptance of control methods among different societal groups

Biological invasions are a widespread phenomenon and cause substantial impacts on the natural environment and human livelihoods. Thus, the European Union (EU) recently adopted Regulation No 1143/2014 to limit the negative impacts of invasive alien species (IAS). For implementing IAS management and policies, public support is highly and increasingly important, especially when it comes to charismatic species and lethal methods. Recognising the importance of the interaction of public perception with acceptance of IAS management methods, we used an online survey targeting three different stakeholder groups in Austria to evaluate potential differences in perception of IAS and management methods. In total, we received 239 completed responses: 20 nature users (farmers, hunters), 91 nature experts (conservationists, biologists) and 128 from the general public. Participants were more likely to accept lethal management methods when it was an IAS. Nature experts’ acceptance of IAS management methods was rather similar to those of nature users, while the general public preferred non-lethal methods. Chemical lethal methods (herbicides, poison pellets) received low rates of acceptance throughout all stakeholder groups, although nature users were more open to accept such methods for plants. Most respondents (> 50%) were not aware of the role of the EU in IAS topics nor did they know of the existence of the EUIAS regulation 1143/2014. However, more than 75% of respondents agreed that IAS measures and regulations should be implemented at EU level. This study shows that knowledge about native versus invasive alien status has an influence on the acceptance of management methods. Nature users may have higher levels of acceptance of lethal methods because they are economically dependent on extracting resources from nature. Invasive alien species regulations on EU level are generally acceptable, but there is low awareness for actions already undertaken EU.

Aerial baiting and wild dog mortality in south-eastern Australia

ContextWild dogs, including dingoes and dingo cross-breeds, are vertebrate pests when they cause financial losses and emotional costs by harming livestock or pets, threaten human safety or endanger native fauna. Tools for lethal management of these animals currently include aerial baiting with poisoned baits. In New South Wales (NSW), Australia, aerial baiting was previously permitted at a rate of 40 baits km−1 but a maximum rate of 10 baits km−1 was subsequently prescribed by the Australian Pesticides and Veterinary Medicines Authority. The efficacy of these baiting rates has not been quantified in eastern Australia, undermining the value of the policy and rendering adaptive management efforts difficult, at best. AimTo quantify the mortality rate of wild dogs exposed to aerial baiting at historic and currently approved rates, i.e. 40 baits per kilometre and 10 baits per kilometre, respectively. MethodsWild dog mortality rates were measured at sites in mesic north-eastern NSW, where aerial baiting was applied to control wild dogs and contrasted with sites and individuals where no baiting was undertaken. In total, 132 wild dogs were trapped and fitted with GPS-VHF telemetry collars before annual aerial baiting programs. Collars were used to locate animals after aerial baiting and to determine the fates of individuals. Key results90.6% of collared wild dogs exposed to aerial baiting at 40 baits km−1 died, whereas only 55.3% of those exposed to 10 baits km−1 died (Welsh’s t=4.478, P=0.004, v=6.95). All wild dogs that were not exposed to toxic baits survived during the same periods. ConclusionManagers using aerial baiting to maximise wild dog mortality in mesic south-eastern Australia should use 40 baits km−1 rather than 10 baits km−1. ImplicationsWild dog population reduction for mitigation of livestock and faunal predation requires the application of efficacious control. The currently prescribed maximum aerial baiting rate of 10 baits km−1 is inadequate for controlling wild dog populations in mesic forest environments in NSW.

Contested natures: conflict over caracals and cats in Cape Town, South Africa

In the mid-2010s, residents of Atlantic Beach Golf Estate (ABGE) in peri-urban Cape Town became embroiled in a dispute over how to respond to a wild predator, the caracal (Caracal caracal) killing domestic cats (Felis catus). It was revealing of the policy challenges posed by both these predators for urban ecology, of social conflict over notions of ‘nature’, and how cats can be framed as family members worthy of protection or as a danger to wildlife themselves. Conservation authorities resisted requests for permission to capture, remove or radio-collar and monitor any caracals on the ABGE, even after a caracal entered a home and killed a cat. This contrasted with Cape Town’s policy on Chacma baboons (Papio ursinus) where significant resources are allocated to reducing the spatial overlap between baboon home ranges and houses, and where negotiated protocols exist for the lethal management of individuals that persist in entering urban areas despite non-lethal deterrents. It also contrasts with the lethal management of caracals inside penguin (Spheniscus demersus) colonies. Policy towards the ABGE was shaped by its history as a security/eco-estate bordering a nature reserve, but the outcome—inconsistent policy regarding caracals that incentivises affected residents to take matters into their own hands—was sub-optimal for environmental managers, affected residents and caracals. Relatively high-income ratepayers committed to living with ‘nature’ (albeit curated) in places like ABGE are potential allies in assisting environmental officials better protect penguins and caracals, thereby facilitating more biodiverse ecologies with predators in urban Cape Town.