METHODS OF REHABILITATION, RELEASE AND POST-RELEASE MONITORING

2.1 The role of wildlife carers

Thousands of individuals are involved in wildlife care throughout Australia. Many are part-time carers, but a substantial number do it full-time and have done so for many years and are skilled and experienced carers (Haering et al.

Five main motivations for people becoming wildlife carers have been identified (Pokras 2002; Parsons 2007):

• Welfare: caring for animals to relieve pain and suffering

• Environmental: redressing the damage caused by human activities

• Educational: educating the community about wildlife

• Scientific: obtaining information about the biology, health and conservation of wildlife

• Egotistical: a means of providing the wildlife carer with status in the community.

Dubois and Fraser (2003) found similar motivations in their study of three stakeholder groups involved in wild­life rehabilitation: wildlife carers, veterinarians and gov­ernment officials. They assumed that because these groups had different education, experience, training and skills, their perceptions, motivations and goals of wildlife rehabilitation would also be different. However, all three groups identified their main motivations and goals as the ‘humane care of wildlife until release or euthanasia’ and ‘public education and awareness’.

In summary, these motivations indicate that wildlife carers have a strong commitment to wildlife care, which commonly leads them to make significant personal sacri­fices (DSE 2011).

Most wildlife carers start with little experience or training in wildlife care. Thrune (2002) believes that they take it upon themselves to learn as much as they can to improve their skills to become effective and successful wildlife carers. This involves species identification, life history, behaviour, housing, nutrition, handling and restraint, medicine and euthanasia among other disci­plines.

In addition, licenced wildlife rehabilitation organisa­tions and shelters have been established in several parts of Australia and provide training courses related to rescuing and caring for native animals, thus retaining a large body of knowledge among their members. These wildlife organisations and shelters function as a well-established network where there is a constant exchange of informa­tion to increase and improve the skills and success of their members (Parsons 2007).

2.2 The role of veterinarians

Veterinarians are fundamental in wildlife rehabilitation (Tribe and Hanger 2005a). They have important respon­sibilities in relation to treatment, prescription and use of scheduled drugs by non-veterinarians, euthanasia, wel­fare, disease risk assessment and the protection of human health. They are also responsible for providing evidence­based advice to wildlife carers, the public and govern­ments (Vogelnest 2008). Veterinarians experienced in wildlife care should be involved in the development or improvement of policies and procedures regarding wild­life rehabilitation (Sikarskie 1992).

Although wildlife carers can examine an animal and provide first aid, all animals coming into care should be examined by a veterinarian (DEHP 2013) as most present with injuries or disease. Others may become ill during rehabilitation and will require additional veterinary assessment (Tribe and Hanger 2005a). Early assessment to establish a prognosis and suitability for rehabilitation and release is essential to avoid unnecessary stress and suffering for the animal (EPA 2007; Vogelnest 2008).

Using Qld legislation as an example, the Veterinary Surgeons Act 1936 states that only veterinarians are trained and qualified to diagnose and treat diseases or injuries and licenced to prescribe and administer certain drugs or perform anaesthesia and surgery.

Veterinary involvement in other procedures such as pre-release assessment, euthanasia and necropsy are also important. Ideally, all rehabilitated animals should be subjected to a health assessment by a veterinarian before being released to the wild (Vogelnest 2008). Regarding euthanasia, the Qld legislation, for example, states that wildlife euthanasia should be performed by IV, IC or IP barbiturate overdose while the animal is under general anaesthesia and this must be administered by a registered veterinary surgeon. When this method is not available other methods appropriate to the species can be applied (DEHP 2013). Necropsies should ideally be carried out by veterinarians, but if this is not possible, a basic necropsy performed by an experienced carer under the guidance of a veterinarian can also provide valuable information on the cause of death of an animal (QWRC 2008).

2.2.1 The private practice veterinarian

Veterinarians in private, domestic animal practice are often presented with diseased, injured or orphaned wild­life (Haering et al. 2021). Although undergraduate veteri­nary education in Australia covers topics in wildlife medicine, the quality and quantity varies among institutions (Boardman 2016). Therefore, many veteri­narians are likely to be underprepared for dealing with wildlife patients. However, in a recent survey of 132 vet­erinary practices across Australia, the scale of the involve­ment of private practice veterinarians in treating wildlife became apparent: 82% of respondents indicated they saw less than 10 wildlife cases per week, with the estimated median being between 5 and 10 cases per week (Orr 2017; Orr and Tribe 2018). These figures may appear under­whelming; however, this would give an annual wildlife workload of ~ 260-520 cases per veterinary practice.

In a survey of private veterinary practices in the United Kingdom, Barnes and Farnworth (2017), found that costs and time were the major restrictions to veterinarians treating wildlife. A survey of Australian veterinary prac­tices found similar results, although time and knowledge/ skills were nominated as the most prohibitive barriers to the veterinary treatment of wildlife (Orr 2017).

Much of the wildlife work performed by private vet­erinarians is pro bono, with 56% of respondents indicat­ing that they never receive reimbursement for wildlife treatment and 34% responding that they rarely receive reimbursement. Of the clinics that did receive reim­bursement for wildlife costs, an overwhelming majority reported less than 10% of the costs for wildlife treatment covered (Orr 2017).

A consistent recommendation by wildlife veterinarians to improve wildlife welfare is to assess wildlife presenting at clinics as promptly as possible (Tribe and Hanger 2003; Tribe and Hanger 2005b; Vogelnest 2008; Mullineaux 2014). The Australian veterinary practice survey found that more than 74% of respondents only assess wildlife ‘whenever we have a spare moment’, as opposed to the 20% that indicated they assessed wildlife ‘immediately upon presentation’ (Orr and Tribe 2018). This perceived lack of time expressed by clinics regarding wildlife assess­ment and treatment is a major welfare concern, as an esti­mated 73% of wildlife present at veterinary practices for trauma (Orr 2017).

Prompt assessment is the first step in the rehabilita­tion pathway. Prognosis, suitability for release and the animal’s welfare should be evaluated frequently by veteri­narians, from initial presentation, during care and finally at pre-release checks (Tribe and Hanger 2003; Hall 2005; Vogelnest 2008; Grogan and Kelly 2013).

The euthanasia of wildlife can be both technically and ethically challenging. Unfamiliarity with the anatomy, physiology and restraint can make selection of euthanasia method difficult. However, resources providing this information are available and describe the methods in detail (Fig. 4.1) (Tribe and Hanger 2005b; AAZV 2006; Pollock 2006; Vogelnest 2008).

Practice owners or managers should develop policies or procedures to ensure that wildlife patients are dealt with promptly and appropriately (AVMA 2017). Not to provide prompt assessment, accurate diagnosis, appro­priate and adequate treatment (including analgesia), referral to a specialist wildlife veterinarian or hospital or euthanasia is a failure of a veterinarian’s duty of care. There is also the need for accurate record keeping, as these records provide documentation of treatments, assist with future release considerations, allow veterinarians to account for time and expenditure on wildlife cases and may be required as evidence in the event of litigation in relation to the circumstances leading to the need for treatment or the care provided (Vogelnest 2008; RSPCA UK 2010).

2.2.2 Wildlife hospitals

Wildlife hospitals primarily focus on triage, treatment or euthanasia of wildlife, ensuring the immediate and ongoing welfare of individuals is addressed. Addition­ally, they act as centres for research, education and fund­ing. In Australia, wildlife hospitals operate under a diversity of funding models. Some are funded and oper­ated entirely by state government departments, while others are run by state funded organisations such as zoos, are university funded or supported by non-govern- ment organisations.

Analysis of admission data for several wildlife hospi­tals in south-east Qld has been undertaken (Bouchon- Small 2013; Burton 2014; Burton and Tribe 2016; Taylor-Brown et al.

Fig. 4.1. Decision tree for the assessment of wildlife in clinics (adapted from AVMA 2017).

Wildlife Hospital (RSPCA) and Currumbin Wildlife Sanctuary Wildlife Hospital (CWSH). These three hospi­tals service the fastest growing urbanised population in Australia, with intake data reflecting the impact of urban development on native wildlife. In 2012, over 17 000 wildlife cases were seen across the three hospitals, with annual increases in the number of wildlife cases present­ing since 2010. Trauma (other than domestic animal attack) was the most common reason for admission. Other frequently cited reasons for presentation included domestic animal attack, illness, displacement and ‘unknown’ - by far the most nominated category (Bou- chon-Small 2013).

Over 50% of cases were euthanased, suggesting the welfare, prognosis, post-release survivorship and risk to free-ranging populations were assessed as poor in a large proportion of cases. In 20% of cases the animal was released, representing some 3500 animals (Bouchon- Small 2013). There was no post-release monitoring, so the outcomes for these released animals are largely unknown. Although the results of this study are limited by a lack of accurate descriptive histories, the information gained provides an insight into the admissions to wildlife hospi­tals in south-east Qld.

2.3 The wildlife rehabilitation process

When a sick, injured or orphaned animal is found by a member of the public, wildlife carer or government wild­life agency officer there are several key decisions to be made to determine the intervention required. These will depend on the species and the circumstances under which it is found (Fig. 4.2) (OEH 2011; Cope et al. 2022).

Fig. 4.2. Decision tree for the rescue, rehabilitation and release of wildlife (adapted from OEH 2011).

2.4 Release

In line with the definition and goals of wildlife rescue, rehabilitation and release outlined previously, release methodology and regular review are critical to success. However, post-release survival is largely unknown and dif­ferent release strategies have not been critically evaluated.

2.4.1 Pre-release considerations

Prognosis for release and post-release survival must be considered early and regularly reviewed throughout the rehabilitation process (Fig. 4.2). More specific consider­ations and prognostic indicators are summarised in Table 4.2 to guide decision making around suitability for treatment and release.

2.4.2 Post-release considerations

Post-release monitoring, where rehabilitated or translo­cated animals are tracked in the wild for a period after release, is the gold standard for determining survival and efficacy of rehabilitation and release practices (Guy and Banks 2012). This can be achieved in several ways, rang­ing from daily visual checks of feeding sites; camera trap­ping or live trapping; radio-telemetry or satellite tracking over a period of weeks to months; or application of bands or tags that facilitate identification and reporting should the animal be found alive or dead. In the handful of post­release surveys that have been conducted and published, mixed results were found, with variations in survival rates between translocated versus rehabilitated animals, release sites and species (Tribe et al. 2005; Ling 2014). Post-release monitoring of survival, fecundity, health, dispersal and home ranges has been undertaken for east­ern ring-tailed possums (Pseudocheirus peregrinus), common brush-tailed possums (Trichosurus vulpecula) and koalas (Phascolarctos cinereus) (Pietsch 1994; Augee et al. 1996; Tribe et al. 2005).

A useful indicator for successful rehabilitation is measuring survival through a pre-established post­release time frame. Additionally, evidence of reproduc­tive success of rehabilitated wildlife after release justifies the effort and resources invested (Leighton et al. 2008; Ratz and Lalas 2010). Substantial information regarding habitat use, dispersal, home range and breeding behav­iour can be obtained using telemetry (Tribe et al. 2005; Ratz and Lalas 2010). Assessing post-release survival and behaviour allows for assessment of the effectiveness of treatment and rehabilitation practices (e.g. pre-release conditioning techniques or for determining the effect of

Table 4.2. Considerations and indicators of poor prognosis for treatment, rehabilitation and release of wildlife (Vogelnest 2008)

Considerations and prognostic indicators

The animal has sustained such severe injuries that it is unlikely to survive even with treatment

The animal has sustained injuries that may be treated but will leave it with a disability that may affect survivorship once released

The animal is suffering from an infectious disease that may pose a risk to other animals during rehabilitation or to free-ranging conspecifics, sympatric species and ecosystems after release

Weak or sick animals of common species where there is no evidence of contributing anthropogenic factors and illness is associated with natural events (e.g. flying-foxes [Family Pteropodidae] in heat waves, starving eastern grey kangaroos [Macropus giganteus])

The animal is an orphan and the prognosis for successful return to its mother or hand-rearing is poor because of age, stage of development, resources required and potential for imprinting or development of other behavioural inadequacies that would affect survival after release

Lack of resources (facilities, personnel, finances, food, veterinary care, drugs) to care adequately for the animal

Geriatric animal

It is illegal to release an animal (e.g. eastern grey kangaroos in the ACT)

The animal is behaviourally unsuitable for release (e.g. imprinted or habituated to humans, lack of predator avoidance skills, lack of natural diet recognition and foraging skills) release techniques on survival [Holz et al. 2006]). When assessing post-release survival and behaviour to deter­mine the success of hand-rearing or rehabilitation, data should be compared with similar data from free-ranging populations (Hall 2005).

Lastly, post-release surveys can provide useful health data on a species in the wild. Released animals may be injured or be exposed to diseases and found sick or dead. Knowing the cause of the animal’s illness or death pro­vides valuable disease surveillance data for the species (Hall 2005).

3.