Anna L. Meredith, MA, VetMB, CertLAS, DzooMed, RCVS, Specialist in Zoo and Wildlife Medicine
Royal (Dick) School of Veterinary Studies, University of Edinburgh Hospital for Small Animals, Easter Bush Veterinary Centre
Roslin, Midlothian, UK
When a wildlife casualty is presented to the general practitioner, rapid and important assessments and decisions have to be made, primarily to prevent suffering, but also in relation to staff health and safety and legislative requirements. Triage is the process of prioritizing patients based on the severity of their condition so as to treat as many as possible when resources are insufficient for all to be treated immediately. The term comes from the French verb trier, meaning 'to sort, sift or select'. True triage can be applicable to wildlife casualty situations, such as mass oiling incidents, but more frequently the practitioner is faced with a single individual animal; however the process of assessment and decision making is essentially the same. The process of dealing with a wildlife casualty can be divided into 6 stages (Best and Mullineaux 2003):
1. Initial location, capture and translocation
2. Examination and assessment for rehabilitation
3. First aid and stabilisation
5. Recuperation and rehabilitation
It is important that everyone involved with wildlife casualty work has a clear idea of what they are trying to achieve and why. There are complex moral and ethical issues to be addressed regarding if and when intervention is justified, and different people will have differing opinions on what is acceptable. However, in practice most vets are faced with a 'fait accompli' of an injured animal presented for treatment. The prime aim must always be to return an animal successfully to the wild. To do this the animal must be released with a chance of survival equivalent to that of other free-living members of its species. The alternatives are permanent captivity, which is rarely acceptable on welfare grounds, or euthanasia, which must always be considered at every one of the six stages listed above. Euthanasia, performed correctly, is not a welfare issue and it is often better to euthanize quickly and eliminate the possibility of further suffering, than to hold a wild animal captive and attempt treatment. Although members of the public frequently find this upsetting or unacceptable, it is an important educational opportunity to explain the reasons for any decision.
Why Bother? The Significance of Rehabilitation
To the Wild Population
Unless working with an endangered species, the rehabilitation of wildlife casualties will have little, if any, significant conservation value. However, it may involve some potential threats to the wild population either by the release of individuals carrying non-endemic pathogens, or by the release of non-indigenous species.
To the Individual
The significance of capture and treatment of an individual casualty is primarily one of welfare. If the disability is short term, requiring minimal treatment and stress, and the animal is quickly released back, then there are few concerns. However, if the disability is medium or long term, involving extended treatment and associated stress, with the possibility of the disability being permanent, then euthanasia is a very valid alternative. The welfare costs and benefits of intervention should always be assessed.
To the General Public
The general public will expect, and support, centres prepared to handle wildlife casualties.
As a Source of Information
The rehabilitation of wild animals offers the opportunity to gain information on different aspects of these animals and the environment where they live (e.g., environmental pollution, and infectious diseases).
Initial Assessment--Treatment vs. Euthanasia
Setting aside the philosophical arguments, a practical approach is to ask the following questions when coming to a decision:
Is it Possible to Treat the Animal?
Do you have the veterinary equipment and skills to deal with the injury/disease in this species? Most importantly, is the disease or injury treatable, such that recovery will not lead to permanent disability? You cannot cure an open fracture with necrotic bone, unless you amputate it. You may not be able to repair an eye that has been pecked by gulls. If an animal comes to you emaciated and collapsed, it is likely to have severe chronic underlying disease.
What Species Is It and What Is Its Behaviour in the Wild?
For a wild animal to be released back to the wild it has to have a chance of survival equivalent to that of other free-living members of its species. This means different things for different species: e.g., birds of prey need to be 100% fit with their full capability of flight, sight and grasping for hunting, while small passerines just need to be able to fly from bush to bush to eat and escape from predators. It is also very important to know if that species is migratory, if it lives in family groups, if it is very territorial etc.
How Long Will the Animal Have to be in Captivity? How Often Will it Have to be Handled for Treatment?
It is very important to appreciate that the animal is wild; it is not used to being handled or surrounded by humans or other pet animals. This situation is incredibly stressful for it, and potentially life threatening depending on the species (e.g., woodcocks and nightjars, which do not feed in captivity). This should be borne in mind when admitting a wild animal into captivity for rehabilitation (e.g., some birds of prey, pheasants frequently do not survive in captivity for longer than 1-2 days due to the stress).
How Old Is the Animal, and What Sex Is It?
Orphaned animals are often not true orphans. They are probably not injured or sick, and should not have been taken from the wild. It is essential that the animal does not become imprinted on humans. Some species are more prone to this than others: e.g., fox cubs, owl chicks, deer fawns. A very aged animal is likely to be at the end of its natural lifespan and is presented as a casualty because it cannot compete successfully for resources. A young adult may be being ousted by conspecifics and needs to find new territory. It is also very important, though not always immediately obvious, to know the sex of the animal. For example you cannot release a female bird that has a displaced fracture of the pelvis, as this could lead to egg binding.
Time of the Year?
Especially important in species which migrate or hibernate, and may mean prolonged captivity before release. If it is the breeding season, is the animal likely to have a bonded mate or dependent offspring?
Do I Have the Facilities? Are Rehabilitation Facilities Available?
Before admitting the animal, make sure you have room for it, and the necessary facilities to handle, house and look after it properly. You need at least a small area or room away from domestic animals to house wildlife, they should never be mixed. Large animals such as deer will need appropriate accommodation. Do you have sufficient knowledge on the biology and natural history of the animal to cater for it? Who will fund the animal's treatment? Once recovered, where will it go for rehabilitation prior to release?--some species, e.g., badger cubs, need highly specialised care and socialisation before release and this is not widely available. Contact with local wildlife groups/charities/ rehabilitation units with local knowledge and resources is often vital. It is pointless (and illegal in the UK under the Abandonment of Animals Act 1960) putting the animal through the stress of captivity and treatment to just release it into the wild without any consideration for habitat, competition, social structure etc. and so is unlikely to survive.
What Are The Risks to Personnel?
Is the animal likely to have a zoonotic disease and are there measures in place to minimise this risk e.g., bats and rabies (are staff vaccinated?), badgers and TB, hedgehogs and dermatophytosis. Are staff trained in how to handle the animal without getting injured?--e.g., herons and seabirds stab at the face, adders are venomous.
Are There Any Legislative Requirements?
These will vary from country to country. In the UK, although many species are protected under the Wildlife and Countryside Act 1981, veterinary surgeons are legally allowed to take them into captivity for the purposes of treatment until no longer disabled. Under the Destructive Imported Animals 1932 it is an offence to keep non-native species without a license, and to release them back into the wild, and this includes grey squirrels, mink and coypu. Similarly, under the WCA it is illegal to release species on Schedule 9 such as sika and muntjac deer and ruddy duck.
Any wildlife casualty will be highly stressed, whatever its injuries, by the process of capture, transportation and proximity to humans and an unfamiliar environment. Handling and intervention must always be kept to a minimum, and under anaesthesia or sedation if necessary to minimise further stress. Even animals with severe disease often do better under anaesthesia than being handled conscious because of this, and if gaseous anaesthesia is used, concurrent oxygen is also being administered. Injury risks to personnel are also minimised. The principles of first aid are the same for all species.
1. Trauma management:
a. Soft tissue injuries: haemostasis, cleaning of wounds and application of dressings.
b. Orthopaedic injuries: wing fractures in birds require immediate immobilisation of the wing as bone fragments (esp. humerus) can cause further soft tissue injury as it flaps. Fractures of the manus or either radius or ulna alone may only need support by taping together the primaries of the closed wing. Fractures of the radius and ulna require a figure of eight bandage to hold them against the humerus. Humeral fractures must be immobilised against the body by a figure of eight bandage that incorporates the body, leaving the other wing free. Dressings should only be left for 2-3 days as joints will rapidly stiffen when held in flexion. Leg fractures in birds can be splinted, or in large birds (tibiotarsus) supported with Robert Jones dressings. Femoral fractures are usually well supported by surrounding muscle and difficult to dress. Toe fractures can be supported by ball bandages. Limb fractures in mammals are dealt with as for domestic pets, but small mammals such as rodents may not require immediate support and a dressing may cause further trauma and displacement.
2. Fluid therapy: For most species, daily maintenance is 50ml/kg /day, but this is much higher in smaller species. Oral or parenteral fluids may be given depending on degree of dehydration. For practical reasons boluses may be necessary. Oral critical care formulas are available and are very useful. Lactated Ringer's or 4% glucose and 0.18% saline can be used intravenously.
3. Analgesia: This is a vital part of first aid. Most wildlife casualties will not exhibit overt signs of pain, due to a preservation reflex. All of the commonly available NSAIDs and opiates can be used and published dose rates are available.
4. Maintenance of body temperature.
Once stabilised, further diagnostic tests and specific treatment can be instituted. It is important to continually assess progress in order that welfare is not compromised. This includes response to captivity, such as willingness to feed, as well as the disease or injury under treatment. Assessment of the significance of any disease process must ensure that the disability is likely to resolve, that treatment will not expose the animal to excessive pain or distress and that it will be able to be released.
1. Best D, Mullineaux E. (2003). Basic principles of treating wildlife casualties. In: BSAVA Manual of Wildlife Casualties. Eds. Mullineaux E and Best D. BSAVA Publications: 6-28
2. Kirkwood J, Best R. (1998) Treatment and rehabilitation of wildlife casualties: legal and ethical aspects. In Practice 20: 214-216
3. Cooper J, Cooper ME. (2006) Ethical and legal implications of treating casualty wild animals. In Practice 28:2-6