Stress and Capture Myopathy in Hares
28 January 2005

Updated report highlighting capture myopathy, a stress-induced condition which has been identified as posing a threat to the hare species. Hares captured from the wild and used in coursing are among the animals most at risk.

Stress and Capture Myopathy in Hares
by Mike Rendle of the Irish Hare Initiative

Introduction

Capture myopathy (alternative names include post-capture myopathy, stress myopathy and transport myopathy) is a little-studied condition that has been recognised in a number of wild animals and domestic rabbits for some time. In recent years some work has been carried out in the context of hunting and coursing, where the use of dogs or snares cause high levels of trauma before death or capture.

There is now compelling evidence that the well being of hares, and ultimately their survival, is compromised by capture, handling and transport etc. This has ethical and practical implications for researchers, veterinary professionals, carers, conservationists and field sports enthusiasts.

Definitions

Welfare of an animal has been defined as "its state as regards its attempts to cope with its environment (Broom 1986; Broom & Johnson 1993). Thus welfare refers to the state of an animal at a specific time and can be good or poor irrespective of what people think about the moral or ethical use of the animal concerned. If the individual is having difficulty in coping with its environment, or is failing to cope, then its welfare is poor (Broom & Johnson 1993; Broom 1996). Since this definition of welfare refers to the state of an animal, we should be able to use measurements of that state to indicate welfare and Bateson (1997) has argued that the animal should be given the benefit of the doubt as regards the existence of anxiety, suffering and pain. Animal welfare science is a scientific discipline, which has developed rapidly in recent years. Much of the research has been carried out on domestic animals but the basic methodology is the same for all species including wild animals (Broom 1999)." ¹

Stress is the sum of the biological reactions to any adverse stimulus, internal or external, that tend to disturb the homeostasis of an organism. The need to minimise stress should be self-evident simply because of the problems related to it. Stress alters the "normal" physiology of an animal and can induce a pre-pathological state. In a prolonged situation of stress, the pre-pathological state provides an opportunity for the development of pathologic change. Stress is usually caused by excessive exertion or fear during translocation. The many unfamiliar events that occur during this procedure lead to both psychological stress as well as the physical stress of muscular exertion. This exertion may result in damage that can lead to development of a pathological state.²

Capture sympathy is an important stress induced condition, most frequently encountered in wild animals. It frequently occurs following prolonged and intense chases or manipulations. The proximate cause for capture myopathy is probably a combination of fear and anxiety accompanied by muscle exertion.² Fear is the single most important factor in capture myopathy.³

Clinical Manifestations

There are four categories of capture myopathy according to the way the condition presents itself. These are PERACUTE, ACUTE, SUB-ACUTE and CHRONIC. There are few post-mortem signs.³

PERACUTE CAPTURE MYOPATHY
Death may occur suddenly or in a matter of minutes.

ACUTE CAPTURE MYOPATHY
This is a less severe form of the above with the animal lingering before death. Death occurs in 24 - 48 hrs.

SUB-ACUTE CAPTURE MYOPATHY
Again a less severe form of the above. Death takes a few days.

CHRONIC CAPTURE MYOPATHY
These animals live for several days or months but their ability to survive may be compromised.

Treatment

There is no treatment for this condition,³ however, it may be prevented by effective risk assessment, best practice and by applying the Precautionary Principle. (See recommendations)

Hare Coursing

The link between enclosed hare coursing and the factors responsible for capture myopathy is indisputable. In Great Britain and Ireland, the most common sufferers of capture myopathy in the wild mammal fraternity are deer and hares.⁴ Rabbits, which are also members of the Leporidae family, may die suddenly when stressed ⁵ or succumb to life threatening illness such as stress enteritis.^6,7 Both hares and rabbits have been known to die of cardiac arrest brought on by stress or fear of being caught ⁸ and it is likely that hare coursing or other hunting with dogs will cause very poor welfare in hares.¹

In Ireland, where enclosed hare coursing takes place, these outcomes are very apparent. The trauma has been documented by the coursers themselves.⁹ The Irish Coursing Club's veterinary surgeon, JJ O'Sullivan, states that

"it is impossible to completely avoid stress in hares once you manhandle them, and take them out of their natural environment. Stress can come in many shapes and forms and as long as you have the hare in captivity, he is prone to it - resulting in his disability and even death at times. I believe a lot of damage can be done to hares by rough handling and netting."

Mr. O'Sullivan goes on to elaborate on causes of stress of netted hares as follows:

"Stress can start from the very minute you get him out of his form until you land him in the net, followed by rough handling, boxing and transporting. Sudden environmental changes such as fluctuating temperatures and varying humidity - being hot and sweating in a bag and later over-crowded in boxes. Changes in diet from a high roughage diet in nature, to a sudden very concentrated grain diet with little fibre in captivity. Injuries and stresses from crashing into each other in the paddock, whether caused by well meaning committee members during the day or while being chased and harassed by dogs or cats at night. Adverse weather - unless you have adequate shelters provided, any sudden changes in climate can result in an outbreak of pleurisy or pneumonia with the possibility of turning what could be a good meeting into a disaster."

Jerry Desmond, Chief Executive Irish Coursing Club is on record ¹⁰ as saying

"When hares get injured, they find it very difficult to recuperate from any form of injury."

Professor Donald M. Broom, Professor of Animal Welfare, University of Cambridge states that

"When a mammal like a hare is chased by a predator like a dog, it will show physiological changes associated with extreme fear. These include greatly elevated heart rate and high levels of emergency adrenal hormone production as well as other changes in hormone levels and enzymes. Extreme responses like those shown when chased by a predator can result in reduced life expectancy due to the immediate dangers of injury during very vigorous activity and greater risk of cardiovascular or other breakdown as a consequence of the response. We must conclude that, whether or not the hare is caught, its welfare is very poor during the chase and for periods afterwards which will be prolonged in some cases."

In November 2002, researchers from Queen's University Belfast carried out an 11- week study ¹¹ of eight Irish hares (Lepus timidus hibernicus) that had been netted, kept in captivity and used for enclosed coursing. After coursing, radio-collars were attached and the animals were radio-tracked after release. All hares radio-collared were judged to be good condition by the attending veterinary surgeon. During the study period two hares died, both within 11 days. Although one had been eaten, the cause of death of both specimens was not determined. Given that both hares were adults in good condition, the timescale and circumstances of the deaths are consistent with sub-acute or chronic capture myopathy.

In December 2003, 83 hares were captured and coursed at an Irish Coursing Club meet in Wexford. On that occasion 40 hares died, a mortality rate of 48% ¹⁴

The dead hares were examined by veterinary surgeon, Dr Peter A. Murphy PhD, MVB, MRCVS.¹⁵ A number of pathogens were identified in post-mortem examinations ¹⁶ and Dr Murphy says in his report, 'under the influence of stress, the hare's immune system is compromised and these organisms suddenly multiply rapidly to cause a severe clinical disease and untimely death. Hares being normally solitary animals are significantly stressed when corralled and coursed, and this combination of circumstances has resulted in the deaths in this case'.

Conclusion

It is widely acknowledged that Irish hare numbers are low ^12,13 and that they have become locally extinct in some areas. ^7,12 There is no evidence that hare coursing makes any positive contribution to Irish hares or their numbers, however it continues to target those areas where the remaining vulnerable populations still exist. On balance, any activity that may result in capture myopathy, such as hare coursing, must be regarded as a threat to the species.

Recommendations

• Capture myopathy should be brought to the attention of relevant persons who should be encouraged to become familiar with current guidelines and best practice.
• When the capture or handling of hares is necessary, it should be kept to a minimum and in line with current best practice. A stress-free environment should be provided.
• The precautionary principle should be applied when assessing any policy or proposal that may involve capture, transport or handling of hares.
• Legislative, advisory and professional bodies should take account of the negative impact of activities that may result in capture myopathy when reviewing, planning or implementing policy.
• Law enforcement and environmental protection agencies should proactively enforce relevant legislation.

References

1 An independent review of the scientific literature prepared by Professor D M Broom and the Cambridge University Animal Welfare Information Centre
2 Adi Golos, Stress & Capture Myopathy In Wild Animals (Hebrew University of Jerusalem)
3 Jeff Fyffe BVSC MRCVS MACVSc, Capture Myopathy
4 Les Stocker, 2000, Practical Wildlife Care, Blackwell Science, ISBN 0-632- 05245
5 Virginia Richardson MA VetMB MRCVS, 2000, Rabbits; health, husbandry and diseases, Blackwell Science ISBN 0-632-05221-X
6 Author's personal observation
7 Anecdotal evidence
8 Les Stocker, 1992, Wildcare Handbook, Chatto & Windus Ltd. ISBN 0-7011-3775-4
9 JJ O'Sullivan MRCVS, Some Thoughts on The Feeding and Management of Hares - The Abbeyfeale Experience
10 Broadcast on Morning Ireland, RTE, October 1991
11 Preston et al, 2003, Survival and dispersal of coursed Irish hares in Northern Ireland (QUB/EHS)
12 Dingerkus & Montgomery, 2002, A review of the status and decline in the abundance of the Irish Hare in Northern Ireland (QUB)
13 The Decline of the European Hare - An interdisciplinary European Research Task, 2001
14 Internal Dúchas report, 9th January 2004
15 Veterinary report by Dr Peter Murphy MRCVS, 7th January 2004
16 Post-mortem reports, Kilkenny Regional Veterinary Laboratory, 6th January 2004

About the author: Mike Rendle has been an active environmentalist for over twenty years. He has a special interest in Ireland’s endangered mammals. An enthusiastic bat worker, Mike identified the newest mammal to be found in Ireland, the Nathusius’ pipistrelle. He is currently co-ordinating an initiative helping to conserve one of our oldest mammals, the Irish hare.

More information can be found at www.irishhare.org.

A hare lies dead inside a coursing enclosure. One possible cause of death was capture myopathy, a condition which constitutes a threat to the Irish hare species as a whole. Capture myopathy is explained in a report by Mike Rendle of the Irish Hare Initiative.