Abstract

Following the closure of Marine Land of South Australia by the government, it was necessary to transport the 5 adult dolphins and 1 calf to SeaWorld in Queensland.

Many problems were anticipated as these animals had only experienced a minimum of handling and restraint. Some of the dolphins were old, two having been in captivity for about 23 years, while the other four had been born at Marine Land. The calf was less than 6 months old.

The preparations undertaken included the retraining of the dolphins to enter holding pens willingly. It was necessary to catch each animal and record its morphometrics for the construction of slings and transport crates.

Other planning considerations related to the dimensions of aircraft pallets and trucks and the personnel required to look after the dolphins and provide security.

The health status of the dolphins was monitored by blood sampling, before, during and after transport. All the dolphins (except the calf) were given Diazepam orally prior to capture and fed a mini transmitter to record core temperatures. Respiration and heart rates were monitored and general attitude was noted.

Introduction

Dolphin transport has occurred on many occasions but little has been written about the precise methods employed. In this particular instance there were additional problems posed by the intractability of the animals, their lack of handling and the ages of the dolphins especially the 6 month old unweaned calf. We were not at all confident of success.

Materials and Methods

Every effort was made to improve the responses of the dolphins to handling, mostly by increasing the utilization of the holding pens attached to the pool.

Each adult animal was caught and its body measurements taken so that individual transport crates and slings could be made for each animal. A double crate was made for the female dolphin and her 6 month old calf. The crates were constructed of marine plywood and were watertight.

A sump was provided at one end of each crate so that fresh water could be pumped or sprayed over the dolphin as needed during the transport. A knapsack spray was also attached to the crate in case extra water for cooling was required. Sea water was not used during this exercise to minimize any possible damage to the aircraft from spillage. It was also felt that the dolphins might be less stressed if fresh water was used.

The handles of the slings fitted into cut-outs at the ends of the crate so the dolphin was resting in the sling and supported on thick foam mats on the floor of the crate. Each sling had its own rope jig clipped to the handles to enable the sling to be lifted by a mobile crane. Digital electronic scales were inserted between the sling and the crane when the dolphins were weighed. External dimensions and fittings were designed to facilitate easy handling by forklift or crane and to comply with the size requirements for aircraft pallets.

Monitoring of Animals

Five days prior to the anticipated transport each dolphin (with the exception of the calf) was tranquillized with diazepam orally (dose-approx. 3mg/Kg). The diazepam was administered as powder placed in feed fish and fed to the animals 2.5 to 3.5 hours before capture. The dolphins were left undisturbed (except for observation of respiratory rate and behaviour).

In order to get the dolphins into the holding pens, it was necessary to draw a net along the length of the pool and release the dolphins not required. Once in the holding pen each animal was caught, restrained, weighed and a blood sample collected. A final fitting of the sling was also undertaken.

The dolphin and its sling were placed in the crate to make sure that everything worked and fitted correctly. The procedure was timed so that the loading would go according to the planned timetable.

The blood samples were analysed to establish "normals" for each dolphin. The behaviour of each dolphin was used to readjust the individual dosages of diazepam for the transportation.

The adult dolphins were fasted for 24 hours prior to transport.

On the morning of the transport day at about 0505 hours each adult dolphin was fed its dose of diazepam and a thermistor (Mini-Mitter Co., Sunriver, Oregon) for monitoring core body temperature. The dolphins were left quietly swimming.

The first animal was captured at 0734 hours, the pool water temperature was 17.5 C. As each dolphin was loaded into its crate the operation of the thermistor was checked.

Individual monitoring of body temperature, heart rate and respiration rate began when the dolphin was installed in its crate and continued at 10-15 minute intervals throughout the journey. Water temperature was also recorded. All animals were loaded onto the trucks by 0849 hours. Two handlers were assigned to each dolphin and a veterinarian was provided for each pair of dolphins. Cooling of the animals was achieved by electric pump sprays delivering water as needed and calico sheets were on hand if required for additional protection from the sun.

Results and Discussion

The adjusted doses of diazepam seemed to have a better calming effect on the animals when it came to catching them. However, BUTTONS still proved difficult to capture and restrain. When she was placed in the crate she thrashed about in the sling throwing her head up and down and from side to side. BUTTONS settled a little when the calf (SHASA) was placed alongside her in the crate.

The respiratory rate of the dolphins was between 1.5-2/min. after tranquillization and before capture. Apart from an increase immediately post-capture, the respiratory rate remained relatively constant, notable exceptions were BUTTONS whose rate was 7/min. on crating and TUFFY had a rate of 8/min. during blood collection at Adelaide airport. Generally, respiratory rate returned to normal during the flight with an increase as the descent began.

Body temperatures ranged from 35.0-38.0 C at loading. The dolphin's temperatures reacted quite differently to the transport, some rising initially and stabilizing while others rose and remained elevated. We had not recorded the dolphin's temperatures previously and are unable to report whether the observed changes are significantly different from normal.

Skin temperatures were measured at the base of the dorsal fin of several animals but were some 10 degrees C lower than body temperature and were difficult to correlate to either the body temperature or the physical state of the dolphin at the time.

Water temperature in the crates increased slowly during the transport. The increase was from 17.5 C to 21.5 C. This was not unexpected as we travelled from latitude 35 S to 28 S. Air temperature on the aircraft was maintained at 19.4 C.

Heart rate proved to be the most useful parameter monitored for assessing the health status of the dolphins during the transport. When the animals were stressed or handled the heart rate increased in some instances up to 2.5 times the resting rate. Again different individuals reacted differently.

TUFFY's heart rate was elevated from 80 to 100 beats/min.(bpm) after capture and loading into the crate. He settled to 75 bpm in 30 minutes, but rose to 120 bpm during a protracted blood collection. TUFFY's heart rate increased again as the aircraft began its descent and during landing and unloading.

CHEEKY exhibited an elevation of his heart rate after capture, whilst unloading and while waiting to be removed from the truck at SeaWorld. CHEEKY had maintained a continual low vocalization throughout the flight but was otherwise apparently stable.

REBEL was disenchanted with being caught and transported, his heart rate nearly doubled following capture and remained somewhat elevated for the duration of the transport. His normal heart rate of 60-65 bpm rose to 90 bpm as the trucks started to move, when he had a blood collection and to 78 bpm as the aircraft began to descend.

SALTY's heart rate went up to 108 bpm at crating and remained over 80 bpm until she was off-loaded onto the truck at Coolangatta.

BUTTONS maintained a heart rate of 60-63 bpm in spite of all her struggling and thrashing about - until she was loaded onto the aircraft. Her heart rate then rose to 105 bpm and stayed over 92 bpm till we arrived at SeaWorld. She was relatively stable in her behaviour during the flight though she did move backwards in the sling. BUTTONS had continual slow movements of her tail flukes throughout the exercise. There was an additional problem at the Coolangatta airport when the crate containing BUTTONS and her calf (SHASA) was placed on the truck so that the dolphins were facing/travelling backwards.

SHASA had a "resting" heart rate of 60-65 bpm during this exercise. The responses to manipulation and other changes were dramatic. When the crate was loaded onto the truck the calf's heart rate increased to 150 bpm, it settled once the trucks were mobile, but rose to 105 bpm when the calf started thrashing around as the aircraft began to move. There was another rise when the calf slid back in the sling and as the aircraft started to descend. The inadvertent loading of the crate containing SHASA and BUTTONS so that they were travelling backwards from Coolangatta to SeaWorld had a profound effect on the calf. SHASA became very agitated and distressed, flicking the tail flukes vigorously every 20-35 seconds, respiration rate increased to over 3/min. and the heart rate hovred between 108 and 132 bpm. On arrival at SeaWorld, SHASA settled and swam off with BUTTONS following their release into the new pool.

The results of blood sample monitoring are reported elsewhere in this volume.

All adult dolphins were given intramuscular injections of long acting oxytetracycline, vitamins B complex and B12 prior to unloading at SeaWorld. SHASA received a long-acting injection of penicillin/streptomycin with the multi-vitamins.

Conclusion

The dolphins travelled much better than expected and arrived in quite good condition. All adult dolphins (except TUFFY) fed normally within 2 hours of release to their new pool. The calf was observed in a suckling position with BUTTONS.

This translocation operation was a success, due in no small part to the teamwork of the personnel and the meticulous planning from the outset.

Acknowledgements

1.  To Stuart Anstee for most of the planning and Organization

2.  To Ian Hobbs for the financial and logistic arrangements

3.  To the animal attendants - Nick Kirby, Tracey Haslett, Graham Ross, Colin Cock

4.  Terry Martin, Peter Masters, Narelle Rowland and Kevin Gliddon

5.  To veterinarians - Nick Gales, Graham Phelps and Mark Hill.