During June, 2010, the Central Rift veterinary unit was involved in ear-notching and fitting of transmitters to 10 black rhinos in Maasai Mara National Reserve. The exercise lasted for 1 week and was successfully completed. Other veterinary clinical intervention cases included the removal of a wire snare and treatment of a common zebra in Game farm, Naivasha and euthanasia of a zebra which suffered a complete compound fracture on the right hind leg in Mirera area, Naivasha.
Most wildlife species are still outside Maasai Mara National Reserve because of wet conditions and high grass levels in the reserve. The wildebeests have started moving into Maasai Mara from Serengeti, Tanzania across Mara river, the wildebeest migration is expected to peak by mid July leading to great influx of wild animals into the reserve.
BLACK RHINO (Diceros bicornis) EAR-NOTCHING AND FITTING OF TRANSMITTERS IN MAASAI MARA NATIONAL RESERVE:
As outlined in the 2007-2011 black rhino management strategy, KWS has put in measures to ensure that at least 60% of the black rhinos are identifiable by all. In order to meet this objective, KWS in liaison with Maasai Mara National reserve and Frankfurt Zoological society came together and planned for an ear- notching and transmitter fitting exercise for rhinos in the Maasai Mara National reserve. The target was to fit transmitters/ ear notch 6 rhinos and ear notch 4 rhinos making a total of ten (10) rhinos as identified by rhino monitoring teams.
Fitting of transmitters on 6 rhinos is meant to facilitate transboundary monitoring of rhinos as the Maasai Mara rhinos are free ranging and they roam to Mara Triangle and even to Serengeti. This will thus help monitor the movements and when the locations of the rhinos are mapped out, this will help the management of Maasai Mara National Reserve better manage the rhinos. The exercise took place from the7th – 11th June 2010.
MATERIALS AND METHODS
Kenya Wildlife Service – Rhino programme, veterinary section, capture section, Air wing
Maasai Mara game Reserve-Narok / Transmara management and rhino monitoring teams
Vehicles - 2 Land cruisers, 1 lifting crane
Aircrafts-1 Helicopter, 1 fixed wing
Others equipment included ropes, generator, drill, drill bits, dart guns, immobilization drugs and laboratory consummables.
The exercise composed of the ground team and the aerial team.
· Aerial team comprised of the fixed wing air craft pilot and a spotter to help locate the rhinos and direct the Helicopter which comprised of the helicopter pilot, darting vet and the spotter to help identify the candidates.
· Ground team comprised of the rhino monitoring teams, rhino programme personnel, veterinarians, laboratory technologists and capture team.
All the 10 rhinos were captured by chemical immobilization through darting from the helicopter using either Palmer Cap-Chur dart gun or Dan-inject dart gun. The dosage for immobilization drugs were 5mgs of etorphine hydrochloride combined with 80mgs of xylazine hydrochloride and 1,000 i.u of Hyaluronidase. All the efforts were made to ensure that the animals were darted on the thigh muscles to ensure an effective anaesthesia.
Monitoring of anaesthesia
Immediately after capture each rhino was administered with 10mgs of Nalorphine through the superficial ear-vein to enhance respiration, all the respiratory air ways were kept patent, the rhino blind-folded and ears blocked using gauze swabs to avoid light and noise irritations during anaesthesia. Water was used to control the body temperature during anaesthesia. Respiratory rate, body temperature and heart rate were monitored and recorded after every 5 minutes until the end of the operation.
The rhinos were ear-notched using sterile surgical blades and haemostats used to control haemorrhage after notching. The notch wounds and dart wounds were sprayed using an oxytetracycline spray to prevent any infection, enhance quick healing and to repel flies.
Fitting of transmitters
All the transmitters were switched on and tested to ensure that they are functional before fitted to the rhinos. Different sizes of drill bits were used to drill the rhino horn for lodging the transmitter and its aerial, dental acrylic paste was used to fill the horn and to cover the transmitter so that it remains in place before releasing the rhino.
Each animal was treated with 50mls of Betamox® antibiotic as a cover for any opportunistic bacterial infection. Opticlox eye ointment was applied into the eyes to prevent eye infection/irritation and to avoid desiccation of the eye-ball.
Biological Samples collection
Blood samples were collected from the dorsal superficial digital vein using sterile gauge 18 needles and 20ml syringes. Blood meant for serum was collected into plain tubes coated with clot retractor and whole blood was collected into EDTA coated tubes. Hair samples for isotopic studies were collected from the tails and kept into zip-lock paper bags. Tissue samples from the ear pinna were collected and kept in 70% alcohol in universal tubes. Ticks from the perineum, anal groove and inside the ears were collected and kept in 70% alcohol in bijou bottles. Feacal samples were collected from the rectum and will be processed for hormonal assay to assess stress levels and reproduction status in black rhinos.
Revival of anaesthesia
The rhinos were revived from anaesthesia immediately after ear-notching, transmitter fitting and samples collection. The animals were revived from anaesthesia using 24mgs of diprenorphine hydrochloride combined with 10mgs of atipamezole hydrochloride administered through the superficial ear veins. The animals rose up after about 2-3 minutes.
A total of 10 black rhinos were captured, ear-notched and or fitted with transmitters. Five (5) rhinos were fitted with transmitters. One male rhino on the Maasai Mara-Narok side named BETT was targeted to be fitted with a transmitter as it roams far and wide going as far as Maji Moto Area. This was meant to help monitor its movements. However, during the exercise, the rhino could not be located thus one transmitter was left behind to be fitted at a latter date when the rhino is sighted.
Capture and euthanasia of an adult male zebra with a fractured leg in Marera area, Naivasha
The zebra had been sighted by the Mirera area residents while limping and lifting up the right hind limb, it had a slight haemorrhage and was not able to join the rest of the herd due to pain and weakness. The residents reported this case to the District warden, Naivasha who informed the vet team to go and attend to the animal. By the time the vet was called, the animal had stayed with the injury for a few days and was unable to move and graze at the same rate with other zebras.
The zebra was captured by darting from a vehicle using 5mgs of etorphine hydrochloride combined with 80mgs of xylazine hydrochloride on the right hind thigh; it went recumbent after about 7 minutes.
The animal had suffered a complete open and compound fracture at the stifle (knee) joint region. It was extremely painful and infection had already set in. The cause of the fracture could not be established though it is suspected that it was knocked down by a vehicle along Mahi Mahiu – Naivasha road. The animal had no chances of recovery from the fracture so the vet team decided to euthanize it to alleviate prolonged pain and endless suffering. It was then euthanized and the carcass disposed in a nearby Mt. Longonot National park.
Treatment and removal of a snare from an adult male zebra in Game farm, Naivasha
This was an adult male zebra that had been sighted with a tight wire snare cutting through the fetlock joint of the right hind leg. The snare had cut through the skin and muscles inflicting a very severe injury on the leg, there was profuse bleeding as the wire kept on cutting through the leg muscles. It had stayed with the injury for some days and was unable to move and graze at the same rate with other zebras.
The zebra was captured by darting from a vehicle using 4mgs of etorphine hydrochloride combined with 60mgs of xylazine hydrochloride on the thigh muscles. The wire was immediately cut off using a wire cutter, retrieved from the wound and removed completely leaving an extensive raw wound on the limb. The resulting wound was then cleaned and treated using 10% hydrogen peroxide and a tincture of iodine applied topically on it using gauze swabs.
Revival from anaesthesia and prognosis
The animal was then revived from anaesthesia and released back to the wild after successful treatment. It had good prognosis after the removal of the snare and treatment because the bone tissues were still intact.
Despite heavy rains and impassable roads, the Mara veterinary unit responded to all the reported veterinary cases and with the support of KWS, FZS, DSWT and County council of Narok, the unit managed to complete the rhino ear-notching work which was scheduled early June, 2010. Kenya Wildlife Service greatly appreciates the support of David Sheldrick Wildlife Trust (DSWT) towards provision of prompt veterinary services to wildlife in Maasai Mara ecosystem, Central Rift region and Ruma National park.
Reported by; Dr. Domnic Mijele
DDBR&M, DDC&WS, DDS, AD-CR, SAD-BR&M, SAD-P & R, H-Other species, SW-NAROK, SRS-CR, DSWT.