One of the most immediate threats facing the Ethiopian wolf is disease, particularly rabies; three years ago a rabies outbreak killed 70% of the wolves in the Bale Mountains. The remaining animals were saved by an emergency injectable vaccination programme which was time consuming and unsustainable as the population begins to rebound. As a result the Ethiopian Wolf Conservation Programme is trialling an oral rabies vaccine on the Tarura pack.
Approximately three weeks ago EWCP administered oral rabies vaccines to as many of the pack members as possible. The next phase took place last week and involved trapping the wolves, taking blood (so that they could check that the antibodies were present), tagging and releasing them. If a wolf was caught that had not taken the oral vaccine then blood was taken for a baseline and the wolf received an injectable vaccination before being released. Claudio Sillero, founder and director of the EWCP was overseeing the process and of course we were on hand to document it!
Trapping an animal that is as intelligent as a wolf is not easy. The EWCP Programme Manager, Edriss Ebu, showed us how to set up a trap. First, a horse shoe shaped barrier of branches is erected. Halfway along the inside edge of the barrier, a piece of goat meat is staked down to draw the wolves in. Within the enclosed area, three foot traps are positioned and painstakingly covered with sifted sand so that they are invisible to the wolves. The aim is for a wolf to approach the bait and step on one of the foot-traps, which would then close around its leg and stop it from escaping.
Six traps were set up in the heart of the Tarura pack’s territory. Every 3 hours, day and night, for four days the traps were checked. This was a particularly arduous task in the freezing cold, pitch-black nights!
First to be caught were the inexperienced sub-adult (1 year old) wolves. In total, three sub-adults were caught. Only two adults were caught, the others were simply too canny and wary to be lured in by the traps.
When a wolf is found in a trap, a radio call is made to base camp. A whole multitude of people then scramble into a couple of Land Rovers and rush over the wolf. First of all a blanket is thrown over the wolf’s head which instantly calms it down. A vet then sedates the wolf and takes blood samples. The wolf is ear-tagged, weighed, measured and checked for injuries. After less than 15 minutes the wolf is ready to be woken up and released.
Often it turned out that the wolf is a recapture. In this scenario, the team simply check the wolf is unhurt and then released it. Since these wolves were not groggy from the effects of the sedative, when they were released they explode off at a spectacular pace!
It was fascinating to witness the efforts being made at the forefront of the fight to save the Ethiopian wolf. The team were satisfied with the number of animals that they were able to administer the oral vaccine to subsequently collect data from. Hopefully the trial will prove successful and a wide-scale vaccination can take place which will help make the wolves’ future a little bit more secure.
This is wonderful, what are they useing as the vaccine?
The vaccine currently being tested is a recombinant vaccine made from a living pox virus vector. The pox virus vector carries the rabies antigen in the form of rabies glycoprotein which is a protective sheath that surrounds the rabies virus. When the bait is swallowed it elicits an immune response without fear it will cause the disease because it contains only the non-infective surface proteins of the rabies virus. In order for the disease to actually replicate and cause infection the the viral nuclear material would need to be present, not just the proteins. The biggest worry is that the vaccine is temperature sensitive – the EWCP needs to find out if they can get the bait to the wolves in time for it to be effective.