This post first appeared on August 31, 2011
Hurricane Irene, which hit the Abaco Islands a few days ago, had many people wondering about the fate of the critically endangered Abaco Barbs. The good news is that the three mares that are kept on the preserve are apparently fine. To my knowledge nothing is known about the fate of the stallions, but that has been true for a long time. There are at most two, and they are not kept on the preserve with the mares. The last sighting was of the 22 year-old stallion Hadar, made in February of this year. The second stallion, the splash overo Capella, has only been sighted twice in the last five years. A flyover of the island in 2010 did not turn him up.
Even without a hurricane, though, the future of this breeding group appears grim. No foals have been born since 1998, and the three remaining mares are believed to be infertile, possibly due to exposure to pesticides. But even if they were fertile, and the two stallions still alive and fertile, their small numbers would create dangerous levels of inbreeding. (Two of the mares are mother and daughter, so there are not even three distinct female lines now.)
From a color perspective, the splash overo pattern is still there by the slimmest of margins. If Capella, a homozygous splash, is still alive, then the prospect of preserving the pattern are much better. If not, probably the only source is the heterozygous splash mare Nunki. She looks very typical of splash carriers in breeds without sabino. The other two mares, Acamar and her daughter Alnitak, are plain bays. Acamar does have a star, and some splash carriers are pretty cryptic, but it would be slim hope were she the only one. Acamar and Alnitak do have frosty roaning in their coats, but it is not as pronounced as that on a dark-headed roan.
So the steps that must be taken now is to find one of the five horses still alive and still able to breed. If that can be done, out-crossing is going to have to take place. If experts are consulted, a preservation program can be created that would utilize animals from genetically similar backgrounds. That kind of research will be the subject of a future post, because it is a wonderful tool not only for preserving livestock diversity, but also for shedding light on the true relationships between the different breeds. The Barbs on Abaco may well be a cautionary tale – rather than a success story – about preserving genetically distinct populations, but there are many endangered groups where the outlook is more optimistic and there is still time to take action.
(Pictured is the Breyer Model Horse portrait of Capella, created to raise awareness of the plight of the horses on the island.)