For the moment the only steps we can take are to try to set up a breeding programme and possibly, in the long-term, start a re-wilding programme. For the latter, we would really need to know where they originally came from, to which (if any) living populations they are related, and if any other individuals of this type exist in captivity.
Professor Michi Hofreiter
Some Ethiopian lions have been noted for their large dark manes and compactness compared to other lions, but a paper which appeared in the European Journal of Wildlife Research
this week presents proof that they belong to a genetically unique population.
The team, headed up by scientists from the University of York
and the Max Planck Institute for Evolutionary Anthropology
, along with colleagues from Leipzig Zoo
and the Universities of Oxford
, has assembled conclusive evidence that the Addis Ababa lion is genetically distinct from all other lion breeds across Africa and Asia for which comparative data is available.
Lead author of the study Professor Michi Hofreiter, from the Department of Biology at York, spoke to ScienceOmega.com
about the importance of recognising the distinctiveness of the Ethiopian lion and what steps can and should be taken to ensure this rare breed does not die out. I began by asking what prompted the effort to prove the genetic uniqueness of the Addis Ababa lion. Professor Hofreiter explained that the project was initiated by the researchers from Leipzig Zoo.
"As well as having long-standing connections to the Addis Ababa Zoo, they had seen these lions and suspected they might be different, knowing their history," he said. "Hence they asked us if we could do the genetic analyses."
As far as the investigators know, the males at Addis Ababa Zoo are the only lions left to possess the distinctive long dark mane which characterises the Ethiopian subset of the species, Panthera leo
. There are just 20 lions in the collection of the capital’s zoo; 15 of these provided DNA samples for analysis in the study.
International collaboration was necessary in order to bring together the required expertise and provide access to the samples. Data from both mitochondrial and microsatellite DNA confirmed the hypothesis that the Addis Ababa lions are genetically and morphologically distinct from all other populations for which data are available.
"We needed to compare the Ethiopian lion data to the published data and for that we needed to re-analyse some of Carlos Driscoll's lion samples," stated Professor Hofreiter. "Also, we needed to work together with scientists and authorities in Ethiopia to get access to the samples. And then we wanted to have some lion experts (Ross Barnett and Carlos Driscoll) on board to make sure we got all the background right and did not overstep ourselves in the interpretations."
There is a paucity of information about remaining lion populations in the wild and in captivity; according to Professor Hofreiter, the genetic data on the captive population is to a large extent all the information we have. The researchers cannot be sure where the Addis Ababa lions came from as they are descendants of seven lions captured from the wild for Emperor Haile Selassie’s zoo in 1948 whose geographical origin is controversial.
Although it has been suggested that wild populations were hunted to extinction for their pelts, Ethiopian authorities have claimed that lions comparable to those in Addis Ababa Zoo have been sighted in the east and north-east of the country. It has so far not been possible to corroborate or refute these claims.
"The security situation in parts of Ethiopia – including the areas where the wild population is suspected – is very difficult, so it is almost impossible to make field surveys," Professor Hofreiter explained. "This means that the wild population may still exist or already be extinct; we simply don't know."
The researchers would like to see immediate action taken to prevent the Addis Ababa lion from following other populations, such as the North African Barbary lions and South African Cape lions, into extinction outside captivity. Across the African continent lion numbers are in decline, despite the fact that they remain the primary terrestrial predators.
Professor Hofreiter echoes lead author of the paper Susann Bruche, now at Imperial College London, in stating that a captive breeding programme is the imperative next stage in securing the Addis Ababa lion’s future. They believe that the results show enough genetic diversity among the remaining individuals to justify such a programme.
"For the moment the only steps we can take are to try to set up a breeding programme and possibly, in the long-term, start a re-wilding programme," he remarked. "For the latter, we would really need to know where they originally came from, to which (if any) living populations they are related, and if any other individuals of this type exist in captivity."
The question of where these lions originally came from is key, as Professor Hofreiter emphasised, but he detailed three further ways in which research could help the cause of conserving the Addis Ababa lion.
"Firstly, a comprehensive survey across all of Africa to know where there are still lion populations, along with genetic profiling of all existing wild populations," he stated. "Secondly, genetic profiling of the existing zoo populations would be interesting and finally, ideally, the same for museum specimens from all regions, including those regions where lions are extinct today.
"This would give us the necessary information to learn where to best protect lions and which zoo animals to use for breeding and potential re-wilding programmes; if it turns out there is a large wild population of the Addis-type lions still in the wild, a captive breeding programme is clearly less important. However, it would require a major effort and quite some money."