Hawksbill Turtles in the UAE: When Genetics Meets Conservation

We recently had the pleasure of hearing a lecture from Dr. Ada Natoli about how her study of the genetics of Hawksbill Turtles is contributing to conservation of the species in the UAE and the wider Gulf region.  

Dr. Natoli is a molecular biologist and professor at Zayed University, as well as the Founder and Director of the UAE Dolphin Project, a monitoring and education programme that has also received funding from the ENHG grants programme in the past.  

Her forensic genetics research is designed to glean specific knowledge about the population of Hawksbills in the Gulf, without which it is difficult to design effective programmes to protect them. Since all seven species of sea turtles world-wide are endangered, intelligent conservation is a must.

All images from this Time Out Abu Dhabi story featuring ENHG Co-Chair Arabella Willing

There are currently no population estimates for the Gulf region, despite nesting sites being present in Iran, KSA, Kuwait, UAE and Qatar.

Studying across the Arabian Gulf region is difficult for several reasons, Dr. Natoli continued. First, collaboration is weak across national bodies, and not all of the sites are continuously monitored—indeed, Abu Dhabi is the only site that has constant monitoring.

Though considered migratory, turtles are actually resident, but have been difficult to study, since a large part of their life cycle takes place away from shore. Once the vulnerable hatchlings make it to the ocean, they will not return for 30 years. That is how long it takes them to reach maturity and come back to their nesting site—and that is only females.

However, “assessing population boundaries is crucial to implementing effective conservation measures,” Dr. Natoli affirmed. She cited the Arabian Gulf humpback whale as a population that benefited from being recognized as genetically distinct. Until recently it was still not known that the Gulf humpbacks do not migrate, and so they hadn’t been included in other scientific efforts to conserve the species. Only 60-100 individuals were left after the ravages of Russian whaling in the 1960’s. They could easily have disappeared had Oman-based marine biologist Dr. Rob Baldwin not recognized that they were a special population that required specific conservation practices in place.

Accordingly, Dr. Natoli and her team set out with several questions regarding the Gulf Hawksbill population. First, how many males and females are there? Are the different nesting sites genetically distinct? Are juveniles from the same population?

 

They collected samples of at least 5 dead hatchlings from 67 nests across four winters, for a total of 418 samples. Using molecular genetic markers to investigate the population structure, they were able to ascertain:

·      Relatedness

·      Differentiation between populations

·      Population variability

·      Phylogenetic relationships—i.e. which hatchlings were born first

The samples were found to have 53 mothers over 67 nests. Despite the fact that some mothers nested more than once, they did not use different locations, and none of them were returning females. In Dubai and Abu Dhabi, the hatchlings had single paternity, whereas in the Sir Bu Nair site, they had frequent polygyny, perhaps pointing to different male stocks being present.

The findings were that there were clear differences in the Gulf among populations, and that they were strongly differentiated from the Seychelles populations. Interestingly, the team found that the Gulf population originated from one single founder!

Given the pressures from human activity on turtles in the Gulf and elsewhere, we hope that research such as Dr. Natoli’s can spur intelligent, cross-regional conservation programmes that can protect them in the years to come.  

If you would like to read a scientific paper written by Dr. Ada and her colleagues, please do so here.