Bob and Sandy are two endangered green sea turtles that were rescued and brought to the Two Oceans Aquarium as part of our rehab-and-release programme. Sandy arrived at the Aquarium in September 2016 after being found stranded and badly injured by a boat's propeller. Bob was rescued in November 2014, found sick, injured and with a gut full of plastic litter. Under the care of Two Oceans Aquarium Conservation Coordinator Talitha Noble, their health and vigor have vastly improved.

But there are still some unanswered questions...

Determining the sex of a sea turtle is not easy. They show very few external sexual characteristics, and these only begin developing when the turtle reaches sexual maturity. For green turtles this can take as long as 20 to 35 years!

It's not as simple as doing a DNA test either (like we would for humans) as a turtle's sex is determined by the temperature at which its egg incubates - something we can't know when we receive these lost turtles so far from their hatching sites.

It is important for us to know a turtle's sex so that we can modify its diet and be aware of the implications of any behavioural or health changes we observe. Bob and Sandy are still quite young, so we needed to bring in the skills of a world-class expert to determine their sex.

Dr Brett Gardner, a consultant vet from Gauteng who had previously assisted us with treating Lady the moray eel, was brought in. One of his many talents is being able to determine the sex of young turtles via ultrasound, a rare skill.

The ultrasound machine was set up next to the I&J Ocean Exhibit’s medical pool and staff climbed in to draw Bob and Sandy's attention. While the turtles were distracted by love, food and attention, their rear ends were examined using the ultrasonic probe.

Based on internal structures, it is absolutely clear that Sandy is a female! You go girl!

Bob, on the other hand, is still too young to have his/her sex determined and the ultrasound results were inconclusive. Bob may still be a Bob-ara for all we know.