International Whale Shark Day – How St Helena is significant in the global understanding of Whale Sharks
On International Whale Shark Day we join the global campaign for the preservation of our oceans largest fish and IUCN listed endangered species.
Reports say in the span of approximately 90 years ,Whale sharks have been re- categorised from ‘vulnerable’ (1928)to ‘threatened’ to ‘endangered’(2016) – edging them closer to extinction.
Efforts to study, preserve and safeguard the remaining populations have become critical as their protected status does not guarantee relief of uncontrolled tourism, targeted and untargeted fisheries and shipping.
For decades these gentle giants have graced the St Helena shores, and in recent years they have stirred a great deal of interest particularly in the fields of Science and Research.
In 2015 Dr Alistair Dove and a team of Marine Biologists from the Georgia Aquarium, Atlanta, USA were led to St Helena to discover what Dr Dove describes as a missing piece in the jigsaw puzzle of the global understanding of Whale Sharks.
The Georgia Aquarium team, headed by Dr Dove, have been focusing on whale shark research since 2005. Most of this research was carried out around the Yucatan peninsula where it is thought the largest aggregation in the world gathers.
Their studies elsewhere revealed that there were significantly imbalanced ratios of genders, juveniles and adults.
Using a variety of techniques including computer-aided photographic identification, laser calipers, acoustic array and several different types of tracking tags, the team began building up a picture of the St Helena whale shark community.
Over 30 Whale Sharks were tagged and dozens of photographs taken to assist the team in understanding where they go, how they grow, how they reproduce, and how St Helena fits into a global footprint for this species.
Having collated data over 3 visits, it was on their last trip in January this year that the G.A team revealed significant news at the first St Helena Conference.
Never before had any destination observe findings of equal adult gender ratio as found on St Helena, suggesting that St Helena is a key mating station.
Rare eye witness accounts of mating would validate this theory with observance also given to (rare) oceanic clarity, high local fidelity and no apparent obvious migration path.
“This makes us think St Helena may be important for the reproductive cycle” says Dr Dove, “which is a big deal because mating and birthing in this species have not been documented before.”
Following Georgia Aquariums amazing discoveries here, St Helena National Trust have subsequently secured £150k funding to the local whale shark research. Read all about it here.
Arriving on cue with the height of summer (January – March) whale shark encounters here are doubly unique.
Measures are in place to protect our marine species not least our treasured Whale Shark.
With only a handful of Marine operators conducting tours, whale shark encounters are strictly managed with controlled regulations and guidelines.
Seeing the Whale Sharks during their seasonal visit is not to be missed.
Marine tours are offered by a number of operators and can be booked through the Tourist Office.