THE NEEDLE IN THE HAYSTACK Continued…
STILL SEARCHING FOR A WHALE SHARK AGGREGATION ON THE GREAT BARRIER REEF
Following our exploratory expedition searching for whale sharks and manta rays in the far northern section of the Great Barrier Reef in late 2019 (see blog – biopixeloceans.org/far-northern-gbr-whale-shark-expedition), we undertook our second far north whale shark/manta ray expedition in December 2021, which was funded by Blancpain www.blancpain.com/en
In 2019, we spotted up to 13 whale sharks and satellite-tagged four. No manta rays were found. We came home from this trip feeling confident in our initial theory that there might be an annual aggregation of whale sharks in the northern GBR late in the calendar year, which corresponds to favourable environmental factors (e.g. currents, upwellings etc) and food availability.
The 2021 expedition has built on the 2019 success, by spotting over 20 whale sharks in 4 days. Five of these were satellite tagged, one was acoustically tagged, and tissue samples were collected from five whale sharks for genetic analysis, to be used in a global whale shark genetics project. Pictures of 10 individuals were also taken for photographic identification, noting that no individuals had been previously identified by other projects in Wildbook. (www.sharkbook.ai)
After the last expedition, we modified the clamps for attaching the satellite tags, in the hope that they will stay on for a longer time period, as the tags deployed in 2019 only stayed on for a few weeks to months. Currently, (six weeks after tagging) four of the five whale sharks tagged in 2021 are transmitting location data, with some interesting tracks. Tracks can be followed on OCEARCH and Citizen of the Great Barrier Reef marine life tracker (reeftracks.org).
The 2021 expedition was also our first success in collecting manta ray data for the far north GBR. We obtained identifying photos from six individuals (added to Project Manta database https://www.facebook.com/ProjectMANTA/), tissue samples for genetics from two, acoustically tagged one individual, and deployed two pop-off satellite transmitters (programmed to release in 6 months) – see blog on using PAT transmitters (satellite tagging) biopixeloceans.org/guide-tracking-tagging-part-3-3/
Two of the manta rays were tagged at Saunders Reef, the furthest north a satellite transmitter has ever been deployed on manta rays off the east coast, beating our previous tagging of one manta ray off Cairns. (Individual GBR I) https://biopixeloceans.org/manta-rays-northern-great-barrier-reef/
Following last year’s success, we are planning a more advanced expedition for late 2022, where we will collect information on environmental factors and food sources, to be analysed along with the whale shark and manta ray samples.
We feel confident we are close to finding the needle in the haystack!
Photos by Simon J. Pierce, PhD firstname.lastname@example.org
Co-Founder / Principal Scientist | Marine Megafauna Foundation
Marine Megafauna Foundation https://marinemegafauna.org/
Project Manta https://www.facebook.com/ProjectMANTA/
@Blancpain #Blancpain #BlancpainOceanCommitment #BlancpainFiftyFathoms #FiftyFathoms #Biopixel #Biopixeloceansfoundation #Whalesharks #Mantarays #Megafauna #Greatbarrierreef #Ocean #Oceanview #Underwater #Underwaterphotography #marineresearch #scienceforsolutions #sciencematters #fortheocean #BlancpainOceanCommitment