For the past five years, Cendrawasih Bay’s friendly whale shark population has been attracting a lot of attention, primarily because of the near-certainty of having outstanding (and lengthy!) whale shark encounters during a visit to the region. Unlike many of the other known whale shark aggregations in the world (such as Ningaloo, Isla Mujeres, Belize, Galapagos and Donsol), which are highly seasonal, we now know with certainty that Cendrawasih has whale sharks present in the bay year round. Indeed, based on our observations combined with photos submitted by visitors to our BHS whale shark database, some highly-recognizeable individuals seem to be present throughout the year. Of course, one of the surest ways to confirm this is to monitor individual animals’ movements through satellite tagging – which is exactly what we’ve been doing in collaboration with the Cendrawasih Bay National Park Authority and Pak Bram Maruanaya and his local Kalilemon homestay in Kwatisore.
Since June 2015, we’ve been able to tag 15 male whale sharks (ranging in size from 3 to 7 m in length) from Cendrawasih, using custom-made fin-mounted satellite tags by Wildlife Computers. These fin-mount tags have extended battery life which we hope will provide data for up to two years, and we’ve been delighted with their performance to date. All but one of the tags has been transmitting data very regularly (on average every 2-5 days) – basically each time one of the tagged sharks spends enough time on the surface for the tag to uplink to the ARGOS satellite network.
As previously reported back in November, the initial data received from June through October 2015 seemed to confirm what many suspected – that Cendrawasih whale sharks are largely “homebodies”, preferring to stay close to shore and feed upon the abundant ikan puri baitfish schools that abound in the coastal bays and estuarine areas of the southern and eastern coastlines of Cendrawasih. Which of course is a great thing for BHS marine tourism, as it means visitors can pretty much plan a trip any time of the year and have a very good chance of excellent whale shark interactions.
By December, however, we started to observe some very different behaviours that indicate Cendrawasih’s whale sharks might not be such homebodies after all! Just before Christmas, four of the sharks almost simultaneously moved towards the small exit to the bay between the eastern tip of Yapen Island and the Papuan mainland. Though two soon turned back, both “Jude” and “Wally” proceeded down the coastline towards Jayapura. Jude eventually turned back and returned to Kwatisore, but Wally continued down the coast – becoming the first of our tagged sharks to become an international visitor when he crossed into PNG waters in early January. While he appeared at one point to be returning to Cendrawasih (making it as far west as Jayapura), he’s since returned to the Wewak region of PNG (near the Sepik River outlet) and seems to be happily enjoying an extended vacation there!
Similarly, one of our most recently tagged whale sharks, Ke’Opulupulu, headed almost immediately north into the center of the Bay (near the Auri Islands and atolls), then navigated to the south coast of Biak and Supiori Islands, where he’s remained for the past few weeks.
But horizontal movements are only part of the excitement we’ve recently recorded. The past 3 months have also seen a dramatic increase in deep-diving behaviour of many of our tagged sharks. While we did previously report a 672m deep diving record in October, we’ve now seen four of our sharks venture below 1000m depth, with the aptly-named “Moby” smashing the depth record (but fortunately not his tag’s depth gauge!) at 1416m!!! Even the “wee” 3m “Fijubeca” has dived to 700m depth. It’s still not clear why the sharks have shown such deep diving behaviour over the past few months – perhaps the El-Nino warmed surface waters are not providing enough food and they are searching for deeper plankton…
Overall, we’re delighted to see these fin-mount tags proving so successful at divulging some of the secrets of Cendrawasih’s whale sharks. Its particularly noteworthy that the first 5 months’ of data seemed to simply confirm our scattered direct observations, but the past 4 months have revealed numerous exciting behaviours we didn’t expect. Who knows what the next few months’ data might reveal? Stay tuned and we’ll happily report back as the data keeps flowing in. And please remember – you too can contribute to our expanding knowledge and understanding of the charismatic megafauna of the Bird’s Head by contributing your photo IDs and observations of whale sharks and manta rays in the region to the databases maintained by our site.
Mark Erdmann is Conservation International’s Vice President of Asia Pacific Marine Programs. Though now based in New Zealand after 23 years in Indonesia, he is still intimately involved with the Bird’s Head Seascape and frequently disappears into its remote corners for weeks on end….
Shawn Heinrichs is an Emmy Award-winning cinematographer, photographer and marine conservationist. An independent filmmaker, he is the founder of Blue Sphere Media, a production company specializing in underwater, adventure and conservation media. His work was recently featured in the film Racing Extinction.
A special thanks to Audrey, Shannon and Dennis Wong, Sally Timpson, and the management and guests of the True North expedition vessel for generously sponsoring the fin-mount whale shark satellite tags reported here, to Patti Seery and her amazing staff and crew of the Si Datu Buah liveaboard for hosting our most recent deployment expedition, and to OceanMax for continuing to support the tagging program with PropSpeed silicone foul-release coating for our satellite tags.
Video Series: The CCMI Reef Lectures – Part 4 (Watch Video)
Introduced by Jeff Goodman
Never before since human beings have had major influence over our earths climate and environments, have we come to so close to the brink of global disaster for our seas and marine life. We need to act now if we are not going to crash headlong into irreversible scenarios.
A good start to this is understanding how the marine environment works and what it means to our own continued survival. We can only do this by listening and talking to those with the experience and knowledge to guide us in the right direction.
CCMI (Central Caribbean Marine Institute) are hosting an annual Reef Lecture series that is open to the general public and Scubaverse will be sharing those lectures over the coming months.
Part 4: Stop Whining! Life as an Ocean Ambassador; Ellen Cuylaerts
Ellen Cuylaerts shares her insights on how to act, practice what you preach and use your voice to contribute to constructive change. Ellen is a wildlife and underwater photographer and chooses to take images of subjects that are hard to encounter like harp seal pups, polar bears, orcas, beluga whales and sharks, to name a few. By telling the stories about their environment and the challenges they face, she raises awareness about the effect of climate change on arctic species, the cruel act of shark finning and keeping marine mammals in captivity.
During this seminar, Ellen will take you on a virtual trip and show you the stories behind the shots: how to get there, how to prepare, how to create the most chances to come home with a shot, and how to never give up!
Ellen Cuylaerts is an ocean advocate, underwater & wildlife photographer, explorer, and public speaker.
For more information about the CCMI click here.
Fit filters in washing machines and slow the tide of ocean plastic
The Marine Conservation Society’s Stop Ocean Threads campaign, which is calling for all new washing machines to be fitted with microfibre filters, by law, by 2024, aims to stop plastic pollution at source by filtering microscopic plastics from washing machine waste water.
To date the charity’s petition has been signed by over 12,000 people. The petition calls on government to introduce legislation which requires all new washing machines to be fitted with microfibre filters by law. Now, the charity is taking direct action and encouraging supporters to tweet washing machine manufacturers, putting pressure on them to fit filters on all new washing machines and slow the tide of microfibres entering the ocean.
Research conducted by YouGov on behalf of the Marine Conservation Society revealed that most (81%) adults surveyed supported legislative change and a quarter (26%) of those said that they would be willing to pay an additional £50 or more for a washing machine fitted with a microfibre filter. Not only is there is clear public support for legislation to Stop Ocean Threads, but consumers are willing to pay extra for their washing machines to have ocean-friendly credentials.
It’s increasingly important to put this issue top of the agenda for washing machine manufacturers who can take action now helping to address the microplastic issue, rather than waiting for legislation to be put in place.
Dr Laura Foster, Marine Conservation Society’s Head of Clean Seas says: “Our research has found that the public is largely supportive of our call for legislation, and consumers are willing to pay a little more to reduce the flow of microplastics into the ocean.
“It’s fantastic to see the support our petition has received so far, but now we need the public to show their support and join our action to engage with manufacturers directly. If we can show manufacturers that the public wants these filters fitted as soon as possible, we hope to speed up the legislative process and get filters fitted in the near future.”
Members of the public are encouraged by the Marine Conservation Society to go direct to washing machine manufacturers, and get involved in the charity’s tweet action.
“Hey @Miele_GB @BekoUK @Hoover_UK @BoschUK @SamsungUK @WhirlpoolCorp We want washing machine manufacturers to commit to fitting microfibre filters before 2024. Will you do this and help us #StopOceanThreads? Please retweet and share far and wide”
WIN a Bigblue AL-1200NP Dive Torch!!!
For this week’s competition, we’ve teamed up with our good friends at Liquid Sports to give away a Bigblue AL-1200NP Dive...
WIN a Tovatec T3500S Rechargeable Dive Light!!!
For this week’s competition, we’ve teamed up with our good friends at CPS Partnership to give away a Tovatec T3500S Rechargeable Dive Light...
WIN a Fourth Element Arctic Hoodie!!!
For this week’s competition, we’ve teamed up with our good friends at fourth element to give away one of their NEW Arctic...
WIN a Northern Diver NDB5 Holdall Bag!!!
For this week’s competition, we’ve teamed up with our good friends at Northern Diver to give away one of their NDB5 Holdall...
Sharks Bay Umbi Diving Village is a Bedouin-owned resort with stunning views and a lovely private beach. It is ideal for divers as everything is onsite including the resort's jetty, dive centre and house reef. The warm hospitality makes for a diving holiday like no other. There is an excellent seafood restaurent and beach bar onsite, and with the enormous diversity of the Sharm El Sheikh dive sites and the surrounding areas of the South Sinai, there really is something for every level of diver to enjoy.More Less
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