Sweetilps feeding at dusk
The rays had a full-moon party in the lagoon at high tide…
A sea cucumber’s view of the world
A lone bleached coral exposed during the full moon low tide
Seaweed from the halos, up close and personal
We’ve just returned from a week on Heron Island on the southern Great Barrier Reef. On this trip, we did some highly experimental work with night-vision type equipment to allow us to see what happens on the reef at night when no one is around. Specifically, we were interested to find out who’s making the grazing halos we’ve been studying there – beyond the players we’ve observed from our daytime remote videos. To do this we used a fleet of modified, infrared-sensitive GoPro cameras, as well as unmodified GoPros, and red lights mounted on a custom-made rig designed by Osmar Luiz. Despite some hiccups (i.e., flooded cameras) and some eerie lagoon snorkels at dusk (i.e., dinner time for some of the reef’s larger inhabitants!), the trip was a great success. A huge thanks goes out to the awesome team of field assistants, too: Vincent Raoult from Macquarie University, Veronica Radice from the University of Queensland, and Nathan Caromel from Griffith University. We also had the good fortune of working with Morad Ait-Habbouche, a veteran French filmmaker working on a climate change documentary.
We’re just starting to process the nighttime videos now and are excited to see what we find…
Due largely to the record-breaking high temperatures we’ve had lately, large sections of the northern Great Barrier Reef have begun bleaching (i.e., expelling the symbiotic algae that live within coral tissue and serve as a life-support system for corals). This is very bad news. In past bleaching events like this, some coral reefs never recover and become seaweed-dominated reefs lacking coral. Most experts agree that the root causes of the high temperatures (and the resulting coral bleaching events) include the burning of fossil fuels and release of other greenhouse gases into the atmosphere (e.g., through beef production)…which are both ultimately driven by human overpopulation and overconsumption.
Below are some recent photos taken by coral reef scientists Wen-Sung Chung and Justin Marshall (University of Queensland) from Lizard Island on Australia’s northern Great Barrier Reef. They tell a sad, rapidly-unfolding story of desperate corals.
While in Key West recently, we also had a chance to get a quick look at the grazing halos that are about 8 kms offshore within the Western Sambo Ecological Reserve. Years ago, Dr. Tom Adam pointed these out to me on Google Earth, and they’re still some of the clearest examples of grazing halos we’ve seen anywhere in the world. I’ve always been curious about what the patch reef communities within the halos look like. It turns out they’re quite beautiful, with lots of sea fans and sea whips and fairly high live coral cover (though no staghorn or elkhorn, at least at the ones we visited). There were also more predatory fish than I expected to see for a place as heavily fished as the Keys. The halo itself was as clear as you’d expect from the imagery, with essentially bare sand adjacent to the reef. This bare area extends for about 6-8 metres, at which point the seagrass becomes increasingly dense and tall – just as we’d expect from theory and the satellite imagery.
One of the reefs/halos we surveyed, as seen from satellite imagery
Lush seagrass outside of the bare grazing halos, far from the reef
Inside the grazing halo, near the reef
Osmar‘s just returned from a very windy, but successful, trip to Lizard Island on the far north Great Barrier Reef. He was there to help create extremely high-resolution 3D maps of the reef that was largely destroyed by category 4 Cyclone Nathan a few months ago. This work is part of a larger project led by Dr. Joshua Madin of Macquarie University and Sydney University’s Australian Centre for Field Robotics that uses robotic torpedoes help map our corals on Great Barrier Reef. Read more about it here.
The robotic torpedo used by the group to make maps of the reef on previous trips.
One of the composited 3D texture-mapped models of the reef.
I spent the past few days aboard the vessel Ocearch at beautiful Ningaloo Reef in remote Western Australia. The trip was cut short by – yet again – a cyclone! This time it was Cyclone Quang that hit bang onto Ningaloo just as I was set to arrive. I guess there’s never a dull moment when you work in the tropics.
The reef, however, looked amazing – extremely high coral cover and an apparent abundance of predators big and small. I didn’t see any evidence of cyclone destruction in the spot where we were.
The Ocearch crew + the science team caught and tagged 20 tiger sharks in just nine days. You can follow those (and other) sharks’ movements here (and, if you’re like me, keep an eye on how close they are to your favourite surf spots!).
The reef, with quite high coral cover. Being next to a desert has its advantages…Ningaloo is spared much of the land-based pollution that washes into it’s east coast analogue, the Great Barrier Reef.
A friendly turtle that joined our dive.
What you can and can’t do in the marine park.
The Ocearch vessel. Big and solid.
Sunrise over the desert and reef.
Some beautiful land forms adjacent to the reef.
Dr. Emily Darling of the Wildlife Conservation Society has written a new blog post on our recent trip to Heron Island! Follow Emily’s other amazing, globetrotting adventures on Twitter! @emilysdarling.
Our recent trip to Heron Island was a great success, despite a minor drone crash and some trying winds…the team was great and we had lots of fun in the process! One of the products arising from this work will be an open-source, best practices-type manual to serve as a toolkit to help other researchers, conservation practitioners and resource managers use drones to survey reefs and other marine environments. We also collected lots of samples to see how predators may indirectly affect blue carbon storage as part of the Global Change Institute grant. Stay tuned! (All photos are by Brian Sullivan unless otherwise noted.)
Team Halo: Emily Darling, Edd Hamill, Trisha Atwood, Quinn Olivier, Elizabeth Madin. Also part of the team but not shown: Brian Sullivan (the man behind the camera), Alastair Harbourne, Andy Goodwin.
Heron lagoon as seen from RV Boult. Photo: Elizabeth Madin
Edd Hammill and Trisha Atwood working hard…
One of the drones that Andy built to get aerial imagery of the lagoon reefs. Elizabeth Madin and Andy Goodwin.
Brian Sullivan recovers the drone after a flight… Photo: a selfie, perhaps?
The eagle ray kite we used to fly the camera post-drone crash. Photo: Emily Darling
Elizabeth learning how to take Underwater Street View imagery.
Grazing halos surrounding patch reefs in the lagoon of Heron Island, part of Australia’s Great Barrier Reef.
Elizabeth and colleagues Dr. Trisha Atwood (lead investigator; University of Queensland/University of Technology Sydney), Dr. Alastair Harbourne (University of Queensland) and Dr. Pete Macreadie (University of Technology Sydney/Deakin University) have just been awarded a seed grant from the University of Queensland’s Global Change Institute to study how predators may be indirectly affecting blue carbon storage in grazing halos. This group, along with collaborators from Google and ConservationDrones.org, will be heading to Heron Island in Nov. 2014 to start work on this project.
Pre-cyclone fun…Bob Warner and Elizabeth in between dives at one of the field sites in the lagoon at Lizard Island.
Bob Warner wrangling one of the model predators (thanks, Mark McCormick!!) before setting it off on the underwater pulley system to scare smaller fish.
Cycle Ita passed recently right over Lizard Island (far north Great Barrier Reef, Australia) where Elizabeth and colleagues Prof. Bob Warner (University of California, Santa Barbara), Dr. Isabel Downs, and Dr. Josh Madin (Macquarie University) were working on an Australian Research Council-funded collaborative project with Dr. Lexa Grutter (University of Queensland) to look at the effects of cleaner wrasses on changing predation risk for bystander species. Sadly, much of the island’s infrastructure was destroyed, however the Lizard Island Research Station fortuitously survived the cycle largely intact. Fortunately, we got a solid week and a half of work in before the evacuation…