State of the Oceans — Log 69
YOUR WEEKLY BRIEFING FROM PARLEY
This image by Gaetano Cessati, header image by Tyler Lastovich
CLIMATE CHANGE
We already know the oceans are warming, acidifying and losing oxygen – now research indicates that ocean currents are getting faster, too. According to a groundbreaking study in Science Advances, global ocean circulation has been picking up speed since the 1990s.
Scientists detected this trend by examining decades of data from kinetic energy (e.g. movement) sensors placed all over the world. The researchers believe that climate change is causing wind patterns to accelerate, which in turn gives ocean currents more momentum.
The consequences remain largely unknown, but it’s possible that accelerated seas will change the planetary distribution of heat and nutrients and even increase the rate of glacial melting. “It is expected that the acceleration of global mean ocean circulation has wider implications,” the study’s lead author said, “but further studies are needed.”
ILLEGAL FISHING
All over the world “dark ships” turn off their public tracking systems to fish illegally, avoid sanctions, and maybe even run from oil spills. To combat this threat, researchers have recruited a surprising ally: albatrosses. As part of a six-month pilot study, scientists strapped GPS trackers to 169 albatrosses all across the Indian Ocean. In that time, the seabirds – which often follow fishing vessels to find food – covered 47 million square miles and detected over a hundred ships with public signals switched off in international waters. “There is wonderful elegance in using birds to monitor fishing vessels, largely because these vessels threaten some bird populations,” said one researcher not involved in the study. “It is great to see teamwork with nature.”
SUSHI
From Norway to Japan, increasing sea urchin populations are devouring kelp forests, which are key habitat for marine life and also carbon sinks. After grazing, sea urchins – “uni” in Japanese – can hibernate until new kelp has sprouted, eat again, and prevent the forest from ever recovering. To combat this, a company called Urchinomics hopes to collect urchins and sell them to high-end sushi restaurants. Kelp have shown a remarkable ability to rebound after urchins are removed, and the demand for uni is already rising. “The more you eat the urchins, the better it is for the kelp forests,” said the company’s CEO. “It has to be about looking towards these win-win situations where you’re creating some sort of economic incentive to help drive the restoration work.”
MARINE LIFE
For twenty years, whale and dolphin sightings have decreased in the Phillipines’ Tañon Strait, a migratory route for at least eleven cetaceans species and also one of the country’s busiest sea lanes. According to a recent survey, boat traffic and other human activities may be responsible for the downward trend. Some good news: the surveyors spotted rose-bellied dwarf spinner dolphins in the Strait, which was just the second time the species has been seen in the Philippines. The survey’s leader said, “The main challenge for managers of any protected area is always how to balance protection of a species or their natural habitat with the needs and demands of the community living around it.”
SHIPPING LANES
The world’s largest fish may face an increased risk of ship strikes. In Ningaloo Marine Park in Australia, scientists analyzed photographs of over 913 whale sharks taken between 2008 and 2013. One fifth of all the images showed scarring and amputations consistent with injuries from boating accidents, and the photos from 2012 and 2013 implied that the collision rate had doubled since 2011. Of course, this study does not capture the whole story because victims of a fatal collision sink to the ocean floor and are not photographed. Between 1992 and 2012, global shipping traffic rose fourfold, and in the words of one researcher, “It looks like this threat has been increasing.”
Share your thoughts and join the conversation on social media
IG @parley.tv | TW @parleyforoceans | FB @parleyfortheoceans
#StateOfTheOceans