September 5, 2018 — Thanks to Global Fishing Watch, a new partnership between Oceana, SkyAtlas, and Google, scientists may be getting closer to figuring out how much of the world’s ocean is fished—but discrepancies in the scale of data are producing wildly different answers.
Need To Track A Submarine? A Harbor Seal Can Show You How
September 4, 2018 — Using lessons learned from harbor seals and artificial intelligence, engineers in California may be on to a new way to track enemy submarines.
The idea started with research published in 2001 on the seals.
Scientists at the University of Bonn in Germany showed that blindfolded seals could still track a robotic fish. The researchers concluded that the seals did this by detecting the strength and direction of the whirling vortex the robot created as it swam through the water.
Subsequent research showed that the seal used its whiskers as sensors to detect the flow patterns.
Eva Kanso, a professor of aerospace and mechanical engineering at the University of Southern California, is interested in how animals use water flows to guide their behavior. It’s an academic puzzle for Kanso, but a very real, very practical question for a harbor seal.
“The animal wants to understand — is it a prey that created this vortex, or is it a predator that created this flow pattern?” she says.
Kanso and her colleagues have been trying to emulate the seals’ ability to make those distinctions.
Melting ice poses fleeting ecological advantage but sustained global threat, Stanford scientist says
August 31, 2018 — From collecting field samples inside the ocean’s frozen ice pack to analyzing satellite images in the comfort of his Stanford office, Kevin Arrigo has been trying to figure out how the world’s rapidly thinning ice impacts polar food chains. Arrigo, a professor of Earth system science at Stanford School of Earth, Energy & Environmental Sciences, found that while melting ice threatens to amplify environmental issues globally, ice sheet retreat can provide much-needed food in local ecosystems.
Through this work, Arrigo discovered that thinning ice at the poles can alleviate polar food deserts by extending phytoplankton blooms. However, the silver lining associated with melting ice cannot make up for imminent threats, such as rising sea levels, associated with unchecked glacial shrinkage.
Arrigo, who is also the Donald and Donald M. Steel Professor in Earth Sciences, spoke with Stanford Report about his work on polar phytoplankton blooms and discussed whether recent news about sea ice breaking up suggests we’ve reached a tipping point.
What have you learned about how glacial melt impacts food chains in the extreme environments of the poles?
It turns out that when glaciers form, they accumulate particles and dust that contain essential nutrients like iron, on which all living things depend for survival. As glaciers melt, they add nutrients to the ocean and fertilize the local ecosystem. In Greenland and Antarctica, the ocean is short on iron, so melting glaciers make up for the lack of iron.
Read the full story at Stanford News
Global fisheries could still become more profitable despite global warming
August 30, 2018 — Researchers from Japan’s Hokkaido University, the University of California, Santa Barbara (UCSB), National Center for Ecological Analysis and Synthesis, and Environmental Defense Fund (EDF) found that harvesting sustainable amounts of seafood globally over the next 75 years can lead to higher total food production and profits, even taking into consideration the fish populations which are projected to decline as the ocean warms and habitats change.
This is because, under what has been determined as the best management scenario, some major fish and shellfish stocks that are commercially harvested, broadly referred to as fisheries, will grow and become more profitable, offsetting the many others projected to shrink or even disappear. On a global average, profitability could rise by 14 billion USD and harvest by 217 million metric tons above today’s levels, according to the study.
There is a catch. In the model, the growth was achieved under the projected moderate warming of 2.2°C (3.9°F) above average global temperatures by 2100. But if temperatures rise further, global fish harvest and profits are expected to decline below today’s levels even with the best management in place.
The researchers say their study, published in Science Advances, conveys an important message: the oceans can continue to be a source of healthy seafood and sustainable livelihoods for billions of people, but only if action is taken to manage the stocks well and limit the carbon emissions that drive climate change.
Fish populations could rise in warming climate with better management
August 30, 2018 — Better management of fisheries and fishing rights around the world could increase profits and leave more fish in the sea as long as measures to meet climate obligations are taken, new research has found.
Even if temperatures rise by as much as 4C above pre-industrial levels – in the upper range of current forecasts – the damaging effects on fishing can be reduced through improving how stocks are fished and managed.
Governments are meeting from 4 September in New York for the first round of talks on a new global treaty of the high seas, which would aim to conserve overfished stocks and make access to key fisheries more equitable. Any agreement is likely to take several years to negotiateand longer to come into force, but scientists say there is no time to be lost, given the magnitude of the threat to the world’s marine ecosystems.
Climate change is already causing the movement of some species as their traditional habitats grow warmer, and overfishing is wreaking heavy damage on stocks. However, by adapting fisheries management to a warming climate, and instituting better systems such as monitoring of fleets, the global catch can be increased despite these factors, according to the paper published on Wednesday in the journal Science Advances.
“This is a positive message amid the doom and gloom,” said Kristin Kleisner, one of the authors of the study and a senior scientist at the US Environmental Defense Fund. “We can control how we manage our fisheries. We will have severe effects [from climate change] but this shows what we can do as humans to control that.”
How Whale Poop Could Counter Calls to Resume Commercial Hunting
August 29, 2018 — Before whales dive into the darkness of the deep ocean they often come to the surface and release a huge plume of fecal matter—which can be the color of over-steeped green tea or a bright orange sunset. When Joe Roman, a conservation biologist at the University of Vermont, saw one of these spectacular dumps in the mid-1990s, he got to wondering: “Is it ecologically important? Or is it a fart in a hurricane?”
Roman and other researchers have since shown whale excrement provides key nutrients that fuel the marine food chain, and that it also contributes to the ocean carbon cycle. These important roles are now influencing scientific and economic arguments for protecting whales, at a time when calls for a resumption of whaling are growing. “The scientific community is coming to understand a new value of whales: their role in maintaining healthy and productive oceans,” says Sue Fisher, a marine wildlife consultant at the nonprofit Animal Welfare Institute. “We are beginning to see governments use this rationale to justify measures to protect whales.” But as the International Whaling Commission (IWC) prepares for its biennial meeting next month, the ecological services whales provide are set to split the gathered countries—with an unknown outcome for the whales.
Whale poop’s importance is nothing to sniff at. In a 2010 study Roman’s team found whale defecation brings 23,000 metric tons of nitrogen to the surface each year in the Gulf of Maine—more than all the rivers that empty into the gulf combined. This nitrogen fertilizes the sea by sustaining microscopic plants that feed animal plankton, which in turn feeds fish and other animals including the whales themselves. Studies have found similar effects elsewhere, and with other nutrients found in whale feces. And when they migrate, whales also redistribute nutrients around the globe. By moving them from higher latitudes, Roman says, the giant mammals could be increasing productivity in some tropical waters by 15 percent.
By stimulating the growth of microscopic plants called phytoplankton, whale scat may also help limit climate change. These tiny aquatic plants remove carbon from the atmosphere and carry it deep into the ocean when they die. Research in the Southern Ocean showed the iron defecated each year by some 12,000 resident sperm whales feeds phytoplankton that store 240,000 more metric tons of carbon in the deep ocean than the whales exhale. This means that, on balance, whales help lock carbon away.
Read the full story at the Scientific American
New Study Seeks To Reveal The Secrets Of Halibut
August 29, 2018 — Fred Bennett has been a fisherman for about 60 years and he just stared, perplexed, at a graph supposedly showing a halibut, tagged to track its progress, moving in the water column.
He shook his head in consternation and looked at fellow captain Mike Anderson who has spent more than 40 years on the water.
How is that possible? Bennett wondered.
Anderson was laughing.
It’s not, he said – unless the storied flat fish had been eaten by something, most likely a great white shark.
“The tag was hanging out near the bottom during the day and was near the surface of the water during the night time, plus the tag temperature shot up suddenly and stayed there – pretty clear indications that it was eaten by a shark,” agreed George Maynard, research coordinator at the Cape Cod Commercial Fishermen’s Alliance.
Stumping Bennett and Anderson would be tough. The two spent many years catching halibut, a great-tasting fish that is making fishermen money in Canada, and used to make fishermen money here. But stocks crashed, and for the last 18 years local fishermen have been allowed to land only one fish per trip, and that one has to measure at least 41 inches.
Read the full story at The Cape Cod Chronicle
Lobstermen Asked to Look Out for Tagged Crustaceans
August 29, 2018 — New England’s lobster fishermen are being asked to keep an eye out for tagged lobsters that are part of a survey of the valuable crustaceans.
The lobsters are tagged with green bars that say “SNECVTS” and black acoustic tags. They are part of a tagging program that’s part of a southern New England lobster study being conducted from May to November by Commercial Fisheries Research Foundation and the University of Rhode Island.
The study is designed to find out about lobster and Jonah crab abundance and distribution in the RI/MA Wind Energy Area, which is located south of Rhode Island and Massachusetts, in the area of Cox’s Ledge.
The Contributions of High-Seas Fisheries to Food Security
August 28, 2018 — The recent research article by Schiller et al. in Science Advances is a novel and useful summary of the key features of fisheries on the high seas – the species captured, the quantities of each targeted species caught, the countries doing most of the fishing, and the destinations of the various products. However, the main conclusion of the article – that high seas fisheries play a negligible role in addressing global food security – needs to be considered with some caution. Context is important – it depends on which countries on the globe we are talking about.
The reason for caution is that one third of the high-seas catch is sold as canned tuna. All skipjack tuna caught from areas beyond national jurisdiction (22.3% of the high-seas catch) is processed in this way, and 70% (9.2% of the catch) of yellowfin tuna caught on the high seas is also likely to be canned (based on the proportion of yellowfin tuna caught by purse-seining in world’s largest tuna fishery). Although much of this low-cost, nutritious food is processed in Asia and destined for Europe and the USA, canned tuna is also commonly found on the shelves of local stores in many developing nations.
Food-insecure Pacific Island countries are a case in point. In these nations, canned tuna provides dietary animal protein when sea conditions are too rough for nearshore fishing or when nearshore fish catches are seasonally low. Canned tuna comprises up to 15% of recommended fish consumption across this region and, even in those Pacific Island countries that process their own tuna, 10-60% of canned tuna is imported. Given that one third of global skipjack and yellowfin tuna catches are taken in areas beyond national jurisdiction, it is reasonable to assume that the canned products derived from these catches help underpin food security in Pacific Island countries with limited access to other sources of animal protein.
As the authors of the study mention, it is also important to consider that present-day patterns of high-seas fish catches are not necessarily a good guide to the future. The latest modelling (see chapter 14) of the expected responses of skipjack and yellowfin tuna in the Pacific Ocean to climate change indicates that greater proportions of the catch are very likely to be made on the high seas in the decades to come. All canned tuna markets are therefore expected to depend more heavily on skipjack and yellowfin tuna caught from the high seas in the years ahead.
Aquarium wins grant to test ropeless fishing gear
August 27, 2018 — The New England Aquarium has been awarded a $227,000 grant to test a ropeless fishing prototype to eliminate large whale entanglements in pot fishing gear, National Oceanic and Atmospheric Administration Fisheries announced.
The federal agency awarded more than $2.3 million to 14 groups to support bycatch reduction research projects. Bycatch includes fish, marine mammals and turtles in this program, which intends to work side-by-side with fishermen on their boats to develop solutions to some of the top bycatch challenges in the country, the agency said in its announcement.
“U.S. pot fisheries that target crustaceans are popular in New England, and are important economically and culturally,” according to the aquarium’s description of its project. “However, the critically endangered North Atlantic right whale, and other large species of whale and protected species can become entangled in the ropes used in pot fisheries.”
“Ropeless fishing” involves securing ropes to the seafloor where traps are being fished, and when the trap is ready to be hauled to check for catch, ropes are released to the surface by an acoustically triggered device, according to the aquarium.
In mid-July, the International Fund for Animal Welfare also funded a $30,000 test with Sandwich lobsterman David Casoni of one type of ropeless technology — an acoustic release system by Desert Star Systems — in cooperation with the Massachusetts Lobstermen’s Association.
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