Hakai

This Scientist Is Making Batteries Out of Recycled Crab Shells

Shellfish chitin is a starting material ripe for chemical modification.

If you want to work in Mark MacLachlan’s lab, it helps to have a taste for seafood. The chemist, who works at the University of British Columbia in Vancouver, is working on turning the discarded shells of shrimp, crabs, and lobsters into advanced materials that could be used in batteries, plastics, or even for growing new organs. And it is up to his students to provide a steady supply of carcasses.

“One of my students buys lobsters and crabs, eats them, and then brings the shells to work,” MacLachlan says. Another has managed to secure a free supply of shells from a seafood restaurant.

MacLachlan is after one particular component of the material that makes up the shells—chitin, a tough substance that is structurally similar to the cellulose in plant cell walls. Read more in Hakai.

Clawing Their Way to Victory

Research suggests fiddler crabs with regenerated claws have distinct fighting strategies.

Male fiddler crabs have one oversized claw, which they use to both attract females and to fight other males for the best breeding burrows on the beach. These fights can get violent, and crabs will sometimes lose their big fighting claw in the process. Fiddler crabs have the ability to regrow their claw, though the new one will never be as sturdy as the original, says Daisuke Muramatsu, a biologist at Kyoto University in Japan.

Even in their weakened state, the crabs must fight. Yet based on his new research, Muramatsu argues that fiddler crabs are more strategic fighters than we’ve given them credit for: he says they pick battles that account for their handicap, and use a strategy of bluff and counter-bluff to end disputes before they begin. Read more in Hakai.

No, Britain Isn’t Naming a Ship RRS Boaty McBoatface

The British people have spoken, and they really want to name their new, US $290 million polar research ship the RRS Boaty McBoatface.

In what probably seemed like a nice piece of public outreach, the United Kingdom’s Natural Environment Research Council (NERC) invited the public to suggest names for its new vessel, which is scheduled to sail in 2019. The funding council asked for names that were “inspirational and about environmental and polar science,” suggesting things like Endeavour, Shackleton, and Falcon.

But you can’t trust the Internet. Read more in Hakai.

The Ghosts of Fishers Past

Photo by Brian Owens

Photo by Brian Owens

Lost fishing gear keeps on doing the job it was designed for long after its owners are gone.

Lacuna is like most other humpback whales in the Atlantic Ocean. He overwinters in warm Caribbean waters—where humpbacks breed and give birth—and heads north in spring, toward colder waters to feast on the abundance of krill, copepods, and other tiny marine life.

For nearly two decades, Lacuna, recognizable by the unique pattern of black and white marks on the underside of his tail fluke, has beaten the same watery path from the southern Atlantic to the Bay of Fundy in eastern Canada without incident, managing to avoid the dangers an animal his size might encounter. But last July when whale watchers spotted him in the bay, he was entangled in ropes—he had run afoul of fishing gear.

Although it was impossible to tell the origin of the gear Lacuna was hauling around, the whale’s plight highlighted a growing threat worldwide, abandoned or lost fishing gear that endangers marine life—ghost gear. Ghost gear does the job it was designed for: to catch marine animals. The problem is that it continues to catch fish, turtles, birds, and whales, for as long as the gear exists. Even worse, as animals die in lost traps or nets, they act as bait to attract other marine life and the cycle continues for years or even centuries.

Around 640,000 tonnes of fishing gear is lost or abandoned worldwide each year, accounting for around 10 percent of all marine litter. Ghost gear entangles and kills an estimated 136,000 whales, seals, and other marine mammals annually, and likely millions more animals with lower profiles: fish, crustaceans, turtles, and birds. Read more in Hakai.

When Good Fish Die Young

Rising temperatures are suppressing survival rates for young fish.

Climate change is making fish die young. Over the past six decades, the proportion of fish that survive to adulthood has been going down, by three percent per decade on average, according to a new analysis of global fish stock data.

Compiling statistics on changing fish stocks for 127 species of fish in 39 different marine regions, ecology doctoral student candidate Greg Britten calculated that the bulk of the increase in fish juvenile mortality can be attributed to rising ocean temperatures and the declining abundance of phytoplankton. Read more in Hakai.

A Fishy Plan

Canada’s new government says it’s going to expand the country’s marine protected areas. Scientists worry the government is cutting corners to hit its goal.

Canada has a long way to go in protecting its oceans. The United Nations Convention on Biological Diversity wants 10 percent of the world’s marine and coastal environments protected by 2020. So far, Canada has set aside just 1.3 percent.

With Canada’s change in federal government this past October, meeting the UN’s marine protection target has leapt to the top of the priority list for Hunter Tootoo, Canada’s new minister of fisheries and oceans. In his mandate letter for the new minister, Prime Minister Trudeau listed—as his very first line item—the goal of protecting five percent of Canada’s coastal waters by 2017, and the full ten percent by 2020.

That’s good news, says Rodolphe Devillers, a marine geographer at Memorial University in St. John’s, Newfoundland. But he says that, in their enthusiasm, the government seems to be looking to cut corners. Read more in Hakai.

The Living Lice Comb

IMG_7281Aquaculture adopts integrated pest management techniques for water-borne pests.

Like their land-based colleagues, fish farmers have to deal with pests and parasites that attack their animals. And like famers on land, they are looking for natural ways to deal with the pests that minimize the use of chemical treatments.

For salmon farms on the east coast of Canada, that means finding a way to fight the sea lice that can plague their open-water net pens. The aquaculture industry is now experimenting with using “cleaner fish,” such as cunner fish and lumpfish, to help control lice numbers, similar to how land-based integrated pest management techniques use natural predators to control pests. Read more in Hakai.

Oil Sands Dilbit Causes Developmental Problems in Fish

Scientists have very little idea what the environmental effects of an oil sands “dilbit” spill would be.

The oil that flows in pipes away from Canada’s oil sands is not the same as conventional crude oil. Known as diluted bitumen, or “dilbit,” this proprietary blend of oil and chemicals behaves differently in the event of a spill. Or, scientists suspect it does. So little research has been done on the environmental and ecological effects of dilbit that it’s hard to say for sure. As a first step toward understanding the risks posed by dilbit, scientists working with Alberta oil sands dilbit found that the tacky mixture can cause a range of serious toxic effects in fishRead more in Hakai.

Blood in the water

Proteins from salmon blood can stop bleeding and alleviate pain.

In pens and hatcheries along the coasts of New Brunswick, Canada, and Maine, USA, young salmon are growing into adults that will soon grace dinner plates around the world. But these fish have much more to offer than just their delicious pink meat. If on-going research pans out, medicines derived from salmon blood could help save human lives and, possibly, mitigate chronic pain. Read more in Hakai.

Repelling a Hunter

Scientists are still not really sure if, or how, magnetic shark repellents work.

Sharks get a bad rap, though sometimes for good reason. At times they can be a nuisance, or even a threat. They eat endangered seals; occasionally take a bite out of unsuspecting swimmers and surfers; and, to their own detriment, get caught in gear intended for other fish. Technology that would allow people to repel hungry sharks might save countless lives—particularly the sharks’. Read more in Hakai.