Posts about fish

Using Scientific Knowledge to Drive Policies that Create a Better World

I have written about the problems of overfishing in the past: Add Over-Fishing to the Huge Government Debt as Examples of How We Are Consuming Beyond Our Means (2012)Fishless Future (2006)North American Fish Threatened (2008)The State of the Oceans is Not Good (2011)European Eels in Crisis After 95% Decline in Last 25 years (2009). This is not a complicated problem. If you just pay attention to the science and make wise decisions with an understanding of systems we can improve the situation.

And the USA has done so. The USA has more work to do, but by taking sensible steps based on an understanding of science we have made significant progress.

How the world can stop overfishing – A case study of U.S. fishery success

By 1996, the US had declared 86 species overfished. Fast forward twenty years, and only 29 species in US waters are classified as overfished. That’s a decrease of 66% from the peak of overfishing in the 1990s.

One year after President Clinton declared the New England ground fishery a federal disaster, congress met in Washington to amend and renew the 20-year-old Fishery Conservation and Management Act. The result was the Magnuson-Stevens Act, a major bipartisan commitment to end overfishing in US waters and promote fish stock recovery.

The goal of the Magnuson-Stevens Act was to create a framework for rebuilding overfished stocks in as short a time as possible. The timeframe for rebuilding a fish stock under the act is typically ten years or less.

To accomplish such a goal, scientists established fishery management plans for each overfished stock and instituted annual catch limits to control overfishing.

By the end of 2015, 89% of fisheries with annual catch limits in place had halted overfishing.

While 64% of the fish stocks managed by the Magnuson-Stevens Act are now rebuilt or recovering, success hasn’t been universal. Certain regional fisheries, such as those in the Gulf of Mexico and New England, have struggled to control overfishing under existing regulations. The act also does a poor job of protecting highly migratory species, such as tuna, swordfish, and sharks, which move freely between different regulatory areas.

We need to build on our successful use of scientific knowledge to make wise decisions and implement wise government policy. Sadly there is an alarming lack of appropriate thinking by many of those we elect to office, in the USA and around the globe. We can’t afford to elect people that don’t have an understanding of how to make wise decisions and how to ensure scientific knowledge forms the basis of policy when it should, such as: overfishing, pollution, global warming, the health care benefits vaccines provide when they are used properly, the dangers of abusing antibiotics, etc..

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How Healthy Is Squid for Us?

I try to eat healthfully, especially when I can tweak what I eat to gain a health advantage. I know fish have good qualities. I live in Malaysia now and squid (called sotong here) is often available. I often prefer squid to fish here as the fish use here are often fairly small with bones to deal and not much meat for the effort (it is great sometimes but I am often lazy).

photo of squid dinner

Sambal Sotong (squid) with bitter gourd (home delivery). Very tasty. The bitter gourd is very bitter, but a few bites are ok.

So I looked online for some details, it wasn’t as easy I would have hoped. The Shellfish Association of Great Britain offered a good overview.

They say 100g of raw squid (pre cooking weight) provides about 200% of Vitamin B12, 100% of Selenium, 80% of Copper, 50% of Vitamin B6, 35% of Vitamin E, 34% of Phosphorous, 30 % of Protein, 20% of Niacin, 10% of B1 (Thiamin), 8% of Potassium, 10% of Magnesium, 14% of Zinc.

From various sources online it seems there are 92 calories in 100 grams of Squid with a calorie breakdown of 72% protein, 14% fat and 14% carbs.

From the Heart Association of Australia “omega-3s are found primarily in oily fish, such as Atlantic and Australian salmon, blue-eye trevalla, blue mackerel, gem fish… Other fish such as barramundi, bream or flathead, and seafood such as arrow squid, scallops and mussels, are also good sources of omega-3… To reduce the risk of heart disease, the Heart Foundation recommends that Australian adults consume about 500 milligrams of omega-3 (marine source) every day.”

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Deadly Trio of Acidification, Warming and Deoxygenation Threaten Our Oceans

An international panel of marine scientists is demanding urgent remedies to halt ocean degradation based on findings that the rate, speed and impacts of change in the global ocean are greater, faster and more imminent
than previously thought.

Professor Dan Laffoley, International Union for Conservation of Nature, said: “What these latest reports make absolutely clear is that deferring action will increase costs in the future and lead to even greater, perhaps irreversible, losses. The UN climate report confirmed that the ocean is bearing the brunt of human-induced changes to our planet. These findings give us more cause for alarm – but also a roadmap for action. We must use it.“

Results from the latest International Programme on the State of the Ocean (IPSO)/IUCN review of science on anthropogenic stressors on the ocean go beyond the conclusion reached last week by the UN climate change panel the IPCC that the ocean is absorbing much of the warming and unprecedented levels of carbon dioxide and warn that the cumulative impact of this with other ocean stressors is far graver than previous estimates.

Decreasing oxygen levels in the ocean caused by climate change and nitrogen runoff, combined with other chemical pollution and rampant overfishing are undermining the ability of the ocean to withstand these so-called ‘carbon perturbations’, meaning its role as Earth’s ‘buffer’ is seriously compromised.

Professor Alex Rogers of Somerville College, Oxford, and Scientific Director of IPSO said: “The health of the ocean is spiraling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth.”

Among the latest assessments of factors affecting ocean health, the panel identified the following areas as of greatest cause for concern:
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Add Over-Fishing to the Huge Government Debt as Examples of How We Are Consuming Beyond Our Means

Fish are hidden under the water so the unsustainable harvesting isn’t quite as obvious as the unsustainable government debt but they both are a result of us living beyond our sustainable production. You can live well by consuming past wealth and condemning your decedents to do without. That is the way we continue to live. Over-fishing a century ago was not as obviously dangerous as it is today. But we have witnessed many instances of overfishing devastating the fishing economy (when the fishing is unsustainable the inevitable result is collapse and elimination of the vast majority of the food and income that previous generations enjoyed).

The normal pattern has been to turn to more aggressive fishing methods and new technology to try and collect fish as over-fishing devastates yields. This, of course, further devastates the state of the resources and makes it so recovery will take much much longer (decades – or more).

New research shows the existing problems and the potential if we apply science and planning to manage fisheries effectively.

Using new methods to estimate thousands of unassessed fisheries, a new comprehensive study provides a new view of global fish stocks. The results show that the overall state of fisheries is worse than previously thought. Unassessed stocks, which are often left out of global analyses because of a lack of data, are declining at disturbing rates. When these fisheries are taken into account, the results indicate that over 40 percent of fisheries have crashed or are overfished, producing economic losses in excess of $50 billion per year.

The good news is that this decline is not universal: fisheries are starting to rebound in many areas across the globe and we can learn from these examples. Recovery trends are strongest for fisheries where data on the status of the fishery exists, and in which managers and fishermen have made science-based decisions and stuck with them in the face of political pressure.

The amount of fish brought to shore could increase 40 percent on average – and double in some areas – compared to yields predicted if we continue current fishing trends.

The management solutions to overfishing are well known, tested and proven to work. While these solutions are not “one-size-fits-all” for fisheries, there are common themes. Specifically, managers and fishermen must: 1. Reduce fishing to allow stocks to rebuild; 2. Set catches at a sustainable level that is based on the best available scientific and economic information rather than short-term political pressures; and 3. Prevent dangerous fishing activities that destroy habitat, wildlife, or breeding fish.

The over fishing problem is difficult because our nature is to ignore problems that are not immediate. But the costs of doing so are very large. If we don’t behave more wisely our children will pay the price. And, in fact, this problem is so acute now that those of us that expect to live a couple decades can expect to pay the price. In rich countries this will be tolerable, a bit less fish at much higher prices. In rich countries food prices are a minor expense compared to the billions of those not living in rich countries. They will suffer the most. As will those that have jobs directly dependent on fishing.

Related: Fishless FutureEuropean Eels in Crisis After 95% Decline in Last 25 yearsLet the Good Times Roll (using Credit)SelFISHingRunning Out of FishThe State of the Oceans is Not GoodChinook Salmon Vanish Without a Trace

Bird Using Bread as Bait to Catch Fish

Very clever technique. Quite an effective strategy to take a byproduct of people (bread) and use it to lure in your prey. I posted another bird fishing using bait webcast previously: that post includes links to more such videos.

Related: Orangutan Attempts to Hunt Fish with SpearDolphins Using Tools to HuntIntelligent Dolphin Strategy for Hunting Fish

The Secret Life of Plankton

Fun video with great shots of exotic ocean life that forms the base of the food chain in the ocean from TED Education.

Related: Hydromedusae, Siphonophora, Cnidarians, CtenophoresMilestones on the Voyage to the Bottom of the SeaMacropinna Microstoma: Fish with a Transparent Head

Photo of Fish Using a Rock to Open a Clam

photo of a blackspot tuskfish using a rock to crack open a clam

Blackspot tuskfish using a rock to crack open a clam. Photo by Scott Gardner

Diver Snaps First Photo of Fish Using Tools

While exploring Australia’s Great Barrier Reef, professional diver Scott Gardner heard an odd cracking sound and swam over to investigate. What he found was a footlong blackspot tuskfish (Choerodon schoenleinii) holding a clam in its mouth and whacking it against a rock. Soon the shell gave way, and the fish gobbled up the bivalve, spat out the shell fragments, and swam off. Fortunately, Gardner had a camera handy and snapped what seem to be the first photographs of a wild fish using a tool.

Tool use, once thought to be the distinctive hallmark of human intelligence, has been identified in a wide variety of animals in recent decades…

There have also been a handful of reports of fish cracking open hard-shelled prey, such as bivalves and sea urchins, by banging them on rocks or coral, but there’s no photo or video evidence to back it up, according to Culum Brown, a behavioral ecologist at Macquarie University in Sydney, Australia, and a co-author of the present paper, to be published in a forthcoming issue of Coral Reefs.

The more we learn about animals the more tool use we find. It is continually interesting to see the wide variety of behavior documented.

Related: Bird Using Bait to FishDolphins Using Tools to HuntOrangutan Attempts to Fish with SpearAncient Chimps Used Stone “Hammers”

The State of the Oceans

World’s oceans in ‘shocking’ decline

In a new report, [an expert panel of scientists] warn that ocean life is “at high risk of entering a phase of extinction of marine species unprecedented in human history”. They conclude that issues such as over-fishing, pollution and climate change are acting together in ways that have not previously been recognised.

ocean acidification, warming, local pollution and overfishing are acting together to increase the threat to coral reefs – so much so that three-quarters of the world’s reefs are at risk of severe decline.

The report also notes that previous mass extinction events have been associated with trends being observed now – disturbances of the carbon cycle, and acidification and hypoxia (depletion of oxygen) of seawater.

Levels of CO2 being absorbed by the oceans are already far greater than during the great extinction of marine species 55 million years ago (during the Paleocene-Eocene Thermal Maximum), it concludes.

The overfishing of our oceans has been a problem for over 100 years and a known problem, that we continue to give too little attention to. Adding to that impacts of climate change and the state of ocean life is in trouble. The decision of our population to not deal with the causes of climate change will have very bad consequences. It is a shame we have so little caring about the consequences of our decisions. And even sadder that our “leaders” do such an appalling job of leading – instead they pander to selfish immediate gratification.

Related: Altered Oceans: the Crisis at Sea (2006)Unless We Take Decisive Action, Climate Change Will Ravage Our PlanetArctic System on Trajectory to New, Seasonally Ice-Free State (2005)

Surprise Shrimp Under Antarctic Ice

A three-inch long Lyssianasid amphipod found 600 feet beneath the Ross Ice Shelf stars in a recent popular webcast (see below). NASA scientists were using a borehole camera to look back up towards the ice surface when they spotted this pinkish-orange creature swimming beneath the ice.

Stacy Kim of Moss Landing Marine Laboratory was the first biologist to see the video and immediately recognized it as a Lyssianasid amphipod. It was about 3 inches long and Stacy concluded that this meant there was quite an extensive biological community under the ice here – even 20 miles from open water.

Related: Iron-breathing Species Isolated in Antarctic for Millions of YearsPine Island Glacier (PIG) Ice ShelfThe Brine Lake Beneath the SeaLake Under 2 Miles of Ice
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Unique Dolphin Strategy for Hunting Fish

A pod of bottle-nose dolphins off the coast of Florida have developed a hunting technique unknown in other dolphins. One swims in a circle stirring up mud and then the dolphins wait to catch fish that jump out of the water to escape the contracting circle of muddy water.

Related: Dolphins Using Tools to HuntDo Dolphins Sleep?Dolphin Delivers Deviously for RewardsBird Using Bait to FishDolphin Rescues Beached Whales

Sustainable Aquaculture

Sustainable Aquaculture

Located on an island in the Guadalquivir river, 10 miles (16km) inland from the Atlantic, Veta la Palma produces 1,200 tons of sea bass, bream, red mullet and shrimp each year. Yet unlike most of the world’s fish farms, it does so not by interfering with nature, but by improving upon it. “Veta la Palma raises fish sustainably and promotes the conservation of birdlife at the same time,” says Daniel Lee, best practices director for the U.S.-based Global Aquaculture Alliance. “I’ve never seen anything quite like it.”

With wild fish stocks declining precipitously around the globe, thanks to overfishing and climate change, aquaculture has emerged as perhaps the only viable way to satisfy the world’s appetite for fish fingers and maki rolls. In the next few years, consumption of farm-raised fish will surpass that caught in the wild for the first time, according to the United Nations Food and Agriculture Organization. But most fish farms — even ones heralded as “sustainable” — create as many problems as they solve, from fecal contamination to the threat that escaped cultivated fish pose to the gene pool of their wild cousins.

Veta la Palama is different. In 1982, the family that owns the Spanish food conglomerate Hisaparroz bought wetlands that had been drained for cattle-farming and reflooded them. “They used the same channels built originally to empty water into the Atlantic,” explains Medialdea. “Just reversed the flow.” Today, that neat little feat of engineering allows the tides to sweep in estuary water, which a pumping station distributes throughout the farm’s 45 ponds. Because it comes directly from the ocean, that water teems with microalgae and tiny translucent shrimp, which provide natural food for the fish that Veta la Palma raises.

By hewing as closely as possible to nature, the farm avoids many of the problems that that plague other aquaculture projects. Low density — roughly 9 lb. (4 kg) of fish to every 35 cu. ft. (1 cu m) of water — helps keep the fish free of parasites (the farm loses only 0.5% of its annual yield to them). And the abundant plant life circling each pond acts as a filter, cleansing the water of nitrogen and phosphates.

Related: Rethinking the Food Production SystemFishless FutureEat food. Not too much. Mostly plants.Running Out of Fish