Salmon Sea Lice Infestation Leads to Price Spike


An outbreak of sea lice in Norway, the world’s largest source of farmed salmon, has fish farmers scrambling to find solutions and has caused a dramatic increase in the price of salmon. And pretty soon, we will all be paying more for our favorite Omega-3 fatty fish at the supermarket.

Salmon louse. Credit: Thomas Bjørkan/Wikimedia Commons, CC BY-SA 3.0

The sea lice, also called Lepeophtheirus salmonis or salmon louse, are tiny parasites less than 1.5cm long that are a cousin of the woodlouse. The lice attach themselves onto the skin, fins, gills, blood or tissue of the salmon to feed on them. The environment of salmon farms, which are designated, netted areas of the ocean, are prime breeding grounds for sea lice. These confined areas allow the parasites to spread more quickly.

“They’re only a couple of inches long, and the lice basically eat them alive,” Canadian based marine biologist Alexandra Morton told the New York Post about the young wild salmon currently being infested with lice from farmed fish from eastern Canada, Norway and Scotland. “The worst case scenario? Extinction of wild fish in the areas where there are these farms.”

Why Sea Lice Is a Bigger Problem Now

Sea lice on salmon. Credit: 7Barrym0re/Wikimedia Commons

The rise of large-scale salmon farming is what has caused the outbreak of sea lice in salmon to spike. Sea lice is not a new threat to the fatty fish; they have always fed off salmon, and it’s common for wild adult salmon to pick up the parasites in the ocean.

But since freshwater kills sea lice, the adult fish would shed the parasites when they returned to the rivers to spawn. Traditionally, there was also less contact between juvenile and adult salmon, so it would be harder for the parasites to spread to the young salmon. And while an adult fish can live with sea lice, a young salmon’s immune system is worn down in minutes by the parasites, making them vulnerable to infection. In addition, young fish can easily be killed by at least a dozen sea lice.

Related: Sorry Sushi Lovers, Your Salmon May Have A Japanese Tapeworm

A study says that man-made climate change, which led to warming sea temperatures, is also a major contributor as to why the pests have become more prevalent on fish farms in recent years. Both Norway and Scotland reported severe problems with the outbreak in 2016. Unusually warm temperatures also contributed to the 2015 sea lice epidemic that hit British Columbia, Canada.

Natural Ways Fish Producers Are Trying to Destroy Sea Lice

The Herald Scotland reported that Marine Harvest, a major international producer of salmon, tried to get ahead of the problem last summer, but accidentally destroyed 16 percent, or 1,500 tonnes, of the volume of the fish they produce in Scotland. The company tried to treat their salmon for lice using a thermolicer but inadvertently cooked and killed 175,000 fish. A themolicer works by immersing the fish in a warm bath.

Farmed salmon pens. Credit: Sam Beebe/Flickr, CC BY 2.0

Fish farmers, in an effort to avoid chemically treating the fish, are looking into alternate methods to control the salmon sea lice problem. Another option they are investigating is the hydrolicer. By bathing salmon in freshwater, the fatty fish are surrounded by cleaner fish that inhabit those waters— which include wrasse and lumpsuckers— that eat the lice.

Other non-chemical treatments currently being explored include lice-zapping lasers and large-scale pens. But new technology is pricey to develop and implement, even with government funding that is devoted to salmon farming countries.

Norwegian farmers are also using tarpaulin, which are “skirts” that sit around the upper parts of the sea cages containing the salmon. They prevent sea lice larvae from entering or exiting the cages. This year Scotland plans to pass new legislation to help curb the spread of the lice.

Chemicals Used to Destroy Sea Lice

Chemical treatments are the most common way to combat sea lice, and salmon farmers have been implementing them since the 1970s. They do this by using a synthetic pesticide called emamectin benzoate. Also known by its brand name “Slice,” the drug is fed to salmon, it seeps throughout the fish’s body, and then poisons all sea lice nibbling on its tissue. But because of farming regions that have built up a resistance to Slice and other chemicals, farmers have been known to use these substances in higher amounts. Scottish farmers now use 10 times more chemicals to combat sea lice compared to more than a decade ago. And Norway has relied more heavily on hydrogen peroxide baths for salmon, which has been a point of concern for the Norwegian food safety regulators.

However, because of the millions of dollars lost to the sea lice infestation (experts say it costs them around $550 million in lost output each year), salmon farmers are now exploring other options to fix the problem. Many have decided to invest in developing farms where sea lice cannot live and thrive. The Norwegian company Nordlaks is looking to avoid the tight fish confinement problem by creating a space for fish that is the nearly the length of five football fields.

The Fallout With Salmon Prices

Credit: Joe Mabel/Wikimedia Commons, CC BY-SA 3.0

The short supply of salmon has increased the demand for the fish — farmers in Norway sold 7.3 billion worth of salmon in 2016 — but because rising sea lice infestations are ravaging salmon farms, and farmers have the need to expand their production, the process of killing the parasites without killing the fish is becoming more difficult.

The NASDAQ Salmon Index says that the price of salmon has increased more than 15 percent in the last three months. Norway and Scotland saw the fatty fish spike by 50 percent because of the sea lice outbreak. This issue followed a short salmon supply shortage in Chile, the world’s second biggest producer of farmed salmon, due to a deadly algae bloom in the South American Country.

Related: New Guidelines Make It Easier for Pregnant Women to Eat Fish

Norwegian bank Nordea’s fish analysts predict the lice outbreak will get worse before it gets better. And that could cause global supplies of Atlantic salmon, which already fell 9 percent, to continuously drop. The biggest price increases haven’t affected consumers yet, but wholesalers and retailers — both domestic and international — are already feeling the pinch. They all have had to pay more cash out to afford salmon.

It’s gone up 50 cents to a dollar a pound just in the past weeks,” Lewis Spada, co-owner of Shelsky’s Appetizing and Delicatessen in Cobble Hill, Brooklyn told the New York Post about the surging wholesale salmon costs.

UK-based Billingsgate Fish Market trader Scott Unwin, of Bobby’s Fish, agreed, “It’s been crazy.”  He says not only have prices gone up nearly 50 percent over the past four to six months, but that salmon is in short supply. Adds Unwin, “I’ve been at Billingsgate 30 years and I’ve never seen it so bad.”