Skrei - secrets of the Norwegian Arctic cod stock

“Cod is best during the winter. Of course, you must’ve known that, coming from Newfoundland?” I was with my Norwegian colleague Egil at the university I work at in Trondheim. I returned his question with a blank stare. During much of the winter in Newfoundland, the cod fishery is typically closed. And in terms of flavour, the winter season cod was nothing to write home about. So what was he talking about? Egil, taking my blank expression as his cue, launched into a lesson with a seafood lover's zeal. “The cod is spawning at this time of year. We call them skrei. They are full of health, full of flavour, and - most importantly - full of roe. It’s traditional to boil the cod and serve it with its roe and liver. It’s a meal for celebrations!”

I was totally stunned. Same fish, different side of the pond. So why is the spawning cod available in one fishery but not the other?

This post is about rediscovering a fish that I was practically raised with in Newfoundland. I look into the “skrei” fishery, which refers to the unique Northeast Arctic cod stock - which represents world’s the only remaining sustainable cod fishery. I also share a great recipe that I've tested over the past several weeks for poached cod with its roe and liver, prepared in the traditional Norwegian style.

A fishing boat outside Ålesund, Norway

It was a sunny Friday afternoon and immediately after my seafood lesson from Egil and walked from the university to my local seafood shop, the resplendent Ravnkloa, to check out the skrei for myself. And there they were: strikingly large cod fish, lighter in colour than usual, presented on ice behind the glass counter and cut part way into steaks. They were sitting next to a large tray of membranous roe pouches and another smaller tray piled high with gelatinous liver. Amazing!

Three large skrei cut into steaks and displayed at the Ravnkloa fish market. Next to them (left) are skrei fillets; left of them are three trays containing (top to bottom) cooked cod's roe, cod tongues, and cod livers. Next to them (left) are the membraneous pouches of fresh cod roe.

Trondheim, Norway. The fish shop Ravnkloa (right) has become my favourite local institution.

Why no skrei in Newfoundland?

The first thing I wanted to know was why spawning cod was not available back home in Newfoundland. There cod is so ubiquitous that it’s usually just called “fish.” This was an especially poignant question considering the cod was supposedly at its peak flavour during spawning season and its roe and liver were generally held as delicacies. The liver highlights a notable difference because I was used to throwing this toxin-collecting organ overboard for the seagulls at my local fishing grounds in Newfoundland. A healthy liver would denote a health fish. So what’s the deal? Why have I been missing out during all those years in Newfoundland?

After some investigating, I learned that the answer to the question of availability of spawning cod in Newfoundland is twofold. Firstly, the island's cod fishery is, for the most part, closed during spawning season due to sustainable management practises. It's hard to deny that that’s a good thing. But it begs the question as to why the Norwegian fishery doesn't adopt a similar strategy. And this is where things get interesting. The secret, it turns out, lies in a special stock of cod. Technical speaking, it’s the same species as the cod found in Newfoundland (Gadus morhua), but this stock is special for its distinctly wandering spirit. The Northeast Arctic cod stock, as it is called by scientists, leaves the coast and swims far into the freezing Barents sea, returning in astounding abundance to mark the start of spawning season in February and March. The fecundity shows in the official numbers: the fishery is considered sustainable and their numbers - and even individual fish sizes - are actually growing. This is particularly striking considering that cod has long been the poster child of unsustainable fishing practices - perhaps nowhere else as much as in Newfoundland.

Skrei, fresh

Cod roe, fried in butter after being poached

Cod liver, fried with onion

Consider it an evolutionary advantage: if a change in environment hurts one population and benefits another, the species overall is still in good shape. Marine biologists call it a "portfolio effect," so-called because risk is reduced in spreading out your investments, much like in a financial stock portfolio. In Norway the coastal cod stock is in trouble. The migratory Northeast Arctic cod, however, appears to be actually benefiting from changes in its environment. Today it’s the largest cod stock in the world. Sweeping changes brought on by climate change may be part of the reason. A healthy ecosystem in the Barents Sea is also partly to thank. We would be remiss, though, not to also acknowledgement the clever fisheries practises on the part of the Norwegian government, too: a rare example where astute scientific management and good communication between fishers and scientists has resulted in a success story.

In Newfoundland, the cod fishery infamously suffered a devastating crash and subsequent total closure in 1993-4. When it slowly started to re-open in the subsequent decades, the fishery operated under close monitoring from the Department of Fisheries of Oceans (DFO). The Canadian government maintained that scientific management would be the only way the fish would have a hope of one day returning to commercially viable success - even if that meant throwing many thousands of fishers into unemployment. The management plan includes a definitive closure of cod during spawning season. The intent, as explained on DFO’s website, is to “minimize the disturbance during cod spawning in case such disturbance might negatively affect spawning success.”

Fisherman in Trondheim, Norway, selling fresh fish on a cold winter morning.

Cod's big comeback

It was questionable timing when, in 1993 - the same year that the Newfoundland government announced the moratorium of its cod fishery - a local scientist named George Rose published an article in Nature shedding light on the spawning habits of the Newfoundland Atlantic cod. Despite over 500 years of fishing history, Rose argued that embarrassingly little was known about the spawning behaviour of the Newfoundland cod stock at a time when this knowledge was sorely needed. The paper marked a breakthrough, linking observations with theory. “Highways” of cod were discovered during migration, where schools hundreds of millions buddy up and travel along the Grand Banks, making them vulnerable to overfishing using modern trawling techniques (many of whom also use a now-outlawed technique called Buddy-up). The paper ended on a dark note: “for Newfoundland cod, migration patterns may be expected to change, perhaps irrevocably, in response to population declines in the early 1990s.”

My local cod fishing ground in Newfoundland during the summer fishery. "Line up the stacks" of the Holyrood power plant in Conception Bay and the fish appear.

Two decades later, though, and the same scientist, now a leading authority on cod and an authour of a 2008 book about the flagship fish, has returned with more buoyant news about the state of the fishery. In a 2015 paper entitled “Northern cod comeback,” Rose writes what many a Newfoundlander has dreamt of writing: the fish are coming back.

“The great northern cod stock, formerly among the world’s largest and the icon for depletion and supposed non-recovery of marine fishes, is making a major comeback after nearly two decades of attrition and fishery moratorium.”  - George Rose, leading fisheries scientist

Of course, we must fight the temptation to say that the cod problem is solved. In 2017, Rose warned the Canadian government not to ramp up the cod fishery at the first signs of a recovering stock, presenting a strong argument in another Nature article. In a 2018 interview Rose stated that numbers are, in fact, down once again, in no small part due to an overzealous "cod fishery transition." And so we continue to wait with baited breath about the fate of the Atlantic cod, buoyed by early results of a slow recovery, yet mindful of our trigger fingers on fish quotas. May we at least consider this: a dinner table decked out with poached cod steaks along with its rich roe and liver - a meal for celebrations, marking abundance during a time when fresh food is scarce, hailing the miracle of a fish brimming with vigour and fecundity. Let's consider it, because it exists!

Trondheim, Norway, where I currently reside.

Poached skrei (spawning Northeast Arctic cod) served with its roe and liver

Ingredients
(Serves 4)

4 skrei steaks (about 800-1000 g)
1 quantity roe (about 400 g) in its membrane, wrapped in parchment
1-2 livers (about 400 g) cut into small chunks
1 onion, red or yellow, finely sliced
Butter
Distilled white vinegar (6-7% acetic acid)
Lots of mineral salt
Pepper

Norwegian butter-and-parsley sauce (Sandefjordsmør)
200 g butter, cold and cut into small cubes
50 mL cream
1/2 lemon
Bunch of fresh parsley, finely chopped
Salt and white pepper

Method

If you have the time, place the cod steak in cold, fresh water for at least 2 hours before poaching. This adds a tenderness to the cooked flesh.

For the potatoes and roe

In a large pot, bring a large pot of heavily salted water to a boil (I’ve found 50 g of mineral salt per 1 L of water is sufficient). Wrap the roe in parchment paper so that the ends are tucked in and it won’t unravel. Place the wrapped up roe in the boiled water. Meanwhile, in a second large pot, boiled the potatoes for approximately 25 minutes or until one falls off a fork when tested for readiness.

For the skrei

Prepare a third large pot for the skrei. Get it going on a heavy boil and add lots of salt (use 50 g per 1 L of water) along with the vinegar (1 tablespoon per 1 L of water). Remove the water from the heat and immediately add the cod so that they cook in the residual heat. Set a timer for 10 minutes.

For the liver

You have two options: fried or baked. Both are good, but I think I prefer baked. For the former, sauté with onion in plenty of butter for about 4 minutes on a medium-high and then add the liver. Stir gently as it cooks in its own rich oils. Add 1 tsp salt and pepper to taste.  For the latter, placed roughly chopped chunks into a casserole dish along with the onion, some chunks of butter, and salt and pepper. Bake for 40 minutes at 180C.

For the sauce

Norwegian butter and parsley sauce (Sandefjordsmør) takes about 10 minutes to prepare and is best served fresh and not reheated. Try not to heat it too much or you’ll break the emulsion of lemon and butter.
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Bring the cream up to a medium heat in a small saucepan. Add the butter one cube at a time, whisking all the while. When half the butter is used up, take the sauce off the heat and whisk in the lemon juice.

Keep whisking while adding the butter, one cube at a time. Season with salt and pepper, then add the parsley and serve fresh.

Helpful tips from the fishmongers at Ravnkloa. I found 25-30 minutes to be more suitable for boiling cod roe.

Cod roe wrapped in parchment, about to be boiled

Cod liver cooked with onion and garnished with parsley, served with poached skrei (top right) and poached cod roe (bottom right)