They look as appetizing as a cactus and taste like low tide, but not even that has been enough to keep New Brunswick's green sea urchins out of a prickly predicament.This was the lede to an interesting story on urchin overfishing in yesterday's Seafood News. The article goes on to explain the sea urchin fishery off of New Brunswick and how the Japanese penchant for sweet urchin gonads (sometimes called 'roe') are leading this urchin to an overexploited status.
[Green sea urchins] were once considered a nuisance by some of the same men who now pursue them. Indeed, lobster fishermen once reviled urchins for clogging their traps. But a large market for green sea urchins developed in Japan, which sent the fishery full throttle in a gold-rush approach around the world. The population now seems in decline globally. The article describes changes off the New Brunswick coast:
Ten years ago, New Brunswickers hauled in 1,911 tonnes of sea urchins with a market value of a little more than $4 million. In 2006, those figures fell to 916 tonnes and $1.8 million.
According to one Japanese survey, green urchin sushi is one of the nation's favorite, second only to fatty tuna (and we know what's happening to them). According to the article, [sea urchin] privates are said to have a sweet, nutty taste. Indeed, it is the gonads that are used to make the sushi the Japanese crave.
Aside from their sweet nuts, sea urchins also have the disadvantage of slow growth. It takes sea urchins nearly 12 to 15 years to grow to two inches, which is the legal minimum size.
In Galapagos at least, I know the endemic green urchins there cover themselves with shells to prevent sunburn. Here's the before:
And after (sea urchin sushi):
Environment
Comments
I've eaten uni sushi. "Sweet, nutty taste" is a pretty fair assessment. The closest analogue I can think of, both in terms of flavor and texture, is peanut butter, but with strong overtones of seaweed and fish oil and ocean smell.
It tends to go off rather quickly. I wonder how much uni is simply thrown away because it doesn't get eaten in time?
Posted by: HP | November 15, 2007 11:33 AM
This went on in Maine 15 years ago as local fishermen turned from declining finfish to urchins, and of course over-exploited that fishery.
Posted by: Randy Olson | November 15, 2007 1:46 PM
What I've heard is that many fishermen aren't too upset about finfish declines as lots of invertebrates (lobster, urchins, etc.) make more money than finfishes. This is worrying when fishing down the food web is more profitable. Also, urchin overfishing is just one warning sign against the many people saying we should be eating lower on the marine food web...
Posted by: Jennifer L. Jacquet | November 15, 2007 2:44 PM
However, in some places sea urchins should be fished to help restore the ecosystem. In many places in the Mediterranean, for example, the overfishing of predatory fishes has enhanced the population explosion of sea urchins. These now-abundant sea urchins devour the macroalgae and can turn productive, diverse algal forests into barrens with very low biodiversity, biomass, and resilience. In this case, removing sea urchins would help bring back the algal forests and also provide the conditions (food, shelter) for the fishes to come back (if we created marine reserves).
Posted by: Enric Sala | November 15, 2007 3:31 PM
Excellent point. So why have an overfished fishery off of New Brunswick instead of a thriving fishery in the Mediterranean? What's stopping Japanese demand from infiltrating the Med?
Posted by: Jennifer L. Jacquet | November 15, 2007 3:38 PM
I have been asking myself this question for a long time, and do not have an answer. Sea urchins are appreciated by some locals in the Med, but they are not exported to Asia. Maybe their gonads are too small compared to those you can find in sushi restaurants and they are not appetising to the Japanese? The taste is good, though
Posted by: Enric Sala | November 15, 2007 3:54 PM