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Sturgeon: Living Fossils

Few species on the planet have remained unchanged for millions of years, the sturgeon is one such beast. These armoured giants first appeared around 175 million years ago and are known today for their valuable eggs or "caviar."

All forms of caviar are named after the fish they come from. The king of caviar comes from the beluga sturgeon in the Caspian Sea, who produces soft, large eggs that come in pale grey-silvers to blacks. Second in quality is medium-sized osetrova, which comes in greys, green, and black, followed by the smallest sevruga, which are greenish-black. The sterlet produces a very rare gold caviar which was once reserved for Russian Tsars. Other types include Chinese Kaluga and American osetra.

Photo sourced from Pinterest

There is often controversy surrounding the egg harvesting methods, as some involve stunning or killing the animal, and removing the ovaries. New processes have been developed including caesarian sections which allow the fish to continue producing roe, and "stripping," which involves a small incision made along the urogenital muscle when they are ready to be processed.

A German scientist named Angela Kohler spent nine years developing a the "Vivace no-kill" technique at a small farm in Loxstedt in which eggs are viewed by ultrasound prior to harvest, then a signalling protein is administered to induce labor, releasing the eggs in the belly, at which point they can be gently massaged to collect. This process can be done every fifteen months or so. There are varying opinions on the quality of caviar this produces, some believe it ruins the "Caspian pop," or snap in the mouth when eggs are bitten, leaving them overly oily and soft.

Northern Divine Aquafarms in Sechelt, British Columbia is the first producer of organic sustainable caviar in North America - using only pure, refined Canadian salt during curing. Raising their Fraser River Sturgeon (second in size only to the Beluga) in land based farms, with no antibiotics or added hormones, this company utilizes not only the fish eggs but the entire animal. You can even purchase dehydrated tails as a treat for your dogs.

Both the caviar and flesh from these farms is prized by top chefs not only in the Vancouver area, but around the world.

Photo from Northern Divine.

Caviar has been served since the 4th century AD, recorded in accounts from Aristotle. The Romans believed it an aphrodisiac which also increased life expectancy, and King Henry I of England declared it a "royal fish," with King Henry II issuing a decree that any caught are property of the crown - a law which survives to this day. Of course it has also been a long standing delicacy with Russian Tsars, due to their proximity to quality stock.

Prior to serving caviar, ensure it is kept cold in the provided tin. Remove from fridge 15 minutes before serving. Connoisseurs believe metal destroys the eggs' delicate flavor, so it is traditionally served in a chilled crystal glass over ice, using a bone, horn, or mother of pearl spoon. Of course not everyone stocks these items in their kitchen, so any glass dish and plastic spoon will suffice.

The best caviar is spooned directly into the mouth. A good rule of thumb is to serve less accoutrements as the quality of caviar increases. Outside of this, caviar is often served on top of blinis, a small Russian buckwheat pancake, or with a side of crème fraiche and lightly buttered toast (throw a couple drops of vodka in the butter for added depth of flavor). Quail eggs or raw onions easily accompany either of these combinations as well. In terms of beverage pairings, you would be remiss if you drank anything but champagne or vodka.

Of the 29 species on Earth all live in the northern hemisphere, most are anadromous, spawning in fresh water while feeding and migrating along coastlines. Sturgeon can be found in three major drainages of British Columbia, the Sacramento River, Columbia River, and Fraser River. The White Sturgeon or acipenser transmontanus, which translates to "sturgeon beyond the mountains," used to be found in abundance from Alaska to Monterrey, California.

They are listed as endangered in Canada, and great lengths are being taken to protect the remaining populations. Probable causes of this decline are hydroelectric dam construction, industrial pollution, and over-fishing. The sturgeon is particularly sensitive to environmental effects due to their slow rate of maturity, they do not spawn until they are fifteen to twenty years old. Alongside this they do not spawn every year, as they require exactly the right conditions: clear water with shallow rock or gravel, appropriate temperature and oxygenation.

Average lifespan can be fifty to sixty years, in which time they reach immense size, 2-3 1/2 meters in length. The largest on record was a beluga found in the Volga estuary of the Caspian Sea, weighed in at 1,571kg (3,463lb).

Photo from Times Free Press

Outside of North America, sturgeon are found most abundantly in the rivers of Southern Russia and the Ukraine, where the wild populations were nearly fished to extinction before a strict fishing ban was put in place from 2008 to 2011.

Despite their intimidating size sturgeon actually have toothless mouths, and utilize four barbells - a small whisker-like sensory organ - to find small fish and crustaceans along river bottoms. Their form is all the more unique due to five rows of bony plates, or scutes, that partially cover the body instead of scales and an almost fully cartilaginous skeleton.

A behavior of these aquatic Methuselah's that still baffles scientists is their full leaps out of water. Some potential motivations include mating display, group communication, shedding parasites, or even just because it feels pleasant. The resulting slap against the water can be heard miles away. While sturgeon are a non-aggressive species, due to their size if a leap occurs near a boat it can cause unintended damage.

This great creature is no threat to us, but we are to them. Consumption in any form, of the eggs or flesh, needs to be approached with awareness. Stick to Oceanwise (Canada) or Seafood Watch (USA) guidelines and eat in moderation. If you are an angler ensure the correct permits are acquired and stick within legal fishing locations, season and methods. In British Columbia most sturgeon are protected under the Species at Risk Act, the only regions that allow catch-and-release recreational fishery of sturgeon are the Lower and Middle sections of the Fraser River.The rule of "respecting your elders" should extend to all species, particularly those 97 times our senior.