Opening Oysters


Classic Method
Clever Method
Commercial Method
Clumsy Method
Oyster Knives

Commercial Method
John McCabe

The following describes a very common commercial method of opening oysters. Most of the oyster meats we buy at the seafood market in pint or gallon containers were pulled from their shells (shucked) in this way - one by one. This commercial method works with every culinary oyster type. Depending on oyster size, professionals can shuck anywhere from ten to twenty gallons of oyster meat per day. Even the tiny Olympia oyster is shucked in this way. It takes about 250 of them to fill just one pint. Although mankind has proven to be able to fly to the moon and build weapons that can easily destroy our entire world, no machine has ever been designed that can replace commercial oyster shuckers.

Inset image: Oyster shucker opening marker (or "token") from the 1950s. Markers of this type, either in steel or brass were once commonly used on both the American West and East Coast. They are highly collectible. Measurement on this marker is in centimeters. The number denoted the respective shucker. The marker was added to each gallon of oyster meat processed. This one originates from the Bendiksen oyster plant which operated on Willapa Bay at the town of Nahcotta, Washington. Old man Bendiksen is now an important historical figure in those parts. Many of the oldtimers out there still remember him well as one tough oysterman. He worked hard in his plant clear up until his death (died in his eighties).

* Essentially an easy opening method. What makes it difficult is maintaining the speed it requires to produce a large volume of oyster meat in the course of a work day and the consistent accuracy necessary to precisely sever a part of the bill of the oyster shell for hours on end without stabbing one's hand instead.
* Large quantities of meat from any type of oyster can be gleaned with great efficiency (presupposing experienced shuckers).

* Oysters opened in this manner are not suitable for half shell trade. The shells are rendered highly unattractive. They are initially discarded right after opening, then gathered and piled high outside the shucking facility, gradually become naturally weather bleached over time, and are later reused in the oyster cultivation process as so called cultch (for little oyster babies).
* Shell splinters are unavoidable. The oyster meats need to be thoroughly washed after shucking.
* The processing monotony and constant banging noise of pounding blades starts to weigh on the soul after many hours of shucking. There are always more oysters pushing down in the stainless steel chute waiting to be processed - with seemingly no end in sight.

Image: Professional oyster shuckers hard at work. The work rooms are climate controlled and kept cool. The shuckers constantly receive a seemingly endless supply of fresh oysters from a line of gravity fed stainless steel chutes.




Image:The oysters are opened at an astoundingly rapid pace. After each oyster is opened, its meat ends up in a large stainless steel bowl. All the meats are then thoroughly washed and sorted for size in other work areas.




The following pictures are simply a few I took at home to demonstrate how the method essentially works. Just imagine sturdy rubber gloves, thousands of oysters coming at you from huge chutes, a dozen guys and gals working next to you, the sound of many blade tips constantly pounding into hard oyster fortresses, and countless oyster meats being scraped into big stainless steel bowls.

Right about there looks good to chop off a piece of this large Pacific oyster's bill.





My kitchen table is not sturdy enough and my aim with the oyster knife tip is not good enough, so I'm taking it nice and slow.



In goes the blade to cut the adductor muscle located inside and to the left.





Off comes the shell. After cutting the base of the adductor musscle as well, the big chunk of oyster meat is ready to be moved into a bowl.




There are a number of important tasks that precede the commercial oyster opening process. They vary due to the different ways oysters are cultivated and what oysters end up looking like at the time of harvest. Following the primordial call to start forming reefs, oysters that are left to their own devices for three to four years in regions where they naturally reproduce will frequently grow into clusters. Subsequently, an oysterman will end up with a bunch of big chunks, each one of which will contain many oysters of varying shape and size - glued together and bizarrely entwined in a way only oysters understand. To make sense of such an oyster chunk in the commercial sense of gleaning as many marketable oysters as possible with the least amount of waste of product and time takes experience - and plenty of it. This is called culling. Professional culling it is every bit as important as professional shucking - and requires the same or more skill.

Image left: A typical oyster clump - in this case Pacific oysters. It weighs just a tad over one pound. A clump of oysters is not so unlike a big gemstone in the rough. With well contemplated cuts, a skilled gemstone cutter will turn any crude gemstone rock into several precious jewels. Conversely, an unskilled cutter will quickly ruin nature's bounty permanently. Essentially, the only difference between a good gem stone cutter and a good oyster culler is time. An oysterman has to skillfully process many of these oyster clumps very quickly. Some have been known to process hundreds of these clusters in a day.


Culling has reduced the clump pictured above into eight oysters (two large three year olds, three two year olds, and three yearlings).



Culling Hammers
A culling hammer is not used to open oysters. Instead, it is a precision tool used to eliminate empty attached shells and separating marketable oysters from oyster clusters. This process, called culling, is performed at a fast pace - ideally without damaging the marketable oysters desired. Equally, a professional culler will keep the destruction of the small "seed oysters" ("oyster babies" that are usually also attached to the "oyster clump") to a minimum. These little ones can be left behind on, or be returned to the harvested area to continue to grow to marketable size. Also, a culler may have to observe some minimum legal harvesting size that may be in effect in some regions. Culling hammers have a long history, most notably in the context of Eastern oysters (Crassostrea virginica) and to some extent Pacific oysters (Crassostrea gigas).

Historically, these culling hammers (and all other types of culling tools) have turned up in many shapes and sizes. They often started out as varied hammer types such as roofing hammers, small mining hand picks, ball peen hammers, riveting hammers, setting-down hammers, etc., or other suitable tool types. These were then customized to optimize their function as oyster culling tools. Culling hammers are usually fairly light weight with a good hand feel so that they can be used for hours on end. Frequently they look crudely made. Usually they are tailored to work best with the most prevalent types of oyster clumps encountered in a particular oyster harvesting area. Hence, there never existed an "official" design for a culling hammer.

Case Study: Culling Hammer from the Chesapeake Bay
The pictured hammer is a classic Eastern U.S. culling hammer design (click image to enlarge).
 Weight  275 g (10 oz)
 Length  314 mm (12 3/8")
 Head  108 mm (~ 4 1/4")
 Head Diameter  9 mm (3/8")
 Wood Handle Length  110 mm ( ~ 4 3/8")
 Handle Diameter  30 mm (~ 1 1/8") Wood round stock

Once commonplace on the Chesapeake Bay, these hammers have since become rather scarce collector items due to the dramatic decline of Eastern oyster stocks since the 1950s (due to over-harvesting, oyster diseases Dermo and MSX, and pollution). I bought this particular hammer from an acquaintance of a blacksmith by the name of Jack Swift, who operated one of the last (perhaps the last) blacksmith operations "on the shore" geared almost exclusively to the shellfish business (knives, rakes, tongs, hammers, dredges, etc.). The shop was located in the famed little town of Crisfield, Maryland.
This hammer likely dates back to some time around the mid 20th century. It is made of carbon steel and features a round wood handle. The inside diameter of the shell gauge (two steel bars over/under) measures exactly 3 inches (or 76 mm; min. harvest size). One end of the head's 3/8" round stock steel was worked downward starting at 1.5" (or 38 mm) from its end with a gentle slope of about 8° (detail pic. here). At about the half inch point (approx. 15 mm) down the slope, this head-end gradually begins to flare, culminating in a width of 5/8" (approx. 16 mm) at its flat tip (detail pic. here). From the same point as on the upper side (1.5" from the end), the round underside was ground flat (no slope). The duck-bill shaped end is slightly convex. The wood type of the round-stock handle is not known to this writer. Aside from some light and even surface rust, the functional condition of this very robust hammer is "good as new".

Case Study: Oyster "Cluster Buster" from the Willapa Bay
The pictured culling tool (click to enlarge) was custom made by Larry Warnberg, a remarkable (and now retired) oysterman from Nahcotta, Washington (Nahcotta Oyster Farms). Much like the new owner of Larry's operation still does, Larry specialized in organically grown Pacific oysters (i.e. no pesticides like Carbaryl permitted on his oysterbeds etc.). He utilized a variant of so called pole cultivation. For more than twenty years he would harvest countless three to four year old oyster clusters that formed on a pattern of thousands of three foot PVC pipes he had driven into the tide-flats about a foot deep. I stopped in many times over the years for two reasons: 1. To buy a bunch of his delicious oysters which he was selling at the best price per dozen I could find anywhere; and 2. Larry always made time to answer a bunch of my detail questions about the oyster industry on the Willapa Bay. Usually, while talking with me, he went right on "busting oyster clusters" with the pictured tool with amazing speed, accuracy, and very few damaged oysters - all the while sorting small, medium and large sizes. Windy, rainy, ice cold weather did not seem to change his fast pace or consistently good attitude a bit. One day, I asked if I could buy one of his "cluster busters" for closer analysis (I simply made up the informal name for this tool as it does not have any formal name besides "culling tool"). He proceeded to just give me one of them. Some specs on "Larry's Cluster Buster":

 Weight  285 g (~ 10.5 oz)
 Tool Length  192 mm (~ 7 1/2")
 Handle Length  90 mm (~ 3 1/2")
 Handle Diameter  17 mm (~ 5/8"; as measured from flat to flat of hexagon)
 Prying Shaft Length  175 mm (~ 6 3/4")
 Prying Shaft Diameter  10 mm (~ 3/8")

The tool is made entirely of austenitic stainless steel. The handle is made of hexagonal bar stock which rests firmly in the palm of the hand. The prying shaft is welded perpendicular to the handle at its center. The tool subsequently locks in a fist grip on either side of the middle finger. Wrist action can pilot the tip of this culling tool at an infinite amount of angles and bring considerable force to bear if needed. The round stock 3/8" stainless of the prying shaft was ground equally at top and bottom starting at 1.5" (or 38 mm) from its end with a gentle slope on the top and bottom side of about 4°, culminating in a flat and rounded tip.This culling tool seems indestructible.

Cluster Shucking
Instead of culling an oyster clump first, some skilled shuckers can efficiently process entire clumps for meat. This is not uncommon in so called "longline cultivation" where oyster clumps ready for harvest are cut from a long line (typically a three strand polypropylene line strung out intertidally atop many posts for about 100 to 200 meters).

There are different types of longline cultivation. A typical longline is manually populated with many oyster shell halves (called cultch) at intervals (commonly about 20 cm apart). Shells "woven" into these lines in the pictured manner stay locked in surprisingly well upon completion. Shell halves with lots of oyster babies (called spat) can be purchased from commercial shellfish hatcheries (the finished product being called spatted cultch). Equally, many longliners spat their own cultch by buying "eyed oyster larvae" from hatcheries and then "spatting" their own empty shells in temperature controlled water tanks.

Inset image (click to enlarge): Here we see a processed longline cluster of Pacific oysters aged about three or four years old. The cluster was cut from the line and perfectly shucked. The entire clump originally started with a single spatted shell. My count of shucked oysters in this particular clump was ten.

Dragging describes a method of breaking up oyster clusters with a harrowing tool which is towed over oyster-beds by a boat. The method is used in bottom cultivation. The tool is called a drag and functions much like a spring-tooth harrow in conventional agriculture. Dragging is typically performed during the second or third year of growth, right about the time the clusters have grown quite large and have become increasingly silted in. The drag lifts oysters up out of the mud and breaks their clusters into smaller clumps. The oysters then fall back to firmer ground for fattening up until harvest time (which usually occurs a year or two later). Dragging is quite common on Willapa Bay in the State of Washington. Several large bottom cultivators there utilize their oyster dredging vessels for dragging by temporarily substituting the dredge baskets with drag tools which they hang on the outrigger cables instead. Much like dredging, dragging requires considerable skill on the part of the boat operator, particularly since the (expensive) drag tool is a large, unwieldy and heavy piece of equipment. Drags are usually made of carbon steel. They require considerable maintenance. Corrosion (rust), bind-ups and abrasion are constant marine companions during use, transport and storage (click image to enlarge).

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Health advisory: There is a risk associated with consuming raw oysters or any raw animal protein. If you have chronic illness of the liver, stomach, or blood or have immune disorders, you are at greatest risk of illness from raw oysters and should eat oysters fully cooked. If you are unsure of your risk, you should consult your physician.

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