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Remote Setting (Part 1) The larvae of several commercially important bivalve species lend themselves to remote setting, most notably oyster larvae and, to a much lesser extent, clam larvae. What follows is a description of remote setting with Pacific (or Japanese) oyster larvae (Crassostrea gigas). Remote setting of larvae of other bivalve species can be (in most cases is) more demanding. Although remote setting has been essential in sustaining very high oyster production levels of Pacific oysters on the U.S. and Canadian West Coast for decades, the outcome of a remote setting effort by a grower is never predictable. Even the most experienced grower faces uncertainties. As such, remote setting adds to the fact that nothing is, or ever has been, easy in the oyster business. Since it all starts at a shellfish hatchery, let's go there first. Welcome to "Whoville" Pioneering work in successfully completing
oyster development from a larval to early post-larval state in
volume in a closed, controlled environment on a small scale can
principally be attributed to W. F. Wells (1920 Some large shellfish growers operate their
own hatcheries to insure their stocking needs and sell surplus
seed to other, typically smaller shellfish growers. Various universities
also maintain sophisticated hatchery operations. Although such
hatcheries usually focus on research and training, some are capable
of producing commercial quantities of seed. Spawning at the hatchery When it is time to fill an order from a shellfish grower, the hatchery operators filter batches of fully developed ("footed" and "eyed") oyster larvae from the water in their rearing basins. There are various ways to strain and count all these larvae. Even coffee filters have been used at times in the straining process of bivalve larvae. The larvae can then be centered on a small, porous fabric square that sometimes looks as if cut from an ordinary white bed sheet. The sides of the fabric square are then turned up, bunched at the top and banded, thus rendering a larvae package in the shape of a little ball. Such a ball with two million oyster larvae measures about the size of a golf ball. Once this procedure is done, time is of the essence. The larvae, now out of water, must stay moist and cool. Depending on the grower's order, one or several of these balls may have to be shipped promptly at the same time. In a small, Styrofoam lined box, the larvae balls are then bedded on all sides in moist paper towels or newspaper, along with one or more small cooling packs. A reliable overnight courier company then transports the larvae to the oyster grower.
Today, at least half of the C. gigas
larvae produced by shellfish hatcheries worldwide are triploid.
The reader might wonder why any grower would buy diploid larvae
and seed when triploids appear to be so commercially advantageous.
There are a number of reasons that could prompt a grower to choose
triploid oyster larvae or seed over diploid. Some growers appreciate
the potentially substantial natural sets the diploids can produce
in addition to the seed growing and remote setting a grower employs.
After all, it is a well known fact that, for millennia, the extraordinary
fecundity of oysters has been their recipe for survival. One
grower advised that juvenile triploids simply did not survive
on his tideland while diploids did. The principal of a large
U.S. West Coast shellfish growing company recently informed me
of excessively high mortality levels among his three to four
year old C. gigas triploids. Many growers in France have
blamed triploid oysters as the underlying reason for the recent
outbreak of a devastating, herpes-like disease among one to two
year old Pacific oysters in recent years. Some buyers who are
firm adherents of the tenets of organically grown food simply
don't want triploid oysters. They don't believe that mass production
of triploid larvae and seed is natural - and they are correct.
When, not if, oysters achieve a formal organic qualification,
I feel certain that triploid oysters will not be acceptable -
no more than oysters raised on tideland that has been sprayed
with pesticides (a long-standing practice of big oyster growers
on Willapa Bay in Washington State to kill indigenous mud shrimp).
William W. Budge For online searches of U.S. American patents and trademarks, the United States Patent and Trademark Office (https://www.uspto.gov) provides several powerful search utilities. Most bountiful (and very fast) patent searches can also be conducted via https://www.google.com/patents. Thousands of oyster-related U. S. patents exist. The reading of just a small fraction can easily keep an oyster aficionado engaged for many hours on end. The mixture ranges from brilliant ideas to blatant opportunism, devoid of any ingenuity. Someone hoping to develop or further some new method or design that could actually be of great value to others might grow discouraged when trying to navigate this jungle of preexisting patent claims to avoid potential infringement. Oftentimes, talented attorneys have applied their formidable wordsmithing skills to the descriptive language of patents, thereby expanding the coverage of patent protection to the outermost limits of what might be called "interpretative clarity". For example, in an excellent report on cultchless oyster setting back in 1981, the researchers Herbert Hidu, Samuel R. Chapman and David Dean devoted an interesting paragraph to the discussion of the associated legal minefield. The paragraph ends as follows: "[…] It is literally impossible
to rear a cultchless seed oyster without infringing on someone's
broadly stated patent. Unfortunately, the The results of my search of William W.
Budge (commonly called Bill Budge) and Pacific Mariculture suggest
that he was a brilliant and dedicated scientist who served as
the president of said company. Back in the 1960s and 70s, Pacific
Mariculture worked on the cutting edge of marine aquaculture,
primarily in the area of abalone cultivation and secondarily
in oyster cultivation. An online publication titled "ADVANCES
IN THE REMOTE SETTING OF OYSTER LARVAE", prepared by Gordon
and Bruce Jones, funded by the Aquaculture and Commercial Fisheries
Branch of the British Columbia (BC) Ministry of Agriculture and
Fisheries Part 1 Part 2 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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Inset
image: A news blurb touting The Pedigreed Oyster in the
Reading Eagle, March 18, 1927 (found in Google News Archive).
) and H. F. Prytherch (1924
, 1937
). They built on and completed the remarkable research
of W. K. Brooks (1891
)
and others. Large scale, reliable hatchery production of larval
to post-larval oysters (C. virginica) was not perfected
until the 1960s. Although Paul S. Galtsoff
and Victor Loosanoof
are usually associated with this success,
there were numerous other naturalists that greatly contributed
as well. In the 1970s, shellfish hatcheries rapidly expanded
from the U.S. East Coast to also include the North-American West
Coast. Since then, many more shellfish hatcheries have been built
worldwide. In 1979, a detailed account of the history of shellfish
hatcheries titled Oyster Seed Hatcheries on the U.S. West
Coast: An Overview was furnished by J. W. Clark and R. D.
Langmo.
, diploids,
3 - 6's". The first part of the label's lower text, highlighted
with a red square in the inset image, indicates the total amount
of larvae in this shipment. The timely Federal Express man can
now easily trump 
any braggartry among his colleagues by validly claiming
to have, single-handedly, transported eighteen million live oysters.
practical standpoint of a grower, the
diploid post-larval oysters (i.e. after metamorphosis) are likely
to grow at about the same rate that wild oysters would and, when
reaching maturity, would be able to reproduce. In moderate climates
with a fairly warm summer and fall, the oysters, when preparing
to spawn, would often have a "milky" consistency and
later, after spawning, their meat could seem sunken-in (a temporary
condition called spawned out). Although such meat conditions
are irrelevant to cooked oysters, many half-shell oyster lovers
do not much care for "milky" or "spawned out"
oysters. 
Tennis
Balls Instead of Golf Balls
Subsequently, the hatchery had to utilize
a piece of fabric measuring about 24 x 24 cm (~ 9.5 x 9.5 inches)
for each ball. The Olympia Oyster Company operates three large
remote setting tanks. Each tank requires six million larvae for
remote setting.
,
furnishes some details of Budge's pioneering work in remote setting.
In combination with his according U. S. patent # 3,735,737, I
find it reasonable to honor William W. Budge as the "Father
of Commercial Remote Setting of Oysters". 