By Dr. Alexander J. Godknecht
The spiny dogfish (Squalus acanthias) is an endangered species and winds up on our
plates as rolled strips of smoked dogfish and dogfish sides.
© Shark Info / J. Brümmer
The regular spiny dogfish, scientifically known as Squalus acanthias,
is probably just as well- known to us as his larger relatives the white shark, the mako or the
However, he is most likely better known under culinary synonyms such as "rolled strip
of smoked dogfish" plain dogfish or as the fish found in "Fish &
Chips" menus. On our menus it appears primarily as smoked, braised or cooked and few
people realize that the fish on their plate is really shark meat. "Enjoy" your
last strip of smoked dogfish since very soon our menus will be shortened by some lines and
some fish dishes will disappear from our kitchen. Smoked dogfish strips will disappear like
the dodo and the giant tortoise, for very soon we will have eaten their last remaining
Spiny dogfish populations have been exploited for
many years. Those supplied for our kitchens have almost been exterminated in their European
habitats, the eastern Atlantic, the North or East Sea, where they are more coincidental
catches. The best spiny dogfish meat is imported from overseas. Fresh or frozen, the fish is
transported by air, for example from the east coast of the U.S. or Canada. Germany alone
imported an average of 1,700 tons of spiny dogfish annually until 1998. But this tonnage can
be misleading and is shrinking at an alarming rate.
A constant catch quota is considered an indicator of intact populations.
Many fishing authorities argue along these lines although in reality they really should know
better. A certain tonnage always consists of individual fish and depends directly on their
size and weight. From this point of view 1,700 tons are roughly equivalent to 740,000 spiny
Until recently, fishers of spiny dogfish practiced selective fishing in the U.S., with the
mesh size of their nets determining the size of the animals caught. This was the only way to
satisfy market demands which dictate that a "real" spiny dogfish should weigh
approximately 2.3 kilos and should measure about 83 cm in length (corresponding to an
average-sized large, mature female).
Fresh dogfish and rolled strips of smoked dogfish.
Both will soon be an expensive rarity.
© Shark Info / J. Brümmer
But what happens when this size can no longer be delivered. Fishermen are not considered
real fishermen unless they can satisfy demands, for essentially they live off the sale of
their catches. Essentially, this means that you supply the market with smaller-sized fish.
The consequences are disquieting. "...Previously, one dogfish side sufficed to make one
smoked rolled strip, today it is often necessary to combine two sides in order to reach the
required market size,..." complained Jens Brümmer of the fish smoking company G.
F. Wendt GmbH in northern Germany. "...obviously this method cannot be used with the
culinary dogfish, which means that smaller samples are being marketed.
If the number of average-sized sharks is reduced by
about 20%, at least 185,000 more spiny dogfish must be caught to simply reach the 1,700 tons
for the German market. The smaller the shark, the larger the quantity of catch must be,
which in turn also means that more and more young and sexually immature animals will be
caught. This is especially critical for spiny dogfish since sharks, in contrast to popular
opinion, are not relatives of ordinary fish and their method of procreation is totally
different. They do not bear thousands of young animals, but rather only two, four or perhaps
ten youngsters, with a small number of species bearing 20 young. In addition, pregnancy and
the time needed to reach sexual maturity is considerably longer. Unfortunately, the spiny
dogfish is probably the worst off in this respect. A female spiny dogfish may give birth to
about 20 pups, but these need 20 to 30 years to reach sexual maturity, and pregnancy itself
lasts about 22 months (see bibliography in this issue's Fact Sheet). The probability is
thus very high that an animal is caught even before it has had a chance to reproduce only
once. Yet this "one-time bearing of young" is biologically one of the most
important guarantees for species survival.
Much more serious is the effect of group behavior. In swarms, spiny dogfish swim mostly in
separate groups of males and females. A single catch may thus effectively eliminate all
sexually mature or all pregnant females. Today, it has already become very obvious that
spiny dogfish have not only gotten smaller in size but have also been reduced in numbers.
Man is literally scratching the bottom of the barrel. Up until April 1999 only a meager 57
tons of spiny dogfish were imported into Germany, 3% of previous average annual imports.
This is not dictated by lack of demand, which is best indicated by prices, considering that
high demand combined with a limited availability of raw materials will increase prices. In
Germany alone, the first quarter of 1999 was marked by 25% higher prices for frozen dogfish.
"...The rare quantity which reaches the market will soon turn into a rare and expensive
commodity...", comments J. Brümmer.
The hesitant reaction of U.S. authorities to these alarming signs is - as
always - perhaps too late. Current plans foresee a 50% reduction of catch quotas for spiny
dogfish in U.S. territorial waters, meaning from 20,000 to 10,000 tons annually. A further
step would totally forbid direct fishing. However, this directive from the Department of
Commerce will not go into effect before November 2000, besides being vehemently fought by
various interest groups. Only the future will reveal if the emergency brake was pulled in
Meanwhile, the future looks dismal for spiny dogfish.
Shark Info Shark Info is grateful to Jens Brümmer
from the fish smoking firm G.F. Wendt GmbH in
northern Germany for all his help in obtaining research data and spiny dogfish photos.
* Dr. Alexander J. Godknecht is a
biologist and President of the Shark Foundation. He is
also a member of the Shark Info editorial team and works in the Zurich University
Center for Computing Services.
May be published only by indicating the source: Shark Info / Dr. Alexander J. Godknecht