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The Salt Lake Fairy Shrimp
By Harold L. Snow

Were you ever bitten by a shrimp while taking a dip in Great Salt Lake? Probably not, because the brine shrimp, or fairy shrimp, as it is commonly called, being known to the scientists as Artemia gracilis, is so small and insignificant, as well as being absolutely harmless, that it is usually not perceived by people who bathe in the salty water.

Very little attention has been paid the fairy shrimp in the past, and descriptions of the creature, as well as reference to it, are so scarce that it has become the general opinion of the public that Utah's salt sea is absolutely devoid of any form of animal life whatsoever. The absence of much literature on the subject is probably due to the fact that the fairy shrimp not only is of but little interest to those who attend the lake resorts to float on the surface of the dense salt water, but also because the creature at present is neither of any great significance as a benefit nor as a detriment to human society.

In certain parts of the lake not far from the shore one can catch hundreds of salt water animals in one double handful of the brine. They swim about in the water, first in one direction and then in the other, as if they were making a violent attempt to escape. But when observed from the surface of the lake they may be seen to move about in quite the same manner right in their native habitat.

Observed more closely, the fairy shrimp is seen to be from about one-third to one-half an inch in length, the male being somewhat larger than the female. Many of them are colored most beautifully. Some are of a light brown or almost a yellow color, while others are bright red, orange, green, brown or even a mixture of these colors. Eleven pairs of legs, co-ordinating in a wave-like movement along a horizontal plane, propel the shrimp through the brine with a gliding motion. The delicate and slender legs and body of the creature moving so gracefully through the water may be considered ample justification for man's christening it the fairy shrimp. A large pair of claspers resembling to some extent those of a crab or lobster, are seen in the male form, whereas the opposite sex has in their stead a small second pair of antennae. A small black spot right at the top of the head may be seen easily with a low power microscope. This is a centrally placed eye. In addition to this, the fairy shrimp has a pair of compound eyes. They are relatively large and easily arrest the attention of the naked eye.

Under the direction of Dr. Newton Miller, now professor of microscopic anatomy at the University of Utah, a special study of the brine shrimp was made by Albert C. Jensen in 1917, while taking out his master's degree in zoology. In describing the shrimp Mr. Jensen states that the stomach is situated in the head of the animal. Each of two lobes of the stomach receives a duct from the liver, which also lies in the head, even higher in its position than the stomach, he states. The brine shrimp's heart is in the form of a long tube extending nearly the entire length of the body. Blood is thought to enter the tubular heart through a series of valves in its sides, and to be pumped out at the two ends. Cases have been observed where the little round black eggs of the fairy shrimp laid by isolated females, have developed into mature animals without fertilization from the opposite sex, showing that the species may also reproduce parthenogenetically. However, in these cases most of the eggs developed into females.