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JOURNAL OF MAMMALOGY 
canals. The pallid muskrat is a typical burrow-dweller. This animal 
is reported to build houses in certain cat-tail swamps near Salton Sea, 
but none of the trappers interviewed, or the writer, has ever been able 
to locate such a muskrat house. Jt is believed that the mildness of 
the winter climate makes houses unnecessary to the animal. Some 
damage is certainly done by muskrats burrowing into canal banks, 
but this is comparatively slight considering the total numbers that 
live in the canals. The writer dug out a number of burrows in canal 
banks and found that much of the damage attributed to the muskrat 
was really being done by the gopher. None of the muskrat burrows 
dug out, was found to extend over half-way through the embank- 
ment. Normally these rodents begin from one-half to three feet 
below the water line and burrow straight into the bank. Where the 
bank is high close to the water^s edge, the burrows were found to extend 
in for two or three feet and then turn abruptly upwards, ending in a 
nest cavity which is usually placed just above the highest high-water 
mark. If the bank is low, the rats sometimes burrow over the crest of 
the bank to reach a protecting clump of brush under which the nest 
is built. Where two canals are close together, muskrats sometimes 
burrow from one to the other. They sometimes cause breaks by bur- 
rowing around wooden head gates, through which they have been 
known to gnaw small holes. On the whole, damage to headgates 
and canal banks, due solely to muskrats, was not found to be as 
extensive as reported. 
Prime muskrat pelts, even if from the warm Imperial Valley, have a 
decided value. During the trapping season of 1918-19, W. W. Morri- 
son of Holtville caught 1124 muskrats which sold for $1,108.00, an 
average of nearly one dollar a pelt. The highest price received for 
one pelt during that season was two dollars. In 1919-20 Morrison 
caught 1738 muskrats which sold for $2,805.00, an average of $1.61 
per pelt. Out of this lot of 1738 skins, five extra large pelts sold for 
five dollars each and 82, number 1 large, sold for four dollars each. 
At Eastside Heading, below the boundary, M. C. Kissinger secured 
333 muskrats in 1919-20. These skins were mostly small, yet they 
sold for $456.25, an average of $1.34 per skin. Allowing a value of 
$1.25 a pelt, which is a very low estimate, we find that the 25,000 musk- 
rats caught in the Imperial Valley in 1919-20 yielded the trappers 
an income of over $31,000.00. This record places the muskrat first 
as to number taken, and second in aggregate value, among the fur 
bearers of California for that year. 
