caused by jolting in transit and mov- 

 ing of the crate at transfer points. 

 Each compartment should have a 

 securely fastened water container 

 and sufficient nest material or straw 

 to prevent exposure, Muskrats are 

 especially susceptible to pneumonia 

 while in transit. Crates should be 

 labeled "Keep out of sun and away 

 from intense heat." Shipments 

 should be made during cool weather 

 whenever possible, as animals suffo- 

 cate easily during periods of intense 

 heat. 



Several ears of dried corn, a few 

 carrots, and a head of cabbage or 

 lettuce placed in each compartment 

 should be ample food for a muskrat 

 traveling a long distance. Success- 

 ful shipments have been made in 

 this manner from Maryland to Lou- 

 isiana, across the continent, and to 

 foreign countries. If muskrats are 

 moved by car or truck, care must 

 be taken to prevent their suffocation 

 or asphyxiation by exhaust fumes. 



RECOMMENDATIONS 



A high, sustained annual yield is 

 the primary objective of commer- 

 cial muskrat production. To attain 

 this objective close adherence to the 

 following basic principles of marsh 

 management is necessary : 



Maintain water levels at a depth 

 conducive to the best growth of 

 desirable muskrat foods, such as 

 the cattails and bulrushes. A di- 

 rect correlation exists between the 

 abundance and quality of food 

 present on a marsh and the number, 

 size, and weight of the muskrats 

 produced there. In general, both 

 the muskrats and their favorite 

 food plants require rather shallow 



water. Under northern conditions 

 the water must be deep enough to 

 prevent winter freeze-outs. An 

 ideal water condition is one in 

 which three-fourths of the marsh 

 is covered by water 18 inches or less 

 in depth, with numerous deeper 

 ponds, holes, and ditches inter- 

 spersed throughout the marsh. 

 Maintain stable water levels. Ex- 

 treme fluctuation in water levels is 

 very damaging to muskrats and 

 other wildlife, as well as to their 

 food plants. Water-control struc- 

 tures should be so designed that the 

 water levels can be raised or low- 

 ered as the need arises. 

 Use all sources of fresh water, 

 such as rainfall and runoff from 

 fields, woods, and drainage 

 ditches. Muskrats generally pre- 

 fer fresh to slightly saline water. 

 Prolonged droughts and high tem- 

 peratures increase salinity. In the 

 Gulf Coast region the most-produc- 

 tive muskrat areas are the brackish- 

 water, three-square marshes. 

 Storms and high tides often destroy 

 the favorite food plants of the 

 muskrat and exert a harmful effect 

 on the animals themselves. 

 Use controlled burning judi- 

 ciously. Although an important 

 factor in muskrat production, con- 

 trolled burning must be done only 

 when the water level in the marsh 

 is such that deep root burns will not 

 result to desirable food plants. At 

 least 3 inches of water should be 

 present over most of the area at 

 time of burning. Burning may be 

 used to remove the "rough"' and to 

 open up dense stands of undesirable 

 emergents, such as sawgrass (67a- 

 dium jcmiaicense) . 



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