17 



conditions in Campus creek due to freshets and other causes 

 render the stream very favorable for such work. 



To find these preferred habitats is difficult on account of the 

 great variation in distribution of fish noted at different times. 

 There are not only annual and seasonal fluctuations in num- 

 bers, but also daily and even hourly ones. Often they can be 

 correlated with changing environmental conditions but in many 

 cases, they can not be. An abundance of statistical data for 

 each type of habitat is needed, but this is not easy to obtain 

 even under the specially favorable conditions afforded by a 

 small, clear creek like the one under consideration. Unless 

 much precaution is taken in making direct observations, the 

 proportions of species and individuals seen will be very dif- 

 ferent from those that actually exist for wary fish, like horned 

 dace, hide, making the less shy fish seem to be the only ones 

 present. Collections will not always give accurate information, 

 for fish have different ways of responding to the presence 

 of a net. Some go at once into the mud and beneath stones, 

 and are easily missed, and the collection may contain only in- 

 dividuals that seek to escape by swimming. Often under very 

 favorable conditions for collecting have I failed to get a single 

 representative of a species which I knew, through observation, 

 was present in the place where collecting was done. To obtain 

 correct conclusions, therefore, concerning habitat preferences on 

 the part of a species of fish, it seems necessary to get an abun- 

 dance of data Dy every possible method during many seasons 

 and obtained at all times of the day and year. These data 

 for Campus creek are not yet at hand, so this paper will not 

 attempt to set forth habitat preferences, but will deal with some 

 of the more obvious environmental factors affecting the dis- 

 tribution of fish in Campus creek, which are : barriers, current, 

 fish food, water temperature, and shore vegetation. 



Barriers. Like most of the creeks about Charleston, there is a 

 long stretch of shoal just above the mouth of Campus creek. 

 This has a sandy bed with many ripple marks, and is usually 

 dry in late summer and early fall, while the part of the 

 stream above this area persists in its usual condition. This 



