CHAPTER III 



METHODS OF COLLECTING AND 

 PHOTOGRAPHING 



By JACOB REIGHARD 



Professor of Zoology in the University of Michigan; Formerly Director of the Lake Laboratory of the 

 U. S. Bureau of Fisheries, at Pul-in-Bay, Ohio 



Methods of Collecting 



I. Vertebrates 



I. Fish must be collected under the state laws which usually 

 forbid the use in inland waters of any apparatus except hook and 

 Hne or dip or lift nets held in the hand. In most states licenses to 

 use nets for scientific purposes may be obtained either from the 

 state fish commission or from the game and fish warden. 



(a) Seines are long nets with a weighted lead line attached to 

 the lower edge and a cork Hne attached to the upper edge so that 

 the nets remain upright in the water. When the net is so stretched 

 that it forms rectangular meshes "square mesh" is the length in 

 inches of one side of a single square. For use in brooks or for col- 

 lecting small shore fishes, seines twelve or twenty-four feet long 

 and four or five feet in depth are suitable. The former should 

 be of one-quarter inch square mesh, while the latter may be of 

 one-half inch square mesh. 



For larger fish, seines of fifty and one hundred feet in length, five 

 to nine feet deep and of inch mesh should be used, but larger 

 seines are not easily handled by two persons. The longer seines 

 should be of the twine ordinarily used for such purposes and 

 knotted at every crossing. For the shorter lengths the excellent 

 and cheaper ''common-sense" minnow seines which are woven to 

 resemble coarse burlap may be used. Very serviceable seines 

 may be made of a good quality of heavy bobbinet which may 

 be had of dealers in dry goods. All seines are much more 

 efficient if provided with a bag at the center, as is the Baird col- 



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