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hard or too soft, they cannot burrow successfully. The 

 differences in the type of bottom found in our different 

 lakes probably explains why the nymphs are found in some 

 lakes and not in others, also why they may occur in one 

 part of a lake but not in other parts. A firm muck or 

 soft marl bottom is usually best suited to the needs 

 of the nymphs. They are not usually found in sand or 

 gravel, in hard marl, in very soft, flocculent muck, or 

 in peat bottoms. They are found in greater numbers 

 (provided that the bottom material is suitable) where 

 the bottom is quite bare and has only sparse vegetation. 

 In streams the nymphs will be found in eddies, back- 

 washes, and silt bars where the mud is of the right 

 consistency for successful burrowing. 



Successful digging of wigglers can be carried on 

 through the ice in water up to about 10 feet in depth. 

 Usually hand-operated, long-handled dip nets made of 

 1/8- to 1/4-inch mesh grit screen are used. A portion 

 of the bottom is dipped up through a hole previously 

 cut and is then washed or "puddled" by jiggling the 

 net up and down in the water. The bottom material 

 works through the screen mesh and exposes the wigglers 

 for hand picking. Other devices, such as rockers, are 

 used to wash larger quantities of the bottom material. 



Nymphs of many different sizes will be found in a 

 sample of mud from a bottom they are using. As only 

 the large ones are usable asbait, care should be taken 

 to return small nymphs to the water unharmed so that 

 the stock of May flies will be maintained. 



Proper care is necessary after the nymphs have 

 been collected ifthey are to be kept successfully over 

 a period of time. They must be kept in wwter having a 

 good supply ofoxygen at all times. As the nymphs seek 

 to avoid light and always try to dig into the bottom or 

 crawl under something, it is well to cover them with a 

 layer of burlap, under which moss or Chara has been 

 placed, to give them some protection. If they are 

 kept in an open tank, they will swim continually until 

 they are exhausted and will not survive long. 



Hellgrammite- 



The hellgrammite is the larval form of the dobson 

 fly. The larvae are found under rocks in the fast 

 water of streams, where they live for 3 years before 

 emerging as adults. They feed on May flies, stone 

 flies, and other aquatic insect larvae. The hellgram- 

 mite is easily recognized by the presence of slender. 



