Drill traps were first employed successfully for several years in drill 

 control in Chincoteague Bay, Virginia (Stauber, 1938), and were later modified 

 and extensively utilized in Delaware Bay. New Jersey, by J. R. Nelson (1931) and 

 by Stauber (1943) J. R Nelson used young oysters from the Cape Shorg of Dela- 

 ware Bay for bait. He noticed that on beds of seed oysters traps baited with the 

 seed from the same bed gave moderately good results, but drills would not abandon 

 seed oysters on the bottom for the same size oysters in the traps as readily as they 

 deserted larger oysteis or vacant bottom for seed oysters. He ooncludes that the 

 drill trap is a practical, inexpensive, effective method of combating the drill. 



Galtsoff et al. (1937) in a continuation of the drill trap work in Delaware Bay 

 and its extension to other regions, undertook large scale experiments with a view 

 to investigating the practicability and improving the construction of the traps testing 

 the various baits, and learning the most efficient method of setting the lines of traps. 

 They describe and illustrate the method of the construction of the trap and state that 

 one to two yeai old oysters in clusters with mussels and barnacles, when these are 

 present on oysters, make the most serviceable bait. On grounds where drills are 

 not abundant and when a small number of traps are to be scattered over a large 

 aiea they recommend fastening traps individually or in pairs to stakes or from buoys . 

 Where infestations are high they recommend several methods of trap arrangement: 

 (a) a series of zigzag lines over the area to be trapped, which they state covers a 

 maximum territory and tends to attract drills from all directions; (b) placing a 

 single line of traps at one end of a ground and periodically moving it until the area 

 has been trapped; this is more economical but less efficient; (c) surrounding the 

 ground with tiaps and moving a long line of traps about within the area; the former 

 prevents reinfestation of a cleaned section; (d) the most successful procedure, 

 especially at Chincoteague, Virginia, involved the anchoring of one end of a long 

 line of traps in the center of a ground and shifting the position of the line about 15 

 degrees at intervals. They observed that where food is so abundant that drills 

 cannot be lured by bait : as along barnacle covered rocky shores of New England* 

 trapping by this method is impossible, but that it is highly efficient on drill in- 

 fested ground from which oysters have been harvested and consequently on which the 

 dull food supply has decreased 



The most prolonged and intensive study of drill control by the method of 

 drill trapping has been performed by Stauber in Delaware Bay. Early in his work 

 (Stauber & Lehmuth, 1937) he concluded that the drill trap is the most practical 

 and efficient device for the removal of drills and egg cases from plantings of young 

 oysters which it does not disturb, and presents the only attempt known at figuring 

 the cost of drill control by means of drill traps . He ar d Lehmuth in cooperation 

 with Captain Joseph Fowler of Bivalve, New Jersey, demonstrated the one outstand- 

 ing controlled example available of the practical benefits of drill trapping (T, C. 

 Nelson, 1939 40; pers. com; Stauber & Lehmuth, 1937). A 100 acre groui d 



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