Table 3. — Species composition, catch rates, and average catches for effective fishing 

 effort in northern and southern Green Bay 



Southern Green Bay 



Northern Green Bay 



Species 



Species 

 composition 



Catch 

 rate per 

 1/2-hr. 

 effort 



Average 



1/2-hr. 



catch for 



effective 



effort 



Species 

 composition 



Catch 



rate per 



1/2 -hr. 



effort 



Average 



1/2-hr. 



catch for 



effective 



effort 



Pounds 



Alewife 



Smelt 



Suckers 



Carp 



Yellow perch 



Trout-perch 



Spottail shiners.. 

 Common whitef ish. . 



Sculpins 



Chubs 



Burbot 



Lake herring 



Others ; 



20,252 



3,0^9 



2,'i51 



2,622 



409 



297 



305 



22 



45 







37 



3 



42 



Total or average 29,534 100.0 



Percent •* 



68.6 

 10.3 

 8.3 

 8.9 

 1.4 

 1.0 

 1.0 

 0.1 

 0.2 



0.1 



T 



0.1 



Pounds 



209.6 



31.6 



25.4 



27.1 



4.2 



2.7 



3.2 



0.2 



0.5 



0.4 



T 



0.4 



Pounds 



234 



49 



50 



113 



9 



7 



10 



3 



6 



4 



1 



Pounds 



22,273 

 2,945 



480 

 85 

 30 

 46 

 18 



110 

 86 



103 

 12 

 37 

 15 



305.7 



306 



26,240 



Percent 



84.9 



11.2 



1.8 



0.3 



0.1 



Pounds 



294.1 

 38.9 

 6.3 

 1.1 

 0.4 

 0.6 

 0.2 

 1.5 

 1.1 

 1.4 

 0.2 

 0.5 

 0.2 



100.0 



346.5 



Pounds 



302 

 47 

 37 

 85 



6 



3 



4 



4 



7 



6 



3 



2 



r 2^ 



346 



•"■ T = Traop, less than 0.5 or 0.05. ^ Not calculated. 



TTf 1 



APRIL MAY JUNE 



AUGUST OCTOBER NOVEMBER 



Figure 2. — Availability of alewlves to bottom trawls In Green Bay by depth and month April 

 illustrate the catch rate of alewlves at 5-fathom depth intervals. 



December. Figures 



Alewives were lacking in all drags in April, 

 and catches were light in May. By June, ale- 

 wives were spawning, and the catch rate was 

 highest at 5 fathoms and declined sharply below 

 15 fathoms. The best catch rate in July was 

 obtained at 10 fathoms. During August, fish 

 could be taken at all depths, but the largest 

 concentrations were at 15 fathoms. In October 

 and November, alewives were scattered at all 

 depths, and large concentrations on the bottom 

 were difficult to find. During December, most 

 alewives were in the deeper waters of the bay-- 

 few were found in shallower depths. Alewives 

 apparently nnove out of Green Bay into deep 

 water in Lake Michigan in January and do not 

 return until May. 



Comnnercially significant catches (500 

 pounds or more per half hour) were made on 

 every cruise fronn June through December; 



however, it is »inlikely that alewives could be 

 harvested on a commercial scale from Green 

 Bay between January and May. Of the total 

 drags made in Green Bay, 18 percent con- 

 tained commercially significant quantities of 

 alewife. A summary of catches of alewives 

 by cruise and year is given in table 4. 



Smelt 



Smelt was the second most abundant species 

 in the trawl catch-- 10.7 percent by weight. 

 The smelt population appeared to be sizeable 

 enough to constitute an important species for 

 trawlers. Thirteen commercially significant 

 catches (150 pounds or more) were taken on 

 eight cruises. The overall catch rate and aver- 

 age catch for effective effort also indicate that 

 smelt would be an imp>ortant component in any 



