Table 16.— A comparison of catch/effort data obtained directly from the sampling and interview data and from ratio estimates. 



1973 



1974 



1975 



1976 



Ratio Ratio Ratio Ratio 



Sampling estimate Sampling estimate Sampling estimate Sampling estimate 



and interview { + 1 SE) and interview (+ISE) and interview (+1SE) and interview (±1SE) 











Bloodworms 











Catch in no./ 



559 



536 + 36 



578 



630 ±20 



632 



662 ±26 



560 



567 ±35 



digger tide 



















Catch in no./ 



220 



210 + 12 



203 



219±5 



216 



233±6 



186 



193 ± 6 



digger hour 



















Catch in lb./ 



2.30 





3.27 



3.53±0.20 



4.21 



4.30±0.31 



3.34 



3.50±0.21 



digger tide 



















Catch in lb./ 



0.90 





1.15 



1.23±0.06 



1.44 



1 .51 ±0. 12 



1.11 



1.20±0.07 



digger hour 









Sandworms 











Catch in no./ 



1,107 



1,120 + 88 



954 



1.028 ±60 



1.120 



1.051+67 



1.318 



1.1S4 + 38 



digger tide 



















Catch in no./ 



526 



559 + 43 



490 



523 ±24 



576 



558 ±28 



626 



592 ±22 



digger hour 



















Catch in lb.. 



17.04 





12.37 



13.75±1.16 



14.26 



I4.16±0.93 



16.80 



15.40±0.92 



digger tide 



















Catch in lb./ 



8.10 





6.35 



6.96±0.52 



7.34 



7.65 ±0.37 



7.98 



7.73±0.52 



digger hour 



















.08 

 .07 

 .06 



p .05 



04 

 03 

 02 

 .01 



MAINE 



(A) 



LANDINGS STATEWIDE 

 o BLOODWORMS 



AVERAGE 







o 





« SANDWORMS 





o 









oo 







o 









o 



X 

 X 







O o 



,"" 



X * 



o 



o °°°oC°°°°° 

 ">r x x x x x XxxIX 



G 

 oo° X 



X * 













Table 17.— The price/worm recorded by month during the commercial sam- 

 pling program for bloodworms and sandworms (1973-76). 



1940 1945 1950 1955 1960 1965 1970 1975 1980 



.10 





(B) 













lOO 



09 





WISCASSET 



DEALER 











(1 



08 

















o 







o BLOODWORMS 













07 





» SANDWORMS 













3 



% .06 















it 



) 6 





£ 05 



Q. 











' 



\r 



5 





UJ 



5 04 















V 



.03 











< 



o 



>o 

 S 



X 



i'i 



02 





o 





r 



o 



r s 





01 



' o 



X 



X 





X 









1940 1945 1950 1955 1960 1965 1970 1975 1980 



Figure 13.— The price/worm paid to bloodworm and sand worm diggers. (A) 

 Price/worm information derived from Maine Landings estimates of landed 

 value and pounds landed (converted to numbers landed). (B) Price/worm 

 information recorded bv a Wiscasset marine worm dealer. 





1973 



1974 



1975 



1976 





Bloods 



Sands 



Bloods 



Sands 



Bloods 



Sands 



Bloods 



Sands 



April 



SO. 050 



$0,024 



$0,050 



$0,028 



$0,050 



$0,029 



$0,050 



$0,030 



May 



.050 



.028 



.050 



.030 



.050 



.029 



.050 



.029 



June 



.050 



.029 



.051 



.028 



.050 



.029 



.055 



.030 



July 



.050 



.028 



.050 



.029 



.050 



.028 



.060 



.032 



August 



.050 



.028 



.050 



.029 



.050 



.029 



.057 



.032 



Sept. 



.050 



.028 



.052 



.032 



.050 



.029 



.056 



.031 



sampling data forage. The method of Cassie (1950) was applied in 

 deriving estimates of the number of assumed year-class modes from 

 the length-frequency data presented in Figures 9 and 10, respec- 

 tively. The results of these analyses have been presented elsewhere 

 (Creaser"). However, year-class modes are not obvious in these 

 lumped length-frequency data, probably because worm growth 

 varies between flats, worm growth occurs throughout the 6-mo 

 commercial sampling period, and there is considerable overlap in 

 length at age. The reliability of the age estimates presented in 

 Creaser (footnote 37) are therefore questionable until the data can 

 be verified against other aging techniques. Estimates of natural and 

 fishing mortality, growth, and yield in weight per recruit are not 

 included in this manuscript because of the problems inherent in the 

 age analysis of the length-frequency data from which these esti- 

 mates are derived. 



Yield-Effort Curves 



Fisheries can be managed through size restrictions, a reduction in 

 fishing (digging) mortality, or a combination of both methods. Suf- 

 ficient data presently exist to explore two means of limiting digging 

 mortality: limited entry and quotas. 



'Creaser. E. P.. Jr. 1978. Marine worm research. Completion report Maine Dep. 

 Mar. Resour.. Augusta. 226 p. 



46 



