FISHERY BULLETIN: VOL. 74, NO. 2 



digestion until only unidentifiable material re- 

 mained in stomachs collected just before and after 

 sunset. Fish with full stomachs and undigested 

 contents were first collected at 2200 and 2400 h. 

 These were probably returning to scallops as they 

 became satiated. All fish do not leave the scallops 

 at sunset (Figure 7). Some may remain if they 

 still have food in their stomachs. Those fish 

 examined around 2000 h did not have completely 

 empty stomachs (Figure 8). None of the fish 

 examined at 0200 and 0400 h had empty 

 stomachs. 



The number of L. inquilinus occupying sea 

 scallops probably decreases through the fall and 

 early winter. During September 1968, 43 collec- 

 tions near Hudson Canyon (Figure 6), which 

 overlapped the collecting area in August 1969 

 (Figure 6), yielded fewer fish per scallop (Table 3) 

 than in August. These differences could be due to 

 relative year-class strength or may reflect an ac- 

 tual change in the number of fish occupying scal- 

 lops later in the year. Mortality of L. inquilinus 

 owing to predation or a breakdown in the associa- 

 tion as the fish grow larger could explain a de- 

 crease of this magnitude. Small numbers of sea 

 scallops collected during the fall and early winter 

 of several years did not yield as many L. in- 

 quilinus as were collected earlier in the year. 



Size of individual sea scallops may be a factor 

 in their selection by fish. In one instance, a 

 60-mm scallop contained a 21-mm TL fish, but it 

 is the larger scallops which contain the largest 

 number of fish (Figure 9). 



Table 3. — Abundance and average total length of Liparis in- 

 quilinus in sea scallops from August 1969 and September 1968. 



Collecting 

 dates 



Number of 

 scallops 

 examined 



Mean number 



of fish 



per scallop 



Maximum Average 



number in TL of fisfi 

 single scallop (mm) 



4-5 Aug. 1969 

 14-17 Sept. 1968 



841 

 717 



4.2 

 1.7 



32 

 18 



21 

 26.1 



.. . • : }... 



. . :. : I . :. .. . 1...1. 

 . .■•• J- 



. .. . !.:.». .1! t .. . 



. .. \:' .:■..!,• , '.=!i*i:-'.l .• . • 



>:•■• '•• -X- :•= • + . 



. I ij.i ji..' I..:: I. 1.; . 



90 100 110 120 130 



SC4L1.0P HEIGHT (mm) 



Figure 9. — Plot of mean number of fish per scallop versus 

 scallop height (mm) from daytime collections from Albatross 

 rV cruise 69-8. 



7n 



6- 



o 



< 

 o 



CO 



or 



UJ 

 Q. 



I 



a: 



Hi 

 CD 



4 - 



3- 



1!" 



STA 1-149 

 N. a N.E. 

 GEORGES BANK 



STA 150-206 

 SOUTHERN 

 GEORGES 



STA 227-314 



NEAR 

 HUDSON CANYON 



Geographic Variation in Abundance 

 of Fish in Scallops 



Figure 10. — Plot of mean number of fish per scallop at differ- 

 ent localities from collections of 5-17 September 1968. 



The abundance of fish in scallops varies with 

 geographic location (Figure 10). On Albatross IV 

 cruise 68-14, 155 10-min scallop dredge tows were 

 made as part of a sea scallop survey on Georges 

 Bank and in the Mid- Atlantic Bight near Hudson 

 Canyon (Figure 6). From these, 2,274 L. in- 

 quilinus were collected fi"om 1,228 of the 5,905 

 sea scallops examined. The mean number of fish 

 per scallop (Figure 10) and the mean number of 



fish per station (Table 4) were highest north of 

 Hudson Canyon, lowest on the north and north- 

 west edges of Georges Bank, and intermediate on 

 southern Georges Bank. Although the greatest 

 abundance of fish in sea scallops occurred near 

 Hudson Canyon, where the average depth and 

 bottom temperature were lowest (Table 4), these 

 parameters did not seem to be related to abun- 

 dance in this area (Figures 11, 12). The average 



418 



