BOWERING: DISTRIBUTION OF WITCH FLOUNDER 



80 r 



i70^ 



60 



50 



40 



30 



20 



10- 



EARLIER 



MALE 



FEMALE 



LATER 



0^ — ' ' 1 1 1 1 1 1 1 1 1 I 1 



2 4 6 



e 10 



2J 

 3K 

 3L 



14 16 18 



^ 1 — ' — I 1 1 — -1 1 — I 1 1 I 



2 4 6 8 



AGE (YRS) 



10 12 14 16 18 20 22 24 26 



Figure 13. — A comparison among divisions for growth curves of male and female witch flounder from earlier and later time periods. 



area of Funk Island Deep in Div. 3K (Bowering 

 1985). In the late 1960's, however, heavy ex- 

 ploitation occurred in the Hawke Channel area of 

 Div. 2J with average annual catches of about 

 5,000 t as seen in Figure 2. Templeman (1966) 

 reported three research vessel catches of witch 

 flounder in Hawke Channel during April 1963 

 and 1964 of 2,300 kg, 1,400 kg, and 3,300 kg/hour 

 where these fish appeared to be concentrated. Re- 

 cent biomass levels of 2,500 t for this area as 

 previously mentioned are now quite low in com- 

 parison to the annual catch during the late 1960's 

 even if the catchability coefficient of the survey 

 gear is considerably <1. According to results pub- 

 lished in Bowering (1985) the age composition of 

 commercial catches from the management zone in 

 1976 were as old as 25 years compared to a 15-yr- 

 old maximum in 1984. In 1976, more than 40% of 

 the commercial catch was older than age 12 

 whereas in 1984 <5% of the catch was older than 

 age 12. It may be that concentrations during 

 prespawning have depleted these stocks, particu- 

 larly the older, mature fish. This may have con- 



tributed to the dramatic decline in landings since 

 the early 1970's. Unfortunately, estimates of 

 biomass for these areas prior to heavy exploita- 

 tion are not available for comparison. 



Witch flounder in this study were not caught 

 deeper than 900 m or at bottom temperatures 

 >7.0°C (higher temperatures were not encoun- 

 tered throughout the study area). Bowering 

 (1976), for the Newfoundland Region as a whole 

 during 1958-74, did not report catches of witch 

 flounder beyond a depth of 869 m, but they were 

 caught at bottom temperatures up to 10°C. Those 

 catches at high temperatures were due mainly to 

 the inclusion of catch data from the southern 

 Grand Bank area (Div. 3N and 30), where water 

 temperatures are highly influenced by the Gulf 

 Stream. Markle (1975), in studying young witch 

 flounder on the slope off Virginia, caught them 

 down to a depth of 1,408 m and a temperature of 

 11.3°C. He also found that they were caught in 

 significantly deeper and cooler water in Novem- 

 ber compared to June. Such a comparison was not 

 possible here. It should be pointed out, however, 



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