, \ ' '... This paper not to be cited without prior reference to the author International Council for the Exploration of the Sea C.M. 1965 Herring Committee No. 118 The Herring Races in the Skagerak in Recent fears by Aage J.C. Jensen A very large fishery for adult herring took place in October-November 1964 at the limit between Skagerak and the North Sea, sometimes also to the north of Hirtshals and. It has been proposed that this was due to an immigration of the Norwegian winter-spawning herring in the course of changing their spawning places as predicted by Devold. Samples of the catches were investigated for length, maturity and race, and the resulto of the racial investigations from these sampies und of a sampie from E. of L~S0 in 1964 and previous sampies from the same areas are shown in table 1 and fig. 1. It is seen that the herring in the autumn fishery of 1964 belonged to races which have been fished here also in the previous years, but actually their relative frequency differed from the average for some more years. Such averages are shown in table 2. Table 2. Percentage composition of catches from the Skagerak. 1940-49 1950-54 1955-60 1961-64 North Sea autumn spawners 70 55 45 58 Kobbergrund'miltumn' sp. + 2 5 9 Kattegat coast autumn sp. 2 8 10 7 Atlanto-Scandian incl. Kattegat winter sp. 25 25 35 26 Kattegat coast spring ap. 3 10 5 o In this tab1e the North Sea deep water herring are included in the other North Sea autumn spawncrs. In earlicr publications e.g. those where basis diagrams are shown I had not shown them as aseparate group because I had doubted about the racia1 characters as found by A.C. Johansen,
G a. -2- who had very few examinatiens cf fully mature fish at his disposal when he compiled the dharacters of this race(in: On the summer and autumn spawning herrings cf the North Sea. Medd. f. Komm. f. Havunders. Sero Fiskeri. Their characters are very near to these of the Downs herring, and when we have a sample of not fully mature herring it may be difficult to attribute them to a group becatise mixtures with herring of other races often disturb the clear picture. Therefore in thc analyses of young herring from the Skagerak I have sometimes named them Downs herring. In the course of years so many racial analyses of herring which are with certainty deep water autumn herring have been carried out that they show that this race differs from the Downs herring in the low K and VP. 2 In the October-November sampies from the Skagerak in 1964 the North Sea deep water herring constituted about 20 %and other North Sea autumn spawners about 70 %of the total number, against about 10 %of the Kattegat winter herring which are cf the At1anto-Scandian tribe. SampIes from the north-eastern North Sea are compi1ed in table 2. Two third of the sampies from the Danish fishery in the region Bergen - west of Stavanger - Wiking bank - Cape Stat consisted mostly of North Sea autumn spawners, all of them deep water herring, but for one sampie from west of Stavanger from July 1963, which were Fladen ground.. herring. Nearly a third of the herring from these fisheries were Norwegian winter spawners (the Atlanto-Scandian tribe). A sample of this race from north of Bergen from February 1958 was most courteously provided from the Norwegian Institute for Sea and Fishery Research,Bergen, and it is shown in the table. Off Egersund to southwest of Stavanger a large Danish and Swedish fishery has been carried out from November to February. It has mostly been based on the North Sea autumn spawners, about equal quantities of deep water and Fladen ground herring but in 2 of 10 sampies apart of the catch belonged to the Atlanto-Scandian tribe. The North Sea deep water autumn spawners seem to have becomo more numerous in thc catohes from the north-eastern North Sea during recent years.
. ~'.., -3- C.M. 1965 Herring Committee No 118 Fig. 1. Racia1 charactets of herring fished for human consumption in the Skagerak and northern Kattegat in October-November 1964 (large dots), and in September-December 1960-63 (small dots},in January-March 1961-64 (+) and in Aprii-August 1960-63 (x), comp. tab1e 1: The basisdiagrams for the North Sea, Skagerak, Kattegat and Be1ts are shown. Characters ca1culated from 30-60 herring are in encirc1ets.
.1... 15.oj-----------l-------!.9.8.7.6.3.2 Belts autumn.1 -.9.8 55.6.7.8.9 56.0.1.2.3.4.5.6.7.8.9 57.0.1.2 57.0.1.2.7 e. 6 Belts autumn Kattegat autumn :t <:) 24
C.M. 1965 Tab1e 2. Racia1 Characters of Herring Fished for Human Consumption in the No. 118 Skagerak and Northern Kattegat. Mt;:Midwater trawl, T: Bottom trawl, Ps: Purse seine, P: Pound nett In second co 1umn Hi: Hirtshals, Ha: Hanstholm, in 12th co1umn Katt. co. a.: Kattegat coastal autumn, Katt. W. Kattegat winter spawning herring, Deep W. North Sea deep water herring. Year Loca1ity Depth Gear Length Maturity date m cm 1960 5.10 N.of the 141 Mt 18-27 Scaw 29.10 E.of LalS'" 30.11 N.ofLres0 72 35 T 20-27 1-11 VII-VIII T 20-28 1-11 VS Nt' VP Race 1-11 56.89 151 24.36 14.31 144 Atl.Sc. 56.67 55.96 56.37 46 24.2~ 14.48 46 Mixture 51 24.67 14.33 51 Katt.co.a. 119 24.40 14.32 117 Kobbergr. 1961 2~1. At the Kobbergr. 20.2... NW Scaw 23.3. + off Hi. 68 14.3. At Grebbestad 50 100 7.8. NVl Hirts- 113 hals 19.9. NNE of 185 24.9. At the 76 Kobberg:c 16.10 E of LalS0? 24.10 E of Lres0./? T 23-34 VI-VIII T 17-27 1-11 23-28 VII-VIII P 22-3? IV-VII T T T T 18-28 22-29 22-29 1-111 IV-VI IV-VI 23-32 VII-VIII 23-32 IV-VIII 57.01 56.78 56.24 57.09 56.89 56.33 56.17 56.29 56.24 48 24.64 14.77 48 At1.Sc.? 316 24.21 14.39 295 Katt.W. 38 24.55 14.55 38 Kobbergr. 193 24.50 14.10 192 Bohuslän T 17-27 1-(111) 56.71 45 24.11 14.12 43 Katt.W.? 186 24.19 14.56 179 Katt.W. 39 24.38 14 42 38 Kobbergr.? 154 24.85 14.47 153 Katt.co.a. 233 24.77 14.44 232 Kobbergr. 210 24.77 14.42 201 Kobbergr. 1962 e10 N of LreS0 8.10 N of Lres0 22.10 NNW of 23 24 174 T 25-33 T 20-32 Mt 17-33 IV-VIII IV-VII 1-11 56.35 56.13 56.61 71 24.74 14.35 71 Kobbergr. 190 24.42 13.30 183 Katt.co.a. 227 24.13 14.32 222 Mixture :1.963 17.1. NxE of 122 17.1. N of 113 22.1. N of c.125 24.4~ E of LreS0 38 2.9. NxW of 240 18.9. At the Kobbergr. 71 29.10 NNW of 146 Mt 19-25 20-32 T 20-25 I li-vii 1-(11) T 20-25 1-(11) T 18-32 Mt 23-30 1-11 1-111 56.40 56.52 56.49 139 23.78 14.45 139 83 23.95 14.36 81 Fladen Fladen 170 23.88 14.37 175 Fladen 56.60 -'58 24.02 14.47 58 Gut? 56.27 147 24.33 14.31 127 Kobbergr.? 56.91 117 24.07 14.32 117 At1.Sc. Mt 23-27 IV-V 56.24 102 24.51 14.42 102 Kobbergr. Mt 24-30 I-V 56.4481 24.20 14.48 81 Mixture 24-31 VII-VIII 56.25 110 24.43 14.39 109 Kobbergr.
-2- C,M. 1965 No. 118 Year Loca1ity Depth Gear Length Maturity VS No VP K 2 No Race date m cm 1964 13.1. NNW of 210 Hi. Mt 17-31 1-11 56.36 192 23.70 14.38 191 Fladen 14 1. NW of 100 Mt 20-29 1-11 56 42 184 23 77 14.63 180 Fladen the Seaw 16.10 E of LalS'" 30 T 24...33 V-VIII 56.28 499 24.57 14.41 497 Kobbergr. 20.11 N of Ha. 130 Mt 23-30 11 56.49 150 23.58 14.41 150 Fladen 26-32 III-IV 56.88 56 24.23 14.00 55 Atl. Sc. 1.1O-N of Ha. 134- l1t 20-32 V-VIII 56.65 66 23.80 14.26 65 Deep w. 20.11 330 16.10 N of Ha. 134- Mt 22-31 (1)-11 56.47 238 23.72 14.34 236 Fladen 330 23-32 111 56.90 58 24.12 13.88 58 Atl.sc.
C.M. 1965 No. 118 Tab1e 3. Racia1 Characters of Herring Fished for Human Consumption in the North-Eastern North Sea 1951-65. Abbreviations as in table 2. - J:ear Loca1ity Depth Gear Length Maturity VS No VP K 2 No Race date m cm 1951 1.3. At Krake- 260 Mt 26-37 li-viii 57.27 139 24.43 14.23 139 Atl.Sc. nes(s of Cape Stat) 1953 13.2. S of Kra.- 94- Mt 22-37 I-V 57 19 149 24.30 14.09 149 Atl.Sc. kenes 300 ~_5 30 4 Off Eger... 120 T 18-24 1-111 56.50 148 23.91 14.44 117 Fladen sund 24-30 VII-VIII 56.53 139 24.06 14.78 135 Dogger 18.2. Off Mar- 282 Mt 21-38 I-VIII 57.12 269 24.36 13.94 167 Atl.Sc. stein(sw) Bergen) 1958 28.2. N of Bel'- gen 125 Ps 29-37 IV-VIII 57 01 179 24 34 14.01 172 Atl.Sc. 14 4. SW of 130 Mt 23-31 1-111 56.81 75 23.87 14.30 75 Mix-t.".1.re Stavanger..~....... 25-32 VI-VIII 56.65 83 23.83 14.26 81 Deep w 12.11 Off Ege:r-- 200 Mt 21-30 1-111 56.61 155 23.59 14.66 153 Deep w. sund 27-34 IV-V 56 93 60 24.32 13.92 60 Atl.Sc. 1959 ~e E of "'i- 160 Mt 21-33 I-VIII 56.66 163 23.85 14.31 133 Deep w. king Bk. :1.2.11 Off Ege:r-- 159 Mt 21-32 I-VIII 56.62 251 23.54 14.35 64 Deep w. sund 1960 12.2. W of Sta- 200 Mt 20-28 I-VIII 56 54 178 23.56 14.33 173 Fladen vanger 18.11 SW of 151 Mt 20-30 I-VIII 56.58 177 23.62 14.34 159 Fladen or Stavanger Deep w. 29.11 \v of Sta- 235 Mt 22-30 (1)-11 56.68 94 23 72 14.05 94 Deep w. vanger III-V 56.88 25 24.28 13.68 25 VII-VIII 56.51 117 23.45 14.63 117 Fladen 1961 ~3.2. W of Sta- 260 Mt 21-30 1-111 56.57 127 23.63 14.26 124 Deep w. vanger 23-31 VII-VIII 56 51 105 2}.54 14.61 104 Fladen 2 4 SV! of Wi- 250 Mt 24-30 11 56.53 99 23 58 14.28 98 Deep w. or king Bk. Fladen 25-31 VII-VIII 56.77 77 23.67 14.53 77 Deep w.
...., J -2- C.M. 1965 No. 118 Year Locality Depth Gear Length Maturity VS No VP K 2 No Race date m cm 1963 17.l. Off Eger- 282 tu 19-31 1-111 56.62 235 2~.83 14.33 235 Deep w. sund 26-32 VIII:56.58 43 23.84 14.47 43 Deep w.or F1ad. 20.3. W of Sta- 192 Mt 20-26 1-11 56.49 273 23.72 14.40 271 Mixture vanger 24-31 VII-VIII 56.58 117 23.67 14.32 117 Deep w. or Fladen 22 7 SW of 245 Mt 24-31 I-V 56.44 200 23 57 14.55 152 Fladen e Stavanger 29.7. SW of 245 Mt 24-31 I-II 56.98 105 24.26 13.97 111 Atl.Sc. Stavanger III-V 56.45 95 24.16 14.26 88 Mixture 1964 8.3. WNW of Bergen 200 T 27-33 III-VII 56.99 96 24.34 14.04 95 Atl.Sc. 1965 6.5. SE of Wi- 222 Pt 23-31 li-li! 56.52 48 23.73 14.37 48 Fladen king Bk. 25-32 VII-VIII 56.76 37 23.86 14.28 37 Mixture