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Part III — Eighteenth Annual Report 



51 crabs, about 2 miles S. E. Of those set free in an E. by N. 

 direction, 32 were found to the north 'of the place of liberation, 

 that is to say they had moved along in about the same depth of water ; 

 14 were to the south of the same ; two which were set free one mile 

 from shore were got one mile further east ; while three, after intervals of 

 freedom of 24, 26, and 83 days, were found close to where they were put 

 away. The latter were set free — in August, two crabs, and in 

 October one crab, out beyond the twenty-fathom line. One crab, 

 No. 46, Table XI., was found to have travelled in 54 days to a point 

 8 miles from the place of liberation.* Of the crabs captured from 

 April to July, 14 had been set free at the mouth of the harbour, 

 and 13 offshore. Of the former, four were found near the harbour; 

 two of these had been liberated in December, the third in April, and 

 the fourth in June. Four which were taken at 1| miles N.W. (two 

 specimens), 2 miles west (one specimen), and 1| miles S.E. (one 

 specimen), had been set free in November. Two set free in January were 

 recaptured 1^ miles E. and f -mile E.S.E. of Dunbar respectively. Nine of 

 the crabs set free offshore were found in the summer months to the south 

 of the place where they were liberated. No. 6 (Table XI.) was, according 

 to the report of the fishermen, got 3 miles east by south, at which place a 

 depth of 20 fathoms is found. This was in April, at which time, I am 

 informed, no boat is fishing in water of that depth. 



It has several times happened that two crabs which were liberated 

 together were recaptured on the same day after intervals of 9 to 122 days, 

 and although in certain cases they have been found near one another, 

 it has oftener happened that the places of capture were at some distance 

 apart. One striking case is that of Nos. 11, 12, and 13, Table X, which 

 were captured on April 19th, after an interval of freedom of 165 clays. 

 Two were got near together ; the third was about 3 miles distant from 

 the others. All the lots of crabs, with one exception, show simply a 

 migration in one direction, which in the majority of cases is seaward, 

 in a few cases shoreward. The exception is a collection of crabs which 

 was set free at the mouth of the harbour in November, Nos. 6 to 14, Table 

 X. Of these, five were recaptured during December, January, and 

 February, at from 2 to 3| miles offshore. In April three were obtained 

 close inshore in 8 fathoms, and in May a fourth was found in 7 fathoms. 

 There is very little doubt but that the last four crabs had in November 

 gone off to deep water with the others, and had returned in April and 

 May to the shallows. With regard to the months in which they 

 take place, we are able to fix the migrations within certain limits. 

 When the take of crabs diminishes in June, the majority of the boats 

 bring their creels ashore and prepare for the summer herring fishing, or 

 begin line fishing. They return to the crab fishing in the middle of 

 September or beginning of the following month, according to the bad or 

 good result of the herring fishing. When they do so, they shoot their 

 creels right out in deep water. The few boats which continue fishing in 

 J uly and August do so close inshore, and the main portion of the catch 

 consists of females which have just hatched their eggs. In August a 

 considerable number of comparatively small soft crabs are also got 

 {see p. 106). Many of the large crabs which have come near the land in 

 April and May cast inshore, and move out to sea again. In order to 

 find what crabs were offshore in August, I arranged to have ten creels 

 shot 3 miles N.E. of Dunbar, at which place 18 fathoms were found. f 

 Ten crabs were obtained — viz., four large hard females 6^g to 6| inches 

 across, three of which had just hatched their eggs, four small males 4^ to 



* After going to press, a crab (No. 49, Table XI.) has been got in St. Andrews Bay ; 

 it has in seven months travelled across the Firth of Forth to a point 18 miles north of the 

 place where it was set free. 



f There is here a discrepancy between the distance from shore and the depth. 

 The distance or direction, judging from the chart, is piobatly at fault. 



