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Part III. — Twenty-seventh Annual Report 



The empty stomach was sometimes shrunken, and in a dry condition. 

 This was found in full herrings. It was occasionally squeezed flat between 

 the two large roes or milts. This indicated a more or less inactive con- 

 dition of the stomach, but it did not mean that the fish could not feed if it 

 wished. Full herrings very often have very little food in the stomach, 

 but they feed. In some cases food was found in the anterior part of the 

 stomach, while the lower end, beyond the pylorus, was pressed flat between 

 the two large reproductive organs. In one lot of fish, although the repro- 

 ductive organs were very large, the stomachs were fully distended with food. 



Food was found in the stomachs of the Summer Fulls of the East 

 Coast. The Winter Fulls of the Clyde usually had a large quantity of 

 food (schizopods and copepods) in their stomachs. The ripe herrings got 

 on Ballantrae Bank in February had empty stomachs. In March the 

 stomachs of eight ripe herrings from the same locality were examined. 

 One contained food, the other seven were empty. Sim found full herrings 

 with their stomachs crammed with Crustacea. Matthews also drew atten- 

 tion to the food in the stomachs of ripe herrings. The migration of the 

 herrings from Loch Fyne at the end of the year is probably due to the 

 necessity to find food. 



When the stomach of the herring is large and filled with food it is gene- 

 rally referred to by the fishermen as a " bag " or " gut-poke." The bag may 

 be of different colours, according to the nature of the food which fills it. 

 Thus, a red bag is filled with copepods, a purple bag with the larvae of 

 decapod Crustacea, a brown bag with Limacina and copepods, a blue bag 

 with Crustacea and young fishes (sand-eels). The gastric juice that is 

 present in the stomach containing food very soon attacks the wall of the 

 abdomen, and causes the splitting of the belly of the herring. 



Milroy stated that " it is possible that for a short time (a month 

 perhaps) after spawning the herring does not take food." I do not think 

 that this is likely to be the case. The herrings seem to feed eagerly 

 immediately after spawning. During February, March, and April, in the 

 samples from the Clyde where the condition of the stomach in the winter 

 spents was noted, food was found in the majority. Watt stated that the 

 spent herrings, instead of crowding together as they did before spawning, 

 begin to look after their prey with great keenness, and to spread them- 

 selves over a wide area, of sea, most probably without regard to locality or 

 special order in their movements. 



The search for food is given by Sim and Watt as the reason for the 

 migration shorewards of the mattie herrings in the summer. Sim also 

 says that the food may be blown by the wind, and the herrings follow it. 

 According to Brook, the floating masses of copepods are easily affected by 

 the wind and tide, and according to the direction of the wind the copepods 

 (and therefore the herrings) may, in Loch Fyne, be expected in certain 

 quarters. This is not an infallible guide, but it serves as a basis to work on. 



LITERATURE. 



Brook. — "Report on the Herring Fishing of Loch Fyne and the adjacent districts 

 during 1885." Fourth Annual Report of the Fishery Board for Scotland for 

 1885, p. 48. 1886. 



Brook and Calderwood. — "Report on the Food of the Herring." Fourth Annual 



Report of the Fishery Board for Scotland for 1885, p. 102. 1886. 

 Cunningham.—" Marketable Marine Fishes." London, 1896. 



Dahl, Knut. — "Age and Growth of Fishes : the Herring and Salmon." Review of 

 the Norwegian Fishery and Marine Investigations, 1900-1908. Report on the 

 Norwegian Fishery and Marine Investigations, Vol. II., 1909, No. 1. 



Ewart. — " Natural History of the Herring." Second Annual Report of the Fishery 

 Board for Scotland for 1883, p. 61. 1884. 



Fulton. — " The Rate of Growth of Fishes." Twenty-second Annual Report of the 

 Fishery Board jor Scotland for 1903. Pt. III., p. 141. 1904. 



Fulton. — "On the Growth and Age of the Herring (Clupea harengus)." Twenty- 

 fourth Annual Report of the Fishery Board fo Scotland for 1905. Pt. III., 

 p. 293. 1906. 



