174 SALMONID^ OF BRITAIN, 



Respecting the migrations of these fish in the Tweed some very interesting 

 figures were given by Russel (see p. 71 ants'), who showed the proportionate 

 nnm.ber that entered that river during the open months of the year. One-tenth 

 were taken in the first 3| months, or from the middle of February to the end of 

 May : and nine-tenths of the remainder during the 5| months extending from 

 June 1st to the middle of October. In June they suddenly augmented by 300 

 per cent., and in July stood at the highest figure : but the average weight of the 

 fish diminished, pointing to a large proportion being young. In October a great 

 increase again occurred not only in number but also in size, for now the breeding 

 fish commenced ascending.* 



In the Kyle of Tongue fine sea trout are found during April and May, while 

 in the Kyle of Durness some of moderate size, as from H lb. to 2.1b., commence to 

 show themselves the last week in April and during May. The smolt finnocks 

 abound in the Dee near Aberdeen in April, and improve in condition as the 

 season advances. In the Forth four distinct runs of sea trout have been recorded. 

 (1) Herlings iu January, from 6 oz. to 12 oz. (2) Sea trout in February, from 

 2 lb. to 5 lb. (3) Two differently coloured trout in May, from 1| lb. to 2 lb. weight, 

 one spotted all over, the other only below the lateral-line ; the flesh of one is pale 

 and of the other red. (4) Salmon-trout or bull trout, strong coarse fish from 

 4 lb. to 10 lb., and have been taken to 161b. and are first seen in July. While 

 Parnell observed that those which leave the sea about the end of July to enter 

 fresh water do so to deposit their spawn during the months of October, November, 

 and December. 



Passing on to the migrations of the southern and western sewin we find that 

 in the mackerel drift-nets employed from March until May in the Bristol Channel 

 single examples are frequently taken ; also at the mouths of rivers during summer 

 and autumn in hang or moored nets, and in fresh waters some are captured 

 throughout the year. But these migrations are subject to considerable variation, 

 thus of late years they have greatly increased in the Wye, while in 1860 they 

 were said to be rare there but numerous in the Usk and common in the rivers to 

 the west. The few that ascend the Severn, and which rarely exceed 1 lb. in 

 weight, do so mostly in July ; in the Usk the largest are about June, but they 

 become smaller in autumn ; an abnormally early one of f lb. weight and clean-run 

 was recorded in April, 1873. In the Ogmore, fish from 4 lb. to 5 lb. ascend in 

 April, those of about 2 lb. in May, and 1 lb. in August, while at Christmas some 

 enter the river in pairs, but they do not weigh above | lb. to J lb. In the 

 Towy and^the Teifif these fish are said to begin ascending in April, but June is 

 the month when they have been recorded as beginning to pass into rivers on the 

 Tef, Olwyd, Elwy, and Chester Dee, and during July into the Claddw. In the 

 month of June these fish would seem to become plentiful in Welsh rivers and 

 the Dee, being mostly so during July and August. In^ the Towy large ones 



should haye called sea trout but for their complete absence of silver colouring, the markings 

 pointed to them as bull trout. Those we are disposed to consider sea trout that have remained 

 long in fresh water, and lost their silver coat, as the Salmo fario acquires it in salt water." The 

 shoals^of sea trout he found to be most voracious, having "taken young herring in great'quantities 

 and squids also from their stomachs, and this may be the reason they keep towards the shore in 

 their progress riverwards." 



* Lord Home wrote an instructive paper on the sea trout of the Tweed to Yarrell, and in it 

 he observed that the bull trout {Salmo trutta) take the river (Tweed) at two seasons. The first 

 shoal comes up about the end of April and May. They are then small, weighing from 2 lb. to 

 4 lb. or 5 lb. The second, and by far the more numerous shoal, comes late in November. They 

 then come up in thousands and are not only in fine condition, but of a much larger size, weighing 

 from 6 lb. to 20 lb. They ascend the Tweed in scanty numbers during the spring and suimner 

 season, but are then in excellent condition. But the great ascending shoal of these fishes is that 

 which migrates to this and some other rivers for breeding purposes, and this occurs after the 

 commencement of the close season, or between the middle of October and end of November, 

 when, as observed Stoddart, they push up the river to the very sources of its tributaries and their 

 feeders. I have already remarked (p. 159) that Stoddart recognized sea trout from 1 lb. to 3 lb. 

 pushing up the Esk in summer : next herlings in July and August, succeeded by bills or bulls. 



t It has been lately asserted that in the Teifi or Tivy, in Cardigan Bay, sewin are now absent, 

 but present in either river on each side of it. 



