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Show 1870.] INTRODUCTION OF SALMON INTO TASMANIA. 25 and estimated those he had been unable to count of the Salmon-fry at about 1500. In July, 1866, all the remaining parr, seventy-seven in number, of the shipment per ' Norfolk' were liberated; and every fish showed distinctly the approaching change to the Smolt form. On the 3rd of July ova and milt were taken from the first pair of Trout (S. fario) which ever arrived at maturity in Australia. By the 7th of August fourteen females had been stripped, yielding about 4050 ova. Shortly afterwards five pairs of Trout (ten of the thirty-eight fish turned into the Plenty) were observed constructing rids in that river. The Trout in the river were considerably larger than the largest in the clearing-pond, though several of the latter weighed more than a pound each. During July and August, 1866, a large number of deaths took place amongst the fry from the last shipment of ova ; the total loss being 470 Salmon-fry and 65 Salmon-trout fry. On the 30th of September, 1866, the Trout-ova taken from the fish in the clearing-pond commenced hatching; but a large number of eggs proved barren. During August the fry, both of Salmon and Salmon-trout, ex ' Lincolnshire,' were permitted to escape into the large pond and the rill attached, with the exception of a few pairs of Salmon-trout, retained in the pond and rill purposely constructed for them in the hope that spawn might be obtained without the previous migration to the sea. From the end of September the operations at the ponds were simply repetitions of what had taken place with regard to the first experiment, some variety occurring through the addition of the Salmon-trout and the occasional capture of large Trout in the Plenty. One was taken on the 13th of January, 1867, 17_ inches in length and weighing three pounds. Although the bulk of the Smolts of the first shipment left the river in October and November, 1865, and should, according to most authorities, have returned as Grilse in the February following, no report reached the Commissioners of any thing resembling Grilse having been seen. Mr. Ramsbottom always maintained that the Smolts did not return as Grilse in three months, but that they would return in one year and three months; and so convinced was he of the correctness of this view, that he made no systematic watch for the fish in 1866. The mere fact that no report of the fish being seen reached the Commissioners by no means proves that they did not return in February 1866 ; for it must be remembered that, under the most favourable view of the case, not more than 1000 or 1500 Smolts can have left the Plenty, and were thenceforth distributed over a river but little smaller than the Severn in England, and into which numbers of large tributaries, admirably suited for Salmon, emptied themselves. In February and March 1867 fifteen persons, including Mr. Ramsbottom, reported that they had seen Salmon or Grilse in the fresh waters of the river Derwent. Several of these witnesses were gentlemen of high respectability ; and it is impossible to conceive that |
