QUINNAT SALMON MARKING EXPERIMENT ATLANTIC SPECIES

Evening Post, Volume CXII, Issue 82, 3 October 1931, Page 5

QUINNAT SALMON MARKING EXPERIMENT ATLANTIC SPECIES

"An understanding of the migrations of salmon is a question of more than scientific interest," stated Mr. A. E. Heffor*; Chief Inspector of Fisheries, to-day. : "It is a matter of considerable practical; importance. The present distribution of quinnat salmon in varioui New Zealand riven has come* about mainly as ft result of natural migration. While little or n» result has accrued from, attempt* at the artificial stocking of such rivers as the Hokitika (West Coast of South Island), and Wairau (North-east coast of South. Jsland) all the larger rivers of Canterbury are now invaded by annual runs of these fish.from the sea, and their waters are stocked by the progeny produced by natural, spawning. The. ancestors:of all these Canterbury quinnat were undoubtedly, the stock which was originaly liberated in the Waitaki River system. It fc * matter of practical interest to know to what -.*s• tent this dispersal of quinnat bred in tha Waitaki system to other riverayi* ■till taking place. With a view to getting some information on this, point we have marked a number of parr reared in a pond at the Hakataramea-Hatchery. The-fish were marked by cutting off the adipose and one of the ventral fins, this method of marking having given satisfactory"' results in the case of guinnat marked at the sain* stage of growth in certain California* "In'i93o smolts to the number «f 3BU were marked by removal" of the adipose and right ventral fins. In 1931. A total of 6042 young fish hag been marked by removal of the -left ventral and adipose fins. The marked fish were liberated in . the Hakataramea River whence they would find their,way to the sea via the Waitaki. The earliest, returns from the 1930 experiment may be expected in the fishing fes* son of 1932. "The collection of scales from quinnat salmon for the determination of age is being continued. Casually collected •amples have been forwarded by anglers but more comprehensive collections are being -made of scale samples from the fish trapped fbr hatchery purposes. There is no one arail- ■ able on the staff of the Department to carry on a comprehensive study of *'this material, but there is & possibility that Mr. Parrott, biologist to the Fresh Water Fishery Research Committee of the Acclimatisation Societies Association, may be able to make the necessary examination for a scientific report. ' ~' "On 20th November, 1928, forty thousand Atlantic salmon fry, hatched out in .the Christchurcb hatchery of the North Canterbury Acclimatisation .Society from 'ova supplies by the Department from T« Allan, were liberated in two streams flowing into Lake Coleridge. This.is a lake abont;B miles long and two miles wide, ntnated among the hills in the back coimtryjfbWit 60 or 70 miles distant by road from ChrwJchurch. This Uke formerly had ■ajputflow into the, Harper River, a tributary of the Rakaia River. Since the. waters of the lake were "harnessed" for ihe purpose of the Lake Coleridge hydwtfeetnc Scheme (started in 1916), this Bma : River outflow has been cut off and the * only outlet is by way of the penstocks, to the ppwefc-station turbines. There is therefore no possible access to the lake for any fish returning via the, Rakaia: R*ter from the sea. . , . •';■.' .''.'•'• ','• 'It was on this account that the supply of' ova above mentioned wa» granted'_to the North. Canterbury AcclimatuatKm Society in 1930, in order that an indubitable stock of "land-locked" lake-fed Atlantic salmon might be produced. So far as this Department was concerned, the main object was to enable light to be throws on the,natural history of lake^iwelhag salmon in order to assist jmr iindawtandißg of the salmon of Lake Te Anan. All the evidence available got* to show that, itt spite of the fact that there w eaty access to the sea by way of the Waiau River, the majority of the salmon taken m Lake Te Aha'uand- ite tributaries bava never been to salt water, but have .r«aauw?d and fed in the lake up to the time of attaining maturity. ■ ~ i ■ V "Attempts to-interpret the btotory of Te Anaii salmon by examination wJajjJC-v scales have not thrown any very ««"*• light on the subject, though it M quite p^sible thata detailed *fyM**™& tative samples of scales taken from•»» caught in the tideway and from tte lake respectively would afford _a key *• *2» solution of the problem. So far we *«f been unable to collect sufficient. nuteri« for ttS .tudy, and all that c*n M "4 ifr the preiTnt is ftat «ha «*>»*/. ff these salmon:are in most.caie* GWP>nw "read"; with any degree of •^»l»»*^- i- . "The desired data made their »PPeag ance at an unexpectedly early date eerir in December, 1930, lew than tw»J«j* and one month after the l*w**»« «* »f fry-when three specimen* of AtW>tic»lmon caught by anglers about A«»M. Mth, and 30th November, were [or^WW" 1 *o Wellington from Chrwtchurch *r±*KA.; W. Parrott, Biologiat to the. Fr«|h Water Research Committee, at the; in» stance of the North Canterbury AccUn*tisatibn Society. These fish were reapectively 22. 22%, and 23 inches in 1«»8W* and weaned respectively, 3%, 3, and 3«ft. There couH be no possible doubt as.*• fiieir specific identity. In appearanet they were typical Salmo salar at. the griise stage, though probably more alender : «» shape than the average European grill* •f t¥e same length... % "•^{"J.^T acters scale count, number of gill f«*« r»' and body measurements they conform** to the specific characters of -Satoo mI»X. The most remarkable character about them is the exceptional growfli «nd. development which lave taken pl*e*J*J *" age of but little over two years.. Thwjji not an effect of bemg placed in "virgin water." for Lake Colendge hat been stocked with brown tw* te«a«r wai* though rainbows at present an Qn Horn** nant game fish and in meant aaaaoM nomerous land-locked quinnat i sahM« i _Jf pated to be of excellent quality and Sf^t. ing po*«> h*ve been caught in the lake. These latter have been derived fro* stoj* which originally ascended from the sea by way of the Rakaia River before oom»«fctie* with that water-way was cot off by the hydro-electric scheme." :