LIFE HISTORY OF THE EEL

Hokitika Guardian, 28 December 1928, Page 2

LIFE HISTORY OF THE EEL

AN INVESTIGATION. . DANISJI SCIENTJST IN- DOM INION. AUCKLAND, Dec. 2(5. The origin ami propagation of the common.-'fresh water eel lias for centuries presented a most intriguing mystery. Ah far as a great part of the earth’s surface is concerned that itivs,l j tcry has largely been swept away by the long? and patient researches of Dr Johannes Schmidt, Directoi of the Carls berg Physiological Laboratory, Copenhagen. Dr Schmidt, who is leader of the Danish scientific expedition at present visiting Auckland on the research ship Dana, has been investigating the life history of the eel for the past twenty-five years, and the results ofvhis discoveries have been permanently. recorded in the transactions of world-famous scientific bodies like the Smithsonian Institution. As fas as the Atlantic Ocean is concerned Dr Schmidt has ’brought his laborious studies to completion,' but the Pacific Ocean and the IndiaTi Ocean still -present him with aboundance of unsolved problems concerning eel life. For some of these he lias already gathered material to work on, and to this he, to add largely as the Dana continues' her two years’ homeward cruise.

His investigations are divided into three main sections. , First there is the charting of the 'distribution of eels and discovering where they are present and where absent. . Then there is classification of them according to species’, and finally there is the ascertaining o*f their life history. It is a striking fact that eels are not found along the Pacific coast of America. The explanation Dr Schmidt offers is that the waters are too cold. Even in tropic-hl latitudes: they may be warm enough on the surface hut af great dept'hs they are not, 'Western Pacific waters hold at least twelve different species of eel, each with a distinct life history. In the Indian Ocean six different'species are known. Their distribution about Australia and Africa is peculiar/ . Generally speaking they, are found on-the east but not on the'west coasts. For several years past Dr Schmidt has given considerable attention to the

eels of New Zealand where, lie says,

they are probably more abundant than anywhere else in the, southern hemisphere. He carried on investigations at Pipiriki on the Wanganui river I'm some time last year. By means of statistical and other investigation o>f nearly 1500 of our eels he has definitely ascertained that there arc two valid species of the genus, Anguilla australis and Anguilla aucklaiidi. ’l’lie most conspicuous point of difference is that the former is short'finned and the latter long finned. The eels ol Now Zealand differ in many, ways from those of Europe, hut most notably in attaining Tar greater size. Euiopean eels rarely a length ol lout and a weight of lolh or 121 b, hut New Zealand specimens of over 301 b and even of over 401 b have been recorded. Dr Schmidt thinks it possible that species, other than these two common ones may he found in New Zealand. Four species have been 'found in Australian waters, hut of one of these only one specimen has been recorded in Australia.

The charting of distribution anr classification into species is now practically completed for the Pacific and Indian Oceans. The tracing of the I if. history remains. Dr Schmidt has al ready found (piite small larvae neai the Society Islands, and he has gather ed abundance ol materiaj on which t work. One thing is at least certain that the original home of all our cellike that of their European kindred, will be found in deep ocean waters.