Artuur.—On the Brown Trout introduced into Otago. 477 
loamy soil, in some parts marshy, and has a fall of only 4 feet to the mile. 
The river-bed consists of clay, overhanging banks, and a gravelly bottom, 
and in its course is extremely tortuous. It has also plenty of fine weed- 
beds, as nurseries for fish-food. The water is deep and has very litle 
current and no stream, consequently there is an extraordinary range of 
water. It is discoloured sometimes by gold-mining works slightly. This is 
the Upper Taieri, where most of the great trout are, and it has an altitude 
of 1,800 feet above sea-level. The food-supply is not as yet well ascer- 
tained. It certainly does not include our smelts and whitebait (Retropinna 
richardsonii and Galazias attenuatus), which are anadromous, and only 
found within a certain distance from the ocean ; but I believe I am correct 
in saying that it consists of crayfish, fresh-water molluses (Limnea), flies 
with their larve, beetles, grasshoppers, and of fish, bullies and minnows 
(Eleotris gobioides and Galaxias fasciatus). So far as my own knowledge 
goes, I am satisfied there is not by any means a great number of these two 
latter fishes in the Upper Taieri, and bottom feed generally is not super- 
abundant. The great weight attained by the trout must evidently then be 
the consequence of a fair supply of food, both surface and bottom food, but 
more particularly the unusual range of water and the excellent shelter 
afforded by the river’s banks. The Shag River, in its upper waters, flows 
over slate formation, being a good deal affected by silt from gold-mining 
operations ; and in its lower waters over shingle, gravel, and sand, with 
good pools and plenty of range ; while the whole course of the Water of 
Leith is over trap boulders, and it has few pools, with little shelter except 
from bush, and no range of water. The food in both is generally similar to 
that in the Upper Taieri; but besides that they have the great advantage of 
an endless supply of the migratory fish, the smelts and whitebait. The 
Shag River fish, living within the limits of migration, therefore, of these 
little visitors, are fat and well-formed and still fairly plentiful, the largest 
trout being near the tidal way, and small trout numerous above. The 
larger trout, however, are not now found in the Leith except during the 
spawning-time. Fishing has fallen off very much during summer ; and this 
winter, for example, although Mr. Deans searched the Leith several times 
carefully, he found no large fish till a big flood had come down. This proof 
is of course negative, yet when the smallness of the stream, and want of 
water and shelter are considered, it seems reasonable to believe that as large 
trout are not now seen in the Leith except during winter, they must live in 
the brackish water at its mouth or in the bay itself, for nine months out of 
the twelve. And this is further borne out by the fact of many large fish 
being netted by fishermen in the bay, with the characters more or less of 
the brown trout. 
