NATURALISTS’ FIELD CLUE

Evening Star, Issue 19078, 22 October 1925, Page 4

NATURALISTS’ FIELD CLUE

VISIT TO SULLIVAN'S DAM A very pleasant outing was held on Saturday m the vicinity of Sullivan b Dam. On the higher levels of the surrounding hillside there hjive at one time been dense cedar forests, and on the lower levels pine trees grow, giving the locality the name of Pine Ireo Hill, which has now been shortened to 1 me Hill. Bota,ideally the place is very interesting, for hero nioy ho found repi osentatives of almost every tree in the district. In the immediate vicinity of the dam the larger trees have been cut out, and the land is now heavily clothed with a dense growth of shrubs and young trees of the second growth—coprosmns, meleajtus, aristotelia, and nothopanax predominating. Nothopiinax simplex, variety parvum. which is rather rare, grows here. In the depths of the hush thoro is a wealth of ferns, filmy ferns, and mosses. NATIVE FRESH-WATER FISH. At the indoor meeting on Monday evening the address was given by Mr Geo. Howes, F.E.S., the subject being 1 Native Fresh-water Fish.’ It was stated that the native birds and animals of New Zealand wore well known to ho small in number, but not many people realise that the fresh-water fishes are but few in number also. Now Zealand being isolated from other land masses, any life that could not . cross the sea was barred out—and this applies to fresh-water fish as well as to plants and animals. Since the advent of the white race, carrying with.it new fish to prey on and compete with the native fish, the numbers of these latter have steadily decreased, and it is probable Unit some species are already.extinct, while others occur only in limited areas, such as the small streams in.the moi'c inaccessible, mountain districts. Though certain species arc riot strictly fresh-water fish, they penetrate into the river mouths and sometimes ascend considerable distances. The most .notable of, these is the kahawai. This is widely known ns the New Zealand salman,"and as this fine fish has many of the characteristics of the _ salmon the name is not inapt. It is beautiful, splendidly proportioned, and of graceful linos. The color % greenish grey above, spotted on the back and sides, the spots being much duller than those of the trout and salmon, and the underside is clear and white. The iris of the eye is vellow, the tail is strongly forked, and the fish is built for speed and is a strong fighter, as those who fish at the mouths of rivers often find.. The. fish taken are usually 71b to 81b in weight, hut very largo specimens also occur. The bullhead (katheostoma sp.) is a river fish which at one time was common in all our rivers, especially near the month, and also occurred in lakes. The color is dark brown tending to yellowish below, with black spots along the dorsal surface. Its habit is to lie on the bottom of the river bed and to snap at anything passing over it. Its shape is a special adaptation for this, the body being flattened out and the mouth placed well cn top. The whitebait is the young of different species of galaxidte. The first run, which takes place in our southern waters usually in October, is composed of one species of gattemiatua. hut in the shoals which later follow them we find a mixed multitude of the other galaxies, retropinna, elootoris, etc. The grayling occurring in Now Zealand is allied to similar species occurring in Australia and South. America. We have at least two species of these retropinna. The Maoris call it the upokororo. The grayling is trout-like m its habits, and is sometimes taken on the fly. On the West Coast it has been taken up to 61b weight, although largo specimens such as these must be very uncommon. The body is apparently without scales. In color It is greenish brown above, slightly speckled j the underside is greyish white. It is widely distributed throughout New Zealand. The encumber smelt (retropinna sp.) is confined to New Zealand waters, and occurs in great numbers. It is a beautiful little fish belonging to the snlmonidro, and built on their graceful lines. In color they are pale brownish above, milk-white below, and have a distinct silvery band along the sides which gives tficm their common name of silveries. The kokopu (galaxies sp.) Is dark brown above, muddy grey below, and is stronglv spotted and has indistinct bars. “It may he looked for in quite small streams where a mere trickle of water with occasional pools would seom to he too small to support it. Specimens have been taken up to Sin in length. The minnow (galaxla sp.) Is the Enanga of the Maoris, ancl is one of the commonest of these small fish.

The mudfish (neochanna sn.) is peculiar to New Zealand, and baa strango habits. The fish is found in the wet coastal West Coast districts of both North and South Islands, There are no records of it being taken from streams, but, when found* it is in a small day chamber, where it lives even if the ground is dry. It retains water in the chamber. The eye is small, and the nostrils are produced into minute tubes, and the fish has special pores on either side of its body. The shark bully (cherraarnch fostcn) is a small fish of which very little is known, occurring in tho rapid upper waters of one or tiro of the Canterbury streams. The bully (gobromorphus sp.), the toitoi of the Maoris, is common in all oun waters. The eels of Now Zealand are common, and attain a great size. Tho lamprey (geotria sp.) is one of the most peculiar fish frequenting our waters. Too head is specialised to form a sucker, which is armed with teeth sot closely together. In color they are greenish black above, silvery white below, and generally about 24in long, but of slender build. A number of lantern slides were thrown on the screen to illustrate tho lecture, at tho conclusion of which Mr Howes was accorded a very hearty vote of thanks.