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propensities. Mr. Button says that having a bcaver-rat in confinement, he 

 usea to ])l!ico in its cage a vessel full t)f water, containing a number of our 

 small spocklod fish, and tlien retire to a distance ; the beast would raisa 

 itself upon its hind legs, look into the vessel, suddenly plunge in and 

 almost instantly emerge with a fish wriggling in his jaws ; in this manner he 

 would sometimes take more than 20 small fisli at a meal. 



Of the birds likely to be injurious, little need be said. The Black Swan 

 {Ci/tjyjus afratics) is now rarely seen on the rapid rivers and is almost entirely 

 confined to a few of our shallower lakes and salt-water inlets from the sea. 

 The common wild duck {Anas superciUoaa) is another enemy both to ova and 

 young fish,but these birds,like all our other wild ducks,havo greatly decreased 

 in numbers during the last few years. 



The black cormorant(P/*«/ac?-ocoraa: carhoidcs) will, I apprehend, prove a far 

 worse poacher than any other bird. Even in our lonely mountain lakes, and 

 on the upper sources of the large rivers this bird is found watching, from th© 

 dead limb of some gigantic tree, the very shallows which will some d?iv be the 

 chosen spawning beds of salmon and trout, and woe to the shoal of young fish 

 that he gets amongst, for he is insatiable. I once shot a specimen, f^om which 

 1 released three living eels, each close upon a foot long. 



The graceful slate-colored heron {Ardca Nov<x. HoUandi(r) is s6ipetimes, 

 though rarely, seen on the fresh waters, his feeding gi'ounds generally being 

 salt swamps or quiet reedy backwaters. 



I feel scarcely inclined to mention our charming little kingfisher (Alcyone 

 azurea) for who would not willingly give up the few fish he ever takes in 

 return for the brilliant contrast he exhibits, to the sombre foliage overhanging 

 the rivers, where he dwells in such strict retirement that the fisherman or 

 naturalist seldom sees more than one in a day. 



As we fortunately possess no piscivorous reptiles, I now pass at onc^e to the 

 lowest of the Vertebrata, the fishes ; and I can safely affirm that no fresh 

 waters in the world, so well adapted for salmon or trout, are more, free from 

 voracious fish than ours. It is ti'ue that the little speckled fish, {Galaxias 

 sp. ?) erroneously called trout and two allied species, are yery numerous in our 

 rapid streams, and that these and the indigenous grayling may prov^ destruc- 

 tive to ova and to the young fish, during the first ten weeks of their existence, 

 but that period once passed, the fry will be free from further attack. 



A small percentage of both ova and fish will doubtless be taken by eels, as 

 though never plentiful in such situations, they are^ occasionally found in the 

 rapid gi'avelly parts of our rivers. 



The large fresh water fish called by colonists the * * black fish" only inhabits 

 those rivers which run towards our northern and western coasts ; it frequently 

 attains a weight of four or five pounds, and may certainly prove a formidable 

 enemy, but from personal inspection of one or two rivers in which they live, 

 and from the accounts of those who have watched them, I am inclined to 

 believe that during their nocturnal excursions for food, the black fish never 

 roam far from their daily hiding places, namely, holes in banks, and under 

 roots and logs. 



In several rivers, formerly tenanted by great numbers of black fish, and 

 which have been much fished (such, for instance, as the North Esk and 

 Piper) they have steadily decreased in number for several years past. 



Of crustaceans, fresh water shrimps of several species, and the small crayfish 

 {Astacus sp. ?) are, as far as is at present known, all we need fear in the 

 southern portion of Tasmania; but in the north and west, the latter fellow 

 is represented by a monster, attaining a weight of six or eight pounds, whose 

 powerful claws will prove of great service in removing gravel from the spawn- 

 ing beds in the search for ova or embryo fish. 



Amongst insects the larva of various dragon flies {Lihellulidce) are both 

 numerous and destructive. 



The large water beetle [Dytiscus sp. ?) and its larva (abundant in deep weedy 

 holes) are occasionally found in running water, and, be it remembered, they 

 are never there for any good. The rapacity of these insects is something 

 astonishing. I have seen the larva dart upon a large tadpole, weighing far 

 more than a salmon three weeks hatched, and kill it almost instantly. Upon 

 examination, the victim is found pierced through by the aggressor's long sharp 

 mandibles. Eish, in their very eai-ly stages, would stand a poor chance against 

 these monsters, if present in large nimibers at the spawning rids. 



The larva of our lai-gest dragon fly has all the inclination to be just as wicked 

 as that of the beetle, but luckily he wants the speed, and has to approach his 

 would-be victims in a sneaking, cat-like manner, which greatly adds to the 

 chance of escape. 



