WILD LIFE IN NEW ZEALAND

Otago Witness, Issue 3495, 1 March 1921, Page 54

WILD LIFE IN NEW ZEALAND

By the Hon. G. M. Thomson, F.L.S. No. 107. May one who is not an entomologist write authoritatively on the insect life of the country without being considered a very presumptuous being? The term naturalist is commonly applied now to w ho studies, not all kinds of natural objects, but chiefly anima’te forms. It should be used for anyone who is a lover of Nature, and especially an observer. But so great has become the necessity for concentration on one line of research, or oil one group of organisms, that the individual who aspires to the wider field of knowledge has to confine himself to generalities. We have a number of able entomologists in New Zealand who possess a good knowledge of the whole class of insecta, but to name only three of them, Mr G. V. Hud son has especially devoted his attention to the lepidoptera ('butterflies and moths), Mr D. Miller to the diptera (flies), and Dr Tillyard to the neuroptera (dragon flies, etc.). We must go to these gentlemen or other specialists for exact knowledge of any group. Yet it is possible to have a fair general knowledge and much specific information which may be of vast interest to amateurs like myself and many of my readers, and so I am going to make the attempt to interest others in what has proved to be of much interest to myself. Perhaps the best way to do this is to commence with some of the insects which I meet with in the garden, and this may lead us on to a wider field. Certainly the most conspicuous insect in the garden at the present time is the humble bee. which is a good deal in evidence bustling into the larger tubular flowers, foxgloves, snapdragons, pentstemons, and the like. Humble bees are such commonplace things nowadays that many people, especially young persons, do not realise that they have only been in this country for a few years. How well do 1 remember walking home through the Town Belt from the Otago Boys' High School on the afternoon of 12th February, 1888— just 33 years ago,—and how excited I got on seeing a humble bee flying past. I followed it till it went over a hedge into a neighbouring garden. I had not seen one since leaving the Old Country in 1867. Next morning I was full of the news, but found that my colleague, Mr Wilson, had seen one on the same afternoon. Within the week Mr Mungo Watson, Professor J. H. Scott, Mr Jas. Wilkie, and Mr W. Stuart (all of whom have joined the majority) saw these bees in town and suburb, Mr C. B. Chapman reported them from Waihola, and someone else saw them on the llawea flats. Where did they come from? I need not here go into the complete history of the introduction of these insects ; they are among the few which have been brought to New Zealand for economic purposes. Out of about 290 species of introduced insects which have at one time or other got in to this country only about two dozen have been introduced of set purpose. They are : two kinds of hive bees, four of humble bees, the silkworm moth, and a number of ladybirds and inchneumon wasps, the two latter groups being imported to destroy other insects which were found to be dangerous and expensive pests. Mumble bees wore first brought into Canterbury in 1883, earlier attempts in 1873 and 1876 having failed. Red clover or cowgrass (Trifolium pretense) was somewhat extensively grown in New Zealand for fodder, but the plant dies out after a few years, and has to be constantly renewed from. seed. But in early days if settlement it was quite rare for the p’ants to produce anv seed, for the flowers are incapable of self fertilisation, and it requires an insect with a sufficiently long trunk to reach the nectar at the base of the flowers to cross-polinate them. The clovers are not tubular flowers—they belong to the same family as the pea and bean, —but' they require an insect heavy enough to press down the keel to get either at the pollen or the nectar. Occasionally honey bees visit the flowers of the red clover for pollen, and this may explain why iny old friend Mr William (Martin, of Fairfield, once got a large quantity of very fine, seed off a small patch of red clover as early as 1858. But, speaking generally the plant was not producing seed and so the Canterbury farmers resolved to introduce humble bees so os to bring about this desirable change and thus not have to import foreign seed to keep their pastures well supplied with this most excellent fodder plant. It is easy enough to sav that you are going to bring humble bees from Britain to New Zealand across the equator, but to do that in the days of sailing ships, and before the introduction of processes for producing chilled air, was a problem. The wonder is they ever got them here at all. The bees had to be collected in winter, from holes in the ground and from among moss, where they were lying dormant, and Dr Frank Buckland, who was the first to attempt their introduction here, offered in the Lincolnshire newspapers a small sum for each live bee brought him. All humble bees dormant in winter are fertile queens. Curiously enough the Canterbury people specific 1 Bombus terrestris—the large earth humble bee —as the particular insect they wanted. This v.as because Charles Darwin, the

famous naturalist, had mentioned this as the kind of bee which visited red clover. But Darwin had not examined into the fact for himself, and it was pointed out later by another naturalist, Fritz Muller, that the trunk of this species was too short to reach the nectary of red clover, and that the work of cross-fertilisation was probably accomplished by one of the longer trunked species. When a, boy goes out to dig up humble bee’s nest in winter it is not likeiy that he will be particular about the species. Indeed, he is not likely to lcno v v ety much about specific differences, though he •vill probably have bis own distinctive marks and names for them. When r was a small boy we used to call th 9 common black stone humble bee (Bombus which was common in Scotland, the British humble bee, because it had a red tail. British soldiers were mostly red-uniformed, and we thought it patriotic to annex any species which wore the national military hue. The whitetailed ones (B. terrestris, B. lucorum, B. ruderatus, and B. hortorum) we termed trench bees, while a big, yellowish, hairy tellow (B. distinguendus) was the foggy or Russian bee. These names had nothing to do with the geographical iange of the species, they were the popular terms of the countryside. When the Lincolnshire rustics brought in dormant humble bees they did not look to see that they were specimens of Bombus terrestris; as \ matter of fact they brought anything they could find, and it was only later seen that they' were of four different species. . first successful attempt made to introduce these insects into this country was by a Mrs Belfield, of Timaru; but there are no details available as to the number liberated, and there is no record of their increase. Then, in 1885, two lots reached New Zealand, 93 bees surviving (out of 542 which were shipped), and these were set free near Christchurch. They increased at ail extraordinary rate, and very shortly after it was found that the red clover on the Canterbury Plains was beginning to ripen its seed. So the original object for which the bees were introduced was quickly achieved. Nor do 1 know of any evil effects which have followed this successful effort at naturalisation. How they spread and increased in these early days! In January, 1886, two were seen by Mr J. D. Enys on Castle Hill, on the V est Coast road, 64 miles from Christchurch, and others at Mount Peel. 90 miles in another direction. Early in 1887 they were reported from Kaikoura, 100 miles to the north, and from Timaru, 100 to the south. At the end of the year they had made their way up the ' Waitaki Valley, through the Lindis Pass, and on to the Hawea flats. In February, 1888, they appeared in Dunedin, as I have mentioned, and at Waihola, 30 miles to the south-west. In November, 1889, they were first recorded from the head of Lake Wakatipu, and in the beginning of the following year were observed in tne neighbourhood of Invercargill. No doubt their spread to the West Coast and to Cook; Strait was equally rapid, but there is to record. Both whole nests and single queens were sent from time to time to the North Island from Canterbury, and were seen in Wellington in 1888, and in Auckland in May, 1890. They became thus fully established in New Zealand in less than 10 years. So rapid was the first increase of the humble bees that apiarists began to take fright, and it was very commonly feared that soon the hive bees would be crowded out from the flowers, and that no nectar would be left for them. In some districts, as in thistle-infested areas, the bees swarmed to such an extent when the plants were in flower as to deter tirmi persons from going through. This extraordinary rate in increase was not maintained. After a time the numbers became reduced, till in some districts where they were formerly abundant they became almost rare. In most parts of the country now, though humble bees are fairly common, they are nowhere so abundant as to constitute a pest or even a menace. The causes of this diminution in numbers have never been investigated, though a few observers have sought to give some explanation of the facts. Mr W. L. Sladen, who is a leading authority on humble bees, says that it is damp, and not cold, that the queens try to avoid, and that is why their burrows and shelters in Britain usually have a northern exposure. In this country Mr Hopkins, who has written about the history' of the introduction of these insects, considers that the rainfall is the chief factor, and that those portions of Marlborough, Canterbury, and Otago where the annual rainfall is under 30in, are best suited for the growth and increase of the bees. But this is only a surmise, and there is no direct evidence on the subject. We need continued observations on the occurrence of the bees, the causes of their death, and what are their enemies here. The lifeliistorv here needs working out. cold?” Vickers: “Cousrhinff!”