OUR PUBLIC SCHOOLS COLUMN.

Otago Witness, Issue 2862, 20 January 1909, Page 95

OUR PUBLIC SCHOOLS COLUMN.

¥01t SENIORS AND JUNIORS. (Conducted By llagistbb. 1* whom all c«asMuuicatioDs must b* addressed.) A FIELD DAY FOR THE BIRDS. Last week I guve the first part of the paper which Dr Fulton, at my request, placed at my disposal, and this week 1 give file ■concluding' portion : — i Ibregtjxab Laying. (Continued.) " It has been suggested that the irregular laying might be a result of the parasitic habit and tuue been a<xjuired by the female through having to retain the "egg until a suitable nest is found in which to deposit it. This theory can be put on one side by ■what we know of the American cuckooa, ■which we find have the habit, but are mot yet fully parasitic, proving- conclusively that his peculiarity of ovipositing' precede.? parasitism, besides which it is not uncommon in other birds. Alay not this peculiarity have been acquired for the very purpose of having- birda of various ages in the nest, so that each .'•uoooeding egg may get the advantage of the warmth of the body of the previously hatched chicks, while the mother is away foraging on Lehalf of her offspring The same thing, according to Mr Bos worth Smith, is seen in the barn-owl. He says, ' Alone, I believe, among birds, she sometimes lays her eggs not continuously, but at considerable intervals of time. At first, it may be, she lays ,two eggs, on which she will sit for v week or two; then two more; and then, when she has hatched the first two, perhaps three more; so that you may find fre-sh eggs. ! herd-bet eggs, and young birds in the same nest. What is the reason of this peculiarity? Is it that by leaving the later eggs •to be hatched in part at loasfc by the ■warmth of the young birds she lias more leisure by an all-night absence to satisfy the cravings of her voracious brood? The male owl, though remaining faithful to his mate, does not assist in the hatching of the eggs, and the female, with so large a number as six or seven chicks to feed, has acquired the advantageous method of keeping her eggs warm in 'her absence.' "Pigeons have the peculiar habit of laying pairs of eggs at intervals, and of having eggs, small chicks, and fairly large ones in or about the nest at the same time. This, no doubt, is partly for the same reason of supplying vicarious warmth while the parents are on the search for food, but also in order to further the production of as many chicks as possible in the one season. Our New Zealand hawk has this habit also, on occasion, of depositing its eggs at intervals, and here again the same reason comes into piny. Hawks have much hunting, soaring, and searching away from the nest before they can get food for their toungry little ones; and this irregular laying no doubt enables the uncovered eggs and young to withstand the effects of the frequently inclement weather. These birds are all most voracious feeders, and the utmost efforts of die parents are necessary in otsder to- provide sustenance and satisfy their clamorous offspring. "There is another possible reason for the irregular laying of eggs. Young cuckoos and cowbirds are so voracious and thcMr natural insect food so unsatisfying that in those cases in which the parasitic egg is hatched the intruder finds it expedient either to throw out, or, by seizing all food, to starve to death in a few days, the rightful tenants of tfhe nest. May not the mother bird through countless ages have witnessed such a struggle in her own rude nest, and unconsciously finding one youngster alone of a largo brood, and that the strongest or oldest, to survive, have gradually com© to lay her eg-g-g at intervals, so that at no tame would iaad for a biixi at ouc age be

exactly suita.bls in quantity ot quality for a bird at an older or younger stage? Soft grubs and other minute insects for tho tiniest chiolc ; moths and butterflies for the iiext in. size; caterpillars and other hairy insects for stiil la.rgea- ; iw.tLes and hardhacked cockchafers and crickets for tho next; and finally lizards and even small frogs for those about to quit the nest. Does it not seem likely that an advantage would be gained by that mother who had her chicks separated by the widest intervals in ages, so that, having satisfied with some trouble the greedy eldest, she could witth more leisure attend to the next in size, and finally, with little trouble, the tiny demands of the infant? "So with our 'hawks the mother would have to supply beetles, worms and maggots for the little ones, frogs' and lizards for the next, pieces of carrion, chicken, etc, for the large. The difficulties of feeding a. brood all of the same size would be so much the more difficult that it lseasy to see how irregular laying lessens the burden of feeding the young. "Some 12 months ago I was in the Waimate district, and a friend with whom I was staying took me to a harrier's nest ho knew of in a tussocky, dnied-up, little swamp. The nest on a nigger-head, was empty, but after some snuffing round of his dog we routed out a phtmp young bird, I suppose about three weeks' old, c<nered | with soft down, and as big as a fair-sized ■ .pullet, nearly the size of the bigs^st bird in our picture. Some more yelping and sniffing' disclosed a-ncther bird a good deal bigger, %cry savage, almo.t completely fledged, and probably a v.cek or mere older. A still mere closer search amonf impenetrable raupo aaid nigg>er-hoad^, among which we had to go on our hands and knees, and the third, and largest, bird was frmnd. This was a nearly adult bird, fully feathered in fine black plumage, a dangerous fellow to tackle, md on,e whom the dog was very chary of approaching. | However, with the help of slips o ? phormium tenax we noo&ed his lesra, ivnd eventually , got him by the wmg tips, when he wa>i , quite helpless. He could get over the groand in great sweopmg hops, and when we approached too near he would lie o\er on Irs back, with wings outstretched, hit"ing like a cat and sta-iking at us with beak and wings and Talons. Now. no doubt, many of you have ofrsn seen young hawks i of different sizes belo<r<?. but I doubt if j anj of j"ou worried your heads over the i why and wherefore. Many of you ha\e caiccras, and nearly all cf you at some time or another liav« a week or co in the country. Try to find some nests in ; 6 wain p or field, and photograph them in ! situ, and bring in your photos, and some ' of us will endeavour to nave them repro- i doicad in magazines or our transactions. A bird somie of >ou should try, to photograph is the dotterel, which appears in Otago paddocks about August and September, stays with us a few weeks to breed, and then m.ig4-ate3 further nontJi and inland They fly swi fitly to and fro or run up and down the ploughed fields, and jerk their heads up as though throwing out their little chirp of whio whoi. If you get near i<ts iiest it will lie down and nutter like a woundied bird along &he ground wiih one wintr trailing in order to tempt jou into imag-inii27ig- you can just catch it. You will stoop and fun and ru<n and stoop, and then suddenly the audacious lktle bird will rise with a flutter from your very finger tips and away as vigorously as ever, literally laughing at you for having been co easily led away from its nest. The ' pointed eggs are laid in a depression of the ground, and are so stone-like in colour that you aie hardiy likely to find them except by accident, or unless you eefc jour- , self to watch the birds from a distance ' with a pair of field glasses, gradxially a»nd slowly approaching them, and the moment the pareart bird plays ' the broken wing game ' sit right down and carefully ie\iew the situation. By the bird's .-uiric-s jou | will 6oon find the dlreoticn ir dtvs "not \ want you io go. and a blow and careful

progression in that direction will generally result in success. In that very excellent Public Schools' Column, conducted by 'Magister,' there appeared recently an account some of you may net have " read of the cleverness of the dotterel. One of these birds, playing the decoy in the vicinity of its nest, was observed by the correspondent to drop suddenly beside a tussock, and on investigation she foiir.d there, to her astonishment, a lark's nest "with three eggs, Mrs Dotij&rell skipping on as usual just out of reach. She thought this wus an accident, a mere coincidence at the time, but happened to be near the same spot next day, and to h&r woTxJer and astonishment the dotberell werat through exactly the same performa-nce, leaving no doubt in her mind that there was a dehberait-e attempt to deceive her imto mistaking the lark's eggs for her own and that bar own eggs would benefit by the lark's misfortune. Is this instinct or reason? Mr James Drummond has pointed out In one of his Nature columns that our kotuku, or white heron, is really cosmopolitan, and exists in millions throughout Eastern Asia, Malaya, Polynesia, and Australasia, and I have written to him suggesting that the Tourist Department should import vcmts young birds with the object of stocking each of our Botanical Gardens and mamy of our reserves with a goodly number of these magnificent creatures. If the birds are left alcne they will soon breed freely, and pro\e a- great atf-traction and welcome addition io the public places s^t apart for the education and pleaeuro of cur people. I cannot help thinking that this is an ex callent scheme, and if it is successful I shall be very proud of having originated, even in a small way, a plan for brjngmg again into our country one of the loveliest birds that v.-as ever waped out by the hand of man."'