IN TOUCH WITH NATURE

Otago Daily Times, Issue 19615, 20 October 1925, Page 2

IN TOUCH WITH NATURE

THE PAINTED LADY’S FLIGHTS

By J. DRUMMOND, F.L.S., F.Z.S,

The Feinted Lady, a close connection of the Red Admiral, and somewhat similar in colours, but less plentiful in New Zealand, conducted a great migration at Wady Kurn, west of Damascus, at a height of 500 ft or 600 ft. An observer there passed through the butterflies for about 10 miles, and through smaller droves, about 200 crossing the road within 30 yards of travellers. A Painted Lady was seen sunning itseif on bare rooks in the Great Desert of Nepud, Central Arabia, at least 400 miles from any place where its chrysalis could be found.

Another cosmopolitan butterfly, Agrotis ypsilon, not uncommon in New Zealand, makes extraordinary migrations. It has a wing expansion of two inches; it fore wings are pale brown, shaded with red brown, and they have a black, kidneyshaped mark; its hind wings' are grey, with pinkish reflections. Its caterpillar feeds on the roots of grasses, stays underground in the daytime, and goes abroad at night to feed; its red-brown chrysalis, which has a sharp, spike-like extremity, stays in the ground. The perfect butterfly is most in evidence in the evening, when it may be seen in large numbers at blossoms. In some low-lying lands of the Ganges Valley this butterfly appears every winter in great numbers after the floods. It breeds there during the cold weather, but disappears as soon as the hot weather returns. In the Himalayas, about 200 miles away, it breeds through the summer. As no trace of perfect insects, caterpillars, or chrysalis can be found in summer in the low-lying country, which often is under water for weeks, it is supposed that the butterfly migrates every fall from the hills to the valley, and possibly returns to the hills in the spring. Something of the same sort occurs in Egypt, as the butterfly appears, often suddenly, as a pest in Upper Egypt at the beginning of winter, and disappears almost a suddenly in the following spring. In New Zealand Agrotis .ypsilon, as a perfect insect, has been reported in January, February, and March.

Mr C. B. Williams, who is chief entomologist to the Ministry of Agriculture in Egypt, and who is giving close attention to the migrations of butterflies., states that in almost all cases migrations of insects, apparently, are in one direction only. By a migration at a particular time, the migrants might reach better conditions of food or climate, but the flight of large flocks of butterflies straight out to sea, and the Painted Lady’s almost yearly migration from Northern Asia to Europe, where it cannot survive the winter, and from which there is no evidence of any return, indicate a blind influence for forced movements. In some instances, the Painted Lady flies in the teeth of strong winds. Observations in Sinai show that there the wind is the most important factor in the Painted Lady’s migration, but the position of the sun may have a slight effect. The contour of a country may have a definite effect on the course of some insects’ migrations. Some follow coastlines. Along coasts and rivers the route may be followed by means of sight, but little is known as to the distance to which the insects can see, and no conclusion can bo drawn in that direction. In many instances thundery weather follows an insect migration, and collectors have noted that insects generally are more active on hot oppressive evenings that precede a thunderstorm.

Painted Ladies have a habit of flying in short strings of four or five individuals in a fol)ow-my-leader style. If one Painted Lady flies past another Painted Lady, the second one will leave its occupation and follow. Some insect migrations consist of only one sex, usuallv males, and the sex instinct sometimes is associated with migrations. Mr Williams is continuing his investigations into this interesting subject, but he confesses that entomologists, with a few hundred fragmentary records, are far from any solution of the'probloms involved in insect migrations. This is not surprising, in view of the fact that after many years' co-operation and many hundreds of thousands of observations and experiments, students of bird migration have not reached an explanation that can be generally accepted

A bellbird that stayed with Mr and Mrs H. F. Ohaffey at Asbestos Cottage, Upper Takaka, through the winter, left for a more congenial habitat two days before the first fait of snow in September. As the fall, interspersed with rain, continued for twentysix consecutive days and nights, it showed its wisdom and meteorological sense in getting away. It had not returned when Mr Chaffey wrote on September 26. “The birds left to us,” he stated, “are two blackbirds, one song thrush, two tomtits, several ground larks, a few white-eyes, and chaffinches. The number of white-eyes has been depleted. At last night’s muster in the front garden, where all the birds assemble to look for food immediately prior to more snow, making a noticeable feature during the past three weeks, there were only two white-eyes. The blackbirds and the song-thrush competed greedily for worms. Judging by the store they laid up, they wore preparing to stand a siege. They do not appear again until the snow beings to melt. Ground larks are about all the time, and enter the dog-kennels for what they can get. Knowledge possessed by some animals of approaching weather 'conditions cannot be attributed solely to blind instinct. There is some other influence. Even human beings at times become aware of an impelling power that is beyond them. Men who live for years far from their fellow-men feel this power, which induces to certain actions at certain times. A towndweller cannot conceive it, or heeds it only slightly, because his mind is occupied by many distractions.”

A resident of Waipukurau, one of the most enthusiastic naturalists in New Zealand, has sent a note on an unusual nesting of the song-thrush. He writes:—“ln Hawke's Bay the spring has been late. Though high, dry, and sheltered, my lawn has been cut only twice. This morning I flushed a song-thrush from her nest in the ground. It was at the foot of a rush-bush, but was quite apart from it. About an inch of the nest was above the surface of the ground, which must have been dug out to accommodate the nest. A neighbour who was with me at the time had found a nest similarly situated. Neither of us had ever seen such a thing before, and he suggests that the lateness of the spring may be responsible. There is so little foliage that the nests would be fully exposed to discovery, and to destruction by wind, which has been blowing continuously for weeks. Possibly these birds may have been baulked in their efforts to establish a nest in trees. If so, it is rather cute of them. It will be interesting to note whether, having made the experiment, they will continue tho practice in normal seasons.”

The handsome North Island crow has been heard by Mr J. B. Pratt, secretary of the Waitomo Acclimatisation Society, Te Kuiti, on only a few occasions. Pie reports that it is rare on the eastern side of the railway, but plentiful on the western side twelve miles out beyond Te Kuiti to the coast. Ho praises the song of the North Island wood-robin—ho uses its pretty Maori name, Pipitoa—and states that in his district it is fairly plentiful and acts up to its reputation for friendliness, following bashmen all day and feeding on grubs they put in its way by their work. White-heads, tomtits, riflemen wrens, and grey warblers are fairly plentiful there, but the general position is summed tip by Mr Pratt in a few regrettable words: “The fate of our unique and wonderful bird-life, through the destruction of tho forests, is enough to make one weep.”