THE PHOTOGRAPHY OF GROUND-NESTING
BIRDS.
THE PHOTOGRAPHY OF GROUND-NESTING BIRDS. (A New Method ?) BY
E.
C.
SHERWOOD,
M.A.
I AM a recent convert to ornithology, who can number my ' seasons ' on the fingers of one hand. Most of my time has been spent upon ground-nesting birds as being easy to photograph. Like many beginners I started with the ' stnng method, focussing the camera on the nest and working the shutter from a distance. The difficulty lay in the focussing, which is necessarily a matter of chance even if the bird is to be taken sitting and not Walking on to or alighting at the nest. So I quickly abandoned that plan in favour of a fixed ' hide ' made with a tent. As soon as the bird has become accustomed to such a hide, the observer can be put into it by an accomplice ; then if he is careful he will be able to focus to any degree of accuracy, and change his plates without disturbing the bird when once she has returned. Where time is no object the method is perfectly satisfactory ; the hide can be set up one day, brought nearer and the photograph taken the next. But when only half a day, or even one whole day, is available the method may fail for lack of time, or may, if the hide is set too close, result in the birds deserting the nest. That was the difficulty which led me to design a movable hide, which can be set up at a distance and gradually worked towards the sitting bird. It consists of a light framework capable of being taken to pieces for transport, covered with casement cloth, and roughly camouflaged in green and brown. Its outline is that of a diminutive haystack. The back gable-end has an opening through which I can crawl, fastened by tapes. The front has two openings, the upper fitted with a small sheet of celluloid sloped away from the hide at its lower edge. This serves as a window through which the bird can be clearly seen, but through which it cannot see, provided the interior of the hide is reasonably dark, because of the reflection of the bright sky in the celluloid. The lower opening is circular and into it is sewn a short sleeve, the other end of which receives the lens of the camera. The sleeve allows the hide to be moved along the ground a few inches backwards or forwards while the camera remains in the same position. Inside the hide is a wooden box which serves as a seat and also as a Support for the camera which is strapped to a platform mounted upon a universal joint.
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THE PHOTOGRAPHY OF GROUND-NESTING BIRDS.
Myfirstattempt was made upon an Oyster-catcher (Haematopus ostralegus, L.), rather a shy bird. We set up the hid accomplice and I, some thirty yards away from the nest; he put me inside and walked ostentatiously away. While the cock-bird was reconnoitring and the hen making tentative efforts to get back to the nest I set up the camera, tied the lens in the sleeve andfilledthe pockets in the sides of the hide with shingle to keep it from blowing away. Then in about a quarter of an hour, as soon as she had settled on the eggs, the advanc began ; first the hide was pushed forward as far as the sleeve would allow, that is until the lens of the camera and the sleeve were right inside the hide. Next the seat and attached camera were thrust forward tili the lens was pushed outwards towards the nest as far as it would go without moving the hide. These two processes were continued alternately very slowly and steadily, resulting in a step of about nine inches. And though the bird never took her eye off the hide the whole time, I got within eight feet of the nest without driving her off. The advance took the greater part of an hour, and succeeded I believe, because each movement being directly towards the bird, she was unable to detect it. Probably a certain amount of fluttering in the fabric of the hide in the breeze served to mask its forward movement. After exposing all my plates I began to retire the hide, and my accomplice Coming up the birdflewaway. An hour later, with refilled dark-slides and a code of arranged signals we went back, hoping for some ' walking-on ' and ' going-off' photographs. The hide was worked up again, this time much more rapidly. When in position, a white handkerchief displayed from the back of the hide made the accomplice walk slowly towards the bird ; its withdrawal signalled ' walk away.' Whenever the accomplice got within about two hundred yards the bird would spring off the nest; but she returned immediately he retired, and the process could be repeated as often as desired. The only other birds tested were terns, which proved far less shy. One Little Tern (Sterna minuta, L.) was quite difficult to dislodge, when I wanted a picture of her in the act of alighting at the nest. I had no accomplice that day. Noises had no effect; she did not go even when I sang to her. A single pebble did nothing but make her cast a surprised and indignant glare at the spot where it landed. One such pebble, lobbed at her, feil on her back and stayed there. I took its photo ; and at last got her to rise, but only by tossing a handful of shingle over her from a hand put out under one side of the hide. She was back again, even then, almost before I was ready for her. On another occasion I secured a photograph that I could hardly have hoped to get in any other way—Little Tern feeding their young. Atfirstthe parents would not feed the chicks anywhere
THE PHOTOGRAPHY OF GROUND-NESTING B I R D S .
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near the hide ; but I followed them up as the chicks scrambled away, tili at last they had to give in. I cannot say that the method has been fully tested. Next year I hope to attempt Redshank (Totanus calidris, L.) and Stone Curlew (Numenius arquata, L.). With them it will be a question of pegging down the hide at some distance from the nest for a day or two so that the birds may get used to its appearance, and then of advancing it from this original position. I think the method will succeed : in any case I am sure that it has solid advantages. There is the economy of time, both one's own and the bird's : she is not kept away from the nest for longer than is absolutely necessary. Moreover the hide can be made so light as to be easy to carry, and mobility counts for much in field work. It may be asked why not attach the camera to the hide so that both can be moved together, and the somewhat cumbersome advance by steps avoided ? The reason is this : if there is the lightest breeze blowing the hide is constantly on the tremble, and the camera must not be attached firmly to i t ; the interposition of a sleeve between camera and hide secures immunity from at least some of the shaking. I wonder whether the method is really new ; it is new to me, but so obvious that I quite expect to find some correspondent writing to say that he used it before I was born.
SATIN MOTH, Liparis salicis, LINN.—In 1929 the imago was very common in Gorleston and Yarmouth during the second half of July : sitting on young poplars that bordered Middleton Road especially, among poplars everywhere in the town ; on foliage and more often trunks ; and on walls. It came to light freely, was commonly seen Aying at dusk ; and scattered wings showed it a frequent prey of bats. It was most abundant between 17th-25th July. Egg-patches were observed everywhere, on trunks and leaves, on stakes supporting young poplars, and upon fences near them. During August and September minute larvae were very common on poplar and willow, of which every leaf was riddled with minute depredations. In 1930 fully grown larvae were seen in numbers during early July, leaving the trees to pupate as well as still upon them. Fullgrown larvae in profusion were seen on l l t h July upon fences of the Links in Caister Road ; on 14th the first imago was observed in Gorleston, when larvae were still feeding, some not even in the last instar. Up to at least 21st August the imago was Aying in Caister Road.—E. P. W I L T S H I R E .