Chapter V: Introduction (4)

Sir Frederick kept watch with one of the people who had reported it. And, sure enough, what appeared like a long black reptile appearing and disappearing, or like a school of porpoises, rising and disappearing, came into view. But Sir Frederick had binoculars and was able to make out that what to other people had been a long black reptile was in reality a long line of white-breasted cormorants in flight, on their way to their roosting quarters. As they flapped steadily along they were plainly evident, to the naked eye, as a moving black line; as they paused in their flapping and sailed on motionless wings they became invisible to the naked eye, though, of course, still visible through the binoculars.

IN NEW GUINEA Once, for a few startled moments, I thought I had a sea serpent before my very eyes. It was on the middle Fly River in south New Guinea. We were camped on a bamboo-covered bluff overlooking the river. Though about one hundred miles from the mouth, the tide made itself strongly felt here, and there was an abundance of driftwood. This driftwood, varying from freshly uprooted trees that had fallen into the river to waterlogged timber that had been long in the river, went up and down on the tide until it got out in the main channel and so on to the sea. One day at lunch, sitting in front of my tent, I was idly watching the driftwood. One piece in particular caught my fancy. Apparently it was the root of a partly submerged log, projecting about three feet above the water, and curved at the end so that it looked like the neck and head of a reptile with a casque on its head. Knowing it was a waterworn root, in fancy I even saw its eye. I called my companion's attention to it, as here was as close as we were ever likely to get to a sea serpent. Then, the "head" turned. It was alive. For a few startled moments it was a sea serpent. You can imagine our amazement at having a piece of driftwood that we had in fancy turned into a sea serpent come to life. Investigation became the order of the day. The binoculars that were constantly at hand were trained on it. The reality came as a further surprise. Our sea serpent was the head and shoulders of a cassowary which was swimming the river. Later I found that these large, ostrichlike birds, which have a large casque on their heads, are well known to swim, but I didn't then.

This seemed an ideal opportunity to collect a specimen. These birds may weigh up to 150 pounds. When shot in the forest there is the question of lugging them perhaps miles to camp. Here was one swimming up to our door.

We sat quietly waiting for it. But our native boys had seen it too, for next I saw them rowing the dinghy to it. An oar was brought into play to stun it. And then both the boys and ourselves found out something else. Dead cassowaries sink. When the bird was stunned by a blow of an oar, it disappeared below the surface and was never seen again.

CONSERVATION OVER THE TELEPHONE

Richard Orr, the _Tribune_ reporter, called me one day about bronze grackles. It seems that the Chicago _Tribune_, in their "Day by Day on the Farm," had told about the grackles on the _Tribune_ farm. A _Tribune_ reader wrote in, expressing surprise that grackles were permitted on the _Tribune_ farm and gave details of destruction by grackles of other birds, personally observed. What were the facts of the case? Should grackles be tolerated? Or should they be eliminated? Orr wanted to know.

This is the sort of question that is difficult. It is important, too, for it involves basic conservation issues. And there is no sharp, clear-cut yes-or-no answer. The question as to the grackle's character reminds me of the character of Moses, as explained when I was in school by a professor of the Bible: The black was there and the white was there; Moses was a character sketch in gray. And so with most creatures. They're both good and bad from our standpoint. Grackles certainly do kill other birds at times, and interrupt the nesting of some of our favorite songbirds. And yet, liking birds as I do, I tolerate them in my garden. On a trumpet vine on our garage in Chesterton, Indiana, one year we had a grackle build its nest on top of a domed English-sparrow nest. The young of both sparrows and grackles hatched about the same time, and the two families, within six inches of each other, were successfully raised without friction between the parents.

Quite evidently grackles are not always killers of other birds. As to robins or grackles being the "better" birds, if we had a robin's nest that we prized, and the grackle killed the young in it, the grackle would be "bad." But if we were an inquiring farmer, and had to weigh the grackle against the robin, we might find the grackle "good" and the robin "bad." The grackle feeds its young vast quantities of insects harmful to the gardener; the robin sometimes seems to specialize in earthworms. Earthworms are beneficial to man, passing through the earth, making air and water more accessible, and, by passing earth and vegetable matter through their intestines, enrich the soil.

The house wren that warned the _Tribune_ reader when the grackles were about is often prized as a garden bird; it is bold, saucy in appearance, and a vigorous songster. But it is also well known as a quarrelsome bird, prone to punch holes in the eggs of its neighbors, and it also may fill up with sticks nesting boxes so that other birds cannot use them.

The above was the gist of what I told Orr, and appeared in the May 5, 1950, _Tribune_.

Thinking of it afterwards, as is usual, I thought of many other things I could have said, and perhaps made more clear that no bird is all good or all bad, from our human point of view. Their relationships with the rest of the landscape are complex. I like to see butterflies flit about my garden. But butterflies are caterpillars at one stage. And caterpillars may eat some of the things in my garden. But some birds feed on caterpillars. If I eliminate the caterpillars because they eat the plants I like, at one stroke I eliminate the source of the butterflies I like, and food for some birds I also like.

Perhaps the partial answer, if answer there be in this imperfect world, is summed up by moderation: I can have some butterflies, some caterpillars, some plants, and some birds in my garden. If one becomes too abundant and interferes with the others, I prune it. Maintaining some sort of a balance, we can have some of each.

BIRDS WASHING FOOD

We not only wash ourselves and our clothes, but certain items of our food are regularly washed, as spinach, to get the sand out of it. Washing has been so important in our society that we've coined the term "Cleanliness is next to godliness." Possibly we've the snobbish idea it's a strictly human trait. Among other animals we don't expect to find water used for such cleanliness, and the raccoon, who does wash his food, is considered a sort of biological oddity.

But when we come to birds we find a surprising number of them that wash their food.

The dipper of our Western mountains in Oregon has been seen to wash insects and grubs before feeding them to the young birds. The parents held the food crosswise in the bill and the head was twisted rapidly from side to side in the water. Not until then was the food taken to the nest for the young.

The scene shifts to Africa. Four buff-backed herons were feeding on a flooded lawn at Gezira, Egypt. One of the birds captured a large insect, apparently a large black beetle. Holding the insect in the tip of its bill, the bird walked to the water, immersed the beetle three times, shaking and fumbling with it the while, and then swallowing it.

Then in Britain came a whole host of records, after an observation in Holland in 1946 of curlew sandpipers washing food. The birds were probing the dry mud at the edge of a little creek. When one of the birds got a small sand worm, it at once ran with quick steps to the creek and stepped into the shallow water, where it dipped the worm a few times into the water before swallowing it. Then it trotted away for more. The editor of _British Birds_, the journal in which this was published, suggested that this might be a more common habit than the scanty published records would indicate, and invited observations.

A spate of records resulted in the succeeding numbers of the journal: a whimbrel washing crabs; a snipe, earthworms; godwits washing their food; with curlews it was reported to be normal; dunlins, greenshanks, redshanks, ringed plover, and oyster catchers were all reported doing this until it appears that with the group of birds we call shore birds--sandpipers, snipes, plovers, and their relatives--it may indeed be normal. The details of the observations strongly suggest that the reason for the washing, in many cases at least, is the same one that underlies our washing spinach; to get the sand and mud out of it.

HOW ANIMAL VOICES SOUND TO FOREIGN EARS

When in El Salvador in 1951, I found that the common barnyard animals had much the same voices as the ones with which I was familiar in the United States. But when I saw their utterances written down it was another matter. The voices written in Spanish sometimes looked as different as the names of the animals written in Spanish. Take the donkey, for example (or _burro_, as they call it in Spanish). In English we call its "song" "Heehaw!" In Spanish they wrote it for me, "Aja! Aja! Ija! Ija!" There were a number of German scientists at the Instituto Tropical de Investigaciones Científicas, where I was working, and for comparison I asked them to write for me what the same animals said in German. The burro (_Esel_, they call it in German) says, "_Ihå! Ihå!_" in German. Despite the difference in the appearance of these words, when they were pronounced by the various nationalities they sounded very similar. Compared with the original assinine pronunciation, the Spanish version was awarded the prize for being the best rendition of the beast's voice.

The cat's "_Miau, miau, miau_" in Spanish, "_Miau, miau_" in German, and "Meow" in English were all very similar in appearance as well as sound. The duck's voice came out differently. In Spanish it was "_Cuá, cuá, cuá_," in German "_Wack, wack_," and in English the initial "Cu" or "Q" sound of the Spanish, and the final "k" sound of the German are united into "quack." The hoot owl came out much the same in pronunciation, though it looked different in the Spanish "_Ju_," in German "_Hu_," and in English "Who."

The cow's, the pig's, and the frog's voices were also rather similar in the three languages: the cow's in Spanish being "_Meu, meu, muuu_," in German "_Mŭh, mŭh_," and in English "Moo"; the pig's "_Grup-grup, wink_," "_Óŭik, Óŭik_," and "Grunt, oink"; and the frog's "_Cruac, croac, croac_" "_Quak, quak_," and "Croak." The barnyard rooster has a difficult voice to transcribe in letters. In Spanish it was "_Quiquiriguiiii_," in German "_Kickeriki_," and in English "Cock-a-doodle-do." After listening to the various renditions by the various nations I could see how each rendition came into being, but as for deciding which was closest to the original I hesitated to choose.

When it came to the dog, the discrepancy was surprising: in Spanish it was "_Guán, guán, guán_," in German "_Waŭ, waŭ_," and in English "Bowwow." The German and the English are close enough. But though I went outside and listened to the dogs in Salvador, never did they seem to say, "_Guán, guán, guán_," though I must admit that neither did they seem to say, "Bowwow."

SIGHT IDENTIFICATION

Sometimes when I'm trying to decide whether the birds of the Cameroon Mountains of West Africa are the result of one invasion and variation _in situ_, or of two invasions, or whether the Himalayan red-billed choughs of Ladak are different from those of Nepal, or how the molt of the cassowary resembles that of penguins, I am called to the telephone to identify a bird someone has seen.

The chances are it's a starling. I've not kept a record, but I fancy half the questions are on identification of starlings. In the distance starlings are black, and people know them. But close up, where details can be seen, they puzzle people with their variety. The young may be dull brownish; the adults may be speckled in the winter; in the spring the speckled tips of the feathers wear off and they're all black. But the black is iridescent, and in sunshine glitters purple or greenish. And the bill color changes too: it becomes yellow in the spring.

Sometimes it's surprising how you can spot a bird from a brief description. Take this one: a bird that sits with its stomach on the ground, and has a big mouth, and long whiskers; a whippoorwill obviously. Or take this one: a bill like a chicken and with flat feet at the back; obviously a pied-billed grebe.

There was one that absolutely stumped me for a day. The lady said it had a bill like an eagle, and a tail that stuck up. For the rest she was vague. Often habits, actions, or habitat are a help to me in placing a bird, but I could get nothing to help--not even where she had seen it. I admitted I couldn't help her. The next day someone brought in a picture puzzle out of a newspaper, and there, right in the center, was my bird. It was a dodo! We don't mind helping people learn things, indeed we consider it part of our job, but to help them work puzzles is too much!

MY LESSON Sight identifications of most students probably contain errors. On common species it's not important, as quantitatively they cancel out. But when a bird tripper, anxious to make a new record, wants me to help him decide he saw an exotic tern, I'm very careful--I've had experience. Rarities have to be checked on all points, not identified by elimination or on a few key characters. One of the best lessons of caution I had in New Guinea. It was in the mountains. Each morning I hunted in a forest where I'd found a new genus of bowerbird. Anything might occur, I thought. Then I saw flying through the treetops what could only be a magpie. A long-tailed, black and white bird, its pattern was unmistakable. There was nothing like it known from New Guinea. It would be an extension of range from Asia. Or it was a new and unknown species. Anyway I needed it as a specimen. But it was shy and eluded me. Morning after morning I haunted the forest. Finally I got the bird. And it turned out to be a partly albinistic specimen of a common, black, long-tailed bird of paradise. The abnormal white areas in its plumage had fooled me completely. But it helped teach me caution as to sight identifications.

One of my Gary friends, Mr. Raymond Grow, who is a keen bird student, has the proper approach, as his identification of a winter duck showed. There were a number of unusual winter birds that season (1951-52): brown-headed chickadees, pine and evening grosbeaks, and red-breasted nuthatches, all from the North, were present. It was the sort of winter one expects other rarities from the North.

DUCK CAUSES CONFUSION Mr. Grow had seen at the edge of Lake Michigan a duck he didn't know; it was boldly patterned in black and white, a big duck. An immature male eider seemed the only possibility. He came into the museum and we went over specimens, noting the difference in the shape of the head between the king and the common eider. He studied the descriptions and the plates. Nothing quite fitted. Unsatisfied, he went back to Michigan City, found the duck again, and suddenly realized it was a muscovy duck, partly albinistic, and escaped from someone's barnyard.

It's not the first time a muscovy has caused confusion. Only a year or so ago we had a duck sent us from the Philippines that our correspondent wrote was shot swimming in a river with a Philippine mallard and surely represented a new species. But it turned out to be a muscovy whose original home is tropical American but has become domesticated and transported by man to far parts of the globe. Occasionally birds escape and take to the wild, even as this Philippine bird had done.

GREEN HUNTING JAYS TURN BLUE

Sometimes in "working out" a bird collection things get dull. In identifying the specimens, and writing down why they are this species, or that species, or subspecies, it seems routine; as though it were simply routine putting things in the categories ready for them.

Such was my feeling one day as I worked over Himalayan jays and magpies from Nepal. I'd done the yellow-billed blue magpie, and the red-billed blue magpie, which both fell into their places smoothly. Then I got out the literature, the pertinent keys, and descriptions for the next species, the green hunting jay. It's a beautiful, pale, apple-green bird, with a green crest, and set off by dark red wings. It checked with the descriptions, and I wrote _Kitta chinensis_, its scientific name, on the label. Then, to check the species' identification and to determine the subspecies, I turned to the collection, to the birds from India, Siam, and north Indochina, which should all be the same.

I pulled out the drawer--and blinked at the jays, rows of them; all pale blue with brown wings. I looked at the name on the case, on the tray, and the name on each specimen. They all said the same, _Kitta chinensis chinensis_, and it was the bird described as green, like my new specimen. It was uncanny. The new green specimens and the old blue ones were identical in size, in structure of bill, crest, feet, tail; they must be the same. And they were. The book, I found, described how the colors changed with age, and in John Gould's magnificently illustrated folio, _Birds of Asia_, published in 1861, he had the green hunting jay depicted both as a green bird with red wings and, in the background, a "blue" green hunting jay like our museum specimens. When alive, and when freshly killed, the birds are green. But with the passing of time the green changes to pale blue, and the red wings to brown wings. Probably my new specimen, now a year old, is less green than it was when fresh. And when twenty years old, like our museum skins, it will be blue too.

The riddle was solved, and it fits into a well-known phenomenon, "museum age" or post-mortem change. "Foxing," we call it for short. We see it in the male American merganser, where the lovely rich salmon color of the fresh bird becomes plain white. The emerald cuckoo of Africa has vivid rich yellow under parts when fresh, and this too becomes dingy white. Gray Canada jays become more brownish. Birds that are olive or other shades of green tend to become more olive; brown birds tend to become more russet or foxy (hence the term "foxing"). We keep all our specimens in dustproof, lightproof metal cases. The change is not caused by fading. Apparently it's a change in the pigment, perhaps from oxidation.

Taxonomists, the men who classify and name birds, have been fooled by it. Old skins used to represent the birds of an area may give a quite different idea of what they are like than do fresh skins, and when skins of different age are compared, the conclusions may be wrong.

Foxing is one of the pitfalls for the unwary taxonomist, and something he has to guard against.

HOW BIRDS USE COWS AS HUNTING DOGS

The sportsman out for quail or woodcock uses dogs to drive out the birds for him. Starlings and cowbirds about Chicago use the same principle in hunting grasshoppers. Instead of dogs they use cows, though of course the cows are intent on something else and presumably unconscious of the fact that they're helping the birds.

As the cow grazes slowly across a meadow, it scares up grasshoppers close in front of it. The cowbirds and starlings take advantage of this. Instead of covering the meadow on foot, constantly alert for a sitting grasshopper, or to chase one they flush, the birds keep with a grazing cow. They take up a position by the head, or a foot, and catch the insects the cow disturbs. The cow is so much larger than the bird that it is likely to flush more insects. The grasshoppers on the wing are much easier to see than when at rest in the concealing grass, and some fly directly toward the bird. Too, the grasshoppers fleeing a cow are less likely to be alert to other dangers.

CONFIRMED BY OBSERVATION The advantages of this to the bird are obvious. But we've just assumed they were, and we had no data on the relative efficiency of the two methods of hunting. A few years ago, however, while in El Salvador, I was able to get quantitative data proving that using a cow as a beater was advantageous, as we suspected, and showing how much more effective it was, something we did not know.

The bird concerned was not the starling, which does not occur there, or a cowbird, which occurs but consorts little with cows, but was the grove-billed ani, a black cuckoo about twelve inches long of the tropics of Central and South America. Like our starling and our cowbird, it kept with cows, catching the grasshoppers and other insects that flew up. Both anis and cows were common in the grassy fields about our headquarters in San Salvador. We decided, my son Stanley and I, to watch anis with cows for a few hours, and then without cows for a few hours; thus getting the average rate for each type of feeding. We quickly found it wasn't as easy as that. Something always happened; even on the levelest and most open fields the birds were constantly disappearing behind a tuft of grass, or in a hollow, or, if nothing else, behind the cow's head or feet. Then, too, the ani we elected to watch wouldn't pay attention to the job in hand. It would wander off, or go to sleep. And sometimes, when we were about to discontinue watching a somnolent bird, it would snap up an insect. Perhaps it had been watching all the time. Finally we found we had to record observations of many short periods, of from three to fourteen minutes each, and add them together.

By dint of much patient watching we got our data. In the dry season when insects were scarce and the grass short, it took an ani, hunting alone, two minutes on the average to find an insect. In the same length of time hunting with a cow the catch averaged three insects. Thus hunting with a cow as a beater was three times as effective as hunting alone.

The effect of the change of the season in abundance of food for the ani was very striking. In the wet season the grass began to grow fast, and insects became common. Then the anis had an easy time. Without a cow an ani averaged between three and four insects a minute, more than six times as much as in the dry times. There was less incentive to use a cow as a beater, with food so abundant, but when the ani did so, its rate of finding insects was still higher: between four and five insects per minute. In a table it looks like this:

_Average Number of Insects Per Minute Found by Ani Feeding_

WITHOUT COW WITH COW

Dry Season .5 1.5
Wet Season 3.4 4.7

But the three-times-greater-results in a given time in the dry season do not tell the whole story as to the effectiveness of using a beater. When an ani was hunting by itself it walked about, covering a surprisingly large amount of ground. When using a cow as a beater, not only did it catch more insects in a given length of time, but it also walked about much less, saving a great deal of energy.

This is not true co-operation between cow and bird, for they're not working together toward a common end. It's not exploitation of the cow by the birds, for the cows lose nothing. It is closer to a form of harmless parasitism, for the ani profits from the activities of the cow without either harming or helping the cow. It also illustrates how sharp birds are--ready to take advantage of any factor in their environment that will help them get their food.

EARLY BIRD LISTING

I wonder how many of the people who go out making lists of spring birds know that bird listing goes back to ancient times. It's a modern sport, but earlier bird watching was serious, and a competitive listing of birds played a part in as important an event as the selection of the site of the city of Rome.

The story, as Plutarch tells it, is that Romulus wanted the city on what became known as Roma Quadrata; Remus wanted it on the Aventine Mount. As was the custom in those days, they concluded at last to decide by a divination from a flight of birds. The twins placed themselves apart at some distance and watched. Remus, they say, saw six vultures, a truly notable flight; Romulus saw twelve and from this rare and unusual occurrence Romulus' choice of the site for the city was accepted.

VULTURES HIGHLY REGARDED Partly from this the vulture became chiefly regarded by the Romans in their divinations from birds. But even before this the vulture was highly regarded. Hercules, it was said, was always very joyful when a vulture appeared to him upon any occasion. He considered it the least harmful of creatures; not pernicious to corn, fruit tree, or cattle, it never killed or hurt any living thing. It was also thought not to eat other birds, a weighty point in its favor, as Plutarch quotes from Aeschylus, "What bird is clean that preys on fellow bird?" And apparently its deciding claim to esteem was its rarity and infrequency, which gave rise to the opinion in some that it came from another world, an opinion foisted by the soothsayers of the day.

Earlier yet, birds played a part in Rome's history. Plutarch warns that some give you mere fables of the origin of Rome, but it is widely current that Remus and Romulus, fathered by Mars, the God of War, were exposed in a remote place to perish. This would have taken place, but for a she-wolf that nursed them, and birds of various sorts that brought little morsels of food which they put into their mouths. Some, however, hold the belief that not birds of various sorts but a woodpecker was the bird that constantly fed and watched the twins, and even in Plutarch's time the Romans still worshiped and honored the woodpecker for this service to the founder of the city.

BATTLE OF THE SEXES AND ITS EVOLUTIONARY SIGNIFICANCE

I used to think that the battle of the sexes so ably portrayed by James Thurber was artificial, a man- and/or woman-made thing. But recently I've come to see it as old--probably as old as sex itself in the animal world.

Under the severe tide, "Secondary Sexual Characters and Ecological Competition," in a paper from the Bird Division of the Chicago Museum, I've outlined the possibility of competition for food, between the sexes, being a factor in evolution, responsible in part for characteristics of structure and traits that distinguish them.

In circles that discuss evolution the idea is current that food competition is important between species. It may even be stated as a rule: two species with the same food habits cannot live in the same place. Competition drives one out, unless they have different food habits. These differences seem especially evident when you look at closely related species, and they are accomplished in a variety of ways. A habitat difference is very common. The long-eared owl hunts in the woods--its cousin, the short-eared owl, hunts the meadows; the song sparrow favors the drier shrubbery while its cousin, the swamp sparrow, lives in wetter shrubbery.

THE SIZE FACTOR Sometimes the difference is accomplished by size; take the downy and hairy woodpeckers of our wood lots, very similar except that one is larger and is adapted for larger prey, the other smaller and adapted for smaller food items. Sometimes they feed differently, as the Baltimore oriole, which picks flowers and pecks through their sides, while the orchard oriole probes into flowers as they hang on the branches. Thus more individuals of several species live in an area.

When a pair of birds "sets up housekeeping" and starts "raising a family" they can no longer drift about, looking for easy living and places where food is plentiful. Their wanderings are restricted by having a fixed point, the nest, as their center of interest. Two individuals must draw on the food supply from an area about the nest. Competition would be extreme, and, if there were a scarcity, perhaps critical.

We know how different the sexes may be; how different the rooster is from the hen in our domestic fowl, or the drake and the duck in the mallard, or the red male and the green female of the scarlet tanager. These sexual differences have mostly correlated with display and mating. But logically there should be differences in feeding behavior and adaptations between the sexes.

The basic idea is contained in the old nursery rhyme:

Jack Sprat could eat no fat,
His wife could eat no lean;
And so between them both,
They licked the platter clean.

The two birds of a mated pair, limited to a single area, could be expected to have different food preferences or adaptations for getting it. And we find that there are cases of this. The most striking is that of the huia from New Zealand, of which I've written in a Chicago Museum bulletin. Both sexes have similar food preferences, especially wood-inhabiting insects, but they get them in different ways. The male has a short, straight, stout bill for digging out the wood-boring grubs, woodpecker fashion; the female has a much longer, slender, and curved bill for probing into holes for them, creeper fashion. The female may get grubs in wood too hard for the male to chisel. They supplement each other.

DIET VARIATION BY SEX It is possible that further study may show more sexual differences to have a feeding advantage; the larger size of female hawks fitting them to take larger prey; the smaller size of certain female songbirds fitting them for smaller prey, the smaller bills of female hornbills, the straight bill of the male western grebe, and the upturned bill of the female. Perhaps all are of advantage to the species in giving each sex slightly different advantages in getting food.

Selection could have its effect in the populations with most sexual difference in feeding habits being most successful in raising and leaving progeny. Thus, slowly, differences between the sexes would accumulate. However, it must be kept in mind that this sort of evolution would be limited. The drifting apart of the sexes would be checked by the necessity for their coming together periodically for at least a short period, at nesting time.

WATER IN THE DESERT

Water is a precious thing in the desert. Without it no life is possible. When rains come plants spring into vigorous growth. During the long stretches without rain they rest, some as seed, while some plants store water in root systems, or in large trunks. Animals have developed a number of ways of surviving long dry spells in arid country.

Among mammals the kangaroo rat of our Southwestern desert seems able to get along without water. This is caused by an arrangement within the body whereby the necessary water is manufactured within the animal from other foodstuffs: metabolic water.

The accessibility of drinking water in a desert may be the determining factor in whether or not some birds can survive there. The nests of Gambel's quail must be close enough to drinking water for the newly hatched young to walk there, else they perish of thirst. It has been said that newly hatched chicks of the related valley quail of California cannot travel more than a few hundred yards from their hatching places without water. Broods hatched farther away are doomed to die.

Sand grouse, relatives of the pigeons that have adopted the general appearance and habits of quail, live in the Old World, primarily in arid or even desert areas. Where they occur their daily traveling to water is a well-marked phenomenon. Their flight is swift and powerful, and though they may traverse long distances of barren, inhospitable country to watering places, their punctuality in arriving at water, morning and evening in some species, is remarkable.

But what of the young of these desert dwellers that need water? A most unusual situation exists; indeed it seems to be unique. The old birds bring water to the young! This has long been recorded, but as recently as 1921 it has been questioned. However, Mr. Meade-Waldo's observations on birds in captivity seem to definitely establish the custom, and its methods.

PARENTS CARRY WATER Both birds incubate the eggs, the male by night, the female by day, and both parents care for the young. But it is the male only that brings water to the young. He rubs his breast violently up and down on the ground, and then, his feathers awry, he gets into his drinking water and saturates the feathers of his under parts. Then, in captivity, he would run to the hen, make a demonstration, whereupon the young would run out from under her, get under him, and suck the water from his feathers. This they did by passing the feathers through their bills, continuing and changing about until the supply was exhausted. It was found that until the young can fly they take water in no other way.

This was in captivity. Presumably in the wild the process is the same, the adult flying with wet under parts from the water hole to the resting place where the young are under the care of the female.

The similarity of the young sucking water from the feathers to young mammals suckling their mother has been pointed out. But another and a truer similarity exists: that of the young sand grouse getting water from the feathers, and young quail getting water from dew-wet leaves in areas where dew is heavy and there is but little surface water.

BIRD GRAVEYARDS

The best-known stories of animal graveyards are those of elephants. But when I asked the curator of mammals about them the answer I got was little better than a snort. Apparently the evidence for them is so vague that it's little better than a myth.

But in birds we have a few bits of evidence from far-scattered places that occasionally such things as graveyards exist.

In the antarctic Dr. Robert Cushman Murphy found on the island of South Georgia a place where Johnny penguins went to die. It was in a lake in a coastal range of hills. The lake bottom was thickly strewn with scores of penguin bodies, all of which had apparently died a natural death. The icy water, Murphy thought, might preserve them for years. The hills, away from the sea, seem a surprising place for the graveyard of such aquatic birds as the penguins, but it correlates with another peculiarity of their mental makeup. They like to nest on high land, or at least far from the sea. The blind instinctiveness of much penguin behavior is well shown by these birds when there is no high land on their nesting island. Then they may nest so far from the beach on which they land that they are close to the water on the other side. Yet they always returned to the sea by the long route, never taking the shorter route.

Another aspect of this preference for land distant from the sea is shown by their behavior when threatened with danger from man or dog. They flee away from the sea, back onto the land, when safety for them actually lies in the sea. Presumably this fixed behavior dates back to the time when the seal that is called the sea leopard was the penguin's main enemy. Then the sea held their only danger. With man's arrival the situation changed, but only after considerable experience with man do the birds change this behavior.

Apparently, when the time came for the penguins in this South Georgia graveyard to die, they followed their age-old pattern, climbing to the high country and away from the sea.

IN A HOLLOW TREE In a hole about eighteen inches in diameter and twelve feet deep in the trunk of a wych elm in Hants, England, Ursula M. Grigg reports finding the bones of at least ninety jackdaws, thirteen starlings, six green woodpeckers, and twenty-five stock doves. All the remains were clean, and not much broken or decomposed. The idea that these bones were the remains of owls' or other predators' feasts was discarded for a number of reasons; as was the idea that this had been a natural trap, the birds entering to roost or nest and being unable to escape. The most tenable idea seems to be that this was a favorite roosting place in winter, and that during the severe weather old and weakened birds, roosting there, succumbed and added their bodies to this communal grave.

ON AN ISLAND Another instance comes from the little Cape Verde Isle of Cima in the South Atlantic. A photograph in the _National Geographic_ magazine for 1927, Vol. 52, P. 27, has the caption that this island is unique and uninhabited and covered with the tiny bones of millions of petrels which in ages past have come here to die. Certainly the plate shows an amazing litter of bird bones on the tiny plateau of this islet.

Petrels are mostly pelagic birds, coming to the land only to nest on isolated islets. Can this "graveyard" be merely the normal accumulation of the bones of the nesting season mortality, or can it be that the birds actually come here to die?

ANIMAL GARDENS

Best known of the "gardens" and "animal husbandry" of the lower animals are those of the ants; the aphis kept by the ants for the sake of a sweetish secretion, and the underground fungus garden of the ants. In the vertebrates I know nothing comparable to this, but we do get a number of cases where there is a definite relation between the animals and the growth of vegetation.

It has been said that in the antarctic the nesting colonies of some penguins are detrimental to the vegetation. The constant passing and standing of the birds on the limited areas of soil preclude the growing of vegetation over sufficiently large areas to be an important factor in hindering plant growth. But the reverse is true of the Johnny penguin in the Falklands, where it is sometimes known as the best farmer in the country. The Falkland Islands, off southern South America, are cold, wet, and windy. Sheep raising is one of the main industries. And the Johnny penguin helps to provide better pasture for the sheep. The birds nest in colonies and their droppings help to enrich the land so that the grass grows taller and richer. Rather than using the same area for their breeding colony each year the birds select a new, clean area at the beginning of each breeding season, so that they improve the ground over a larger area.

From the arctic comes another example of a relationship between bird and plant. On the arctic barrens, here and there, are large boulders, erratics left by the glacier that covered the land in times past. And on these boulders, and here only, one finds patches of bright yellow or reddish lichen known to scientists as _Xantheria_ or _Xanthoria_. Apparently its presence is owed to the fact that these boulders are the lookout places of snowy owls, hawks, and other birds. Their droppings, falling on the rocks, provide the nutrient layer necessary for the growth of the lichens. It is probable that these lichens are transported from place to place by the birds carrying the soredia on their feet. In recognition of the close relationship between these lichens and birds an ecologist has coined the rather formidable term "ornithocoprophilous" to express the relationship.

Also in the arctic are the arctic-fox gardens. The arctic fox often makes its burrows in sandy places, and about the entrance to the burrow accumulate remains of former meals, fox droppings, and suchlike animal debris. This in time enriches the soil and the vegetation there grows taller and more lush than elsewhere on the barrens. This lush vegetation attracts the small, mouselike arctic rodents, the lemmings, that feed on green, succulent vegetation. There is of course one further step in this chain. One of the important foods of the arctic fox is the lemming, which he thus brings to his door by the richer vegetation he unwittingly causes to occur there. A charming arrangement, one of the old naturalists called it.

DROPPING THINGS

The story is well known, being recorded by Pliny, of how the poet Aeschylus came to his death through a bird mistaking his bald head for a rock and dropping a turtle on it. The bird was evidently the lammergeier or "lamb vulture," one of the largest and most magnificent of the Old World birds of prey; nearly four feet long. In the Atlas Mountains of North Africa its normal food is turtles, and these it cracks open, so that it can get at the meat, by carrying them up into the air and dropping them on a rock. Now it lives in the Himalayas and in Africa, having been almost if not completely exterminated from Europe because of its alleged predation on sheep. Not only turtles but bones are treated in the same manner, to get at the marrow. Though the habit is well known, it is surprising how difficult it is to find a firsthand description of it. So far I know of only one description written by an eyewitness. And yet, in East Africa recently a stony mountaintop was found littered with broken bones that seemed to be the result of the lammergeier's habit.

GULLS DO IT As I have mentioned, gulls open clams and mussels in this way; and crows, which are among the most intelligent of birds, do it also. They pick up the mussels left exposed by the falling tide, fly up above a hard stretch of beach, a big rock, or a stretch of nearby paved road, and drop the shellfish there. While in general this practice is restricted to a few groups of birds, it is practiced by them in many far parts of the world. The Pacific gull of Australia, widely separated from its near relatives, has the same maneuver for opening shellfish as has our herring gull.

It's hard to understand just how this habit came about. One can imagine that some birds found it out by accident when flying about with a stubborn "nut" they were unable to crack. Or perhaps it was in play they found it. The raven is known to fly about carrying and dropping things in play.

SPARROWS DO IT TOO Often, to find a background if not an explanation of a habit, we look about to see if it's used in some other connection. I've already mentioned the play of some of the crows. Only one other "dropping" habit has come to my attention, and that is a single record for the very common house sparrow. Edmund Jaeger writes that in Nebraska, and again in Riverside, California, he saw house sparrows on gravel roofs, dropping small stones over the edge. The pebbles, or small bits of crushed stone, were carried to the edge of the building by the sparrows, dropped, and as each pebble was dropped the sparrow turned its head, apparently the better to watch or listen to the pebble fall and strike. No obvious utility appeared in these actions. It, too, looked like pastime. Perhaps there was no better reason behind them than that behind small children dropping stones down a well.

LEARNING BY BIRDS

Of course birds can learn. Indeed there's a trite saying that no animal has been discovered so low that it cannot learn. One of the simplest cases of learning is shown by parts of some experiments I carried out years ago on the curve-billed thrasher. I had raised a number of these thrashers by hand, and in connection with finding out about their tasting abilities I first fed them on the white of egg, hard-boiled and cut into little squares. They liked it. Then I soaked more squares of boiled egg white in evil tasting (to me) formalin. The birds came to the dish, and also ate them. But after that for a week they refused to eat such egg white. They had quickly learned to avoid the ill-tasting food.

BAD-TASTING FOOD Once I hand-raised a barred owl from a nestling to adulthood. Sometimes getting food for it was a problem, and upon occasion I fed it frogs, which it seemed to like well enough. But then came a day when I fed it a toad. The owl seized the toad at once. Now toad skin, presumably as a defense weapon of the toad, secretes a substance irritating to the mucous membranes of some animals. And this was evidently irritating to the owl, for it did not hold the toad long in its bill. It spat it out, and the owl's face gave evidence of disgust. After that the owl not only refused to take toads, but it also refused to take frogs such as it had found palatable before. Evidently frogs looked too much like toads. The learning was effective, and extended not only to the original object, but also to other, similar objects.

BUCKET-DRAWING When in Florida with the Archbold Expeditions I was studying blue jays. A very simple but amusing thing that chickadees learn is to sit on a perch and pull up a little container of food that dangles far below the perch on a string. Jays, along with crows, are among the most clever of birds, as I've said before, and I gave two jays in one cage a chance to learn the trick. In three days one of the jays was regularly and quickly pulling up the little bucketlike container and getting its food from it. The process was simple: the jay reached down, seized the string in its beak, secured the slack under its foot, and reached down again for another pull. Sometimes five separate pulls were needed to raise the food bucket the eight inches to the perch.

The jays were regularly fed in this manner. Soon I noticed that only one of the two birds pulled up the bucket, though the other also fed from it. In effect one was depending on the work of the other. After this had gone on for a month, I wondered if the second jay, which had never done any of the work, would be able to pull up the bucket if left alone. Certainly it had had lots of opportunity to learn by seeing its cage mate go through the motion. So I left it alone in the cage. This second jay, despite its chances to learn by observation, took one day longer to learn how to pull up the bucket of food than had the first jay. The jays certainly learned the trick quickly through a trial-and-error process, but simply watching the process seemed to be of little help in learning it.

CAN BIRDS COUNT?

If birds can count, it's a rather rudimentary thing--perhaps no more than impressions of the size of groups. The widely known example showing that birds don't seem to distinguish between one and two persons is the ruse used by bird photographers and students of birds who are using blinds from which to watch the birds at close range.

The hide, or blind, is a little hut built perhaps a few feet from the nest to be photographed. If the photographer enters the blind in the sight of the parent birds, and conceals himself there, the birds who saw him go in will be a long time in coming to the nest and in resuming their normal activities. But if the photographer takes a companion with him, both go into the blind and conceal themselves, and then one of them goes away leaving the other concealed, the bird quickly disregards the intrusion and goes about its activities as though no one were left in the blind. This subterfuge has long been used and is very successful. Apparently the bird is unable to distinguish between the two people that arrive at the nest and the one only that leaves, and behaves as if both had gone away.

In my duck-hunting days a duck hunter who used wooden decoys told me he was sure that there was a certain number of decoys necessary before they were effective.

The decoys were wooden blocks, carved and painted to resemble life-sized ducks, weighted to float like them, and anchored in shallow water in a flock within gunshot range of the blind in which the duck shooter sat. The idea was that ducks flying by would see the flock on the water, assume that here was a safe resting place, and fly in and light, or attempt to light among them, giving the wild-fowl gunner an opportunity to shoot the wild birds.

The duck shooter claimed that if less than twenty-five or thirty decoys were put out in the flock, the setup was much less effective than if more than twenty-five to thirty decoys were used. He thought that the ducks could distinguish between less than twenty-five or thirty and more than twenty-five to thirty, and favored the latter. Though this is distinguishing between greater and lesser amounts, it hardly comes in the category of counting.

DISTINGUISH "MORE" FROM "LESS" However, a series of experiments summarized on Page 121 in the periodical _Bird Banding_ for 1940 seem to indicate that birds can distinguish between different numbers of things, such as peas and numbers of dots. The birds, including pigeons, parakeets, and jackdaws, were trained either to choose a certain number of objects under certain circumstances, or to choose between two quantities of objects with reward and punishment motivation. It was found that these birds were able to distinguish up to a maximum of six. That this is really counting in the human sense of the term, which is linked with speech or written symbols, is improbable, but it does indicate, as one would expect, that birds do at times distinguish between different quantities, and sometimes with considerable precision.

COURTSHIP FEEDING

A young man, giving his best girl a box of chocolates, and a bird, giving his prospective mate a worm or a berry, have this in common: they are both practicing courtship feeding. Further, humans and birds are the only vertebrate animals that do this.

With birds, during courtship, the female often begs to be fed by acting like a young bird--with fluttering wings and widely gaping mouth. The male normally places the food he has collected directly in the open mouth of the female.

The significance of this courtship feeding has been discussed especially by David Lack, in the scientific journal, the _Auk_. It seems that in courtship feeding the food as such is not of primary importance. The female does not need the food she is begging for; indeed she may have had a full meal since her mate, whom she is soliciting, had last eaten. Perhaps it is of help in maintaining the bond between the pair during the period that exists before they have a nest and young to look after. In this connection it is interesting that with waxwings during courtship feeding the fruit that the male gives the female may be "handed" back (by beak) and the food exchanged back and forth.

In looking for significance and correlations in courtship feeding we find that some species practice courtship feeding and some do not. And the birds that do practice it are usually those in which both sexes care for the young. It might be considered an early, useless appearance of a habit that later becomes useful when the male feeds the incubating female and helps feed the young.