Chapter 6: Bringing Up Baby

Stealing quietly along, I came in sight of the male robin, loudly calling, fluttering his wings, and in evident trouble, though I could not imagine the cause. But looking closely I saw perched on a branch of a cedar-tree a fat, stupid-looking bird, fully as big as the robin and covered with feathers, but with a speckled breast and no tail to mention. There he sat like a lump of dough, head down in his shoulders and bill sticking almost straight up, and neither the tenderest coaxing nor the loudest scolding moved him in the least. In fact, I thought he was dead till the opera-glass showed that he winked. But stupid and ugly as he looked, he was the darling of the heart in Papa’s little red breast.

Migration, territoriality, courtship, nest-building—these are all fundamental links in the cyclical chain of robin life. But each is largely without significance, without utility, without import, unless viewed in the context of the eventual rearing of babies. Baby-making, after all, forms one half of the crux of any species’ existence, death being the other half. And no matter how terribly awkward in appearance or irritatingly demanding of attention babies may characteristically seem, they just happen to be the stuff of the future.

For robins, progeny production can be conveniently divided into categories of parental activity corresponding to each of the three major phases of songbird babyhood: the egg, the nestling, and the fledgling. Lacking a more creative approach, we will proceed in that order.

First an Egg

One or two days after her nest is completed, the female robin begins laying eggs at the rate of one per day, with the morning being her favorite dropping time. Her eggs are usually glossy sky blue in color (“Robin’s-Egg Blue” has actually served as a standardized hue in our culture), but may occasionally be greenish blue or, rarely, either spotted or entirely white. Typically the shells become progressively less glossy from first-laid to last so that the female’s final effort is often quite dull. In similar fashion, her eggs also tend to become progressively smaller across a given set.

Although four eggs is the typical total, three is not an uncommon clutch size and occasionally five are laid. As many as eight eggs in one nest have been reported several times but such clutches probably always arise from the joint efforts of two different females, one of whom for some reason does not have a nest of her own. It is conceivable, however, that a single bird might lay up to six eggs. Interestingly, robins seem to lay more eggs per clutch in the northern parts of their range (for example, New England) than in the southern parts (such as Georgia), but this tendency is rather slight.

With the onset of egg-laying, Mother Robin is confronted with the problem of when to begin incubation. If she starts with the laying of the first egg, then—since eggs are laid a day apart from each other—the first-laid egg will obviously hatch one day before the second-laid egg hatches, and two days before the third-laid egg. In that case, considerable discrepancy will exist between the size and strength of the first- and last-hatched youngsters, and the latter will be at a severe and potentially lethal disadvantage in competing with older nestmates for food. From this perspective, it behooves the female to wait until her clutch is complete before beginning incubation (depending on the temperature, fertilized eggs can remain viable for several days before the onset of incubation). And in general, this is exactly what she does.

On the other hand, the cold night air of early spring could easily injure the first-laid egg if it is not protected by an incubating female. To prevent such damage, the female should ideally begin incubating as soon as she lays that first egg. And lo and behold, robins do tend to initiate incubation before their clutches are complete when local temperatures drop dangerously low. In other words, although her general predisposition is to begin incubating only after the clutch is complete, wise Mother Robin will start sooner in the face of chilly weather.

With little exception, the monotonous chore of incubation falls upon the responsible, feathered shoulders of the female. It is she who spends the entire night on the nest as well as 60 to 80 percent of the daytime, depending again on the weather: on cold days, sensing that her eggs mustn’t lie uncovered for long, she sits more continuously than she does during milder temperatures. Even during warm weather, however, the female is careful to be gone for no more than five or ten minutes during each of the one or two times an hour that she does leave the nest.

These brief and perhaps welcomed excursions from her tedious chore are necessary for obtaining food since, as we noted in Chapter 4, the female’s territorial-minded mate seldom feeds her as she incubates. Though relatively constant throughout the incubation period, the mother’s “attentiveness” (periods spent on the nest) tends to increase as hatch-time approaches. One interesting sidelight to the female’s incubation duties is the periodic “turning” or rotating of the eggs. In most avian species, embryos are likely to develop abnormally if they maintain a constant position with respect to the direction of gravity. Anyone who has ever artificially hatched chicks or ducklings, for example, knows that during incubation the eggs must be turned—either by hand or machine—several times daily so that different sides of each shell face upward at different times. Mother Robin must also rotate her eggs, so every now and then she interrupts her sitting, hops onto the nest’s rim, and gently rolls the eggs with her bill. Alternatively she may jostle her eggs with her feet while sitting upon them.

After twelve or thirteen days of patient warming aided by a special hot-spot on the female’s underside (the featherless “brood patch”), the eggs begrudgingly begin to yield their precious contents to the outside world. The shells that had shielded out environmental harshness during fragile embryonic development now act like confining prison walls that must be fractured for freedom, and each infant, tooled with a special hard protrusion on its beak called an “egg tooth,” laboriously chisels away from the inside. Struggling and resting, struggling and resting, the youngster may require an entire day before finally breaking out. Exhausted, featherless, wet and blind, the infant fatefully collapses into the next phase of its existence.

Next a Nestling

The physical development of a nestling is nothing less than astounding. Infants who weigh five grams at hatching generally tip the scales at about fifty-five grams a week and a half later—a spectacular increase of 1,000 percent in only ten days. Many other physical changes coincide with these weight gains, and together the developmental processes mirror a miraculous metamorphosis from naked helplessness to something at least approaching feathered autonomy.

Except for a few bits of tufted down, the newly hatched robin’s most striking features are its painfully pink skin, two huge but closed black eyes, a swollen stomach, a long skinny neck, and a periodically gaping orange-lined mouth. For at least the first few days, the infant is largely soundless, its body temperature rests at an abnormally low level (about 103°F), and it cannot stand or even sit upright. It can, in fact, raise its head for periods of only a few seconds, during which time it passively accepts anything shoved down its yawning little mouth.

By the sixth day after hatching, however, the nestling has opened its eyes, feather sheaths have appeared above the skin, it can hold its head up for thirty seconds straight, and for the first time the baby can actively grasp objects with its mandibles. By day eight the youngster is feathered everywhere except perhaps on the stomach, its body maintains adult temperatures of around 109°F, it can now sit upright, and its food call during parental presence approaches vociferation. By day ten or eleven the more precocious of the young are capable of leaving the nest, and only their speckled breasts, stubby tails, and smaller size readily distinguish them from adults.

We might briefly note one other interesting change that occurs during a nestling’s development—namely, the gradual appearance of the ability to show fear. In the robin, as in most animals, fear of novel or potentially threatening objects is initially absent in the neonate; such emotional responses only begin to appear after some period of maturation. The length of this maturational period varies greatly across species, being about twenty-four hours in a newly hatched duckling, a couple of months in an infant monkey, and about six to nine months in a human baby. In robins, fear first appears between the sixth and tenth day after hatching. Thus, while a two-day-old nestling will show no signs of distress when being handled, a ten-day-old nestling will struggle most violently. What underlies this gradual emergence of fearfulness is not clear, but it is not simply the development of sight since some robins do not show fear until day ten even though their eyes may have opened on day six.

Throughout the course of all these rapid nestling changes, the parents are constantly tending the infants’ various needs. And perhaps nothing reflects the solicitous nature of this parental care better than the occasional survival of a baby who is markedly handicapped in some way or other. In one report, a nestling suffered from a malformed tongue which protruded through the lower mandible and hung like a billygoat’s beard in pathetic uselessness. This baby remained fit and fat while being fed by its parents, but upon leaving the nest and meeting difficulty in self-feeding, the youngster grew emaciated under decreasing parental provisions and eventually succumbed. A similar case involved a totally blind nestling who, with diligent parental care, managed to survive to fledglinghood (that is, grew old enough to leave the nest). Quite expectedly, however, the poor youngster soon began blundering into various obstacles and twice even had to be fished from a backyard pool by human passersby. The creature’s final fate, though unknown, could not have been pleasant; yet the important point is that it had managed to survive as a nestling in the first place.

If infant robins are to endure their first two-week period of posthatch life, their parents must successfully meet the problems posed by three different nestling needs: the need for food, the need for nest sanitation, and the need for protection against both predators and the elements. Of these three labors, the most exhausting in both time and effort is the provision of food.

Food

Nestlings consume tremendous quantities of food, often amounting to 50 percent more than their own weights within a twelve-hour period. Indeed, one researcher discovered to his supreme stupefaction that a nestling robin could, within a single day, gulp down some fourteen feet of earthworm! Small wonder the infants grow so fast. And small wonder that baby robins so frequently starve to death in the care of human foster parents who just don’t realize how quickly a nestling’s food metabolizes and must be replaced. The amount of food which parent robins collect for their babies over the entire two-week nestling period totals about three pounds. Surprisingly, this amount does not vary significantly with the number of youngsters in the nest; thus members of a two-baby brood get much more nourishment per baby than those in a brood consisting of four or five young.

In futile efforts to stuff their seemingly bottomless babies to the brim, both parents work feverishly from dawn to dusk. All day long each adult completes a shuttle between nest and lawn every five or ten minutes, although the mother may occasionally take time off to warm the youngsters by brooding (sitting over) them, an activity she also does throughout the night. Should one of the parents be killed by cat or car during this crucial period, the surviving partner faces a herculean though not impossible task in nourishing the ravenous infants. In those cases where the nestlings are still quite young (and hence unfeathered), the mother would have a better chance of successfully rearing the babies alone since the father would be unlikely to brood them sufficiently to avoid lethal chilling, especially during the night. One robin widower in Michigan, however, benefited from human intervention in the form of an ice-fisherman’s pocket-warmer that was securely fitted into the nest; his babies thus nice and warm, the male managed to feed and finally fledge two nestlings by himself.

In another case of one-parent rearing, a widowed mother raised her young despite a wing injury that precluded flight. Fortunately her nest rested on the first limb of a leaning tree and she could travel from ground to young by hopping up the Tower of Pisa trunk. Labor omnia vincit, you might say if you spoke Latin. Happily, the mother’s wing healed just as her nestlings fledged.

The type of food that the parents give their nestlings consists primarily of animal matter, for although robins are fond of fruits, most berries do not ripen until too late in the nesting season. In addition to earthworms, the babies are fed grubs, spiders, caterpillars, grasshoppers, beetles, and a host of other insects. While many of these animals are not antagonists of humanity, and some are indeed beneficial, a great number are noxious. And considering that a single pair of robins harvests three pounds of buggy crop in raising each of their two or three broods per summer, we can well appreciate the invaluable contribution that the species as a whole makes toward keeping insect populations in check. Robins, together with their fellow songbirds, truly constitute essential ballast in the balance of Nature.

The Mechanics of Feeding. Although parents may initially feed their newly hatched nestlings by regurgitating food that has already been partly digested, they soon deliver whole worms and insects into the nestlings’ gaping mouths. Seeming perhaps a rather simple process, parental feeding of the young instead represents a complex interchange of numerous behavioral signals.

During the initial six-day period of blindness, the infants reflexively respond to any jiggle of the nest (such as is caused by the parents when they land) with an immediate and vigorous stretch of the neck, an exigent opening of the mouth, and a series of clamorous calls that continue until food is received. Later, after their eyes have opened, the young expectantly emit this begging behavior upon the mere sight of their approaching but still-airborne parents. Begging may be even further elicited by a “dinner is served” call which the parents frequently emit as they arrive.

Just as the visible approach, jiggling landing, and dinnertime calls of the parents initiate “begs” from the babies, these begs in turn have a decided effect on parental behavior. In general, the tiny head held highest and the gaping mouth spread widest wins the worm. The goods are delivered with a deep thrust of the parent’s bill down into the bright orange-lined throat of the baby. This bright inner color of a nestling’s mouth is additional stimulation that encourages feeding by the parent; in other words, an orange gaping mouth may mechanically elicit bill-thrusting by robin parents in much the same way that a red breast seems to reflexively elicit aggression.

But the most important point to be inferred from the above discussion is that the parents—rather than following a strict rotational system in which each baby must await its turn—instead tend to feed the nestling who begs the most vigorously, even if that happens to be the same youngster who received food on the immediately preceding visit. Less vigorous nestmates, meanwhile, must await another parental trip. Clearly, this type of procedure favors the feeding of a brood’s biggest and strongest babies at the expense of any weakling who cannot lift its head as high. As a result, precious and hard-got nourishment is not wasted among infants who, perhaps because of some inborn defect that saps their strength, are destined to meet an early death regardless of parental care.

On the other hand, if all the babies are healthy and strong, no single one among them will manage to grab all of the handouts. This is because the magnitude of the begging behavior gradually declines as a baby grows less hungry. Thus, once a given youngster has obtained a meal, its begging upon the parents’ next visit will tend to be less intense than that of its still-hungry nestmates who will consequently be fed their due.

In summary, the formidable task of keeping a nestful of baby robins well-nourished involves an intricate exchange of behavioral signals between parents and infants. The parents, by their food calls, their landing on the nest, and their visible approach, elicit begging from the nestlings. In turn, this begging behavior—including neck stretching, mouth gaping (which displays the orange-lined throat), and begging calls—stimulates the parents to thrust into the inviting mouths whatever food they are carrying. The automatic and reflexive nature of this parental thrusting is blatantly revealed by the fact that even after dispensing a load of food, a parent sometimes rethrusts its now-empty bill down a baby’s throat if the greedy infant continues to beg.

Sanitation

The enormous appetite of a nestling robin quite naturally leads to a substantial solid waste problem. Indeed, nestlings defecate nearly as frequently as they eat. This presents a serious problem. Were robins unable or disinclined to keep their nests immaculate, harmful bacteria, parasites and flies would be constant menaces to the young. So the parents, most especially the mother, always practice scrupulous sanitation habits and never permit excrement to remain in the nest for long.

The excrement itself is voided by nestlings in neat white self-contained “fecal sacs.” The parents may actually eat these sacs with no ill aftereffects and indeed perhaps gaining a little nourishment. Or they may carry the sacs away after each visit so that an efficient regimen of food-delivery and waste-evacuation characterizes each nest trip. In this case, the sacs will be ferried some distance from the nest rather than simply tossed over its edge, since this latter practice would furnish a potential nest-location clue for any predator who spotted white splashes on the ground below.

The parents’ meticulousness also extends to other potentially pathogenetic material in the nest. Should one of the youngsters die, the mother will remove its body with sorrowed promptness. Occasionally in her rush to cleanse the cradle, she may toss out something of value. Once a robin dropped a sizable package into a camping area as she few overhead; upon inspection, the parcel proved to be a stunned nestling with a long piece of liver protruding from its bill. Apparently the mother—having found the liver in nearby trash—attempted to give the lengthy meal to her infant. The offering was more than the youngster could handle, and at her next visit the mother plucked up the loose unswallowed end with the intent to discard it, without realizing that she was throwing out her baby with the bath.

Protection

As threats to life, both predators and adverse weather are far more formidable after the young hatch as compared to before. Within their eggshells, robin embryos are assured the nearly continuous presence of their mother who discreetly incubates with quiet inconspicuousness. Squirrels, crows, jays and other potential enemies will have trouble first in locating the nest and then in overcoming the valiant defenses of the mother as well as her mate, who can be quickly summoned to the site by the female’s cries of alarm. Weatherwise, the eggs are almost always shielded by the sitting female from the harshness of too much heat, too much cold, or too much rain. All of this sharply contrasts with the situation of hatched robins. Now a bustle of activity envelops the nest, with both parents constantly coming and going as they strive to keep three or four noisy babies well fed. Obviously, such activity can easily attract the attention of predators; in addition, the chances that the young will be unprotected from either predators or harsh weather are increased.

Even humans—enormous creatures that we are—risk a quick, screaming blow to the forehead should we venture too close to a nestful of young. When one adds the further consideration that the calls of an alarmed parent bring not only his or her mate to the scene but often all other robins within earshot—each of whom is ready and eager to join in any justified fray—one can appreciate how safe nestlings really are in the presence of their parents.

Parental presence is also important in protecting nestlings against cool nights, hot suns and strong storms. After her young have hatched, the mother continues to spend each night on the nest to brood the infants with her warmth through the chilly darkness. The daytime may also be too cool, especially during early spring, and this becomes particularly dangerous since the mother is now compelled to help her mate find food for the nestlings and thus is hard-pressed to have time for brooding.

A much greater threat during the daytime, however, is the intense heat of the summer sun, particularly if the female has built her nest at an unshaded site. Very young nestlings will die within fifteen minutes if they are exposed to blistering heat without the shady protection of a brooding mother. On really hot days, the parents may repeatedly fly to a nearby stream or birdbath to fill their bills with cool water for their broiling babies. Nestlings, of course, are much more susceptible to injury from either heat or chill during the first few days after hatching, before insulating feathers have covered their bodies.

Even if the nights and days are moderate in temperature, nestlings need motherly protection during rainstorms. To be sure, the youngsters are quite capable of gripping the lining of their nest with surprising strength and are not so easily storm-swept from their little haven; indeed, tenacious nestlings have been known to cling to their nest even after the whole structure has been flung to the ground. Nevertheless, baby birds do need shelter from the rain itself, again especially if they are un-feathered. In one particularly picturesque description of robins shielding their young during a sudden summer downpour, an admiring observer wrote how a female and her mate

perched on opposite sides of the nest, breasts pressed together and heads crossed by each other, their bodies and wings thus sheltering the young like a pitched roof while the rain ran harmlessly off on both sides.

The singular sight of such selfless parental parasols must have been heart-warming indeed.

At Last, a Fledgling

By the time they are ten days old, robin nestlings are restlessly active throughout the day. In contrast to the passive between-meal dozing so characteristic of their earlier behavior, they now preen their feathers with persistence and stretch their wings with regularity. As they continually test their newly acquired growth, the three or four fidgety infants almost crowd their tiny nest to overflowing. And perhaps spurred by lack of elbow room as much as anything, the young birds begin to fledge.

Although the proper time for departing the nest is about thirteen days after hatching, nestlings often leave prematurely, especially if the nest is disturbed in any way. A person merely wandering too close can ignite a flapping explosion of plump and chirping cannonballs that scatter in every direction; if this early exodus is more than two or three days ahead of schedule, the youngsters are unlikely to survive. Under less pressing circumstances, the young normally leave their nest one at a time.

But whether fledging occurs under pressured duress or in the gradually emerging face of inevitability, no part of robin life is as exciting, dramatic, climactic or utterly clumsy as when young birds finally break away from the nest. With mottled breasts and stumpy tails, they dare to do something they’ve never done before—they dare to fly! Well, almost. Actually, it’s more like a fluttering, sputtering descent.

Like hesitant swimmers debating between abrupt entrance or gradual submergence into an icy pool, the youngsters squat on the edge of their nest or along a perch they’ve boldly hopped onto and look doubtfully down at the ground, which must seem so far below. Then, with a little coaxing from their parents, encouraged by their calls or enticed with some tasty tidbit, they hop into the air and instinctively flap with all their might. Still they lose altitude and soon kerplunk on the lawn below, for they cannot after all really fly. They’ve been fooled, they’ve been tricked, they’ve been duped; they are birds, yet cannot fly. “Am I a lousy penguin?” each one asks, perhaps.

Though unable—as they will be for the first few days—to sustain horizontal flight, fledglings can sputter diagonally twenty or thirty feet depending on the perch height from which they take off. Nevertheless, it is probably just as well that robin nests are usually built quite low. But though safe from injuries of impact, fledglings always face the nagging prospect that their first “fight” may inadvertently plop them into some unfortunate situation. Since robin nests often overhang streams or ponds, for example, the steerless youngsters occasionally wind up treading water on their maiden voyage. Imperiled by finny demons of the deep (not to mention drowning), the buoyant babies usually manage to flap across the water’s surface toward the horrified calls of their parents onshore. Once safely beached, the waterlogged infants sit panting, dogshaking, and no doubt wondering whether their overcrowded nest was really so bad after all.

Once the excitement of their first flight is behind them, most fledglings never return to the nest even though they remain in their parents’ territory for quite a while. Initially crouching in nestling fashion, the youngsters soon begin to stand erect in the proud manner of the independent adults. But independent they are not as yet, nor will they be for nearly two weeks after leaving the nest. Carefully tended by both parents for a day or so, the young birds are soon left entirely in the tutelage of the father. The mother, meanwhile, departs to build a new nest, lay new eggs, and hatch new nestlings: Thus as soon as the first brood’s two-week fledgling period is complete, the father must hurry back to his mate and help raise another batch of newly hatched babies.

Despite plenty of paternal protection, fledgling life is a pretty precarious period for robins, especially during the first week. And small wonder since the young birds fly only poorly, advertise their location through frequent food calls, and are often still slow to recognize potential danger. Through warning calls that send the fledglings hopping for cover, the ever-anxious fathers manage to handle many problems that arise. But occasionally the youngsters blunder into unusual predicaments that require more ingenious solutions, as the following story attests:

Madison, Wisc. Pedestrians were placing bets on a parent robin here, when it finally accomplished the task of freeing a young Robin which had slipped through a sidewalk grating in the business district. Lured by a fat worm waved by the parent, the little robin made a great effort and was free.

When not calling for food from bushes or staring dumbly into the playful face of a large tail-wagging dog (or less fortunately, into the hungry eyes of a stalking cat), fledglings hop around the lawn in the artful footsteps of their foraging father. Trailing a few yards behind, the babies bounce up to their parent as soon as the latter has procured some juicy morsel; then squatting, quivering their wings, calling plaintively and gaping their mouths, the youngsters are fed in true nestling tradition. Gradually over the two-week term of post-nestling education, the fledglings increasingly find food on their own. At first pecking randomly at the ground, the birds soon learn through trial and error to discriminate leaves and twigs from worms and beetles, although for a while many of the latter simply wiggle and waddle leisurely away from the clumsy hunters. As time passes, the father may try to hasten his offspring’s independence by ignoring more and more of their “feed me!” demands; but if inattention doesn’t work and he finally loses forbearance, the parent may resort to more immoderate action. One pop, for example,

apparently became impatient with the importunities of a helpless fluttering young one almost as large as himself, and seizing a piece of cotton that had lodged in a bush, stuffed it into the mouth of the youngster to keep it quiet.

Even after “weaning” is complete and the now-flying youngsters can find food for themselves, they often linger in their parents’ territory for another week or so before eventually dispersing outward. Though the rate of this dispersion varies from youngster to youngster—with some clinging to parental aprons much longer than others—the outward progress in general is rather slow. Indeed, nearly 60 percent of the young are still within half a mile of their birthplace some two months after leaving the nest. One factor affecting their dispersal is the pattern and extent of cover-providing foliage occurring in immediately outlying regions; dispersion is more rapid in the absence of suitable cover, since then the young birds must “hop over” wide open spaces before temporarily settling down. As they move out from their origins, the young often congregate in considerable numbers at particularly good feeding areas, such as ripening fruit patches. The resulting flocks, in which young robins may outnumber adults by ten to one, remain intact only so long as the food supply lasts.

In conclusion, we might characterize fledglinghood as an exciting period of robin life, a period in which young birds progress through a gauntlet of adolescent dangers as they journey from helpless newborns to self-reliant adults. It is a frantic period marked by fretful fathers who—whether scouring the lawn for worms and grubs or flitting through branches to warn and scold—do their darndest to guide inexperienced offspring through teenage traumas. And finally, when all lessons are learned and all tests passed, and the young birds can fend for themselves, fledglinghood climaxes a long series of wonderful natural events, events that began even before the deliberating female first selected a site for her muddy, grass-lined nest.

Not Just a Family Affair

Although rearing young is typically a private project, a task that each pair of robins usually undertake and complete entirely by themselves, other birds may occasionally contribute to the effort. Being territorial, the parents seldom allow other redbreasts near enough to the nest to participate in the care of eggs or nestlings. During the fledgling stage, however, nonparent robins can more readily become involved since the youngsters may then wander out of their parents’ territory and into that of their neighbors. Even when the bush-hiding babies do remain near their own nest, their loudly insistent food cries often entice nearby adults—whose own young may still be but eggs—to trespass with foody appeasements. Thus numerous instances have been reported of foster parents feeding, protecting and in general adopting strange fledglings who may or may not have been separated from their own parents.

Such incidents clearly demonstrate the powerful ability of a young robin to arouse, through its own infantile behavior, the parental instincts of unrelated adults. Interestingly, the adults don’t even have to be other robins, for cooperative parenthood can transgress interspecies boundaries as well. To cite but a few examples: a Mourning Dove once added her eggs to those in a robin’s nest, and then took turns incubating with the mother redbreast; Song Sparrows have been known to not only feed baby robins but to clean their nest as well; Eastern Bluebirds once defended a fledgling robin from Blue Jay attack; and two Northern Cardinals once dive-bombed a cat who held a fledgling robin in its mouth (under the awesome onslaught, the feline freed the frightened but otherwise unharmed youngster).

In another, more prolonged instance of cardinal-robin teamwork, pairs of both species began building their nests on the same tree in Reynoldsburg, Ohio. After a storm destroyed the cardinal nest, the redbirds not only helped their neighbors complete their nest, but even added their eggs to those of the robins in the hybrid structure. With the two mothers incubating in shifts and the fathers getting along equally well, one egg of each species eventually hatched. The four parents then worked in harmony to nourish the step-siblings-with the redbreasts dispensing worms in toto, and the redcrests regurgitating bugs au jus.

In short, then, numerous birds have been known to contribute to nearly every possible phase of robin familyhood—including nest construction, egg-laying and incubation, nestling-feeding and sanitation, and fledgling protection. There have also been complementary cases where robins have played the benevolent role of benefactor by helping to raise non-robin babies. Perhaps the most unusual instance involved a male who adopted a motherless baby chick. Now, chicks—unlike baby robins—are well developed when they hatch; within mere hours they are quite capable of pecking the ground for food and do not like having it crammed into their mouths the way robin nestlings do. Thus whenever the well-intentioned redbreast tried to give the fluffy youngster a worm via normal robin procedures (down the throat), the chick steadfastly refused the meal. Just as the male was about to abandon his seemingly futile efforts, however, he happened to drop the worm on the ground whereupon the chick promptly gobbled up the juicy tidbit. This fortuitous fumble apparently bridged the communication gap between these distantly related birds, because the robin then proceeded to toss worms and bugs at the feet of the hungry and thereafter receptive chick.

Before closing the present topic, we might note that some birds have other than honorable intentions when they participate in the robin’s family chores. Once, an English Sparrow developed the habit of perching on the edge of a robin’s nest whenever one of the parents appeared with an insect for the young; as the parent attempted to feed its nestlings, the sneaky sparrow snatched up the morsel instead. Fortunately, though this felony occurred frequently during the two-week nestling period, the persevering parents nevertheless managed to get sufficient nourishment into their victimized babies.

An interloper who more commonly threatens to take undue advantage of the robin’s parental instincts is the Brown-Headed Cowbird. The female cowbird apparently does not care for the trials and tribulations of motherhood, for she always lays her egg in an unguarded nest of another species with the hope that it will be incubated, hatched and reared by the foster parents when they return. This is at great cost to the foster species since their own eventual young maybe be given less care than if the cowbird nestling wasn’t there.

Robins, luckily, only rarely accept a cowbird’s egg in the first place. The robin’s own eggs are very obviously different from a cowbird egg in color (blue vs. white), size (the robin’s eggs are larger), and speckling (the robin’s eggs are typically unspeckled, unlike the cowbird’s). In fact, one reason why robin eggs are blue may be as an evolved defense against cowbird parasitism. Easily recognizing the cowbird egg as foreign, a robin may either puncture the uninvited ovum or indignantly eject it from the nest.

A robin’s annoyance at the cowbird’s deed will be even more manifest should the freeloading culprit be caught in the insidious act. In one reported case, a cowbird landed on a robin’s nest right after the incubating female had flown out of sight. The robin returned in time to interrupt the cowbird’s deposition, however, and she promptly attacked the latter with vengeful viciousness. Easily outweighing the intruder, the redbreast nastily knocked the cowbird to the ground and then spitefully struck her with wing and beak. After a full minute of such flogging the cowbird finally made her escape, though leaving blood stains and a warm egg on the grass behind her. In this classic clash of maternal instincts, robinhood had won.

A final frequent participant in the robin’s family affairs is the well-intentioned human who, coming upon an unattended nestful of babies or perhaps some solitary fledgling, assumes the role of the apparently lost parents. In most cases this is a mistake, for hand-rearing baby songbirds is an extremely difficult endeavor which often ends in failure. Likely as not, moreover, the parents were only temporarily absent when their offspring were “rescued.” Thus, unless circumstances clearly indicate otherwise, one should always presume that robin youngsters—no matter how abandoned they appear to be—are in fact receiving proper parental care. (Fledglings in particular possess a special knack for appearing woefully alone and abandoned even when they are not; desolation is indeed a guise they seem to rehearse.) Accordingly, robin youngsters in general should not be disturbed, and if they are inadvertently handled (for example, by children), they should be promptly returned to wherever they were found.

Occasionally, however, baby birds are obviously injured or orphaned, and human intervention offers their only chance for survival. If the youngsters are nestlings only a few days old, they will require considerable heat since newly hatched songbirds are initially unable to regulate their own body temperatures. Equally important, they must be fed quite often—as much as every ten to twenty minutes from dawn to dusk. Their diet should be varied and of a high-protein content; one recommended mixture includes freshly killed bugs (or perhaps bits of mealworm), wheat germ, turkey starter, gelatin, egg yolk (hard-boiled), dog food, applesauce, cottage cheese, strained carrots, and small amounts of cod liver oil and human baby vitamins. Little or no water should be given. Of course, older nestlings and fledglings—who can maintain their body temperatures and are able to consume much more food at each feeding—are far easier to nurse and much more likely to survive under human care.