Tricolored Heron

Published by the Smithsonian Institution between the 1920s and the 1950s, the Bent life history series of monographs provide an often colorful description of the birds of North America. Arthur Cleveland Bent was the lead author for the series. The Bent series is a great resource and often includes quotes from early American Ornithologists, including Audubon, Townsend, Wilson, Sutton and many others.

Bent Life History for the Tricolored Heron – the common name and sub-species reflect the nomenclature in use at the time the description was written.

My first morning in Florida gave me many delightful surprises and some charming new acquaintances. I had been wandering through a fascinating old hammock admiring the picturesque live oaks, with their festoons of Spanish moss, the stately cabbage palmettos, so suggestive of the Tropics, and here and there a Spanish bayonet in full bloom, shedding its fragrance from a pyramid of white blossoms; the thickets of saw palmettos, the various orchids and air plants on the old trees were all new and interesting to me. Finally I came to a little, muddy pool in an open glade and sat down behind some saw palmettos to watch a little flock of yellowlegs feeding in the pool. A passing shadow caused me to look up and there on silent wings a larger bird was sailing down to alight in the pool, my first glimpse of a Louisiana heron at short range. It was totally unaware of my presence and within a few feet of me. Soon another came and then another, until there were five of them. What beautiful, dainty creatures they were, their slender forms clothed in bluish gray, blended drabs, purples, and white, with their little white plumes as a nuptial head dress. How agile and graceful they were as they darted about in pursuit of their prey. With what elegance and yet with what precision every movement was made. For harmony in colors and for grace in motion this little heron has few rivals. I could have watched and admired them for hours, but the rattle of a dry leaf, as I moved, ended my reverie, for they were gone. But I shall never forget my first impression of this elegant “lady of the waters.”

Court8hip: In its courtship this dainty little heron is most attractive; though it lacks the wealth of glorious white plumes displayed by the American and snowy egrets, and though it can not throw out the bristling array of plumage shown by the reddish egret, still it has a grace of action and beauty of plumage peculiar to itself. Perched on the topmost bough of some low tree or bush, the male bowu to his mate, his long slender form swaying in the breeze, bending in long graceful curves and yielding to the pressure of the wind, as if he were a part of the tree itself. Like a “reed shaken by the wind” he bends, but does not break; and he never loses his balance. And now he dances along from branch to branch toward his mate, bowing and courtesying, with wings half spread. Many are the pretty attitudes that he assumes, with many graceful curves of his long slender neck. The plumes on his back are raised and lowered, like a filmy veil of ecru drab, and the pure white head plumes are raised and spread like a fan, in striking contrast to the blue and drab. It is a picture of irresistible beauty; his mate finally yields and the conjugal pact is sealed right there on the tree tops, without loss of poise.

Behavior, similar to that seen in courtship, is indulged in by the Louisiana heron, and by other herons, all through the nesting period, as a form of greeting between mates, in the ceremony of nest relief, and when approaching the young to feed them. Prof. Julian S. Huxley, who has made a special study of such sexual behavior, has sent me a number of photographs illustrating it and some very full notes on it, based on his observations made at Edward A. Melihenny’s preserve at Avery Island, Louisiana. I quote from his notes, substantially in his own words, as follows:

Migration is spread over a long period; some birds arrive at Avery Island early in March, the bulk come in mid-April and others not until May. On first arrival and for some time after, the birds are in flocks; mating then takes place (out on the feeding grounds, according to reports). The mated pairs no longer join the flock at its roosting place; but they jointly select a nest site. They may change their minds once or twice, but eventually, before building, they spend several days in a regular honeymoon. During most of this time they sit side by side, with one resting its head against the other’s flanks. Now and again a special ceremony, which I have not seen at other times, is indulged in; with loud cries the birds face each other and lean their necks forward, partly or wholly intertwining them, each feverishly nibbllng at the other’s aigrettes.

One or the other appears to be on the nest site continuously. When one has been away feeding and returns to the other, a second type of ceremony occurs; this may be called the greeting ceremony and is the commonest seen in the species. In both birds (typically) the crest, neck feathers, and aigrettes are raised, the head is somewhat thrown up, revealing the patch of buff on the chin, the wings are spread and a special cry is uttered as the returning bird alights and walks through the branches to its mate. This, ilke most other ceremonies of the species, is a mutual one.

Nest building soon starts. It is my experience that the male usually, perhaps always, finds the sticks for the nest, and brings and gives them to the fema]~, who then does the actual building. The giving of each stick is accompanied by a greeting ceremony.

After incubation has started, both birds take turns at sitting. The times of relief are somewhat irregular, though it appears that there are usually about four changes in the 24 hours, and that the female usually sits at night. Each time a nest relief occurs, there is normally a greeting ceremony, the attitude being kept up all the time the birds are changing places. This, however, does not close the performance. Almost invariably the bird which has been relieved goes and fetches one or (almost always) several sticks, which it presents to the sitting bird. The presentation is made in the greeting attitude. The sitting bird then builds the stick into the nest. I have seen as many as 11 sticks presented after one nest relief. The last one or two presentations are often characterized by a lower degree of emotional tension, as revealed in the degree of feather raising. Nest relief and stick bringing continue after the young are hatched and presumably until they leave the nest.

Another ceremony, which is much less commonly seen, appears to be performed by the male alone. In this the bird droops its wings, erects its neck vertically and its head almost so and gives vent to a groaning sound.

While brooding the bird often digs the angle of the wing into the contour feathers of the body, so that it is covered by a regular flap of these. If the bird is now slightly alarmed, it may stand up without opening its wings. This must push the flaps forward, for they then stand out at right angles to the body like epaulettes. So far as I could see, these epaulettes were never used in any display, although they were striking and gave the bird a bizarre appearance.

Nesting: I have seen many breeding rookeries of Louisiana herons and have spent many pleasant hours studying them, for they are by far the most abundant of all the southern herons. My first experience with them was in the extonsive marshes of the upper St. Johns River in Florida. Here we found, on April 18, 19, and 20, 1902, some large colonies breeding on the willow islands in this great morass, which we could reach only by poling a skiff through many acres of dense, aquatic vegetation. These little islands were thickly covered with small willows, averaging about 12 or 15 feet high. In some cases the Louisiana herons nested in colonies by themselves, but in other cases they were associated with a few water turkeys, snowy egrets, many little blue herons, and a pair or two of yellow-crowned night herons. The Louisiana herons far outnumbered all the other species and occupied the central portions of the rookeries. Their nests were built in the willows in every available spot and at every height from 2 to 12 feet above the ground, often several nests in the same tree; they were neatly and well made of small sticks and smoothly lined with fine twigs. Most of the nests contained four or five eggs and one held six. There were no young at that date.

In Monroe County we found the Louisiana herons everywnere abundant, breeding in all the inland rookeries, as well as on many of the mangrove keys. At the Cuthbert rookery they formed at least half of the colony, where we estimated that there were about 2,000 of them. Their nests were found everywhere, all through the rookery, but they were especially abundant in the interior, often 4 or 5 and sometimes 10 nests in a tree; most of them were from 6 to 12 feet from the ground in the black and red mangroves, a few being in the buttonwoods. At the time of our visit, on May 1,1903, fully three-quarters of the nests held young birds of various ages. The nests were small, irregular in shape, and loosely built of small sticks, but well lined with twigs.

On many of the islands off the coast of Louisiana we found breeding colonies of these herons. Most of the young had hatched and many had flown away when I was there late in June, 1910; but Captain Sprinkle told me that, earlier in the season, he had estimated that the largest colonies contained from 500 to 1,000 birds. One small colony, of about 50 pairs, still had eggs on Battledore Island. They were nesting in a row of low, black mangrove bushes which grew around the borders of a small marsh. The nests were from 2 to 5 feet above the ground. The mangroves were covered with white blossoms, among which the herons made a pretty picture. And all around them were populous colonies of laughing gulls, black skimmers, Caspian, royal, Forster, and common terns; it was a great collection of noisy neighbors.

Along the coast of Texas, in 1923, we visited a number of colonies in which Louisiana herons were breeding and in which this species usually predominated, but in all cases two or more other species were breeding with them. On Yingt-une Island, in East Galveston Bay, described under the snowy egret, we found a colony which, we estimated, contained about 800 Louisiana herons, 400 snowy egrets, and 150 black-crowned night herons. The Louisiana herons’ nests were mainly in the tall canes which bordered the marsh, though many of them were in the small huisache trees and bushes, as well as in the prickly pear cacti. Some of the nests were on or close to the ground and others were at varying heights up to 6 feet. Besides the usual nests of sticks, there were many nests made wholly or in part of the dead and dry stems of the canes; fine strips or bits of cane were generally in use as nest hrnngs.

One of the largest two rookeries seen was at Wolf Point, in Karankaua Bay, at the lower end of Matagorda Bay, which we visited on May 10, 1923. This was a densely populated rookery, on dry land, in a thick growth of willows, husiache, and other small trees, with dense thickets of thorny underbrush. The bulk of the population consisted of Louisiana herons, which arose in a great cloud as I entered; there were certainly several thousand of them. Among them were several hundred snowy egrets, a few pairs of reddish egrets and 15 or 20 pairs each of Ward and black-crowned night herons. Two or three pairs of black vultures were living in the rookery and the place was fairly alive with countless thousands of great-tailed grackles.

The other big rookery, visited two days later, was on Roses Point in La Yaca Bay. It was also on high dry land and was so well hidden in an extensive forest of mesquite and huisache that it took us sometime to find it. It was fully as large and perhaps much larger, as it was difficult to outline its limits. Besides several thousand, perhaps many thousand, Louisania herons, there were many snowy egrets, Ward, and black-crowned night herons, and some few reddish egrets. And, last but not least, I have never seen greattailed grackles so thick as they were here; they fairly swarmed everywhere and the trees were full of their nests, sometimes scores of nests in a single tree. The herons’ nests were mostly well up toward the tops of the trees, from 10 to 15 feet from the ground.

In the rookeries on the chain of islands, between San Antonio and Mesquite Bays, Louisiana herons were nesting abundantly among the reddish egrets and snowy egrets, in low bushes, 1 or 2 feet high, in the rank herbage and almost on the ground. On Big Bird Island, in Laguna Madre, they nested in a small colony by themselves in a tract of tall weeds. Here they had well made nests of dry weed stalks, straws, and grasses.

C. J. Pennock, under the name of John Williams (1918), describes an interesting colony, which he found near St. Marks, Florida, as follows:

In preparing to leave the island in a row boat, a landing was made across a small cove from the line of bushes that had formerly been used as nesting sites by these birds. On stepping ashore I was startled at seeing hundreds of Loujal~na herons spring up from the open, treeless marsh and immediately settle down again as I sank to cover. A few steps into the thick matted rushes and again the birds arose on hurried wing beats almost directly upwards and drifted with much croaking farther down the island. A few steps more and I was in the midst of a nesting colony of these birds; every few yards a nest directly on the depressed rushes where a high tide had beaten down the tops of the tnll rank growth. A hurried estimate of the number of these birds made approximately 500 individuals, but whether both sexes were in the marsh I could not determine, and no accurate count of the nests was attempted, asthey extended to a considerable distance in at least two directions: just how far was not discovered: and an enumeration under the condition would have required more time than could be spared then, but enough was seen to convince me there were more than 150 nestp, while there might have been two or three times that number. The nests contained from one to five eggs, but for the most part four, as far as examined all were freshly laid. The nests were but little more than the scratching aside of the tangled rushes and a few broken pieces of the same laid crossing one another to aid in retaining the eggs from working down.

Eggs: The Louisiana heron usually lays four or five eggs, sometimes only three, occasionally six or very rarely seven. In shape they vary from ovate or oval to elliptical ovate or elliptical oval. The shell is smooth, not glossy. The color is pale bluish green, varying from pale Niagara green” to “lichen green.

The measurements of 41 eggs average 44.1 by 32.3 millimeters; the eggs showing the four extremes measure 50 by 33, 48 by 34, 40.8 by 32, 44 by 30.6 millimeters.

Young: Audubon (1840) gives the incubation period as 21 days. Both sexes incubate the eggs and guard the young; from the time that the nesting site is chosen until the young leave the nest one of the parents is always on duty. As one walks through a rookery it is easy to locate the nests containing young by their plaintive peeping notes. The young remain in the nests until they are half or twothirds grown, probably longer if not disturbed; at this age or older they are easily frightened and readily leave the nest, climbing with great agility over the surrounding branches. They are quite expert at climbing, though apparently awkward, and can cling quite tenaciously with bill, wings, or feet. They sometimes fall, however; if they fall into the water they can swim quite well and may be able to reach their nests again; but occasionally they become entangled in the branches, or in the sticks of the nests, which usually proves fatal, as their parents do not seem able to help them in such situations; we saw a number of their dead bodies hanging where they were caught. The young are fed by regurgitation, after the manner of other herons, as long as they remain in or about the nests, and probably longer, until they learn to shift for themselves.

Plumages : The downy young Louisiana heron is distinctively colored, quite unlike any of the others. The top of the head is covered with long hairlike plumes, nearly an inch long, shading from “army brown” basally to “fawn color” and “vinaceous fawn” terminally; the back is clothed in long, soft down, “fuscous” to hair brown” in color; the under parts are scantily covered with ecarse, white down; the bill, feet, and naked skin are light green, yellowish in the lightest parts of the bill and feet.

The juvenal plumage appears first on the back which is soon well feathered, then on the head, neck, and under parts, followed by the wings and lastly the tail; the flight feathers are not fully out until the young bird is fully grown. In full juvenal plumage, the head and neck are deep “chestnut” or bright “bay”; the throat, a narrow stripe down the front of the neck and the underparts are white; the mantle, wings, and tail are “dark Quaker drab,” with “chestnut” tips on all the wing coverts, and more or less “chestnut” on the back. This plumage is worn through the winter with little change, except that bluish gray feathers gradually replace the brown ones and a partial prenuptial molt produces, by February or March, a plumage which somewhat resembles that of the winter adult; the white has increased on the underparts and there is more white and brown in the throat stripe; rudimentary plumes and long feathers have appeared on the back; but considerable chestnut still remains in the neck, shoulders, and lesser wing coverts; and the juvenal wings, with their chestnut edgings, have not been molted.

A complete postnuptial molt occurs during the following summer and fall after which the young bird is practically indistinguishable from the adult, at an age of 15 or 16 months.

Adults have a complete postnuptial molt in summer and early fall and a partial prenuptial molt in February and March, which does not include the flight feathers. The special adornments of the nuptial plumage are the long white head plumes, which form a part of the nuptial display and are lacking in the fall; but the “purpledrab” or “vinaceous purple” head plumes, the long feathers of the same colors on the neck, breast, and shoulders, and the “cinnamondrab” back plumes are all much more highly developed in the spring than in the fall, though all but the white head plumes are present in fall adults to a limited extent.

Professor Huxley says, in his notes:

Although the sexes are qualitatively similar, it is my experience that there is normally a quantitive difference between the birds of each pair, in respect of brilliance and epiganlic structures, the male having the brighter colors and the longer crest and aigrettes. In spite of this, the best adorned females are considerably above the level of the least brilliant males. This implies that assortive mating must occur, so that a well adorned male tends to mate with a well adorned female, and vice versa.

Food: The Louisiana heron seeks its food to some extent in the shallow bays and estuaries along the coast, but more often around the shores of ponds, marshes, rice fields, and fresh-water meadows. It seldom stands and waits for its prey, but prefers to pursue it more actively. Stealing quietly along, with cautious and measured steps, its quick eye detects the presence of a school of minnows; then crouching low, with head drawn in, it takes a few rapid steps, its sharp beak darts swiftly outward and downward with unerring aim; sometimes it misses but often two or three of the small fry are oaught before the school escapes. Its movements are so graceful, so swift and so accurate that it is a pleasure to watch them. Audubon (1840) has described its feeding habits very prettily, as follows:

See, it has spied a small fly lurking on a blade of grass, it silently runs a few steps, and with the sharp point of its bill it has already secured the prey. The minnow just escaped from the pursuit of some larger fish has almost rushed upon the beach for safety; but the quick eye of the heron has observed its motions, and in an instant it is swallowed alive. Among the herbage yet dripping with the dew the beautiful bird picks its steps. Not a snail can escape its keen search, and as it moves around the muddy pooi, it secures each water lizard that occurs. Now the sun’s rays have dried up the dews, the flowers begin to droop, the woodland choristers have ended their morning concert, and like them, the heron, fatigued with its exertions, seeks a place of repose under the boughs of the nearest bush, where it may in safety await the coolness of the evening.

He also says:

The food of this species consists of small fry, water insects, worms, slugs, and snails, as well as leeches, tadpoles, and aquatic lizards.

Oscar E. Baynard (1912) found in the stomach of an adult Lou isiana heron the remains of about 200 grasshoppers; and he reported that 50 meals of young birds accounted for 2,876 grasshoppers, 8 small frogs, 17 cutworms, 6 lizards, and 67 small crawfish. Although this species probably eats more fish than the other small herons, its other food habits make it decidedly useful.

Behavior: When starting to fly, this, and all the other herons, hold the neck extended in a long curve, with the legs dangling below but, when well under way the head is drawn in between the shoulders and the feet are extended behind to serve as a rudder. The wing strokes are deliberate, but steady and the flight is direct and strong. The morning and evening flights between roosting and feeding places are often made in loose flocks or long straggling lines, sometimes at a considerable height when traveling long distances. The white underparts serve as a good recognition mark. The graceful and elegant carriage of this heron has been referred to above. Quite a variety of croaking notes and squawks, some in soft conversational tones and some loud and vehement, are heard in the rookeries. Although it is more quarrelsome than the other small herons, it seems to get along well with its neighbors. However, I once saw a Louisiana heron alight on a little blue heron’s nest and deliberately poke the eggs out of it onto the ground; no resistance was offered, as the owner was absent. The pilfering of sticks from the nests of others is a cornmon occurrence in the rookeries, which often leads to a quarrel.

An interesting hiding pose, which suggests the usefulness of the stripe of brown, black, and white markings on the throat and neck of this and some other species of herons and bitterns, is thus described by William Palmer (1909):

The following interesting experience occurred in Florida. I had been walking among the pines with my gun and had slowly approached the backwater of the Kissimmee River where the water had overflowed the short grass well back of the usual shore line. Here I soon noticed a Loulsana heron standing in a few inches of water near a small clump of scrub palmettoes and at once conceived the idea of trying to find out how near I could get to the bird. Using the clump as a blind I gradually moved to within about 60 feet. Waiting a while to notice the bird and to allay its fears, for it had evidently detected me, I sat down on the grass and slowly worked myself to one side of the clump in full view of the heron and not over 40 feet away. Here I sat for some time lounging, first on one side and then on the other, at the same time working myself gradually nearer to the water, the heron all the time standing upright and immobile with its breast toward me, the neck upstretched and the bill pointed skyward. I could plainly see the irides, but the bird, now about 25 feet off, stood absolutely still for perhaps 20 minutes until I arose and then it flew off.

Professor Huxley says in his notes:

The flight games of this species are interesting. They seem to he indulged in only when the birds have arrived over the nesting pond when flying back from the feeding grounds. They fly in at a steady rate, 100 or 200 feet up, and, when over the roosting place, they fold their wings and drop or volpiane down. During the descent the aigrettes fly out like a comet’s tail. Some birds volpiane steadily down; others fall more rapidly and must skid from side to side before alighting, when thousands are thus performing at once, the sight is a very striking one.

Enemies: Plume hunters have made no effort to hunt this species, as it has no marketable plumes: its plumes might have come on the market, if the demand had continued after the supply of white aigrettes had become exhausted. Many young birds and some oldcr birds have been killed for food. There is, however, a human enemy, unconscious perhaps of his evil deeds, who causes considerable havoc whenever he indulges in his supposedly harmless sport in a heron rookery; and that is the bird photographer, who sets up his blind in a rookery and keeps the herons off their nests, often for long periods. I remember that, after we had spent parts of three days photographing birds in the great Cuthbert rookery, we left it in a sadly depleted condition. The crows and vultures had cleaned out practically all the nests anywhere near our blinds; the roseate spoonbills and American egrets had been completely broken up and driven away; hundreds of nests of the smaller herons had been robbed; and the ground was strewn with broken egg shells all over the rookery. The egg collector, who is constantly moving about in plain sight, frightens the crows away, as well as the herons, and is there fore much less destructive than the bird photographer. The safest time to practice bird photography, and the best time too to get good results, is when the young are partially grown, when there are no eggs for the crows to steal and when the young are too large for the vultures to swallow. Probably, when riot disturbed by human beings, the herons’ nests are constantly guarded by one of each pair. Otherwise, it is hard to conceive how many birds can be raised successfully, where fish crows are as common as they are in Florida or where great-tailed grackles abound as they do in Texas.

DISTRIBUTION
Range: Southern and eastern United States, Central America, the West Indies, and northern South America.

Breeding range: North to Lower California (Margarita Island and La Paz); Sinaloa (Mazatlan); Texas (Brownsville, Corpus Christi, Galveston, and Houston); Louisiana (Black Bayou, Jackson, and Lake St. John); Mississippi (near Natchez, Rodney, and probably Biloxi); Alabama (Petit Bois Island and Autaugaville); Florida (Tab lahassee); and Virginia (formerly Clarkesville). East to North Carolina (Orton Lake, formerly Beaufort); South Carolina (Washoe Preserve on the Santee River, Charleston, and Frogmore); Georgia (Savannah, Darien, Blackbeard Island, and St. Marys); Florida (St. Augustine, Mosquito Inlet, and Titusville); Bahama Islands (Great Abaco, Berry Islands, New Providence, San Salvador, Mariguana, and North, Grand, and East Caicos Islands); Porto Rico; and probably the Islands off the coast of Venezuela (Aruba and Bonaire). South to probably the coast of Venezuela (Aruba and Bonaire); and Panama (Rio Sabana and Lion Hill). West to Nicaragua (San Juan del Sur and Momotombo); Oaxaca (Tehuantepec); Colima (Colima and Manzanillo); Tepic (Las Pen as Islands); Sinaloa (Mazatlan); and Lower California (San Jose Island, La Paz, and Margarita Island).

Winter range: North to Lower California (La Paz); Sinaloa (Mazatlan); rarely New Mexico (Gila River); Tamaulipas (Matamoros); rarely Louisiana (Vermilion Bay); Mississippi (Biloxi); and South Carolina (Charleston). East to South Carolina (Charleston); Georgia (Savannah and Darien); Florida (St. Augustine, Mosquito Inlet, and Titusville); the Bahama Islands (San Salvador and the Caicos Islands);’ and probably other islands of the West Indies. South probably to the Lesser Antilles; the northern coast of South America and Panama (Rio Indio). West to Guerrero (Acapulco); Jalisco (Goatlan); Sinaloa (Mazatlan); and Lower California (La Paz).

Migration: The Louisiana heron is only partially migratory as it winters plentifully as far north as South Carolina. On the coast of Louisiana and Texas, however, it is only seen there rarely at this season. It has been noted commonly at Breton Island reservation, Louisiana, on February 3 (1914); and at Corpus Christi, Texas, late in March, 1878. At the Breton Island reservation it was common at times until November 10 (1913).

Casual records: The Louisiana heron apparently is not much given to postnuptial northward wanderings, as it has not been many times detected north of its usual summer range. It has been recorded from California (La Punta, January 17, 1914, and San Diego Bay, March 22, 1925); Arizona (near Fort Verde, September 24, 1884); northeastern Texas (Texarkana); Missouri (Clark County, April 13, 1890); Kentucky (Franklin County, about July 15, 1917); Indiana (Knox County, summer of 1894, and Starke County, June 26, 1876); Virginia (Cobb’s Island near Washington, D. C., August 25, 1922); New Jersey (Cape May, August 1, 1920); New York (Patchogue, summer of 1836); and Manitoba (Nettley Lake, 40 miles north of Winnipeg, September 7, 1924).

Egg dates: Florida: 57 records, December 8 to June 26; 29 records, April 7 to 26. Louisiana: 10 records, April 9 to June 21. Texas: 21 records, April 21 to June 22; 11 records, April 27 to May 16.