Great Egret and Snowy Egret
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BirdWalk Newsletter 11.5.2017 Magnolia Plantation and Gardens Walks Conducted by Perry Nugent Newsletter Written by Jayne J. Matney “Great Egret Preening” Cover Photo by Guenter Weber _________________________ Great Egret (Ardea alba) Snowy Egret (Egreeta thula) Two of the more common wading birds here in South Carolina, the Great Egret and the Snowy Egret are white, slender birds you many find walking along the banks of the marsh or swamp. Other white birds which appear to be quite similar, the Cattle Egret and the immature Little Blue Heron, may be found in the area as well, so be careful identifying them. The Great Egret is the largest in size, all white, and has black legs and feet and yellow-orange bills. The Snowy Egret, in comparison is also all white, but smaller than the Great Egret. The Snowy Egret has black legs like the Great Egret. However, unlike the Great Egret, the Snowy Egret has black legs with yellow feet. They look as though they are walking around with little yellow slippers. Both have long, slim legs and necks. During flight, those long necks crimp in as an s-shape, and the legs extend out straight. Unlike the Great Egret’s yellow- orange bill, the Snowy has a black bill. During breeding season, the Great Egret’s lores, skin area between the bill and the eyes, becomes bright green. Notice the change of beak and lore color in the below photo taken by John Nickerson. The Snowy Egret’s lores become bright yellow to red. Both birds show wispy feathers called “aigrettes” on the head, nape, and the lower neck to chest area. They use these fanciful feathers to attract their mates by spreading them out in an elaborate display. These two species have many other things in common. Back in the 1800’s, their feathers were prized for fashion purposes and the birds’ populations dropped dramatically. After conservation efforts, both species are now very common within their ranges. They prefer to be in marshland and swamp habitats, but will expand to lake shores and mangroves- as long as water and a viable food source are available. If the areas are isolated such as barrier islands, they will claim a rookery there. They thrive on fish, frogs, crustaceans, polychete worms, and other aquatic animals. The Snowy Egret is most active while pursuing food. They have been observed hopping, running, and walking along banks snatching up creatures or spearing them with their beaks. The Great Egret is a bit more dignified in their hunting methodology. Slowly perusing the shallow waters, the egrets will stir up animals in the mud or herd animals in the shallows. They may opt to stand still and patiently wait for fish to come within striking distance. In an attempt to fool any perspective prey, both egret types have been known to try to blend in by slowly swaying their neck and head as the breeze softly stirs the marsh grasses. Both types will stay in mixed flocks while foraging and nesting. When it is breeding time, the males choose the location and start displaying for the female. Note the egret in the photo below, by Jo Frkovich, displaying the beautiful breeding plumes. He may hold his head up-beak to the sky. He may bow or bob his head. They have also been known to conduct aerial dances as they plunge toward the ground. Eventually, a female chooses him and they begin building a nest. Usually the process for building includes the male gathering the materials while the female does the design. For both species, both parents incubate pale greenish blue eggs, and both parents help with the care of the young. Nest predators include local raccoons, snakes, owls, hawks, alligators, and crows. Another major contention for egrets today is the loss and destruction of habitat. In conjunction with that, run-off from fertilizers and pesticides from farmlands, and run-off from sewage treatment are contributors of this destruction of healthy habitat. Different sources indicate increases in range for the Great Egret populations. However, they differ in which side of the range, north or south, are showing the declines. Canadian numbers are showing a decline according to the North American Breeding Bird Survey from 1966 to 2014. However, in the Audubon literature, indications are made that the southern population counts are in decline. Snowy Egret numbers appear to be stable within their range. Here, you can see the difference between the immature Little Blue Heron (left) and the Snowy Egret (right). They do like to nest and forage in mixed flocks. The snowy will breed with Little Blue Herons to make hybrid offspring. Photo by Marina Coppedge. Information gathered for this article came from: “Great Egret”, All About Birds, The Cornell Lab of Ornithology; “Snowy Egret”, All About Birds, The Cornell Lab of Ornithology; Kaufman, Kenn, “Snowy Egret”, Audubon Field Guide; Kaufman, Kenn, “Great Egret”, Audubon Field Guide; Snowy Egret (Egretta thula), Neotropical Birds Online, Cornell Lab of Ornithology Fun Facts: • When Snowy Egrets take turns incubating the eggs, they play “pass the stick” literally, to indicate it is time for them to switch roles. This is their version of “passing the baton”. • In the 1800’s, when egret numbers plummeted, the feathers were valued at $32 per ounce- twice the value of gold per ounce at the time! No wonder they were being hunted so vigorously! • Snowy Egrets have been known to mate with other heron types such as tricolor Heron, Little Blue Heron, and Cattle Egrets and produce hybrid individuals. • The Great Egret is the national symbol for the National Audubon Society. This organization is the oldest environmental organizations in North America. The adoption of the Great Egret was very appropriate due to the fact that the organization was first formed specifically to stop birds from being killed for their feathers. • If conditions are tough, herons and egrets are very aggressive and competitive in the nest with their siblings. At times during low food source or poor environmental conditions, these birds will actually kill weaker, smaller siblings in order to survive themselves. This survival practice is called “siblicide”. • The oldest known Great Egret was 22 years and 10 months old. Great Egret parent and babies Photo by Guenter Weber __________________________________________________________________ “Our avian brothers are back to roost on the first leg of their annual sojourn south. Why them and not us? Maybe it’s because we humans are meant to be rooted in one spot.” Mitchell Burgess Northern Exposure 1992 __________________________________________________________________ 7 people investigated the avian populations on Sunday. 47 species were counted. Being an overcast day, the weather was not the best, but the birding was excellent. The bird watchers saw a few varieties of birds while in the front parking lot at the beginning of the trek. Two Red-eyed Vireos, a Blue Jay, a Blue- gray Gnatcatcher, a Hermit Thrush, and a Brown Thrasher made themselves known immediately. Later, near the cabins, another Hermit Thrush was seen. Viewed around the cabins were White-eyed Vireo, Red-winged Blackbird, and Common Grackle. At Riverwood Pond, Wood Duck, Gadwall, Blue- winged Teal, Green-winged Teal, Pied-billed Grebe, Anhinga, Great Egret, Wood Stork, Black-and-white Warbler with food and Common Moorhen were present. Photo by Guenter Weber Additional birds found in the Audubon Swamp were Little Blue Heron, Common Moorhen, and a lone Black-and-white Warbler. A highlight of the tour this week was seeing the Blue-headed Vireo along the Oak Grove trail. In the woodpecker family, the Red-headed Woodpecker, Downy Woodpecker, Pileated Woodpecker, Yellow-bellied Sapsucker, and Northern Flicker were identified. Also scattered around the property were Eastern Phoebe, American Crow, Carolina Chickadee, Carolina Wren, Ruby-crowned Kinglet, Eastern Bluebird, and Yellow-rumped Warbler. One Bald Eagle was perched in the “favorite eagle lookout tree” across from the boat dock. Near the house lawn, a Red-tailed Hawk spied on the visiting guests. A Pine Warbler was also seen in that area. As the walkers approached the maze, a Palm Warbler came into view. Double Crested Cormorant flew over with 26 birds in the “V” flight formation. Rounding out the list of birds were Mourning Dove, Tree Swallow, American Robin, Northern Mockingbird, Northern Cardinal, Red-shouldered Hawk, Black Vulture, Turkey Vulture, and White Ibis. “I hope you love birds too. It is economical. It saves going to heaven.” Emily Dickinson Yellow-rumped Warbler or “Butter-butt” Photo by Marina Coppedge Note the yellow patch on the top of the base of the tail, and the yellow side patch near the wing. .