On this visit, the young of one nest have gotten large and are squawking loudly; the nest below appears quiet. While I’m counting birds, a father heron flies in to the top nest and begins to regurgitate food for his three nestlings; mother is also with them. About the time Coronavirus was incubating in the US (Feb-March), this pair began fashioning their nest. I’m no Great Blue Heron expert, but from what I’ve learned on the web, males begin the building of nests in a rookery; these birds usually breed in colonies which may contain up to several hundred pairs. Isolated pair-breeding is rare, and this rookery has nowhere near hundreds of pairs. But it’s close to mom’s house in Clarksville where we’ve been sheltering in place, and easy to reach. Once a male chooses a nesting territory, he begins to “display” - to attract a female whom he then presents with nesting materials. The birds have “elaborate courtship and pair-bonding displays that include a ritualized greeting, stick transfers, and nest relief ceremony in which the birds erect their plumes and “clapper” their bill tips,” according to allaboutbirds.org |
It’s mid morning and the water is calm as I slowly paddle through the cove. I approach the swamp where land’s edge greets the furthest extent the water reaches. There are snags everywhere - tree stumps, branches and bushes in the water - making navigation in my inflatable kayak a bit dicey. The goal is to reach the heron rookery close enough so the birds aren’t spooked, yet close enough to get some photographs. I’ve got binoculars and let the kayak drift while I scope out the four nests, trying to count the young and adults. It’s difficult because if I glass too long on the nests, I can drift into a tree or branch. At one point, I nearly run into a partial heron carcass hanging from a bush - possibly the victim of an eagle attack! (A mature bald eagle flies over the cove as I paddle.) I’ve not witnessed this behavior but once paired together, the male gathers sticks for the female who weaves a platform and saucer-shaped nest cup lined with small twigs, bark strips, pine needles and moss. Nest building can take from three days up to two weeks. And the finished nest can range from a simple platform measuring 20 inches across to more elaborate structures used over multiple years, reaching four feet across and nearly 3.5 feet deep. These nests are typically high in the trees, 20-100 feet off the ground, like the ones I photographed. But a friend from Texas has watched herons nest near the ground which is more common in areas free of predators. Apparently Great Blue Heron parents both incubate the 3-5 eggs for 25-29 days; and they can have two broods a season. But next year, the herons will not return as a couple; they may choose different mates each year. I watch the three squawking nestlings scream for their father’s regurgitated offerings, then within minutes, he flies off the nest. Apparently both parents regurgitate food for their offspring, but this bond will only last for the nesting season. This particular day, there are four herons in the top nest, and another adult sitting on a branch about 20’ lower. Lower still is another nest with a parent and several babies much younger and smaller, making it hard to count. In the same tree is another nest which appears to be abandoned. Weeks ago there were nestlings and an adult on that nest, so I’m not sure if the young are nestled in the bottom while parents are hunting, or if the young were lost to predation. To the right of this tree, which houses three nests, is a nest in another tree obscured by branches. This nest is difficult to photograph in the clear because too many branches make it difficult to focus. But it holds two young and an adult. After counting the birds and photographing them for about twenty minutes, I paddle through the waterlogged low hanging tree limbs and out into the open part of the cove, managing to keep the inflatable boat seaworthy! Then I swing left, away from the main channel to check on some more nests, passing turtles sunning on logs. There’s a section of dense trees on my left, and I believe there are nests in there because I’ve seen birds fly into the trees squawking. But my goal is only a few minutes paddle towards a power line cut-out where I hang a left into a narrow channel that leads to more nests I’ve viewed before. Before I even see the nests, I hear the young squawking for food. There are at least four nests that I can see, and this morning they hold seven birds in this section of the rookery. Photographing the birds is a bit harder since there are more branches in the way. Also the angle from the water to the high spaces means I can’t get too close or I won’t see much of the birds in the deep nests. When born, young herons are able to vocalize immediately, but they can’t fly until they’re about 60 days old. At that time, they continue to return to the nest and are fed by the adults for another few weeks. So visiting the rookery should be a pastime for me for weeks to come. I’ve photographed blue herons in many different states on our RV odyssey, even in Canada and Amsterdam. A familiar bird, it’s the largest heron in North America with a six-foot wing span. One of the reasons I think they’re so common, is a variable diet which allows them to exploit a variety of habitats and to winter father north than most herons. They will eat fish, amphibians, reptiles, invertebrates, small mammals, and even other birds. In fact, last September when we were bear viewing in British Columbia, a fellow photographer filmed a heron spearing and eating a rat! The herons have a quick and sharp bill that they use to spear prey and long claws to help secure and tear large animals. I love watching them both stalk prey in shallow waters, or stand utterly still and wait for their prey to swim by. They grab smaller prey in their strong mandibles or use their dagger-like bills to impale larger fish, often shaking them to break or relax the sharp spines before gulping them down. In most places they seem to spook when humans get too close, but I have found in developed urban areas some become habituated to human presence and photographers can get close. The adult herons in Clarksville seem to spook when I’m around, or other photographers. But perhaps they are more accommodating to fishermen/women. There are other birds in the area to keep tabs on, bluebirds, Osprey, Eagles, vultures, cardinals, gold finches, Canada geese, and many more. I’m guessing the young heron nestlings I spotted back in April may be fledging soon, but I can’t know when they hatched. The ages do seem to vary of the eight nests I’ve seen, so I hope to study their behavior some more in coming weeks. I’ve had a hard time blogging during Coronavirus because it seems there aren’t many interesting topics to write about since I’m not on the road. But there is other wildlife nearby, and I have some hiking and outdoor activities I’m doing, so perhaps I’ll write another nature blog in a few weeks. Until then, if you want to know more about the habits of Great Blue Herons or other herons, I suggest you check out allaboutbirds.org or birdweb.org or audubon.org. Stay safe and well, and let me know of any heron sightings!
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AuthorFormer documentary film producer, wife and mother of one...I'm taking time off to see the US with my husband Terry. Here's where I'll write about our adventures RVing until the money runs out! Archives
August 2021
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