Sunday, February 01, 2009

A trio of leggy redheads

These three sandhill cranes like kids. I think they're the same ones who "persuaded" Hugh's son to empty his seed bag for them a week ago. This Friday, they hurried to meet us on the pathway, in hopes of more goodies.


Two of the three, looking for a handout.

Yesterday, I wrote that they were youngsters. Later, I began to wonder; don't the red heads mean that they are adults? Time to do a bit of homework.

Amazing how one question leads to another; I ended up with pages of notes on Grus canadense, or Sandhills.

Sandhill chicks, called "colts" (because they're leggy, like young horses?), are reddish brown, with grey underparts. By maturity, they have turned grey, except for the forehead, which is bright red. During breeding season, they smear themselves with red mud, maybe for camouflage purposes; by the end of the season, they are ragged and worn.

So these three are adults, not breeding yet. The adolescents, once the parents have chased them away in order to start a new brood, wander around aimlessly, "hanging out" with their peer group. Somewhere between 2 and 7 years old, they pair off, then stay with their mates year-round, often for life. The lifespan in the wild is about 25 years.


Practicing the dance steps.

Male and female sandhills look alike. (To human eyes, anyhow. They seem to know the difference.)

When the time comes, the adults put on their makeup, and go to the dance. One will start dancing, and the prospective mate will imitate him. Soon, the other sandhills in the group join in until the whole flock is "on the floor".
"Five courtship displays have been identified as part of "dancing," the primary mechanism of pair formation in this species. These displays are the Upright wing stretch, Horizontal head pump, Bow, Vertical leap and Vertical toss. Three courtship displays are used exclusively by paired adults to maintain the pair bond and synchronize reproductive development. These are the Bill up, Copulation and Unison call displays."
From Animal Diversity Web
I've never seen this. Maybe this year, I hope.


Wing stretch; full wingspan, about 6 feet.

Breeding starts, for migratory birds, in April or May. Sandhills resident year-round, like some of the Reifel Island birds, may start earlier, even in mid-winter. Two eggs are laid, in large (2 -3 ft. wide) nests on small, low islands with a good view, in May or June, and hatch a month later. (Which is about the time that Laurie tried to sidle past a protective adult on the trail, and was stabbed for it.)

Both parents incubate the eggs and care for the chicks, with the male doing most of the guarding, while the female sits. The colts leave the nest, at least for the days, a day or two after hatching. They are soon able to feed themselves. At ten weeks, they begin to fly.

We've seen these youngsters, standing ankle-deep in mud, probing for food, while the adults stood guard on the banks.

For this nesting and family-raising endeavour, the sandhill crane pairs claim a territory of an average of 40 to 60 acres, although if conditions are favourable, it may be as small as 3 productive acres. The Reifel Island sanctuary covers 890 acres; room enough for at least 20 families.


Contemplating a possible snack.

What do sandhill cranes eat? Anything. Insects, seeds, frogs, mice and other rodents, plants, fish, snails, snakes, roots, berries, grass, other birds, birds' eggs, ... And the contents of kids' bags and buckets. They'll have your sandwich, too, if you're still carrying it, thank you. After we and the bucket lady emptied our containers for the trio, they followed us down the trail hoping for more.

I was surprised to find, on a discussion board (Hancock Wildlife Channel), a local resident who feeds sandhills out of his hand. And he has the photos to prove it. Brave! I don't think I would have steady enough nerves. Those beaks look dangerous enough, but the eye ... !


Armed and ready. With his eye on you.

One other tidbit:
"Fossil evidence found in Nebraska indicates that sandhill cranes have been around, unchanged, for about 10 million years. That makes them the oldest-known surviving bird species in North America." From The Georgia Straight
Wikipedia clarifies:
"A 10-million-year-old crane fossil from Nebraska is often cited as being of this species, but this is more likely from a prehistoric relative or the direct ancestor of the Sandhill Crane and may not belong in the genus Grus. The oldest unequivocal Sandhill Crane fossil is "just" 2.5 million years old, over one and a half times older than the earliest remains of most living species of birds, which are primarily found from after the Pliocene/Pleistocene boundary some 1.8 million years ago."
2.5 or 10, whichever; that eye does look dinosaurish.

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Some of the sources for this post:
Wikipedia, The Georgia Straight, NationMaster Encyclopedia, Bird Web (Seattle Audubon Society), US Dept. of the Interior, Animal Diversity Web, Hancock Wildlife Channel, Baker Sanctuary, and Rock, Paper, Lizard.
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4 comments:

  1. Anonymous7:16 am

    some day I would love to see these Redheads like this! Bravo job!

    ReplyDelete
  2. Great post. You are fortunate to have sandhills around to watch. I love the way they move their legs while walking.

    ReplyDelete
  3. Yes, I'm sure those are the same ruffian birds. I recognize that orange eye!

    Thanks for the link.

    ReplyDelete
  4. Monarch; you will. I'm sure of it.

    Vickie; interesting comment. I'll pay more attention to the legs next time I see them.

    Hugh; You're welcome.

    So we're one step closer to crossing paths.

    ReplyDelete

I'm having to moderate all comments because Blogger seems to have a problem notifying me. Sorry about that. I will review them several times daily, though, until this issue is fixed.

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