06 January 2017

Roosters’ Crowing

When your rooster crows at the break of dawn
Look out your window and I’ll be gone…


Like the lyrics from Bob Dylan’s “Don’t Think Twice, It’s All Right,” I always thought roosters started crowing at or just before sunrise.


Some chickens behind the barn.
(Photo by Vicki)
Welcome back. As I mentioned in an earlier blog post, my father-in-law, a retired dairy farmer, is not fond of chickens, live or cooked (Save the Barn!). Nevertheless, he’s renting an unused barn and an adjacent field to his grandnephew, who with his wife and a partner are raising beef cattle and free-range chickens. (They also had a goat for a spell, but her penchant for hanging out in the cattle trough became too much of a problem.)

The first batch of chickens seemed to go reasonably well, and they’re now on a second batch. Whether intentional or not, this dozen or so has at least a couple of roosters, which, judging from the lack of crowing, the first batch didn’t. And it’s not just during the day. When I step out to do my predawn jogging and walking, I sometimes hear crowing.

Isn’t 3:30 AM a bit early for crowing? I was curious. Wouldn’t you be? OK, maybe not. Anyway, here’s what I learned.


Chickens and Me
I should mention that I have no experience with chickens. When I was growing up, there was a small chicken farm nearby, though I was never inside. There was also Chi-Chi, a neighbor’s pet rooster. I only saw him from a distance and not when he chased our dog Lassie (Time for Pets--Dogs).

The closest I’ve come to chickens was in Puerto Rico, when I was working at the Arecibo Observatory in the mid-1960s. I would occasionally see a hen or two hunting and pecking in peoples’ yards, but once, I did go to the cockfights at a local gallera (cockpit). Watching the men handling the birds, strapping on the spurs and especially betting was much more interesting than watching the cocks fighting.


Cockfight action at Gallera La Paloma, Guaynabo, Puerto Rico, 2013. (Photo from video: www.youtube.com/watch?v=ppn6ppU6vcA)
Cockfighting in Puerto Rico dates back to the 18th century and is regulated under the Department of Recreation and Sports. The island’s nearly 130 galleras are listed under the U.S. National Register of Historic Places. A 2012 government report noted that, annually, over one million people attended cockfights, generating over $100 million in bets, admission, food and other expenses.

Crowing Research
Searching online, I didn’t find a long list of research reports on the topic (hmmm…I wonder why). A few years ago, however, researchers from Japan’s Nagoya University did take on the challenge.

They conducted a series of well-designed experiments with caged roosters in light- and sound-controlled environments, monitoring the birds under 24 hour continuous dim light; split 12 hour light–12 hour dim light; different intensities of external light stimuli; and different amplitudes of external sound stimuli (other roosters crowing).

The study found that crowing was driven by the roosters' circadian rhythm, their biological clocks. (Circadian rhythms, you’ll recall, are internal changes that generally track a 24-hour cycle, responding primarily to light and darkness.) External stimuli, such as light and crowing by other roosters, induce roosters to crow, but that crowing is also influenced by a circadian clock.

Wrap Up
In keeping with circadian rhythm, roosters might start crowing as early as two hours before sunrise. The birds in the barn could be confused by external lighting. Just past the edge of the field, there’s a church parking lot with a bright light that’s on all night (see first photo, left-center). It’s also natural for roosters to alert the hens if predators are out and about. I doubt that’s the case, yet fox, coyote and even a wolf have been seen in our area.

There’s also the possibility that one of the birds crows because he just feels like crowing. Don’t you get that way sometimes? Thanks for stopping by.

P.S.
Research report on rooster crowing in Current Biology journal:
www.cell.com/current-biology/fulltext/S0960-9822(13)00186-3
Article on the study in National Geographic: news.nationalgeographic.com/news/2013/03/130318-rooster-crow-circadian-clock-science/
Puerto Rico galleras: www.nps.gov/nr/feature/places/64501213.htm (see link to full file)
Example article on roosters crowing in the middle of the night: animals.mom.me/mean-roosters-crow-middle-night-6686.html
Note: The Chinese Year of the Rooster begins 28 Jan 2017.

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