Sunday, June 16, 2013

Distraction Displays by Ovenbirds & More

The Ovenbird - looks like a thrush, but belongs to the warbler clan
It's not unusual this time of year to come upon a particularly visible Ovenbird. Often enough this species can be difficult to observe; however, come the breeding season, Ovenbirds become very protective of their nests and young and will come out of hiding with the smallest provocation. All it takes is for someone to come too close to their unseen nests or to their fledged young and they will be scolded with volleys of sharp warning calls. Sometimes both parents will pace back and forth on an open branch, calling and nervously twitching side to side. That is of course interesting behavior, but it doesn't qualify as a distraction display.
An Ovenbird parents gives sharp "smack calls" to warn off potential predators
The Ovenbird's nest - said to resemble a Dutch  oven - built on the ground with a roof over it 
The female Ovenbird incubating eggs in her cave-like nest
The other day in the old woods I came upon a male Ovenbird that was definitely upset by my presence. He did some of the expected scolding, but mostly he engaged in a distraction display. He ran in a wide circle around me –evidently trying to draw me away from his unseen nest and/or young. Periodically as he ran he would relax his pace, spread his tail,  drop it to the ground and then take a few quick steps. Sometimes he would augment his performance by partially spreading his wing feathers and allowing them to droop. The aim of his display was to create the impression that he was injured and would therefore be an easy target for a predator or for an intruder that was otherwise bound to discover his nest.
The male briefly Ovenbird sings from the forest floor
The distraction displays begins with intermittent tail dragging
Note the spread tail feathers and slightly drooping wings
He fearlessly walks up close to me
A fledgling Ovenbird perched on a low branch in the forest understory
Though I've seen other birds perform similar distraction displays, I don’t recall having seen the Ovenbird's version. I'm much more familiar with the type put on by the Ruffed Grouse and the Killdeer. They most often feign mortal injuries - reel around on the ground or limp about pathetically. The mother grouse will also sometimes emit shrill alarm calls that make it sound like she’s in agony. However, given the opportunity, not every species that is known for giving distraction displays will perform one. I've had just as many grouse mothers simply fly off into the brush and allow their young chicks to rely on their own camouflage and their abilities to remain motionless until the danger passes.

Killdeer are famous for their flamboyant distraction displays
A mother Ruffed Grouse staggering around with tail spread and neck feathers "ruffed" out
Once I had a hen turkey engage in a kind of distraction display right in front of me. It consisted of her fearlessly running in circles around me, while clucking madly. I was definitely distracted by her, and I never did see any of the poults that she was protcting. One other time, I inadvertently startled a turkey hen whose reaction was to explosively take flight and abandon her clutch. The young poults, which were probably only a few days old, all instinctively played dead. 10 of them were strewn about the grassy trail –motionless and looking like victims of a bloodless massacre. Their cryptic plumage did much to hide them, but for sure, the effect would've worked better in taller grass. As I was leaving, they began to make high pitch distress calls and soon the hen returned to collect them.
A very young turkey "poult" tries to disappear in the weeds
They remained absolutely motionless until I moved well away
A couple of years ago I apparently got too close to the nest of a Hooded Warbler. The female Hooded performed a distraction display quite similar to that put on by the Ovenbird; she ran about in front of me, dragging her tail and trying her best to lure me away from her unseen nest. Again, this is another species that is not generally known for these kind of distraction displays and indeed in my many years of observing Hooded Warblers on their nesting grounds, this was the only one that ever behaved in that manner.
The male Hooded Warbler issuing alarm calls near his nest
The female Hooded alarm call watching over her recently fledged brood

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