Feather Patterns and Protection from Predators???

[U_Stormcrow]

The only situation I have seen where coloration may help is with visually oriented predators and where the chicken is trying hide. Hens incubating there clutch of eggs out in the open is the first situation where she covers the clutch moving very little with the exception of blinking her eyes. The way the feathers cover her body it is very difficult to see her breathing. The next is where a chicken freezes because is sees a predator although this approach does not work once the predator makes the chicken out. The final approach is where a chicken that is pursued by a predator flattens itself out in a depression or forces its way into vegetation. All these situations involve the bird becoming very still.

I think there may be two different predators, and two different predation styles, in mind.

There are predators who are very alert to movement, but have very poor ability to distinguish colors. Against those, no amount of coloration is effective, because they are looking for change. They don't care what a thing looks like, only that the overall image is changing. Pattern *may* help, but not moving at all is FAR more effective.

The second is predators that hunt not based on movement, but on exception. We humans are that type of predator. Colors stand out, movement much less so. Against us and those like us, colors that blend in and patterns that break up the outline are very effective.

Against the first, we need birds of a certain behavior. Against the second, we need birds of a certain appearance.

Of course, its also possible i have fallen asleep to FAR too many nature shows. Rods and Cones, rods and cones.

 

[centrarchid]

Being a predator myself, I can detect motion or pattern although the second requires be to get on a search image. If a predator goes after lots of different types of prey items in a complex environment, then the motion detection may be easier.

The behavior the chickens exhibit can also involve a cultural component, at least with chickens I have.

 

[U_Stormcrow]

"Its Complicated" seems a fair assessment.

 

[centrarchid]

"Its Complicated" seems a fair assessment.

Only when trying to confuse the reader.

 

[U_Stormcrow]

The Human Predator

 

[raingarden]

The wild tyoe BBR/Red Junglefowl hen color evolved to camouflaged her when nesting or otherwise hiding. Then anthropogenic selective breeding worked hard to undo it all..

 

[centrarchid]

The wild tyoe BBR/Red Junglefowl hen color evolved to camouflaged her when nesting or otherwise hiding. Then anthropogenic selective breeding worked hard to undo it all..

I have a breed that has considerable variation in coloration and plasticity in behavior even with respect to predators, hence my previous reference to "culture" of the chickens. My focus at this point is on adult hen coloration. Only first image is of background setting where coloration becomes real important. Chick coloration is something else altogether.

Most are of this coloration or a little darker. It is similar to wildtype although a little lighter. She is further lightened by bleaching in sunlight.

Other variants although not complete representation.

Next three within 10 feet of each other during total eclipse.

American Dominique although I have had games with similar coloration.

 

[Folly's place]

Here we have had both bantam and standard chickens since 1992. Almost all our losses to raptors have been our millie fleur colored d'Uccles, small birds and easy for the hawks to carry off. Once an Australorp hen had (probable) injuries from a raptor, and very recently we had a white Chantie killed by a young Cooper's hawk, seen by a neighbor, in our spruce tree line.
Otherwise, a daytime fox attack killed ten nice hens, all colors. He seemed to pick actively laying hens, the only way they differed from the rest of the free ranging flock.
Our worst single event was when one of our own dogs escaped and killed 21 (!!!) birds of all sizes, bambambam, in about an hour. She is a rescue from a fighting dog background, so incredibly efficient. The survivors were individuals who got up in trees, or the coop rafters.
Watching chickens who are in danger, individual behavior varies, and not always in good ways for the predator involved. Crouching in place doesn't work unless the ground predator hasn't already located that individual, or doesn't smell the bird. Flying up into a tree may be a better choice, if the attacker can't climb. Against a raptor, flying is the wrong decision.
Our birds, especially if not raised by a wise broody hen, in a mixed age flock of survivors, are at a big disadvantage, until they survive and learn from bad experiences.
And flock owners also have a learning curve, making truly safe housing, especially at night, and when the flock can't free range because of external threats.
Mary

 

[centrarchid]

Here is one of my solid black hens. She would have to be on a really dark substrate or in the shadows to be hidden. I doubt any hawk would confuse her for a crow as her proportions are all off. The black coloration of most crows and ravens I think does not serve as a repellent against raptors. The raptors likely see a rainbow of colors when seeing what humans call black birds. The black feathers may be more durable or better for absorbing heat from sunlight for a bird that otherwise does not rely upon cryptic coloration.

 

[centrarchid]

To tackle this issue for real, people would have to report the number and proportions of birds representing color types before predation events and losses as a function of color type. The difference in proportions before and after losses is the information need to get beyond the endless anecdotal accounts that do not put this issue to rest.