Perch width, what’s the science?

[centrarchid]

When I go out and place my finger between breast and roost, there is either a very small gap or the pressure is extremely low. Some birds looked at are so habituated to my handling they remain asleep even as I probe. I assume asleep when head remains tucked in feathers over wing.

Some body with a broody hen needs to reach under to determine if the hens are curling their feet when brood patch contacts clutch. My memory of that has hens flat footed even when crouching.

 

[centrarchid]

This idea is occupying too much of my energy. I have several groups of chickens where each has several roosting options. Yet observations I am making muddy waters. Locations appears to override everything unless they are roosting out in those darn trees where owl makes that counter productive.

Tonight I will release about 70 chickens and allow them to stay on roost until just after dark where we will have to stay out with flashlite to keep owl at bay. As chickens are policed up I will document the following: bird size / age, roost shape, roost size, roost height, and location.

Darn you shadrach.

 

[Shadrach]

I would offer to come over and help but it's a long long way from here.

 

[centrarchid]

My kids will be drafted to help. They like doing such. I having difficulty figuring how information generated will be useful for backyard chicken keepers. The tree roosting birds that are clearly exercising the most choice have a suite of factors they consider that have nothing in common with birds not roosting in trees. Our coops and barns have factors that totally override particulars of roost dimensions and shape.

 

[pipdzipdnreadytogo]

I've misunderstood the nature of the tendon locking mechanism then. I had taken it to be a robotic/mechanical mechanism that required a particular leg position to unlock.
How is the friction added? Does the chicken have control over the position, or texture of these rough patches?
I have looked at various explanations but I haven't found anything that explains at sufficient depth.

Consider how hard it would be to 'unlock' those joints if it really did lock into place in a mechanical / robotic way, though. That doesn't really make biological sense to have a mechanism like that, particularly in such a vital body part. Adding friction does make sense, as it may take a little more energy to move those parts when 'locked' into place, but in the grand scheme, that extra energy to move when in the 'locked' position is probably negligible overall. Especially considering that it likely doesn't happen often that they move around when in that position, and that the mechanism also relieves some of the energy used to hold those joints in place when they aren't moving around, so it probably balances out. BUT, this is just extrapolation on my part from what I know from physics and biology, so take it for what you will.

Friction is added through the 'rough patches' along the tendons. It's like (in an extreme case) rubbing together two pieces of sandpaper compared to rubbing together two pieces of regular paper. The sandpaper has a lot more friction and it's harder to rub those pieces together than it is with regular paper, which is smooth and slides relatively easily across another sheet of paper. I would assume by the fact that it develops fetally and before mechanical motion could play a role in their development that these rough patches are always in the same general location along the tendon and of the same 'roughness'.

Some body with a broody hen needs to reach under to determine if the hens are curling their feet when brood patch contacts clutch. My memory of that has hens flat footed even when crouching.

From my experience, their feet are flat when on the nest, both when brooding and when simply there to lay an egg. As I said, those rough patches exist, but they don't override the bird's control of her muscles and ability to move her feet.

 

[centrarchid]

From my experience, their feet are flat when on the nest, both when brooding and when simply there to lay an egg. As I said, those rough patches exist, but they don't override the bird's control of her muscles and ability to move her feet.

Means two people recall same.

 

[Shadrach]

Means two people recall same.

Make that three.

 

[centrarchid]

I just let out about 60 birds. More to be released later. I doubt if more than 15 will use roost they have not been using when confined. My approach is not going to work. Somehow penned flocks will have to have manipulated roost and location must be controlled for, somehow. This is going to be a hard thing to test on side of choice.

 

[Shadrach]

Consider how hard it would be to 'unlock' those joints if it really did lock into place in a mechanical / robotic way, though. That doesn't really make biological sense to have a mechanism like that, particularly in such a vital body part. Adding friction does make sense, as it may take a little more energy to move those parts when 'locked' into place, but in the grand scheme, that extra energy to move when in the 'locked' position is probably negligible overall. Especially considering that it likely doesn't happen often that they move around when in that position, and that the mechanism also relieves some of the energy used to hold those joints in place when they aren't moving around, so it probably balances out. BUT, this is just extrapolation on my part from what I know from physics and biology, so take it for what you will.

Friction is added through the 'rough patches' along the tendons. It's like (in an extreme case) rubbing together two pieces of sandpaper compared to rubbing together two pieces of regular paper. The sandpaper has a lot more friction and it's harder to rub those pieces together than it is with regular paper, which is smooth and slides relatively easily across another sheet of paper. I would assume by the fact that it develops fetally and before mechanical motion could play a role in their development that these rough patches are always in the same general location along the tendon and of the same 'roughness'.






From my experience, their feet are flat when on the nest, both when brooding and when simply there to lay an egg. As I said, those rough patches exist, but they don't override the bird's control of her muscles and ability to move her feet.

Thank you for taking the time to reply.
I think I need to look at some literature on the subject.
I did wonder about the mechanical lock, but I don't know, so I have to think about the various explanations and work out what seems reasonable.
It's an interesting ability; the chickens, not my thinking.

 

[centrarchid]

Handling chickens and song birds a lot and even some raptors, the mechanism in chickens is not a well developed, especially in relation to weight of birds. Chickens are much easier to dislodge from roosts even when rigidity of roost is factored in.