Why is she doing this????

[peeps7]

It isn't scratch grains, they get corn, sweet feed, etc.

 

[Tuffoldhen]

Agrees with Jody, that is considered scratch grains and not good for chickens on a daily basis.....They need a poultry feed that includes proteins and nutrients....corn and sweet feed are not good and are candy to chickens...

 

[SpottedCrow]

those high strung Mediterranean breeds are a pain in the butt with picking. Obelisk does this too, if she's got to stay in for extended periods.
Get them on a good healthy layer feed and supplement with cat food and she should be better.