Starlings can be excluded from entering nestboxes boxes by using the correct size entrance hole, but will out-compete bluebirds for woodpecker holes and other natural nesting cavities.During the summer, bluebirds feed mainly on insects. In the winter, they depend on wild berries.
1. (Geological Science) (of sedimentary rock, etc) composed of fragments of pre-existing rock that have been transported some distance from their points of origin. 2. (Biology) biology dividing into parts: a clastic cell. 3. (Medicine) able to be dismantled for study or observation: a clastic model of the brain.
Nonclastic Sedimentary Rocks. Nonclastic sedimentary rocks form from chemical reactions, chiefly in the ocean. Nonclastic and clastic sedimentary rocks are the only members of the rock family that contain fossils as well as indicators of the climate that was present when the rock was formed. Nonclastic sedimentary rocks are named according to the mineral present.