Peter Goodfellow's book "Avian Architecture," reviewed here several days ago, goes on my shelf alongside two others also dealing with nests, and also among my favorites. The first is "Built By Animals." Author Mike Hansell covers a wider variety of animal constructions ranging from caddis flies to weaver birds to termites, and on to animals clever enough to make and use tools.
He notes that the weaver birds building nests similar to those of our orioles. The weaver birds use spiral binding, half-hitches, simple overhand knots, and slipknots to anchor the strands used to weave a nest. Oriole nests hang from small, extended tree branches. The nest is securely attached to the branch or branches at several points, lengths of plant fiber wrapped around the branch holding the nest sack securely in place. It is built to expand as the birds hatch and grow. I've watched orioles build nests, but only finishing stages. What I want to see is the bird work on the initial and perhaps biggest challenge: attaching the first strand of grass to the branch. It is most likely wrapped around and around, the bird manipulating the fiber with bill and feet.
Both Barn Swallows and Cliff Swallows use mud in nest construction. They collect mud pellets, each building an adobe-type nest of a different style. Author Hansell points out that mud is not mud. Each species uses mud of a different consistency, chosen to meet differing needs.
"Built by Animals" was published by Oxford University Press in 2007. It is available in soft cover.
The third book is "Egg and Nest" by Rosamond Purcell, Linnea S. Hall, and Rene Corado. This is essentially a book of portraits of bird eggs and nests taken from the collection of the Western Foundation of Vertebrate Zoology. The eggs, particularly those marked for camouflage, are works of art, the nests no less so. Take the information gathered from the first two books, and then page through this one. Birds are amazing. "Egg and Nest" was published by Harvard University Press in 2008.
Here are photos of three previously owned nests. The first is the mud and grass cup built by American Robins. Look closely at the top right nest edge. See the piece of wire the bird used as nesting material. The second nest was built by Baltimore Orioles. The third nest, builder unknown, shows another example of grass strands used to anchor the nest to tree branches. The strands hanging from the near side of the nest have broken loose.
