173

The first egg of this five-egg clutch was laid! Eggs are usually laid in the morning.

The clutch consists of five eggs. On average, six eggs are laid in tree swallow clutches. However, these birds can lay as few as three to four eggs, and as many as nine in a single clutch! The female bird will incubate the eggs for about fourteen days. 

A piece of tissue paper was found built inside of the nest. Birds use soft substances, such as goose, crane and duck feathers (as shown in this nest), to keep their eggs safe and warm. Unfortunately, garbage is also occasionally used in the nest if it is found by the parents, and could pose a hazard if it is able to make the birds sick. Otherwise, the nest will likely remain unchanged for the next week or so.

So many exciting things have happened to this box today!

First, the male tree swallow was spotted on top of the nest, and the female was found inside. The male birds have deep teal to somewhat muted royal blue coloration, which is usually a little bit brighter than the females' plumage. Female tree swallows generally have a greener plumage.

However, this female tree swallow has an exception to the common plumage. Note the brown coloration on the head and wing feathers. She is a second-year female, which means that she is experiencing her second year of life, which also explains her dull coloration. This means that this is her very first nest of chicks! Fascinatingly, mama bird was banded last year as a young chick in a box not too far away from box 173! Bands are numbered cuffs of metal or plastic with a number code on them. Wherever in the world that this bird is caught, the band can be read and traced to where it was banded. This means that she could have migrated all the way down to Central America for the winter, and returned to almost the exact same area that she grew up in!

We guarentee that a bird is female by checking for a brood patch. This is a section of the bird's belly that loses feathers during the early days of their breeding season so that the mama bird can envelope her eggs in her feathers, as well as put her warm body on them, during incubation. This helps to insulate the eggs and keep them warm!

The two parents of the nest were banded! Adult birds get banded when the chicks are between 1-4 days old. This is because the birds must go inside the box to feed the teeny tiny chicks inside. In order to catch the birds, they must go inside the box so that we can easily grab them without them escaping. This does not harm the chicks or the adult birds, as we keep our hands free of chemicals while we handle the birds, and the parents become fiercely protective of their young once the eggs hatch, so we do not worry about abandonment. Despite this statement, please continue to leave the boxes alone and check this website out instead! This practice keeps the birds comfortable and safe, and protects you from illnesses and injuries.

The chicks have been banded! Chicks can be banded at as early as nine days old, and as late as thirteen days old! These chicks in particular are eleven days old. Past thirteen days old, the chicks are preparing to fledge, or leave the nest. They usually fledge at sixteen days, but disturbing them past the thirteen day mark may make them fledge too early, which makes them easy prey for predators such as foxes, ermines, cats, and other small carnivores. However, most nests do not fledge at sixteen days old here in Alaska.

Tree swallow chicks are almost always much fatter and heavier than their parents. This is because the parents are stuffing the chicks' faces with food all day long instead of feeding themselves. However, they are definitely not capable of flight just yet. Right now, they're reminiscent of young chickens! We take almost all of the same measurements on the chicks that we would take on the adults. However, we do not check the lengths of the longest primary feathers on the adults, but we check that on the babies because their feathers are very tiny. They can easily be measured with calipers.