Tree Swallow Timeline

For the first few days after hatching, the chicks are at their most helpless. They have large closed eyes, soft pink skin, and no coordination. Throughout the first couple of days, they begin to grow a small fuzzy layer as their skin becomes grayer in patches. At this time both of the parents must go in and out of the box feeding the chicks, and so it ti the ideal time to catch the parents and record information on them.

The chicks have large yellow mouths called "gapes" that make it easier for the parents to feed the chicks in the dark nests. They continue to grow out their feather tracts, giving them a slightly spiny appearance. 

Getting larger by the day, the chicks have become almost completely grey on their backs. Pin feathers start to breach the skin, and they start to open their eyes. At around six days, the young are more able to flip themselves over.

Small feathers begin to break on the wings, making them appear bigger. White feathers pop out on the dorsal, and the bird is mostly fuzzy. The chicks' eyes are open and alert, and they begin to show fear behavior. 

At this point, the chicks begin to chirp and stand on their feet. The feathers have become more separated in the wings. The legs also become more scaly to the touch. At this age the chicks can reach up and take food from parents without the parents havign to go all the way into the box, and so it is usually hard to hatch the parents at this age or older. 

The chicks begin to perch, and are far more coordinated and alert. After day twelve, the chicks are not checked on in their boxes. If they are disturbed, they can fledge prematurely, which is extremely dangerous. Once out of their nests, the chicks won't go back in, making them easy prey. At 11 days old, the chicks are banded and have measurements taken on them. This does not hurt the birds, and helps future studies because it allows researchers to know which birds are coming back to Creamer's Field. 

At this age it becomes dangerous to open the nesting box or interfere with it in any way because it can cause the chicks to fledge out of their boxes before they are ready to survive on their own. They can not fly yet, but can flap their wings enough to be able to move around. This is when they start being able to sit up on the hole of the box looking out.

At this age the chicks look just like their parents with the exception of their color being brown instead of blue, and the fact that the chicks still have their gape, the yellow "lips" on the side of their beak. Day 16 is the youngest that chicks will fledge on, although they almost never do.

At this age it is common for all of the chicks to be leaving the nest. Usually some chicks will leave before the others, and sometimes there will be only 1 or 2 chicks left in each nest box at this age. 

At this age the yellow gape is drying up and getting less noticeable. If the chicks are still in the nest at this age, the parents may stop feeding them as a way to get the chicks to fledge.