The Wood Thrush is a medium-sized North American songbird found across much of the eastern and central United States and parts of southeast Canada. Wood Thrushes are shy, elusive birds that inhabit deciduous and mixed forests. They have a beautiful, flute-like song that rings through the trees in summer.
Wood Thrushes build open cup nests on horizontal tree branches, hidden amongst the leaves. The female lays 3-5 pale blue eggs, which she incubates for 12-14 days. The hatchlings are altricial, which means they are born helpless, with closed eyes, no down, and rely completely on their parents for food and care.
So what does a baby Wood Thrush look like when it first hatches? Let’s take a closer look at the appearance and development of these songbirds through their early stages.
Appearance at Hatching
Wood Thrush hatchlings are tiny, weighing only about 8 grams at birth. Their bodies are pink and sparsely covered with gray down feathers. Their eyes are closed and they have no feathers on their heads.
Hatchlings have bright yellow corners on their wide gapes. This is to help guide the parents to their mouths when feeding. Their feet already have small claws which will help them cling to branches as they grow.
Overall, newborn Wood Thrushes are helpless, featherless creatures that don’t resemble their parents very much yet. But they grow and develop quickly under the constant care and feeding of their parents.
Changes in the First Week
In the first week after hatching, baby Wood Thrushes go through some major changes as they start growing feathers.
By day 2, pinfeathers start breaking through the skin on the hatchlings’ wings. These feathers still have a protective sheath, but it soon splits open to reveal gray feather shafts.
By day 5, the wings and body are covered with gray downy barbs. The barbs will soon separate into soft fluffy down. True flight feathers start to emerge from the wings.
The hatchlings’ eyes begin opening by day 6 or 7, revealing dark gray irises. But their vision will be blurry at first.
So in just a few days, naked and helpless hatchlings transform into fuzzy nestlings covered in down, with emerging wing feathers and open eyes. But they still rely completely on parental care.
Developments in the Second Week
In the second week after hatching, baby Wood Thrushes become more alert and active in the nest. Their feathers grow rapidly, aided by the protein-rich diet supplied by the parents.
By day 8, the nestlings have sprouted their first real feathers on their wings, back, and head. The body is fully covered in gray downy feathers. The eyes are wide open and head is more erect.
By day 12, the wood thrush nestling is an odd mix of adult and baby features. The wings and back are covered in flight feathers, but the head is still rounded and downy. The tail is just a stub.
At 2 weeks old, the nestlings can sit up in the nest and lift their heads high when parents arrive with food. Their appetites are voracious as their bodies experience rapid growth.
Third Week Onwards
By the third week after hatching, baby Wood Thrushes look much more mature. Their juvenile plumage resembles the red-brown coloring of the adults.
The body is fully feathered, with just some lingering downy tufts around the head. The wings are nearly adult size and the tail is about half grown.
At this stage, the nestlings are very active, frequently stretching and flapping their wings to build flight muscles. They can stand, lift their tail, and preen developing feathers.
By days 16-17 some precocious youngsters may fledge and leave the nest briefly before returning. But most Wood Thrush fledglings leave the nest for good around 18-20 days after hatching.
Even after leaving the nest, the fledglings cannot fly well or forage independently. They follow and beg food from their parents for several weeks as they hone their flight skills and learn to find food.
Identifying Features
So what are the best ways to identify baby and juvenile Wood Thrushes? Here are some key features:
- Size: Hatchlings are tiny, about size of ping pong ball. Nestlings grow rapidly, reaching adult size by time they fledge.
- Shape: Round body and oversized heads and feet. Become more slender and proportional by fledging.
- Feathers: Bare pink skin at hatching. Gray down by first week. Juvenile plumage similar to adults.
- Gape: Bright yellow corners obvious when begging for food.
- Eyes: Closed at hatching. Open and clear by 1 week old.
- Behaviors: Sitting in nest early on. Begging, wing exercises, and increased activity in later weeks.
The following table summarizes the growth timeline of baby Wood Thrushes in the first 3 weeks after hatching:
Age | Size | Feathering | Eyes | Behaviors |
---|---|---|---|---|
Hatchling | 8g, ping pong ball size | Bare pink skin, few down tufts | Closed | Movements limited to slight gaping of mouth |
1 week | About 20g | Covered in gray down | Open by day 7 | Sit upright in nest |
2 weeks | 50-60g | Gray down and flight feathers | Eyes fully open | Move actively in nest, beg loudly |
3 weeks | Adult size | Juvenile plumage | Clear vision | Flap wings, may fledge |
Parental Care
Baby Wood Thrushes are dependent on their parents for warmth, protection, food, and care in the first few weeks after hatching.
The female alone incubates the eggs, while both parents feed and brood the hatchlings. Nestlings beg loudly for food with their yellow gapes wide open. Parents deliver a diet of insects and berries directly to the nest.
Even after fledging, the inexperienced juveniles cannot find food on their own. The parents continue bringing them easy to digest meals as they learn survival skills. Parental care tapers off around 4 weeks old.
Wood Thrush pairs demonstrate devotion and teamwork in raising their young. Both take turns shading the nest on hot days and warning of predators. The nestlings thrive under this attentive care during their rapid development.
Conclusion
Baby Wood Thrushes undergo a remarkable transformation from helpless hatchlings to fully feathered fledglings ready to leave the nest in just 3 short weeks. Key changes include:
- Rapid feather growth, starting with gray down then juvenile plumage
- Eyes opening by first week and clear vision by two weeks
- Increasing activity in nest and loud begging
- Fledging once able to fly short distances
With intensive parental care and a protein-rich diet, Wood Thrush nestlings grow from naked and blind hatchlings to adept juveniles ready to learn independence. Their rapid development prepares them to thrive and add their voices to the forest chorus.