When you think of a newborn chick, do you think of the naked songbird calling for its parent or the fluffy little chick? Both are very different and show that perhaps not all birds are born with feathers as we expect.
Bird species are either altricial or precocial, determining whether their young hatch with or without feathers. Precocial species such as chickens, geese, and ducks are born with feathers. Most songbirds are altricial and rely on their parents for food. There are five levels to determine how precocial a species is.
The short answer here is that it depends on the bird species. Sometimes, you will see birds born naked and helpless that develop feathers with time. In others, you will see birds that are much further developed at the hatching time, with many feathers already in place. These chicks are either altricial or precocial, and the difference between them has a lot to do with their location, behaviors, and threats to their survival.
Altricial Birds (No feathers)
Let’s begin with the first stereotypical image of the naked songbird chick with its eyes closed in a nest. These birds are altricial. They still require time to develop to gain their sight, strength, and their feathers. They do so outside of the egg, relying more on the nurturing nature of their parents.
One of the reasons these birds can get away with such bald, helpless chicks is their nesting behavior. These birds will lay a clutch of eggs in a specially designed nest, safely out of reach from predators. Of course, not all will survive if a predator does find the nest and decides to raid it. But, there is a good chance that some chicks will grow and finish their development before they can become fledglings.
During this period, their feathers will start to grow, providing both the warmth they need and their first flight feathers. Until that happens, they require body heat from their brooding parents. Chicks will leave the nest when they can fly and survive outside the structure, and the parents will still feed them for a while. In the worst cases, siblings may fall from the nest or get pushed out. Unfortunately, without their feathers, they have little chance of survival.
Some birds develop in nests with their parents, but these are not fully altricial. Most altricial birds are songbirds. Birds of prey, such as hawks, eagles, and owls, are born with a coat of downy feathers and their eyes open. They are more developed after hatching than those songbirds but still require care and regular feeding at the nest. These birds are called semi-altricial.
Precocial Birds (Feathers)
There is another image you may have in mind of the fluffy yellow chick. Precocial birds have a different strategy than altricial birds. Often, these birds are ground-nesting, such as waders and waterfowl. These chicks must be ready to handle what comes their way from day one. Precocial birds are born with their eyes open and can run and feed.
The feathers provide all-important warmth. This is essential if chicks stay by their parent’s side and out of harm’s way. Predatory species could swoop in and try and take chicks as a quick snack. This is less likely if the chick can run or swim away and helps to stay by its parent’s side.
It is also common that precocial birds have greater clutches of eggs than altricial birds. Altricial songbirds will attempt to lay two clutches of around six eggs over the year. They spend time carefully raising them in the nest, and hopefully, the large majority will fledge. Precocial birds know their survival rate is lower and will have one big brood or double the size. This increases the chance of some offspring surviving.
Can Precocial Birds Fly After Hatching?
It takes time for altricial birds to develop the skills, strength, and flight feathers needed to fledge and become more independent. For precocial birds, they may be able to get up and move around, but they aren’t going to fly soon after birth. It can take about six weeks for the flight feathers to develop. So, all chicks, precocial or altricial, need protection during this time. Parents will encourage chicks to fly when the time is right.
Precocial Abilities and Behavior Levels
There are five development levels in precocial birds related to their abilities and features straight after hatching.
Superprecocial or Level 1: Birds can independently take care of themselves and have flight feathers from birth. This is not a trait seen in North America. Instead, it occurs with Megapodes like the Australian Malee fowl.
Level 2: Birds have downy feathers and the ability to stay close to their parents as they develop further. They are also able to learn how to feed. Examples of these birds are ducklings and wader chicks that can pick up food by themselves.
Level 3: Chicks have a very similar development level with their downy feathers and ability to get around. Here the birds tend to be shown food more often and are a little more reliant on their parents.
Level 4: Chicks can leave the nest with enough feathery protection but can’t find their food. Examples are grebe chicks that sit on their parent’s back awaiting food.
Semi-precocial: Chicks stay at the nest site after hatching and wait for their parents to return with food. They act like altricial chicks to an extent but can run and have downy feathers.
The sub-category of semi-precocial birds explains a plumage trend in birds like gulls and terns. Many will have a mottled look to their first downy feathers. This helps break up their shape and blend into the ground on a sandbank or stony shore. Those that stay completely still and quiet while their parents are away are practically invisible.
In short, we can categorize birds as either altricial or precocial, which determines whether they are born with or without feathers. Feathers from birds are a necessity for some species and not others. From there, there are sub-categories on the behavior of these birds. It all comes down to the best strategy for survival.