Why do woodpeckers, ravens, crows don’t migrate
You must have heard about birds migrating during unfavourable climes. Generally, birds from temperate zones migrate and the main reason why they do so because their food supplies are seasonal. These are the birds that primarily eats insects (like swallows and flycatchers), fruit (like orioles) or flower nectar (like hummingbirds) and they have to migrate when their food supplies dwindle.
But do you know that not all birds do that. Many birds stay put in their own areas, for varying reasons. These are birds living in tropic region. They stay put in their own area because they do not face food scarcity. These include woodpeckers, hawks, owls, ravens, crows and jays.
Benefits of staying put
Migration can be life-threatening. Birds that do not migrate save themselves from predators, hunters and extremities of weather.
Migration needs lots of energy. So birds that don’t migrate don’t need to expend massive amounts of energy to travel. They can utilize that energy to strengthen their survival. They can indulge in foraging, defending their territory and also increase their population.
Birds that don’t migrate can enjoy superior habitats throughout the year, which the migratory birds lose when they travel.
Non-migratory birds can give more time to their young ones as a result of which their offspring are strong and healthier than those of migratory birds.
So what are the peculiar characteristics of non-migratory birds:
These birds cache food in late summer and autumn, hide their supplies of seeds and nuts in protected areas, like under a tree bark, wedged into tree crevices or bury their foods instead. The food is retrieved when the need arises.
Birds that stay throughout the year in extreme northern habitats do not molt in late summer. As against that during peak winters, they gain an extra protective layer of insulating down feathers to help preserve body heat that protects them from extreme cold. These birds may molt again during spring season and develop a brighter breeding plumage or they may shed the excess feathers.
Non-migratory birds generally have aggressive and dominant personalities. They are curious and intelligent which helps them defend territories from hungry intruders, seek out unusual resources such as roosting in unique spaces and try new foods or visit feeders more often.
Many birds that stay in the same range year-round forage together during the winter which is beneficial to them. Many smaller birds, such as chickadees, wrens and downy woodpeckers, flock together in winter.
Many small birds that don’t migrate, such as tits and chickadees, will crowd into any available cavity for overnight roosting, and these birds that roost together have a better chance of surviving a sudden overnight cold snap because of their shared body heat.