American robins and purple grackles are common birds on
lawns, meadows and fields through spring, summer and fall in the Mid-Atlantic States.
That is nothing profound, except robins and grackles probably inhabited
woodland clearings and wooded swamps respectively before European farmers
cleared the forests to create farms. These two bird species made great
adaptations to forage for invertebrates in those vast, human-made environments
where vegetation is close to the ground or absent. As the forests were cleared
and farmland created, both these species spread across the countryside and
greatly increased their numbers in what was, to them, an ever-expanding world.
American Robins are members of the thrush family and young robins have spotted chests to prove it. Thrushes are forest birds that receded with the elimination of woodlands. But robins, having been pre-adapted to more open areas, expanded with the expansion of farmland and towns.
Robins, as a species, inhabit the middle Atlantic States the year around because they change their feeding habits. During warmer months they eat invertebrates, but locally wintering robins feast on berries in hedgerows and suburban areas, and shelter in coniferous trees for the night.
Robins that retreat south for the winter, return to this area early in March, bolstering the numbers of their relatives that stayed here through winter. At this time, flocks of scores of robins run and stop, run and stop on lawns, pastures and fields in their search for earthworms and other invertebrates. But if the soil freezes again, or snow covers it, they revert back to eating berries.
Robins nest in shrubs and young trees on suburban lawns as they did in woodland clearings. And because of that, robins are one of the first bird species to nest on the lawns of new suburbs as the planted bushes and trees grow.
By late summer and through autumn, young robins and their elders gather in flocks that roam through fields, pastures and lawns to consume berries and invertebrates. Youngsters are now full-sized with long tails, but are still spot-breasted like their thrush relatives.
Purple Grackles are members of the blackbird family, which includes red-winged and rusty blackbirds. Grackles have striking plumages, with their iridescent green and purple sheens and yellow irises.
Hordes of grackles pour into this area early in March. Their masses settle on fields, lawns and meadows to eat invertebrates, seeds and anything else edible they can handle. But soon their large flocks break into smaller groups that today nest in colonies in planted coniferous trees, which is another adaptation on their part. The adults glean invertebrates from nearby lawns, fields and pastures to feed their young in their nurseries in the conifers.
American robins and purple grackles adapted to human-made habitats, and made them more interesting to us. They were woodland birds that advantaged themselves to open environments, which has increased their populations as they spread with an expanding world. Adapting is a major key to success.
American Robins are members of the thrush family and young robins have spotted chests to prove it. Thrushes are forest birds that receded with the elimination of woodlands. But robins, having been pre-adapted to more open areas, expanded with the expansion of farmland and towns.
Robins, as a species, inhabit the middle Atlantic States the year around because they change their feeding habits. During warmer months they eat invertebrates, but locally wintering robins feast on berries in hedgerows and suburban areas, and shelter in coniferous trees for the night.
Robins that retreat south for the winter, return to this area early in March, bolstering the numbers of their relatives that stayed here through winter. At this time, flocks of scores of robins run and stop, run and stop on lawns, pastures and fields in their search for earthworms and other invertebrates. But if the soil freezes again, or snow covers it, they revert back to eating berries.
Robins nest in shrubs and young trees on suburban lawns as they did in woodland clearings. And because of that, robins are one of the first bird species to nest on the lawns of new suburbs as the planted bushes and trees grow.
By late summer and through autumn, young robins and their elders gather in flocks that roam through fields, pastures and lawns to consume berries and invertebrates. Youngsters are now full-sized with long tails, but are still spot-breasted like their thrush relatives.
Purple Grackles are members of the blackbird family, which includes red-winged and rusty blackbirds. Grackles have striking plumages, with their iridescent green and purple sheens and yellow irises.
Hordes of grackles pour into this area early in March. Their masses settle on fields, lawns and meadows to eat invertebrates, seeds and anything else edible they can handle. But soon their large flocks break into smaller groups that today nest in colonies in planted coniferous trees, which is another adaptation on their part. The adults glean invertebrates from nearby lawns, fields and pastures to feed their young in their nurseries in the conifers.
American robins and purple grackles adapted to human-made habitats, and made them more interesting to us. They were woodland birds that advantaged themselves to open environments, which has increased their populations as they spread with an expanding world. Adapting is a major key to success.
by Audrey ~ flickr
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