Birds' Nests in Winter

     Birds' nests are more visible in deciduous trees and shrubs during winter in southeastern Pennsylvania, as everywhere, than in summer because those woody plants are bare of foliage, revealing the treasures they harbored in summer.  I often see the beautifully built nurseries of Baltimore orioles and American goldfinches in winter when I am out exploring nature.
     Though they are from different bird families, Baltimore orioles and American goldfinches have some characteristics in common.  Males of both these common species in summer have brightly colored feathers to impress other males of their kinds to stay out of their nesting territories and to attract females of their types to raise young in their nesting territories.  Male orioles have orange and black feathers and male goldfinches have yellow and black plumage.  Female orioles, however, have light-brown and pale-orange feathering and female goldfinches have olive-yellow plumages.  The females are not as gaudy as their mates so that camouflage can protect them against predation from hawks, cats and other predators.
     Females of both these species build attractive cradles to hatch their young, although male orioles help their mates with that construction.  And the intriguing nurseries of both species are amazingly well constructed by birds that had no previous training or experience in nest building.
     Foods of orioles and goldfinches are different.  Orioles eat invertebrates they find in tree foliage, and mulberries, cherries and grapes.  Goldfinches, however, consume seeds from grasses, and weeds such as dandelions, dock, thistles, asters and many others.  Goldfinches begin raising offspring in mid-summer so they can regularly feed a porridge of pre-digested, regurgitated seeds to their young.
     Baltimore orioles nest in meadows, along tree-lined rural roads and streams in farmland, on lawns in farmyards and other, open habitats dotted with tall trees.  Each female oriole suspends her cradle on a few outer twigs at the end of a limb on the outside of a tree, and over a waterway, road, pasture or lawn, about 12 to 50 feet high in a sycamore, American elm or other kind of tree.
     Each nursery itself is an eight-inch-deep pouch of tightly-woven plant fibers, grape bark and grasses with long stems, all of which are also anchored to tree twigs.  The inside of each nest is lined with dandelion fluff and soft grass stems.  There those cradles hang and swing in the wind like pendants.  Each female oriole lays four or five eggs in her swinging nursery, which might be subject to being preyed on by crows, blue jays, tree squirrels and other predators.  
     American goldfinches inhabit overgrown, weedy fields, which are dotted with shrubbery and small trees.  Each female goldfinch builds her open cup of three inches across on the outside and two and a half inches deep in a crotch of three adjoining twigs in a shrub or young tree on a lawn near weedy fields, or in an overgrown field itself.  Each nest is composed of weaving rootlets, fine grasses and plant fibers together, and spider silk to lash that nursery tightly together and attach it to the supporting twigs.  Each cup is lined with fine grasses, cattail fluff and thistle down.  And each female lays about five eggs in her exquisite, little cup.  
     When outside in winter, look for Baltimore oriole and American goldfinch nests in trees and shrubbery in the more open habitats of the United States.  They add more beauty and intrigue to          outdoor trips in winter.