The beauty of the nest

When walking along the banks of Malibu Creek where it meets the estuary, I was astounded by the diversity of bird life. Among the resident mallards, snowy egrets and coots was a greater scaup, Aythya marila, and a northern shoveler, Anas clypeata. As the day progressed, more and more winter migrants made their appearance, adding to the already prolific wildlife.

By the time I had made it to the ocean my mind was reeling with thoughts of migration and home. Certainly these protected brackish waters were home to these transient ducks, but wasn't their summer residence also home? What about stopping places en route? Were those their homes as well?

From watching the behavior of animals, and certainly birds, my definition of home has broadened considerably. Even in hominid history we see that home was not as definite as we deem it today.

Presently, home conjures up thoughts of a fixed, sedentary place that doesn't change location. But for humans dependent on foraging and hunting for subsistence, home was defined more by ancestral burial grounds and places of worship than by the structure in which they slept. Home among huntergatherers was temporary, dependent on migrations to seasonal food harvests. Boundaries often shifted, suiting peoples' needs.

IRIS SMOOT/Acorn Newspapers FOR THE BIRDS- A young lesser goldfinch snacks on seeds during the last few minutes of light near Oak Park High School on Sunday afternoon. With the coming of spring, wildlife has been active and plants blooming.

Transient notion of home

As with early humans and subsistence cultures of today, many other animals share a transient notion of home. Rather than a fixed spot, home is associated with a region. Birds especially embody this expansive notion, some traveling many miles while others diligently search their small habitat for a secure place to lay their eggs.

Regardless of how a bird finds its temporary home, each spring I am awed when I come upon a nest. It seems as if a miracle is to unfold. From a place where there was nothing, an architectural marvel is constructed for the sole purpose of holding precious eggs that crack and bring forth new life. That life is cradled within the temporary home only long enough for flying lessons, then home is abandoned with the birds' yearning to stretch their wings.

Maybe that is one of the greatest mysteries to humans, this abandonment of the nest. After so much energy was expended and family history built, how many people would readily abandon their homes?

To me that is the beauty of the nest- its transient nature. Nests are built for one reason, to protect and insulate tiny packages of egg life. Over millennia they've evolved to become more and more advanced, meeting the needs of bird adaptation and predation pressures.

The first nest, 135 million to 70 million years ago, was thought to be a naturally or birdmade scratch in the ground preventing eggs from rolling away. The simple scrape nest, still used today, was improved upon by gathering materials around the scrape on the ground. Surpassing these nests were raised platforms built above the ground. From there, nest construction broadened wildly.

Diverse architectural styles

The amazing nest diversity evolving from the scrape gives us a greater perspective into the complexity and character of birds' lives. From Ehrlich et al. (1988) and Elbroch & Marks (2001), nest types are separated into nine categories, the most primitive being the scrape, which is used by shore and seabirds, some raptors, and nightjars. Another configuration is platform nests, preferred by wetland birds, raptors and owls. Platform nests may be on the ground, elevated or floating.

The crevice is another nest type, where birds choose to build in the openings of rocky ledges, cliffs or man-made structures. A fourth, and the most widely recognized nest, is the cup, which looks like half a sphere. Each cup nest is unique to the bird species as well as its habitat. Another type of nest is the saucer, which looks like a shallow cup nest.

Spherical nests are ballshaped with a small entrance; dippers and magpies are exemplary sphere builders. Pendent nests are finely woven teardrops that hang from the most outer branches of a tree or shrub; orioles are one of the builders of these "hammocks."

The last two categories, cavity and burrow nests, are often grouped together. These nests are excavated or modified by the dweller within. Cavity nests are often found in dead trees called snags, while burrow nests are constructed in the ground. Woodpeckers make cavity nests, and kingfishers craft burrows.

The more I uncover the intricacy of nest architecture, the more I am stunned by bird homes. But more awe-inspiring is the birds' nature to leave their homes, allowing the nests to return to the earth or to others in need. Rather than permanently scarring their surroundings, nests disintegrate, letting the space around breathe and replenish. What would it mean to release our homes and permit the earth underneath to breathe?

Meghan Walla-Murphy can be reached at the following email address: mwallamurphy@ yahoo.com.