Bird Feeding with George Petrides
Tips on attracting and feeding backyard birds.
When we look at the sky, it’s like a roof – flat, solid – just sort of there. Unless the light is exceptional, even clouds and constellations looked painted on it.
For the birds though, the sky isn’t flat, it’s multidimensional. Just as different bird species hunt at different levels within the same tree, different birds tend to fly at different levels in the sky. And for them, the clouds aren’t just pretty puffs in the sky. They are a dynamic part of their daily landscape.
Flying high exposes birds to dangers, such as higher winds or hungry hawks. So when not migrating, most birds follow the facetious advice often given to new pilots, they “fly low and slow”, usually under 500 feet. But during migration, birds often climb to remarkable heights, probably to conserve energy. They burn fewer calories in the cooler air and become dehydrated less quickly.
Also, winds that can hinder day-to-day activities become a welcome aid to quick travel. Like pilots, birds seem to know that their optimum cruise altitude increases as their “fuel” is consumed and their weight declines. Long-distance migrants seem to start out at about 5,000 feet then progressively climb to about 20,000 feet. In the Caribbean basin, where considerable radar work has been done, migrating birds are most often observed at about 10,000 feet.
Clouds and Birds:
Altocumulus clouds: Migrating swans and geese are known to sometimes fly more than 25,000 feet above sea level , over four miles high!
Stratocumulus clouds: Broad-winged Hawks routinely soar at around 3,200 feet, aided by thermals created by differing ground temperatures.
Cumulus clouds: Vultures sometime rise to over 10,000 feet, scanning wide areas for food and watching the behavior of distant birds for clues to the location of a feast.
Cirrostratus clouds: Jet planes typically cruise at about 35, 000 feet, in what are commonly known as “ice clouds”.
Nimbostratus clouds: In their daily activities in and around our backyards, many of our favorite songbirds stay in the 30-to 50-foot range above the ground. Robins, bluebirds, jays, woodpeckers, chickadees, and nuthatches are all relatively low flyers.
While these daunting percentages vary by source, they all suggest that about 30% of North American birds are in significant decline, including:
70% of grassland bird species
25% of forest bird species
13% of wetland species
These declines are abnormal; they’re not part of the natural cyclical rise and fall of bird populations. Among the many threats to birds, the most serious is loss of habitat due to poor land-use planning and possibly, climate change. Many remaining habitats are degrading due to fragmentation by roads, over-browsing by deer (for example), drainage of wetlands, poor forest management and invasive species impacts.
Have you heard the term “Important Bird Area”? Although it may sound like a simple term, an Important Bird Area, or IBA, is a powerful conservation concept. In its simplest terms, an IBA is an area identified for its significance to bird conservation. IBAs may be huge and of global importance, like the Chesapeake Bay which is surrounded by the Mid-Atlantic States, or they may be locally important areas like Belt Woods in Prince George’s County in Maryland.
The IBA program identifies sites that provide essential habitat for birds so that conservation efforts can be focused on priority locations. A great strength of the IBA program is that it takes a proactive approach to conserving birds instead of just responding to specific threats - that’s why the IBA program deserves understanding support from us all.