The Gulf coast from Texas to Florida is the first stop in North America for many songbird migrants. It is also their most important stop, because they have just finished the longest and most dangerous leg of their journey. Warblers, thrush, flycatchers, and tanagers, just to name a few, fly across the Gulf of Mexico after departing from the northern shores of the Yucatan Peninsula at sunset the night before. They fly fifteen to twenty hours non-stop and are pushed to their physical limits. Weather radars along the US coast start picking up clouds of migrants around noon, and they come in wave after wave for the rest of the day. Radar images have shown up to 50 million birds arriving along the coast every few hours during the peak period of migration. As soon as they make landfall they start looking for food. Most have just burned off close to half of their body weight, fat that was laid down in Mexico just a week before.

To successfully cross the Gulf, and to complete even the shorter legs of the journey that follows is possible only if birds can find habitat along the way that provides a rich food supply for the tens of thousands of birds that will stop there during migration. Birds cannot afford to eat only as much food as they need to stay alive but must overeat to lay down fat stores that will fuel their long flights. In poor stopover habitat it may take them days to build up enough fuel to continue their journey. Birds do not fly every single night but rather time their movements according to their own energy reserves and favorable weather conditions.

Stopover habitats are crucial for migration. Humans have taken over so much land that good stopovers have become fewer and farther apart. Along the Gulf coast the offshore barrier islands are life rings for spring migrants that have run out of steam crossing the Gulf because they hit a headwind and have burned up their fat faster than expected. They can land on the islands, far short of the mainland. It is unknown as to how many birds do not even make it to the islands and die when they hit the water. They spend several days on the island looking for food in the pine forest and scrub, then continue on their way.

The problem in conserving stopover habitat is that there is so much diversity of needs among the many bird species. Human development along our shores has taken away pine forests and scrubby growth which provided so much of the necessary diversity.

The wonder of migration is that for thousands of years instructions have been passed down in the birds DNA. Birds automatically take crosswinds into account as they fly, correcting for being blown off course. They "know" to stay on the ground when headwinds are strong, feeding while they wait for the winds to shift. Their basic navigation system is built in, programmed in their brains from birth. Even a young bird, just a few months old can easily fly by itself thousands of miles to a winter home in South America. In spring, it can just as easily fly a different route thousands of miles to find a breeding territory even though it has never made the trip before! And this migration takes place at night without many visual cues! Birds use the sunrise and sunset, the magnetic fields of the earth and the night stars to navigate. Some songbirds migrate by day, such as birds that catch insects in flight, such as swallows. Most songbirds fly exclusively at night because the natural air conditioning cools their bodies as their hearts beat some five hundred times per minute, generating heat. The air is also less turbulent during the night, so the birds expend less of their precious energy.

Sadly though, the simple nature of the cues that birds use for navigation may be their downfall in today's modern world. The stars that help to guide nighttime migration can be a fatal attraction that brings songbirds face to face with manmade structures like buildings and television towers.

Birds are programmed to use the subtle lights of the stars and moon to guide the long night flights. It is only in the past hundred years or so that the darkness under their wings has been replaced by enormous cities that light up the sky from miles away. Celestial signposts become masked in cities where bright lights shine from skyscrapers and rooftops, literally blinding birds and confusing their navigation system. Especially on foggy nights or nights with low cloud cover, when they cannot see the real stars, birds stream toward the city lights and circle among the buildings and streets, disoriented and exhausted. Before long, the birds fall like rain. Many hit windows in a frantic but confused effort to escape the strange and hostile environment that is totally lacking in food. The birds that stream north each spring encounter dozens of major cities in a deadly obstacle course.

Some cities, such as Toronto and Chicago have instituted an awareness program where major skyscrapers turn off their floodlights during the main migration season. Programs like this came into being after people were made aware of the shocking body count of dead birds. A single building in Chicago used to cause fifteen hundred migratory bird deaths each year!

The Audubon Society in New York City has a program called "Project Safe Flight" which has been monitoring bird casualties since 1997. Before the 9/11 disaster, the World Trade Center was a major obstacle for migratory birds and the Audubon Society had successfully campaigned for netting over some windows so birds would harmlessly bounce off. The Tribute in Light memorial of the two lost towers was a giant magnet to migrating birds with its eighty-eight massive spotlights that lit up the night sky one night in 2004. The shafts of light revealed thousands of migratory birds had been drawn to the lights and circled around confused and blinded.

Toronto is the first city in the world to implement a migratory bird protection policy for bird friendly building design and minimized nighttime lighting. Floodlights are especially deadly for migrants when they are pointed skyward to illuminate a building's features. Also, highly reflective windows cause hundreds of fatalities every migration season.

Skyscrapers are not the only buildings that kill birds; even two story office buildings or homes can be lethal. Tired and desperate migrants fly toward what they think is an opening, then hit the glass hard resulting in injury or death. We can all help migratory birds if we turn off outside lights during migration season.

Birds fly into almost any tall structure that knifes up into the sky. Most songbirds fly at altitudes of two thousand feet or less, a strategy that has worked perfectly well for thousands of years until man began building structures of great stature.

Radio and television towers are notorious killers, as are tall emission stacks of factories and coal burning plants. These structures are lit at night so planes don't crash into them, but this has the opposite effect on birds which are drawn to the lights especially during bad weather. In fall of 1977, one television tower in Elmira, NY killed at least four thousand migrants, including more than a thousand bay-breasted and magnolia warblers and hundreds of ovenbirds and Swainson's thrush. A tower in Youngstown, Ohio, killed three hundred ovenbirds during one fall migration. Two towers in Nashville killed more than six hundred ovenbirds and eight hundred Tennessee warblers in ONE night!

On clear nights birds tend to fly at a higher altitude, above many of the towers and structures and may be able to veer around them at the last minute. But, on foggy or stormy nights birds fly closer to the ground and are attracted to the tower lights and they may never see what hit them.

Communication towers, some more that two thousand feet high blanket the migration paths of birds in the US. There are over fifty thousand lit towers and another five thousand new ones are added every year. The US Telecommunications Act of 1996 requiring television stations to provide high definition broadcasts will result in the construction of hundreds of "mega towers" each over one thousand feet tall topped with multiple lights and dozens of guy wires. This all makes for quite an obstacle course for migratory songbirds!

The US Fish and Wildlife Service estimates that between four and five million birds are probably killed at communication towers each year, but the actual numbers could be ten times greater. They found that towers that use white strobe lights that flash every two to three seconds seem to be less lethal than towers that use blinking red lights or constant red lights. Red lights caused birds to circle or hover which ultimately could lead to a greater risk of collision with the tower or guy lines.

Wind turbines are exploding in number, too and at over three hundred feet tall with giant whipping blades are responsible for killing many birds. Thousands more of these are to be constructed. The design changes for these new turbines hold some promise - they are tubular in design with no perches or nesting sites that might attract raptors, which are often killed by these structures. They are also spacing the turbines farther apart with blades that rotate more slowly.

The statistics from wind farms though, continue to be grim: a recent study reported 888,000 bat and 573,000 bird fatalities (including 83,000 raptor fatalities)per year. Wind farms in Minnesota, Wyoming, Colorado, Oregon and Wisconsin find that almost 80 percent of their fatalities are migrating songbirds who hit the turbines at night. Conservation groups support wind farms because of the obvious need for clean renewable energy but at the same time they find themselves in bitter fights with the wind energy industry because they believe not enough care is being taken to assess sites for wind farms, or to manage wind farms to minimize bird deaths. Large wildlife kills can happen at wind farms if they are placed in critical migratory paths.

Unfortunately, migratory paths and prime locations for wind farms are similar. Scientific evaluation of sites for wind farms is essential to ensure that the thousands of new turbines that will be erected over the coming decade do not kill millions of birds and bats. If wind farms are monitored closely during operation, then turbines can be turned off at critical locations, or times of year, to minimize their impacts on wildlife. Just as some major cities in the east turn their lights off at night during migration, the turbines could be turned off for a few hours every night to allow safer passage for birds.

This ends my sixth installment. Watch for our next Newsletter where I will continue sharing what I have learned from Dr. Stutchbury's eye-opening book "Silence of the Songbirds". Her writings have touched me deeply and I just had to share it with all of you.

Linda