From Tierra Fuego to Panama and all across South America alarm bells are going off in the heads of billions of birds signaling that time is fast approaching to store body fat for the long trek northward to their breeding grounds. I suspect that many Swainson’s Hawks in Chile and Argentina have begun their eight to nine thousand mile spring migration to southern Canada. While it is late summer where they are beginning their voyage, it is far different on the wind swept and snow covered grasslands that will be their final destination. By the time they arrive in May, these prairies will be covered with wildflowers, a dramatic change from present conditions.

From Tierra Fuego to Panama and all across South America alarm bells are going off in the heads of billions of birds signaling that time is fast approaching to store body fat for the long trek northward to their breeding grounds. I suspect that many Swainson’s Hawks in Chile and Argentina have begun their eight to nine thousand mile spring migration to southern Canada. While it is late summer where they are beginning their voyage, it is far different on the wind swept and snow covered grasslands that will be their final destination. By the time they arrive in May, these prairies will be covered with wildflowers, a dramatic change from present conditions.

The end destination conditions have changed very little over the millions of years this migration process has unfolded; only the participants have changed as many generations guided only by their instincts have traveled the long established migration routes. The males are generally to first to take to the air in hope of staking the best ecological niches in their breeding ranges, locations that will help them strengthen their gene pools for long term survival. After completing the migration cycle a number of times, past experiences augment what their instincts are telling them to do to be successful.

Timing is a very important element in the overall scheme of being a winner or loser in the game of life for migrant birds. If an older adult male in order to get the jump on his younger competitors leaves his wintering grounds too early, his arrival might conflict with a later than usual winter storm in his breeding grounds. If the late winter storm eliminates his food supply, he ends up not surviving. On the other hand, if he overstays his time in the tropics, he will possibly lose the rights to the most favorable breeding territories. Some ornithologists argue that migration timing could factor in survival of the fittest as some older males out-smart themselves and lose.

Purple Martins are among the earliest arrivals in South and Central Texas; they have been reported to be on territory by mid-January to mid- February. The exuberant martins could be the older birds seeking an advantage over the younger, possibly stronger, competitors. Many people think that these early arriving martins are merely “scouts” checking out the conditions in the breeding range for later arriving martins. The problem with this theory is these scouts have no way to communicate their scouting reports back to the following masses. My birding friends told me recently that a summer resident, Bell’s Vireo, was heard singing in the Bandera area – hope he can find ways to survive the likely occurrences of cold weather in the near future.

We are two to three weeks away from our first hummingbird arrivals in March. I suspect many of the “early bird” hummer males are in route at this time. March 10 is a good time to put out your sugar water feeders. Some of you may still be feeding over wintering hummingbirds, so you are prepared for all early birds. A few years ago a late winter/early spring cold snap had deadly consequences for many hummingbirds. Normally very cold weather prompts hummingbirds to enter into a semi-hibernation state, called “torpor,” that allows them to survive very cold temperatures. I never heard an explanation why the torpor function did not save these birds.

Remember you have a lot of wintering goldfinches, sparrows and siskins who likely have not had any traveling alarms go off at this time. We need to continue feeding them as their departures are still two months away. And do not forget that we have a large number of permanent bird residents who do not even have instinctive alarm clocks. We can continue to enjoy our permanent and winter residents while we wait for the hard core travelers to begin arriving in a few weeks.

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