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 Most of our birds migrate to some extent. The exploits of some are legendary. Arctic terns probably hold the world record by winging 18,000 km non-stop between the Arctic and the Antarctic twice each year. Some that we consider year-round residents, such as Cardinals and Bluejays, may make short migrations; though you see them in your yard year round, they might be different individuals at different times of the year.
There are three really exciting phases to bird migrations in Louisiana. One is the arrival of oodles of water birds that spend their winter with us. These include ducks, geese, loons, and the spectacular white pelicans. The other two are the fall (peak in September) and spring (peak in April) arrival and passage of warblers, sparrows, tanangers, flycatchers, and more as they travel between the tropics and our temperate zone. Louisiana’s coastline is a critical point. In the fall it is the staging area for waves of tiny birds striking out across the Gulf of Mexico en route to tropical wonderlands. Each spring, the same coastline is the landfall for rest and rebuilding burned energy stores after the arduous flight from the south.
We tend to think of these movements as “our” birds going south for the winter, only to return each year to their true home. After all, they breed here so this must be their base of operation. But is it? While in the tropics, they spend their days fending for themselves, feeding and avoiding predation. Some of them have very different lifestyles, moving in mixed flocks and acquiring their resources in a group effort. Others may choose habitats unlike those used during the summer. But one constant exists. At some point, they begin to move northward.
 Why do they migrate such long distances? What would lure such a small creature so far away? They key may well lie in the distribution and availability of food. In very general terms, these aspects of food dispersal remain constant in the tropics. They do vary with rainfall in some regions, but temperature and day length are relatively constant. In our temperate areas, food sources for small birds are slim during cold winters. But when spring arrives, things change rapidly. All life stages of insects and other invertebrates are suddenly everywhere. Flowers bloom and seeds are widely available. The temperate zone provides the southern birds with an open pantry of delectables at the critical moments of their arrival and, biologically their most important period, reproduction. Can you imagine a better life strategy than to live in a constant environment and migrate to an area that is flush with food at the instant that the energy-consumptive reproductive period begins? It makes sense that increased reproductive success, the most important function of an individual, would be an adequate carrot to lure that individual into a death defying flight over such a long distance.
If you like birds, this is the best month to visit Venice, Grand Isle, and Peveto Beach in Cameron Parish to see the many species and scads of individuals of tropical migrants arriving for their summer visit
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