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Where Are The Birds?
Photos & Text by R. Munguia

In recent years we have noticed a decline in the number of species that are seen during fall and spring migration. Many birders complaint of the low number of warbler sightings this year, the absence of winter birds in their feeders or how late they arrive. While the numbers seem to dwindle in well known birding areas, others seem to have new record bird sightings in places no one has ever seen. Yes, birds are complicated, the fact is that of all migratory animals, birds can do this with so much ease and speed than any other. The complexity of migration is far from unveiled even with all the modern technology it's hard to predict what the future may bring. But one thing is for sure on birds, the dynamics of migration as well as their winter/summer ranges are changing. Climate change is here, not just to change climate and the weather patterns, but also those things that are ruled by it.

Climate change is a natural occurrence that will continue its path, regardless of what we do. The problem lies on how quick these changes are occurring. The last ice age it's an example of how climate change works. It's believed that the origins of migration were established even before the last ice age, yet many scientist are debating if some of the North American migratory species that we know today originated in the tropics and later moved up north to take advantage of the surplus food during spring.

Regardless of the origins we now know that migration dynamics are changing as a result of the accelerated climate change. Here's when we human becomes the center of attention. We have contributed to these changes through carbon emission. For the past 150 years the amount of carbon produced by human activities have contributed to the degradation of the atmosphere. Almost everything that we do emits carbon, things such as driving a car or leaving the lights on are a good example. Carbon dioxide as well as other greenhouse gases including methane, and nitrous oxide trap the heat produced by the sun, increasing the overall temperature of our atmosphere. These effects get progressively worst as the heated atmosphere becomes more unstable producing extreme weather systems such as heat waves, windstorms and hurricanes. Forest fires become more prolific and harder to control and intense drought destroy precious wetland systems used by birds. The melting of the permafrost releases large amounts of trapped methane gases, and the uncontrolled fires add to the levels of greenhouse gases, thus accelerating the climate changes.

Unlike amphibians which seem to be at higher risk due to their sensitivity to these changes, birds are currently changing their patterns to cope with the climate change. Many species of birds are nesting farther north than ever before, while others are delaying their fall migration and some are not even migrating anymore. Can this all be connected to climate change? The latest studies show a correlation between bird pattern changes and the increase in temperature in their range. Even in tropical rainforest the effects can be seen. Birds that used to nest in lower elevations such as the keeled-billed toucan are moving to higher elevation during breeding time to take advantage of cooler temperatures and the resulting food supplies. In the United States the number of non-migratory Canada geese are increasing to the point of causing water pollution problems in some northern states.

A 2006 report on Bird Species and Climate Change, warns of bird lost and shrinking ranges that are causing disruptions of the natural communities all around the world. You can access this report through our website at
The long terms effects of climate change are yet to be seen, but the changes that we have witnessed so far are dramatic enough.


Many flocks of Canada geese are not longer migrating, causing major issues in urban areas. If water does not freeze these birds don't find the need to migrate. Besides people feed them at local parks, making food easily accessible.
Birds such as the Robin are migrating shorter distances than in the past. Mild climate during the winter months and temperature inversions provide favorable weather for them to stay near their summer range.

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