Bird Feeding Levels in Water
By Dave Hanks
I wrote an article about the vertical levels, from ground level and upwards to the sky, that various birds frequent the most. This article deals with how different species of birds can use the same water body to feed in because they feed at different levels in the water – thus not stressing the food sources.
Bill shape and makeup, neck length, wing shape, and leg placement; all these varying traits determine where and what a species eats. Mallards and other DABBLING DUCKS bob their “bottoms up” and secure feed just below the water surface. SHOVELERS have a big, scoop-shovel beak that is used on the water surface – as do avocets with their upturned water sweeping bill. Mergansers and other DIVING DUCKS have compact wings and legs set well back on their body. These features offset buoyancy and permit the bird to dive. Their serrated beaks allow the seizing and holding of fish or other aquatic organisms. SWAN with their long necks permit them to reach down to two and a half feet under water when doing their “bottoms up”. Geese are GENERALSTS with legs directly under their body that make movement on land easy, and beaks that allow grubbing of roots, grass, and sedges. This is true also, for Mallards and Wigeon. They, like the geese, will graze in the fields.
Man’s way is to put many individuals of a single species in a specific area. If not exacting in the numbers added, the food source can be badly abused. Nature’s way is to put many species, but less quantity of each in an area. Because each uses the habitat differently, the habitat remains healthy.
Water birds that may seem to have much in common are really quite diverse. The various feeding adaptations are an example of nature’s brilliance!
(Trumpeter Swan: Long. graceful neck, and powerful bill)
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