What is a swamp?
Swamps and marshes are wetlands that capture the overflow of rivers and oceans. This important ecosystem is vital for preventing further flooding inland.
Also, it provides habitat for a variety of plants and animal critters. Alligators, frogs, insects, fish, crabs, turtles, mammals, and birds live in swamps (with trees) and marshes (with grasses).
Songs From the Swamp
Out of these soggy bogs of North America comes the consistent and predictable trills of the Swamp (Marsh) Sparrow.
Now, these little rusty-winged, red-capped songbirds have a limited ‘repertoire’ (they only know a few songs). But they have learned to sing these songs perfectly and pass them on for generations.
Fun Fact: According to, Nature Communications, the swamp sparrow has passed its songs down for more than 1500 years.
When the babies leave the nest, they mimic the sounds of the other Swamp Sparrows. They learn to sing it precisely ‘by ear’, until they don’t make mistakes.
Ornithologists Falling in Water
Bird scientists (Ornithologists) studying the continuity of the Swamp Sparrow’s song have also discovered that aging birds lose the quality of their voices.
With delicate sound instruments, they waded into the swamps with recorded songs of swamp sparrows of different ages. After several slips into the muddy waters, they rescued the sound equipment, and continued their experiments.
They released five-minute bursts of the song pattern of two-year old birds and 8-10 year old birds (the outer age of wild sparrows).
Can Old Birds Sing?
Well, yes – but apparently, not as good as young birds. Researchers call this, ‘voice degradation’, which means a lessening of quality in something.
The song recordings of the young birds caused a flurry of activity among the swamp-dwelling sparrows. They were agitated and twittered frantically. The song recordings of the older birds did not result in such a reaction.
Why?
This Land is My Land!
Animals, birds included, are very territorial. They are particular about who enters their space. Young birds, in their stage of nest-building and mating, were disturbed by the songs of other young birds.
They could recognize, by the quality of the song, that the intruder was a threat or competition. They differentiated the ‘degraded’ tone of the older bird’s songs and were not threatened.
Females, especially, were sensitive to the pure tone of a young male’s song. This difference is not perceived by the human ear.
Amazing, but true.
Watch and Listen to the Song of the Swamp Sparrow
Categories: Beaks & Bills, Nature