Sep 30, 2026 · 2 min · 5 segments
In Lafayette Park in St. Louis, Missouri, a dozen or so Eurasian Tree Sparrows from Germany were released. But unlike other introduced species such as the similar-looking House Sparrow, they did not…
[house sparrow chirping] The House Sparrow, introduced to North America from Europe in the mid-1800s, has spread across the continent and can be seen grabbing french fries off the sidewalk from coast to coast.
They often compete with native species for nesting sites.
In the 1870s, another European sparrow came to the US, but had a completely different fate.
[Eurasian Tree Sparrow chirping] In Lafayette Park in St. Louis, Missouri, a dozen or so Eurasian Tree Sparrows from Germany were released.
Their descendants fanned out across the city and its suburbs.
Eventually, some moved up the Mississippi River to Illinois and southeastern Iowa.
But that's about as far as they traveled.
[Eurasian Tree Sparrow chirping] Unlike House Sparrows, Eurasian Tree Sparrows haven't become invasive in North America.
It's not fully clear why, but it's possible that they just behave differently, and the aggressive House Sparrow may have helped prevent the Tree Sparrows from spreading further by competing for the same nesting sites.
Eurasian Tree Sparrows still remain in a small area of the Midwest, where they're not much of a nuisance to native birds and are a local curiosity for birders.
[house sparrow chirping] The House Sparrow, introduced to North America from Europe in the mid-1800s, has spread across the continent and can be seen grabbing french fries off the sidewalk from coast to coast.
They often compete with native species for nesting sites.
In the 1870s, another European sparrow came to the US, but had a completely different fate.
[Eurasian Tree Sparrow chirping] In Lafayette Park in St. Louis, Missouri, a dozen or so Eurasian Tree Sparrows from Germany were released.
Their descendants fanned out across the city and its suburbs.
Eventually, some moved up the Mississippi River to Illinois and southeastern Iowa.
But that's about as far as they traveled.
[Eurasian Tree Sparrow chirping] Unlike House Sparrows, Eurasian Tree Sparrows haven't become invasive in North America.
It's not fully clear why, but it's possible that they just behave differently, and the aggressive House Sparrow may have helped prevent the Tree Sparrows from spreading further by competing for the same nesting sites.
Eurasian Tree Sparrows still remain in a small area of the Midwest, where they're not much of a nuisance to native birds and are a local curiosity for birders.
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