That’s interesting. A fine distinction though - Zebra Mussels, Noctua pronuba and the Emerald Bark Beetle I would consider to be invasive to NA. Others that migrate here on their own I would not consider as invasive. This thread - https://forum.inaturalist.org/t/great-tailed-grackle-in-north-america-introduced-or-not/30425/2 - would illustrate that difference.
The distinction may be defined by how much of a pest (which is another category!) the organism is. If, like the Emerald Bark Beetle - the species causes the reduction of native species (American Elm) I would call it invasive. Agricultural pest species, like Flea Beetles introduced to to NA, I would class as something else. I don’t know what. I don’t think that they bother the local Cruferiadae much but can devastate a Canola crop.
In New Zealand they have a category of ‘Self Introduced’ mostly for birds that have migrated in some way across the sea from Australia. It’s all very complicated!
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