The four most numerous bird species in the world as listed by the National Academy of Sciences (NAS) — house sparrow, barn swallow, European starling and ring-billed gull — are found in Minnesota in substantial numbers.
Of the 9,700 species studied, these four species each have an estimated world population of over 1 billion, according to an article in the NAS journal.
The world estimates are house sparrow 1.6 billion, European starling 1.3 billion, ring-billed gull 1.2 billion, and barn swallow 1.1 billion.
At the other end of the list are 1,180 species, 12% of world totals, each noted as having fewer than 5,000 individuals.

A population of 5,000 or less should be considered shaky ground, according to the article. Those birds face the same problem as our passenger pigeons did, going from billions to never in less than 500 years.
Normal time for a natural extinction would be millions of years, unless, as was the pigeons' fate, humans give nature a huge push. We can define that today as habitat loss exacerbated by climate.
House sparrow numbers in Europe are dropping, according to research published in the journal "Ecology and Evolution." Populations in the European Union almost halved between 1982 and 2017. Change in farming practices was given as one reason for the decline.
"The sparrow population remained the largest among the more than 300 bird species analyzed in the study, but also suffered the most dramatic relative decline," according to study participants.