Irruption:
- The action of irrupting or breaking into; a violent entry or invasion; an inbreaking; an intrusion.
The Trojan irruption into the Greek camp is related in Book XV of the Iliad. - (ecology) An abrupt increase of an animal population.
Extreme rainfall events predict irruptions of rat plagues in central Australia. - (by extension) An abrupt increase in the size of a movement or organization.
How can we explain this irruption of young people self-identifying as socialists? [Wiktionary]
Noted in “Massive waves of squirrels once roamed America. No one knows why.”, John Kelly, WaPo:
“They were real events,” said University of Wyoming biologist John L. Koprowski, co-author of “North American Tree Squirrels.” John James Audubon was among the reputable witnesses of what are more properly called emigrations, not migrations. Caribou migrate, moving back and forth between habitats. These squirrels were on a one-way journey. Another term biologists use is “irruption.”
