Two men posing with a 'Punt Gun', a kind of shotgun for hunting waterfowl in large quantities, 1923

And somehow massive fishing nets still allowed.

Here's a song about what these guns accomplished.

For the best, but I can't say I'm not morbidly curious as to what the result of one of these monsters would look like. A flurry of feathers and falling bird corpses, I would expect.

decimate bird populations

decimation then:

In the military of ancient Rome, decimation (from Latin decimatio 'removal of a tenth'[1]) was a form of military discipline in which every tenth man in a group was executed by members of his cohort.

and now:

The word decimation in English is often used to refer to an extreme reduction in the number of a population or force or an overall sense of destruction and ruin.

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