Completely made up maths here, just to make a point ..
Say;
1. The residual number of hardcore 'twonks' in a given population abandons 1,000 animals a year.
2. For every 500 of those animals rescued 'twonkism' increases and results in 501 abandoned animals per year more ..
Needs no further explanation (I hope?) and that is DEFINITELY what is going on.
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