The fatalities were a vicious spiral. The males were killing more females, deepening the imbalance.
Which means the next generation would be even smaller and so on and so forth until at one point the thing is reduced to a point where it is no longer sustaining the spiral.
Or at least that's how I imagine it would go.
For better or worse, that point might be a population of zero.
Well, let's just say extinction is not the first definition of "nature righting itself" that comes to mind for this scenario.