Giant Human Sized Salamanders

Every couple of years when we lived in Wisconsin, the woods around us would be invaded by different kinds of newts and salamanders. Although I never did figure out what caused these events, I assume that those waves of critters were related to population booms or some conditions that resulted in 1000s of them running across the driveway and into our garage. I would have loved, however, to see a plague of these guys: http://www.wired.com/wiredscience/2013/10/absurd-creature-6-foot-salamander/?utm_source=tumblr&utm_medium=socialmedia&utm_campaign=tumblrclickthru#slideid-285261