By Audrey Posten, North Iowa Times
For roughly 10 years, a group of local caving enthusiasts has made an annual late-February sojourn into Spook Cave, surveying and counting the bat population that’s taken up winter residence in the McGregor-area tourist attraction.
In the early years, around 100 bats could be seen, said volunteer Gary Siegwarth. That number grew over time, surpassing 300 as recently as 2016. Last year, however, the population plummeted, with only eight bats located. This year, the number shrunk again, as just four bats were observed.