It all began nine years ago when Mark Glenshaw was walking in the 1,400 acre Forest Park near his home in St. Louis.
He had been doing this regularly for several years but this time out he said he saw two great horned owls in the park. "The first sighting I had set a really high benchmark. Just was instant addiction. In 20-30 minutes I saw them hoot together, duet, a beautiful vocal and visual display. I saw them fly. Powerful, graceful, silent flyers. And then I saw one of them chase a great blue heron, a bird twice its size and I was completely hooked."
Hooked might be putting it mildly. Glenshaw named the two owls Charles and Sarah and he said he began returning to Forest Park, a lot. "I average between 260 and 300 nights a year." Glenshaw said he has walked through the park in search of Charles and Sarah about 2,500 times since that evening nine years ago which he referred to as his owl-iversary.
I made the walk with him in owl territory a couple of months back. Not surprisingly he now has a pretty good idea where the owls will be in the park and knows where they have been in the past. "Let's turn around and look at this tree. See the big hollow? 20 feet up? That hollow is where Charles and Sarah nested in 2008 and 2012. Three owlets in 2008 and two in 2012," Glenshaw said.
Once he scopes them out, and armed with cameras and binoculars, he usually spends time following the pair around, as best he can from tree to tree. He said, "I've seem them have 21 owlets. They've bred successfully every year. I've seen them mate. I've seen them nest. I've seen them raise their young and then start all over again. Year in, year out. Every year is different. Every evening is different."
It wasn't long after finding Charles and Sarah that he began doing what he calls owl prowls. More than 60 of them in 2014 alone where maybe a half-dozen folks go with him on his early evening search for the great horned owls. "A two-hour guided tour of the owls territory where we look for and observe the owls while I discuss, while I interpret the natural history of the great horned owls," Glenshaw said.
He does some of the owl prowls in conjunction with the Academy of Science in St. Louis. Mary Burke is the CEO of the Academy. "Based on the information he had, the detailed information from watching these owls and their habitat and how they lived, we knew there was something really spectacular about him," she said.
Glenshaw has also been a mentor to many like Brenda Hente of St. Louis County. Two great horned owls hang out in a park near her home. After meeting Glenshaw, and learning more about the owls over time, she said it has accelerated her interest in them and changed her life. "And then there they were every single day hooting or in the evening I would hear them hooting. It just got a hold of me and turned me on to nature in general and everything that nature has to offer."
You might think that in the winter Glenshaw would cut down on his ventures into the park. He said that's not been the case. "A gray, tough, cold winter day was just not my favorite and now it often is. Just because I know I am going to see the owls and something really cool is going to happen that night. It's just not a day to get through, it's a day to look forward to and enjoy."