Mark Glenshaw has been studying owls in Forest Park for the past 14 years. It’s a hobby he takes very seriously. Most days, you can find him walking through the park near dusk in layers of clothing (depending on the season), sporting a massive camera to capture the elusive creatures.
What started as just an interest has developed into an obsession for Glenshaw. He’s given lectures across the country about the nocturnal creatures. In addition to public talks, he leads owl prowls through Forest Park that help to educate and allow people to see owls, an animal so elusive that many people live their whole lives without ever seeing one, for themselves.
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What sparked your interest in owls? “When I first saw the owls in Forest Park, I didn’t write the date down. It was late August or September of 2005, and I thought it wasn’t in the cards that I’d see them again. But, the first sighting took my already high love and interest for the park, and the park’s wildlife, and just poured gasoline on that fire. What I mark as my ‘owl-versary’ is a date I did mark down:: December 29, 2005. That’s when I began to see them more consistently.”
What does a typical owl prowl look like? “They are typically two hours long, and we meet about 60 to 70 minutes before sunset. This is when the owls start to wake up and become active. I do limit it to 10 people. More than 10 people is, most importantly, too much for the owls but is also usually too much for me. A lot of it is standing around and waiting, so it’s important to dress properly. But, if you’re well-prepared, you’re going to have a really good time.”
Can people of any age attend the prowls? “The age limit is no children four years or younger. Kids and prowls often work very well. You know your child, and your five-year-old might be ready to go, but your eight-year-old might not be. It all depends; I’ve had 50-year-olds who are more difficult than five-year-olds. I’ve had families who have attended the prowls many times, but I lead the owl prowl; I don’t babysit.”
What do kids learn on the prowls? “I teach them as I teach adults, but I adjust accordingly at the same time. For example, I loved Sesame Street growing up because it treated me like I was an adult, to be smart, engaged, and ready to learn. I pride myself on being able to adjust my prowls to the people on the prowl and that I lead owl prowls for a wide variety of people.”
What are people most surprised to learn about owls? “I think that people are most often most impressed with how adaptable Great Horned Owls are, and in so many respects. Their huge geographic range allied with their ability to live in so many different habitats including city parks and residential neighborhoods while hunting and eating everything from insects and small mammals to herons, raccoons and hawks surprises many people.”

What is the best mindset for people going on a prowl? “The way I look at it is, we are guests. No matter how we get to the park or what we do in the park, we all finish the same way by packing up and going home. The owls sleep here, hunt here and live here; it is their home.”
What is your favorite reaction you get from people? “One of my favorite reactions is when people really gain a better understanding of what’s out there. ‘There’ meaning their neighborhood, Forest Park or wherever. I love it when people who go on prowls tell me ‘Hey, Mark, I now think of Forest Park in a totally different way.’ I just want people to get thinking about what’s out there and what they can see.”
If you would like to go on an owl prowl, contact Glenshaw at [email protected] with three or four dates that work for you. Due to the volume of requests he receives, Glenshaw might not be able to satisfy your request.