Mark Glenshaw snapped this photograph of “Charles” the great horned owl perched in an evergreen in Forest Park. (click for larger version)
March 28, 2012CLICK HERE for more photos.
On any given day, owl enthusiast Mark H.X. Glenshaw can be found in Forest Park studying a pair of resident great horned owls. Charles and Sarah – so named by Glenshaw – have captivated him since he first set eyes on them in the fall of 2005.
"Charles and Sarah are the Brad Pitt and Angelina Jolie of birds," said Glenshaw. "They are stunning."
Glenshaw, access services coordinator at the Pius XII Memorial Library at Saint Louis University, has lived near Forest Park for several years. He didn't start exploring the park with any regularity, however, until the early 2000s, when he began to seriously take up wildlife watching.
"I had started to find cool things: coyotes, muskrats, red tail hawks," he said. "I had heard from reputable people that there were owls in the park. I knew enough to know that I did not have a good chance of seeing them. They're active when we're not, they're incredibly well-camouflaged, and they can fly fast and silently."
He began seeing the pair consistently in December 2005 – what Glenshaw calls his "owliversary." It was a life-changing experience.
"When I started with this work I had one book on owls," he said. "Now I definitely have over 30."
Seeing the owls, he said, is a great cure for a bad day.
"I often say, 'If you're having a tough day, take two owls and call me in the morning.'"
Mark Glenshaw, a self-taught naturalist, on a recent owl-sighting excursion in Forest Park. Glenshaw has been exploring the park’s wildlife for the past 12 years.
photo by Bill Burckhalter (click for larger version)
Glenshaw grew up in the Washington, D.C., area. His father was from South Africa, where the family gathered recently for a family wedding. He settled in St. Louis after graduating from Washington University.
Since his initial sighting of the pair of owls in 2005, Glenshaw has become quite adept at locating them in the park.
"I've gone from a success rate of seeing them one in 10 attempts, to three in 10, to 10 in 10," he said. "Last year I had a 100 percent success rate."
Charles and Sarah have their home territory in the park, where they live in a hollow tree; and their home range, where they go to hunt.
Glenshaw does not like to broadcast their exact location for the safety of the owls, and the safety of visitors – the talons on the birds can be lethal. He does, however, welcome inquiries from passersby in Forest Park if they see him observing the owls. He also leads owl prowls on a regular basis.
Over the years he has mentored several people who have taken to watching the owls almost as religiously as he.
Brenda Hente, who teaches middle schoolers at Immanuel Lutheran in Olivette, is one of Glenshaw's protégés. Hente, who had a pair of great horned owls living in her backyard, contacted Glenshaw last winter after reading a story about his work.
"I couldn't believe there was someone who was watching the great horned owls in Forest Park like I had been watching mine in my backyard," she said.
Glenshaw came to see Hente's owls, which she named Will and Kate; and Hente went to Forest Park to see Charles and Sarah.
"Mark is just always welcoming, always inviting," said Hente. "He's my mentor, and he calls me his mentee. He's very proud of his owl mentees – me, and our other friends, Barb and Chris – really follow these owls with him."
When Glenshaw went on vacation for a week, Hente stepped in to keep track of Charles and Sarah's activity.
Glenshaw has given talks at Immanuel Lutheran, both at the school and for church groups. He would eventually like to share his knowledge on a broader scale, possibly by writing a book for adults or children.
"It's just amazing Mark is so willing to share with anyone and tell anyone about these owls," said Hente. "He has spent so many hours following them, observing them and documenting them, which is very labor intensive."
A New Generation
Sarah” the great horned owl with owlets “Velvet” (left) and “Christopher.”
photo by Mark Glenshaw
(click for larger version)
In January, two owlets joined Charles and Sarah's family, the 14th and 15th since Glenshaw began monitoring their activity. After much deliberation, he named the largest one Christopher, after the late author Christopher Hitchens. The smaller owl was christened Velvet, in remembrance of a beloved family dog, which died in October.
Owlets grow extremely fast, said Glenshaw. When they were just four to five weeks of age, the owlets had already attained 50 to 60 percent of their adult height and weight.
"At first the owlets are fed by their parents, then the food is dropped off, then they start to grab it," he said. "It takes a long time for the owlets to learn how to catch their own prey. In 2008 Charles and Sarah had three owlets. I saw one go for a squirrel. He missed it by a mile, but the next time he got closer, and made a second attempt.
"It's not smooth sailing, even for top level predators like them," he added. "As youngsters they are vulnerable to red tail hawks, coyotes, raccoons. Once they mature no one's going to mess with them unless they're hurt or sick."
Glenshaw said great horned owls have the widest range of prey of any owl in North America, but that being a predator is still very hard work.
"The prey doesn't come hand delivered, they have to catch it – they mostly go for eastern grey squirrels but like all predators they miss more than they succeed," he said. "They are one of the few animals that eat skunks; they eat insects, they fish, they catch bats in flight."
It's easier to list what they don't eat, he said, like fox, coyote, deer or snapping turtles.
When the owls are ready to leave the nest Charles and Sarah will help them along, said Glenshaw.
"Parents, especially of teenagers, can relate to this," he said. "The parents will stop feeding the owls in late summer or early fall. If they don't get the message they will chase them off."
This is after months and months of very careful care, he stressed.
"Dispersal is key for a number of reasons," he said. "Owls require a lot of food. It also spreads the gene pool out."
Glenshaw shares his owl experiences on his blog, forestparkowls.blogspot.com, where visitors can view photos and videos of the owls and their offspring.
He will also be the keynote speaker at the St. Louis Audubon Society's 2012 Awards Dinner, to be held Saturday, April 14, at Orlando Gardens in Marlborough. Reservation deadline is April 1. For details, visit www.stlouisaudubon.org.
For information on participating in an owl prowl with Glenshaw, or to contact him with an owl-related question, email him at email@example.com or visit his blog.