As a child, the idea of actually seeing a wild deer was exciting, but improbable. I was a city kid, and though we often joined a local club for hikes in southern Indiana, I don’t remember even seeing tracks very often. And I certainly never imagined that one day there would be herds of deer in the city that I could watch every day. In less than 40 years, Whitetails have morphed into a fast multiplying garden nuisance and road hazard. And as usual there isn’t one single reason, but a convergence of ecological and cultural changes.
Number one, no surprise, is an increase in food. Despite the fact that suburban sprawl has reduced forest cover, it has actually improved the whitetail diet. The quote below explains this better than I could:
“Deer populations forty years ago rarely grew large for the simple reason that most of the trees in an undisturbed forest are old, and only the undergrowth provides suitable food. It is because land development usually involves clearing land that urban development leads to increased deer food supplies. There are far fewer trees, but the trees are new growth, and very munchable. So are garden shrubs. Deer eat very, very well in surburbia. Many residential areas are reporting as many as 200 deer per square mile, three times what a forest will support.”
Read the rest of this great post at: http://biologywriter.com/on-science/articles/deerpops/
The pic below is a deer exclosure in our little forest, one of several erected a few years ago by Dr. Robert Kingsolver and his students at Bellarmine University. The purpose was to collect data on the impact of deer browsing, by comparing what’s able to grow inside with the surrounding landscape. I wonder if they’ve been back to see, because the results are quite revealing – and amusing! What’s visible in this exclosure is a lush growth of the common exotic groundcover/vine Wintercreeper, Euonymus fortunei. It’s outside the fence too, but there it is obviously being browsed heavily; in fact a deer has even bedded next to the fence. Though I’ve observed for a number of years that Wintercreeper is an important deer winter food, I didn’t have such excellent evidence till now.
I’m sorry if the next pic grosses you out, but I think it’s quite interesting (I have been accused of being overly interested in pellets and other scat.) It’s a fresh deer dropping, too moist to be called a pellet – the result of browsing on mostly Wintercreeper (in fact the plant is visible at the top of the frame.) These very wet droppings are usually found only in winter, and show how much deer in our forest rely on this plant.
All Euonymus are “highly preferred” by whitetails, and apparently have good nutritional value – deer farmers in NZ offer Wintercreeper as part of the winter diet.
More typical looking pellets in the pic below, again deposited in an area with Wintercreeper. This plant now occurs in most of the preserve as a groundcover, sometimes in very dense patches that exclude other vegetation. It was first observed here less than 25 years ago, and has spread in two ways – by expansion of the primary patches, and by climbing trees, then fruiting and being eaten by birds. It does seem amazing that this single plant can provide such a reliable, if rather monotonous, deer winter diet. But if they’re craving variety, our forest’s whitetails can always visit the neighbor’s yards.
So the deer in this forest are not going hungry in winter. But the pic below is what I discovered down the hill from the Louisville Nature Center last week. I was alerted by an odd daily gathering of deer at this spot, just out of sight behind a fallen log. The 50 pound sacks had been lugged in by a well-meaning former deer hunter, who I met coincidentally as I was trying to drag them out! The corn was already half gone – obviously more popular than the pellet feed, but it may not have helped much nutritionally. A Whitetail’s intestinal flora changes with seasonal food sources – when their gut is adapted for wintertime low energy browse, high-carb foods like corn can be indigestible and even cause rumen acidosis, a life-threatening condition.
Today I saw this family group browsing in a wintercreeper patch, with just the tips of the vines sticking up from the snow.
Despite the fact that our growing deer herd is undoubtedly having a damaging effect on the native flora in this forest (Feb.3 Life is hard for young trees), I really enjoy watching and learning about them. They’ve come to tolerate me at pretty close range; I’m that odd human that hangs around a lot, but doesn’t seem to be dangerous.
With large dark eyes and graceful bodies, they’re beautiful by human standards, and I suppose that’s why their increasing numbers are tolerated in suburbia. Just imagine the outcry if coyotes were this abundant – despite the fact that overall, coyotes are likely more more helpful for urban ecosystems. Blame the “Bambi Effect” – this one movie has likely had more effect on public attitudes toward deer than any other single factor. I looked into the Bambi story for this post and discovered that the movie deviated significantly (no surprise) from the book. Bambi, a Life in the Woods, originally published in Austria as Bambi: Eine Lebensgeschichte aus dem Walde is a 1923 Austrian novel written by Felix Salten. The original story was darker and more environmentally “accurate”, yet still portrayed man as the evil hunter.
Of course, in urban and suburban areas hunting is either prohibited, or permitted only with many restrictions (though there’s some poaching). The deer in our urban forest will likely never need to worry about hunters. The worst they’ve got to deal with are fawn-snatching coyotes and getting hit by a car, and neither is enough to slow their upward population trajectory. The statistics from deer tags in Jefferson County over three decades show how numbers have grown: 24 deer taken in 1983, 712 deer taken in 1993, 860 deer taken in 2003, and 1,375 deer taken in 2013.
The majority of Whitetails in our forest are young, another sign of an increasing population. The abundant fawns and yearlings look especially shaggy in their winter coats.
Other things to see in a forest over-run with deer…
Maybe for young people growing up now, seeing deer all over the place just seems ordinary, but it never will be for me. Though I hang out with this little herd almost every day, it’s still a marvel to me that they’re here at all. It’s a marvel how they slip casually through the urban wilds; adapting effortlessly to a new landscape that might as well have been made for them.