Can the eating habits of whitetails impact the composition of a forest?
It’s no secret that white-tailed deer prefer to eat some plants over others.
They’ll munch on white oak seedlings all day without ever touching striped maple, given the choice, for example.
Foresters have long said that can shape the woods of tomorrow. It’s why they fence some regenerating timber cuts, to keep deer from eating the species they most want to grow.
But now there’s this.
Researchers from Penn State University say the browsing habits of picky deer might actually be promoting the spread of some invasive species.
The scientists simultaneously offered captive whitetails at the university’s deer research center eight nonnative invasives and seven native plants to eat. The food was placed out in containers, and daytime and nighttime motion cameras recorded which animals ate what. The amount of each type of vegetation eaten was also measured.
Monitored were eight adult does and their fawns over late summer, early fall and spring.
The deer ate more native species than not.
But they didn’t eat them alone.
According to the research, while deer consistently avoided several invasive species, namely garlic mustard, Japanese barberry and Japanese stiltgrass, they feasted on a few of others, including Oriental bittersweet, European privet and Morrow’s honeysuckle.
They seemed to prefer those latter species as much as they did native red maple, even.
Meanwhile, they turned up their noses at what scientists called a “native invader,” the hay-scented fern.
What’s it all mean?
“To the extent” that any herbivore shapes the look of a forest community, deer – with particular feeding preferences – might be playing a role in the spread of invasive species, said Penn State weed ecology professor David Mortensen.
That’s true perhaps even when they’re willing to eat them.
Lead study author Kristine Averill said some invasive plants that deer seemed to highly prefer are increasing in abundance in natural areas. That pattern may be exacerbated by the deer because these plants produce fleshy fruits that deer eat, and then the seeds of the plant are spread in their feces, she said.
