It’s that time of the year again, when the bugs and the deer discover all the tasty plants in my garden. While the Japanese beetles ravage the leaves of the apple trees and raspberries, the deer fawns chow down on the wildflowers. I don’t mind them, though, they are pretty cute, and very shy.
“Spike and the boys” — it’s not a new band, but a herd of White-tailed deer bucks that roam the backyard and beyond. There are three mature (big) bucks and three first-year bucks with tiny antler spikes protruding from their foreheads — hence “spikes”. They are browsing for anything edible in the backyard on this cold, snowy day.
Males lose 20-30 % of their body weight during the fall rut, as they follow the does around waiting for their opportunities to mate with them. That allows little time to eat, and consequently, they may enter the winter period of low food availability with less fat than they will eventually need to survive. Their winter browse on evergreens, leaves, and shrubs may not sustain them completely either, and they may continue to lose weight throughout the winter, despite trying to reduce their metabolism by being less active and lowering their body temperature and heart rate: lessons that the “spikes” will need to learn quickly.
The lyrics from California dreamin’ are running through my head this morning as I look out at our ever-present gray world: “all the leaves are brown (the ones still on the tree), and the sky is gray (for days on end)…”
And the weak sun screened behind the dense clouds doesn’t help much. This is the time of the winter solstice, the least daylight we’ll have this year. According to the experts that track these statistics, those of us at 45 degrees north latitude will have 8 hours and 46 minutes of dim light today, and the sun will rise only 21.5 degrees above the horizon at noon.
For comparison, that’s 6 hours, 51 minutes less light today than during the June solstice, when the sun rose to 68.5 degrees above the horizon at noon. Here’s what that difference in sun angle looks like in geometric space.
It’s no wonder that animals and humans alike just want to curl up and rest until the sun comes back out again.
The deer herd wandered through the backyard for the first time in quite a while. A few does, three bucks, and assorted youngsters of the year. Two of the bucks got into a couple of short shoving matches, primarily instigated by “big buck” (he of enormous girth photographed in mid-November). The rut might be mostly concluded, but there seems to be enough residual hormone circulating to ensure the male dominance hierarchy is still on-going in the herd.
Now we see the advantage of that larger, more complex rack on older bucks, with tines that can reach into the sensitive facial areas of their competitors. Of course, the added stature and muscle mass helps those big bucks push their smaller competition around as well. Thanks for the show, boys.
This guy is big! The biggest one I think I have seen near my backyard, anyway. He calmly strolled onto the neighbor’s lawn about 20 feet from their house, and plopped himself down on the lawn for a morning rest.
Not only are there multiple tines in his rack, but some are quite broad, meaning this guy took in a good measure of protein and minerals (e.g., calcium) in his summer diet while those antlers were developing. Maybe he discovered a nice vegetable plot with peas and beans, or a stash of acorns.
Males need a high protein (as much as 16% protein in younger animals), mineral-rich diet not just to grow antlers but to develop the protein and fat stores that will carry them through the energy-intensive rut season and the remainder of the winter. How much leafy green stuff would they have to chow down each day to take in that much protein?
That’s a trick question, because the protein they absorb doesn’t come directly from their food, but from the microbial fermentation products, and from digesting the microbes themselves, that deer and other ruminant herbivores raise in their complex, four-compartment stomachs. So, the better they feed their microbial friends, the more nutrients the microbes pass onto their deer hosts.
Males might lose as much as 30% of their body mass during the rut, depending on the level of competition and number of competitors they face, so gaining as much mass as possible during the summer is integral to their success and their survival.
I know I’m doing my part to sustain these guys, judging from the number of perennials in my garden that get munched down to their roots every summer.
Signs of fall are beginning to appear as a few maple trees show some red and gold color in their leaves, the squirrels are busy collecting nuts off the trees, Canada Geese fly in V-formation overhead, and a few of the wildlife start growing their winter coats. I first noticed the latter when the fawns suddenly appeared in the backyard without their spots.
What this tells me is that there have been at least two sets of twin fawns that have been eating up the backyard garden — and I thought it was just one hungry pair that had been doing all the damage.
The deer really like my backyard: they eat my plants, they bed down in the wildflower garden leaving big depressions in the vegetation, they rest right under the bird feeder, and believe it or not, the half-grown fawns chase the foxes right out of the yard. But I enjoy watching them parade through, so I just keep replanting the garden.
And where do these two learn where the best places to forage are?
Cave Creek ranch in the Chiricahua mountains near the New Mexico border is an idyllic haven for birders and hikers. The scenery is pretty incredible too.
Sycamores can grow to be giants, but occasionally a limb snaps off, and we find animals taking advantage of the nook created by the amputated limb.
Desert animals are often pale in comparison to others of their kind in other climates, as this Great Horned Owl is. But there is more to the story than just differences in color.
Animals in this part of the U.S. seem to be entirely different geographic races of their parent species, and the extent of differences in their DNA, their color, their song, and their behavior have led scientists to begin splitting the southwestern desert species off from their representatives in other parts of the U.S. and Mexico. That’s great for birders that like adding species to their life lists!
We met some new friends along the Cave Creek trail, but apparently our “old friends” may be new as well.
A light snow yesterday morning brought the local deer herd by the backyard to clean up all the spills under the bird feeders. First, a small group of does wandered through the yard, and then a couple of young bucks, who were too cool to feed on fallen bird seed but felt frisky enough to put on a shoving match instead.
Back in Minnesota once again, I looked out my porch windows and found three deer resting on the neighbor’s lawn. I assume this is the same doe and twin fawns that I saw perusing the flower beds in the backyard before I left town in August.