The Second Life of a Dead Owl

The dead screech owl lay beneath a conifer in the yard; but it hadn’t been dead long. It was in full rigor mortis which, in an animal this size and depending on temperature, usually begins an hour or less after death and lasts less than 24 hours. The bird appeared to have a broken right wing which drooped somewhat loosely.

Rather than burying the bird, I decided to set a  camera trap to capture photos of the scavengers that came for a meal. During the first 24 hours the camera was in place, nothing fed on the carcass. The next night an opossum visited and a series of photographs showed that it ate part of the owl.

The next night a gray fox arrived –

And the fox marked the spot as its own –

The fox visited repeatedly over the next week, eating some of the screech owl on numerous occasions.

At about the same time a wandering house cat stopped by; but there was only a single photograph of it so it apparently didn’t stay long.

Other visitors to the remains were an eastern chipmunk, which came on the eighth day –

And a gray squirrel, or squirrels, that visited repeatedly –

Rodents like the chipmunk and squirrel regularly gnaw on bones for the calcium they contain. What many people don’t realize is that these rodents also eat meat and frequently kill and eat nestling birds and smaller mammals.

The last visitor before the camera was removed was a gray fox that came on the 17^th day –

By that time, the only discernible remains of the screech owl were several of the long primary wing feathers. The fox must have been attracted by the residual scent because there was nothing left to eat.

The Best Laid Plans

In the road in front of the house lay a dead gray squirrel, one of the innumerable wild creatures killed by vehicles each year. 

 

Its death presented an opportunity for some camera trap videos. So I took the recently demised up the hill above the house and lay it down in front of one of my camera traps.

I’d done the same with a dead screech owl a few years ago with the resultant still images presented in this post.

As with the screech owl, I used a large steel spike to pin the carcass to the ground. Hopefully the spike would prevent some animal or bird from quickly making off with the remains.

Here are the videos –

The gray fox was quite tentative as it approached the squirrel: perhaps because of the camera trap’s infra-red light, perhaps because that’s how gray fox approach prey that’s rather large and might fight back, perhaps because that's how gray fox approach carrion.

Mated gray fox pairs often hunt together which may account for a fox appearing in clips after the squirrel had been carried off, or perhaps it’s the original fox come back for anything it missed.

The opossum missed a meal, beaten to it by the gray fox. Maybe next time the opossum will get what it was looking for.

The same goes for my plan to get multiple species feeding on the dead squirrel – maybe next time.

Owl Box

There are seven species of owls that regularly occur at various times of year in northcentral Pennsylvania: great horned, barred, barn, long-eared, eastern screech, saw-whet and short-eared. Even the short-eared owl breeds here, but only at two sites; most shortys come south in winter in search of food.

There's usually also an influx of saw-whets during the winter as northern birds come south in search of the small rodents on which they feed. We occasionally get one or more snowy owls during the winter when they drift south from the arctic.

Of the seven species that are regularly found here, the short-eared owl and barred owl are my favorites – probably because those are the owls I see most often. Short-eared owls are open-country birds, hunting and nesting in hayfields and marshes. Barred owls are birds of the woodlands, preferring cavities in large trees for nesting and roosting.

The many acres of the forests surrounding our son and daughter-in-law’s place is suitable habitat for barred owls –

But those woodlands don't have an abundance of large trees containing cavities.

So, having a stack of used lumber in the garage, it was time for me to make a nesting/roosting box suitable for a barred owl. Plans for these boxes are readily available – here’s one from the Minnesota DNR’s Woodcrafting for Wildlife –

The wood I had was what’s sold as spruce-pine-fir, not at all decay resistant; I used some scraps of drip edge and left over shingles to help keep rain and snow off the roof, and modified the plan to create a slanted roof to shed rain more effectively. These modifications should help the box last longer –

A branch was fastened to the front of the box because young owls do what is called “branching”. The owlets leave the nest before they can fly and spend several weeks clambering on tree branches; the parents continue to feed them until the owlets get stronger and learn to fly.

We went north for a visit and one fine day our son, who has a wealth of climbing experience, went up a sugar maple to install the owl box –

Hopefully, a barred owl will find the box suitable and raise some owlets in the cozy abode.

Late Summer in the Hollow

As summer ended it was time to check the card in the camera trap in the hollow. The latter half of July was extremely dry as was the entire month of August. Nonetheless, there was a good variety of wildlife appearing in the videos –

The second buck has what are called cutaneous fibromas on its face that appear as dark lumps. These fibromas are caused by a virus and don’t actually injure the deer, nor does the virus affect other mammals, including humans.

It’s quite possible that the screech owl caught one of the flying squirrels and made a meal of it. Although barred owls frequently prey on flying squirrels, it’s not unheard of for screech owls to do the same.

             *************************************************************

There will be no more videos from the running log. I’d moved the camera further from the log where it captured several short videos of deer, and then …

… and then the landowner sold timber from part of the property and the loggers opened up the old road spanned by the running log to use as a skid trail –

Good-bye running log, you were a good place for a camera trap.

Dinner is Served

Down at the edge of the wetland lay the carcass of a white-tail buck, nearby was a crossbow bolt (arrow), a good clue to the cause of its demise. The deer was probably wounded during the late archery hunting season which ended in January. Wounded deer, especially those hit in the abdomen, frequently head for water. The hunter never found the deer so there it lay.

Poachers frequently use crossbows since they’re silent and quite accurate, so the deer could have been wounded by a poacher working after dark. In that case there was almost certainly no effort made to find the deer.

When I found the carcass it had already been fed upon by scavengers – eastern coyote, bald eagle, vultures or …?

Another great opportunity to get videos of whatever was feeding on the carcass. As usual in an area without trees I mounted the camera on what is called a concrete stake, a half inch diameter steel rod three feet long with a series of holes along its length. These are usually used to hold concrete forms in place, but they’re also excellent for holding a camera trap.

With the camera trap in place there was nothing to do but wait for a week or so and then check the videos it obtained. The first week the camera had well over a hundred videos of vegetation blowing in the wind – but it also had many videos taken over several nights of a red fox feeding on the carcass –

Most predators will feed on the carcass of a dead animal or bird. Less energy is expended in feeding on something that's already dead and there’s much less risk of injury for the predator – an injured predator is at a distinct disadvantage in catching prey.

Over the years In Forest and Field has had a number of posts showing the creatures that have fed on the carcasses of a black bear, white-tailed deer, raccoon and screech owl.

The plan is for the camera trap to remain in place until the deer has been reduced to scattered bones and hair – bones that will be gnawed upon by rodents, hair that will grace nests of birds and rodents.

Winter in the Hollow

A bit over 50 years ago, when they were newlyweds, friends of ours bought an old hill farm of about 50 acres. The roof on the house leaked with every rain and the water supply was piped from a spring up the hill. The spring is the origin of a small stream that flows through a narrow valley of the kind that’s called a “hollow” around here.

In an aerial photo from 1938 there are only a few trees in much of the hollow, apparently it was used as pasture when the property was farmed.

The farmer that cleared the hollow hoped his cows would squeeze a bit of nutrition from whatever would grow on the shallow acidic soil. The hollow is the kind of place that should have been left as woodland rather than being cleared of trees: the slopes are steep, the soil shallow and the stream at the bottom would have carried a load of silt with every rain.

It’s been a long time since the hollow was pastured, since then trees have been growing on the slopes and along the stream. Now the entire hollow is wooded although the trees are fairly small and grow slowly on the shallow infertile soils. The hollow is once again habitat for wildlife and wildflowers.

For several years I’ve had a camera trap in the hollow to document the wildlife that spends time there. This past winter the camera was one that took videos. Here’s a selection of those videos in the order in which they were taken –

In addition to white-tailed deer (including four young bucks still bearing antlers in mid-February), these are the species in the video: striped skunk, weasel (probably a long-tailed weasel), gray squirrel, screech owl, eastern coyote, red fox, raccoon, cottontail rabbit, and gray fox.