Saturday, December 29, 2012

RIP Dustmop...?

Just before the rush of final exams we had a spate of warm weather. I took that opportunity to get some work done in the back field. From atop the tractor I spied a patch of gray fur... it was a dead opossum. I figured it was the dustmop. She had been dead for sometime but that did not deter me from inspecting the carcass. After a cursory examination, I saw no obvious cause of death. I made a mental note to return shortly with camera in hand.
Opossum front foot
(Seneca Falls, NY 12/12)
But then finals week kicked in. Then the snow came. It wasn't until Christmas Eve that I found the time to walk back out to the spot and see if the dustmop was still lying there. By now we had ten inches of snow and I literally had to sweep my boots back and forth through the drifts in order to find her ("What did you do on Christmas Eve?", asked any sane person. "Oh, I crawled around looking for a frozen carcass of an opossum in order to take photos of its feet." said I).
 
 
 
It is a primitive characteristic to have five toes on a limb and the opossum has five on the front and back feet. Sometimes when I say that in class, I get push back from students. We don't like to think of ourselves as "primitive". But the word is not pejorative. Animals with fewer fingers and toes are more specialized. Think of horses with their single toe per limb. They are very good at what they do but do not have the generalizability that we have with our "primitive" hands. Ever get a text message from a horse? I rest my case....
 
The hind foot of the opossum never ceases to amaze me. Check out the opposable big toe. Note that it does not have a nail. This isn't the greatest of shots but the carcass was not cooperating very well.
 
Finally, let's have a quick look at the tail. Naked and semi-prehensile, it is unique in North America. There is no sign of frostbite at the tip so I think this is a young opossum (although we did have a very mild winter last year and perhaps this individual made it through without any freezer burn).
Opossum tail
I was saddened by the loss of the dustmop. Although I only wrote two entries of the opossum and skunk duo, I had literally hundreds of photos from that particular camera set. But it was Christmas Eve. Family was due in an hour and I still had presents to wrap. I trudged back to the house with my head down, concentrating on covering the distance quickly. It was then that I saw the fresh tracks...
 
Opossum trail in snow
(Seneca Falls, NY 12/12)
I knew right away that this was an opossum. Could THIS be dustmop? Was there more than one opossum visiting that carcass (I never photographed more than one at a time)? The tracks led for quite some distance and through deep and shallow snow, thus providing some great tracking opportunities. First, the trail as I initially found it in deep snow. Notice the relatively wide trail width or straddle along with the short legs (short legs are deduced by the belly drag in the trail). In our area, that usually means opossum or skunk. What sealed it as an opossum even at a distance was the numerous tail slaps in the snow. In the photo at right, you can see several tail marks close to the photographer (me) and to the left of the trail. Finally, notice that this animal is not direct registering. In other words, the front and rear feet are not landing in the same spot. Many animals direct register (I have also seen that described as perfect stepping) so this was a clue as well.
 
I was particularly pleased with this identification because I was not identifying tracks, I was identifying the trail. The snow was too deep here for me to make out much int he way of individual tracks. For me, this was a step forward (pun intended) in my journey as a tracker.
 
One more view of the tail slaps:
 
 
 
Opossum trail
(Seneca Falls, NY 12/12)
As the opossum moved into shallow snow, the tracks became more distinct, the belly drag was eliminated and the tail slaps became mere wisps in the powder. In addition, notice that the front and rear feet are ALMOST landing in exactly the same spot. I found that interesting since in the deeper snow, they were so far apart. Have you ever followed the tracks of someone else in deep snow? Its easier to step right where they stepped rather than making your own prints -- that is, unless they have a very different stride than you do. When I break the trail, I try to keep my strides a bit shorter so my wife and daughter will have an easier time following. I think the opossum with his short legs had a hard time in the deep snow even keeping up with his own trail and simply couldn't direct register easily. Last thing to note in this photo: direction of travel. I have learned from several trackers the adage "Long in, short out." Even if a trail is blown in with snow, you can tell the direction of travel because the feet make a long mark on the way in and a short mark on the way out. In this case, the opossum is moving away from the photographer. You can also see that in these wolf tracks from Yellowstone.
 
Here is one more shot in medium-depth snow. Note the tail marks. Moving to the right.
 
Finally, a shot in the shallowest snow I could find. When the opossum got to our backyard, it followed my ATV tracks for a while and went up the driveway and to the road. The two tracks are nearly next to each other, like two incorrect jigsaw puzzle pieces placed together out of frustration. The front foot is on the right and shows the typical sprawling star-like pattern that helps tell these feet from raccoons. The hind track has four toes pointing forward and the opposable big toe actually overlapping the palm pad of the front foot. These were the first distinctive tracks I had seen on the entire trail. I was pleased that I had confirmation of my identification. I wanted to continue on the trail, but a car was pulling into the driveway. My parents had arrived and I was pulled out of my adventure and back into Christmas Eve...

Tuesday, December 11, 2012

The dust mop and the powder puff II: CHIMERA


The uneasy truce between Powder Puff and Dust Mop described in my last post is holding. In fact, evidence shows that perhaps the relationship has been taken up a notch. Friendship? Bromance? Um, no. But have a look at the foggy photos below and tell me what you would call it:


This is the closest I have seen them. They are even on the same side of the carcass.
Opossum and skunk feeding at carcass
(Seneca Falls, NY 12/12)

Yeah, I'm not sensing total trust here....

Here is an interesting shot. The fanciest tail in all Didelphidom....
Opossum and skunk chimera

Are theses two getting chummy because they are more and more familiar with each other? Each day there is less and less food available on the carcass and each day they seem to tolerate each other more. But correlation doesn't mean causation. I am genuinely curious as to why these two were never photographed together at the start of this set and now I am photographing them more frequently together rather than apart. I don't know. But i do have one other variable to consider: There is a new actor in the night shift. A gray fox made a few tentative appearances and then got comfortable enough with the flash that he settled right into the carcass recently for some venison. Is the additional pressure of the new scavenger on the scene influencing the dust mop and powder puff's relationship? And what clever name can I give to this catish fox? These are the questions that keep me from grading papers tonight.....











Wednesday, December 5, 2012

The dust mop and the powder puff

Opening day of the regular deer season was November 17th. I found myself, as usual, at my Father's property. It is only the two of us now. The other regulars have all hung up their guns for the last time. So a day hunting typically plays out like this: We get up early and ride double on Dad's ATV out back. We fist bump and head to our different spots. The Van Niel's are tree stand hunters and there are several to choose from on Dad's 80 acres. We hunt for a few hours on our own and then I usually head over to Dad and join him for a bit longer and then we ride back to camp for lunch. After lunch, it may be a quick snooze before the evening hunt, dinner, and usually grading papers for me.

7 point buck
(Fremont, NY 11/12)
The only variation to the routine this year was checking several camera traps while working my way to Dad's treestand. Results will be the topic of a future post :) By the time I arrived at Dad's stand it was noon. It only took a moment to catch up on the events of the day, since neither of us had seen much. But as so often happens in a hunt, everything changes in an instant. I was still settling in when Dad grabbed my arm and whispered "Buck!". I froze. The ettiquite is simple: His stand, his deer. I ducked out of the way and caught a glimpse of the large bodied deer walking slowly across the field. One shot and it was over. Just like that. Dad has been hunting for over 50 years and still gets a thrill out of each hunt.

We paced the distance as we walked up on his buck. 193 yards. I snapped a few photos of my proud papa and then got down to the messy work. Truth is, I enjoy gutting a deer (or any animal for that matter). Besides being "The Eviscerator" I am also the butcher. But the reward is venison for us and a carcass for the camera trap.

I selected a location in our short hedgerow simply becuase it was close enough to the house to check easily. The carcass has been out for several weeks now and the cast of characters has not changed.

THE DAY SHIFT: The diurnal crew is all-avian. A murder of crows and a single red-tail hawk. I have up to seven crows in one frame but the one below is my favorite.




THE NIGHT SHIFT: The nocturnal crew is decidedly furrier and toothier. I call them the Dust Mop and the Powder Puff.

Dust Mop -- This was the first image of the opossum that I obtained and it was so unglamorous that I had to laugh. The poor opossum has quite the image problem already without me plastering unflattering photos all over the internet.


To be fair, let's have a look at a good hair day:
 
In fact, opossums can be downright cute if given the right light, a bloody carcass and an open mind:

Opossum on deer carcass
(Seneca Falls, NY 11/12)
Powder Puff -- My other nighttime visitor has more of a dramatic flair. This one knows how to make an entrance. Powder Puff makes the most of her assets and owns this carcass the moment she sets foot on the stage.

An unexpected benefit of the carcass is that Powder Puff is no longer tearing our lawn to shreds in search of grubs. This is clearly the same skunk from a previous post.

For weeks, the day and night shifts never crossed paths. No skunk or opossum photos in the day and obviously no crow or hawk photos at night. But in addition, the night shift and day shift didn't intermingle within their respective tours of duty. Not surprisingly, no photos of hawk and crow appeared and no photos of skunk and opossum were captured. But that changed recently. A few nights ago, numerous photos of Dust Mop and Powder Puff in what I would like to believe is a tentative detante.
Opossum and striped skunk
(Seneca Falls, NY 11/12)

Sunday, November 25, 2012

Bobcats return to the Finger Lakes Region of NY

I have been enjoying my camera traps for several years now and have been blogging about them for nearly two. But my fascination for them continues to grow. I have been toying with new sets lately and, as expected, have had mixed results. Not all new ideas are good ones. But it was an old fashioned hedgerow set this summer that produced my most unusual capture to date.

We had a group of middle-schoolers scheduled to visit our Muller Field Station this August for a day of outdoor adventure and a taste of science in the real world. I had set out some camera traps a few days earlier and to increase my chances of captures, I used some scent lures we had left over from a previous project. The field station is adjacent to a wetland and although we have only a narrow strip of forest along our old fields, we but up to almost two thousand acres of State-owned lowland ash-maple forest.

I gave the kids a brief introduction to camera traps (some were familiar with them from personal family use) and we predicted what animals we may capture given the habitat. Then it was time to check the cameras. I took them to the sets and explained at each one what my intention was. One was at the mouth of a culvert pipe, one was along a deer trail, etc. and the final camera was in the hedgerow closest to the buildings. I literally chose this location becuase it would bring us back around to the station along the easiest possible route. When we got back to the classroom, I pulled an SD card at random from my pocket without knowing which camera it came from.

Bobcat
(Richmand, NY 08/12)
And the very first photo from that very first card was the photo on the right: a BOBCAT! Well, half a bobcat. To say that I was excited is an understatement. Some of the middle-schoolers fed off my enthusiasm while others were more "Like, it's just a butt!". Well, yes, but it is the butt of a BOBCAT! Not only is a bobcat a pretty cool capture anyplace, it is particularly great here in the Finger Lakes because we are just getting a resident population back after many decades.

But that is news to some people. You see, sightings of bobcats have been much, much more common than the confirmed evidence would predict. Physical evidence of bobcats would most likely be road kill, camera trap photos and incidental captures in foothold traps. These forms of physical evidence have become increasingly more common in the Finger Lakes over the past ten years in particular. So why the "too-common" sightings? Misidentifications, of course. Feral cats are common and it is easy for someone to mistake a big feral cat with a bobcat.

Bobcat
(Richmond, NY 08/12)
It turns out I got two bobcat photos that day in August. The very next photo on the card was this one (left). The purplish color occurs when the light meter causes an incorrect exposure in low light conditions. It doesn't happen often but unfortunately it happened here. With the time stamps so close together, I have no reason to doubt that this was the same cat photographed earlier. I have to admit, the quality of the photos detracted some from the joy, but not much :)




The story isn't over yet. In September, I had my own students at the Muller Field Station for my Wetland Mammals class. Each group of students designes and implements a two-wwek field study with camera traps. This year, Stacy, Jeff and Adriel decided to compare wildlife crossing a beaver dam, a man-made bridge and a likely water route across the channel. The small iron bridge proved to be quite the highway for that two week period with red fox, gray squirrel, raccoon, BLACK BEAR and.... (wait for it)..... BOBCAT. And again there were two photos. This time, the pictures were from an IR camera, so they are black and white.



And a red fox for scale:


It turns out that this was the first confirmed bobcat in Honeoye Valley reported to the NYS DEC. What a thrill for my students and I. We were able to contribute a little to the natural history of this species. Leo Roth from the Rochester NY newspaper The Democrat and Chronicle did a story on it. And the timing of all this was perfect as the NYS Department of Environmental Conservation just released a new bobcat management plan for NY. You can find that plan here.

Looking forward to the next bobcat captures!

Thursday, November 15, 2012

Skunk diggings and droppings

Striped skunk
(Seneca Falls, NY 8/12)
"Did you tell your Father about the skunk?" Laura said over dinner the other night.
"Skunk? What skunk?" I said with a forkful of food poised at the ready. You see, this is the time of the semester that I challenge my introductory mammal students to a friendly game of "who can see the most mammal species and their sign". The checklist is displayed in the classroom and of course, the honor system is the rule of the land. I had yet to see a skunk, but apparently one was in the lawn the previous night when Danika got home and she stayed in her car for a few minutes to let it gain some distance before coming into the house. (At right is a photo I took earlier this summer)

Lawn damage from skunk
(Seneca Falls, NY 11/12)
I poked around the yard with a flashlight a little with no luck. But the next morning, I did some scouting and found that this guy has been busy in my yard for some time now. What you see in the photos are diggings made by a skunk to search for grubs and other invertebrates. Raccoons do this as well and I am not sure how to tell the difference. I am certain I read an account recently*, so i will have to search for it (and with the magic of electronic editing, amend this entry to make it look like I knew what I was talking about the whole time!). The photo to the left is a particularly deep hole. Note the penny for scale.
*AHA! I found reference I was thinking of. Elbroch's Mammal Track & Sign says (p. 698-99) that skunk digs are conical with the dirt thrown back only a short distance while raccoons have the debris pile farther from the hole.

Now, it is important for me to tell you that I am not a fanatic when it comes to lawn care. In fact, I am not much for yard work of any kind. I look at the digging as an interesting piece of natural history and perhaps a bit of soil aeration. There are several patches in both the front and back yards. Below is a photo that gives you an idea of the extent.



Skunk diggings for grubs
(Seneca Falls NY, 11/12)
 One more photo as I don't think these are showing up well (compensate for quality with quantity is the theory here...):
Skunk digging in lawn
(Seneca Falls NY, 11/12)
The skunk or skunks have left some scat behind as well:

The piles are similar to each other and I must admit that I would be hard pressed to call them skunk without the circumstantial evidence of the holes and the sightings. I checked the camera in the back yard and found this:
Striped skunk
(Seneca Falls, NY 11/12)

But a camera trap capture doesn't count. The sighting must be of a live animal. So last night I took the headlamp out again. This time I didn't make it 15 feet from the door before I could smell him. I heard some movement only 10 feet away and off he scurried! It appeared to be the same white-backed individual captured above. I watched as he waddled under my daughter's car. I have to remember to warn her.....





Sunday, November 11, 2012

Touch of gray

After about a year-long dry spell in regards to gray fox, I am getting photos on three different cameras. Even if this is one individual instead of several, I am happy for the results. I am under the weather today and not feeling chatty. But I have some nice images to share, so scroll through and enjoy.

This is probably the best photo. It seems that I have a very high percentage of gray foxes that have their heads turned away from the camera. Nice to see the face here...
Gray fox
(Seneca Falls, NY 11/12)
Two interesting photos of very different gaits. Look at the careful stride of this top photo compared to the longer pace of the lower photo. Sure wish there was snow on the ground to compare tracks.


Finally, I have a camera set on a mossy downed limb. It is an interesting set and I was intending it to be for rodents. One of my first images was this gray fox, right in the camera's face...
Gray fox walks on log
(Seneca Falls, NY 11/12)



Thursday, November 8, 2012

Flying squirrel and pumpkin guts

Since our daughter is too old to dress up for Halloween any more and our house is so rural that we don't get any trick-or-treaters at the door, the only tradition left is carving the pumpkins for the front porch. I must confess that I only participate in eating the roasted seeds after all the work is done. This year I saved a little of the pumpkin goo for camera trap bait. I finally remembered to take it out of the fridge and set it out early this week.

When I got to the camera set this evening, I was first excited to see that pile of pumpkin guts had been ravaged but then dismayed to see the camera askew and covered in mud. I sighed inwardly. Ten photos were registered, but how many of them would be blurred by a muddy lens? I trudged back to the house with the certainty that some critter had ruined another set...


Raccoon
(Seneca Falls, NY 11/12)
 The first few photos were incidental to the bait. An eastern cottontail hopped by. The neighbors cat made an appearance. And then the raccoon appeared. It doesn't seem to be honed in on the pumpkin at first. But with that nose to the ground, it won't take be long before it finds the prize.











Raccoon
(Seneca Falls, NY 11/12)
A minute later, the coon finds the bait. He spends a minute there and then heads back on his original track.













This was the last clear photo. "Clearly" this was the culprit. I have had coons climb my cameras before but this one really sent the camera at an angle. The camera was now pointed at some random spot on the ground rather than y precious pile of putrid pumpkin. Sigh....






Flying squirrel sp.
(Seneca Falls, NY 11/12)
Which is all to say that the next photo was all the sweeter for the luck involved. FLYING SQUIRREL!!! :) And I never would have gotten this capture without the coon tilting the camera (Look how far from center the pumpkin bait is now!). He posed nicely between the smudges of mud. I couldn't have asked for a better result from the pumpkin guts experiment. In a word: "gourdgeous"










Monday, October 29, 2012

The not-so-impressive white tails....

This has not been a typical camera trapping fall in regards to white-tailed deer. I have had dismal results on my property and not much better on my Father's. I have not had the number of overall deer I normally get nor am I getting the quantity or quality of bucks seen in past years.

Here is an interesting pair of photos taken about an hour apart. This first photo is of a deer with his first set of antlers. Since deer are born in the spring and data is collected from harvested deer in the fall, deer ages are usually given with an "and a half" added. For example, this deer is one and a half years old.

Yearling white-tailed deer
(Seneca Falls, NY 10/12)
Now take a look at the next deer to walk past the camera. He is sporting a much larger rack. Now that could be for a variety of reasons. He could have better genetics. He could have better nutrition. He could have both! But this guy is almost certainly just OLDER than the first deer. We can look at two clues in the antlers. One is the larger spread. Almost every single 1.5 year old buck has a rack that is inside his ear-spread. This second deer is not quite past the ear-spread either, but that is still common for 2.5 year old deer. The next clue to the age of a deer is the diameter of the antlers. Look at how much thinner the rack is above than the one below.

Two and a half year old buck
(Seneca Falls, NY 10/12)

Just one more year or two and that buck above will be a nice trophy. And that has been the theme this fall. Any photos of deer I have gotten, all show the promise for future seasons, but none look like the kind of buck I would like to harvest this year. The test for me always comes on some cold day when I find it hard to remember the last time I saw a deer and along comes a young buck. It is then that I feel torn between letting him walk and HOPING to see him again or killing him then and there and filling the freezer. In the last decade, I have let far more deer walk than I have shot. In the end, I do not regret that. There always seems to be venison from Dad, even when I don't find the buck I want to shoot. One last photo to share. A ten-point buck that I need to find next year....







Tuesday, October 16, 2012

Flying squirrel in action

I have spent so much time on this darn video that I have to keep the text short here. Earlier this month I blogged about a camera set I have in the back yard specifically for squirrels (read the original post here ). The Cuddeback Attack is pointed up a black walnut tree in our backyard and has produced slim results... until now. Last week brought an increase in gray squirrel activity on this tree and a new camera trap species for our property: flying squirrel! Check out the video. Nothing super special, but my first video of flying squirrel. Having on my home court is even sweeter.

Sunday, October 14, 2012

Out on a limb...

Sometimes I am reluctant to pronounce with authority what is happening in my camera trap photos (Going out on a limb so to speak). But this time, I feel I can safely say I have solved "The Mystery of the Barkless Branch". When I came upon the branch in question, my first thought was "This is the work of squirrels!" But I had never seen anything quite like it before. I have seen thinner branches stripped and I have seen smaller patches barked, but never have I seen such a large limb laid so bare. The second thing that gave me pause was this was a downed limb. By the looks of it, it seemed dead rather than a living branch ripped from a tree. So I was puzzled as to who did it and why. A camera trap was in order! Now, someplace on this laptop or in one of the dozen SD cards floating around my workspace are the photos that I took of that limb to show you good people the extent of the damage. I will add them if I ever find them.

Squirrel bite marks
(Stony Brook SP, NY)
As for WHY, I felt there were three options. First, it could be feeding. Squirrels and other rodents  (as well as rabbits) are known to "bark" trees for food. The prize is the tender cambium layer under the bark. Take your fingernail and score a young tree and you will easily find the green cambium layer. Second, this could be a marking behavior. As it so happens, I have been increasingly looking for squirrel bites after first learning of them in February. I wrote about woodchuck bites here. (and remember that woodchucks ARE squirrels). Here is what a typical squirrel bite looks like -->
Notice that it is a long stripe on the tree. The purpose of this biting seems to be to transfer scent from glands on the cheek rather than to feed. The bites themselves never make it all the way to the cambium layer. So what I was seeing on the branch in front of me was nothing like this. But I am no squirrel-marking expert so I was reluctant to eliminate any possibility. Finally, I felt it was possible that the bark was being collected as nesting or winter den material. The only flying squirrel nest I have ever seen was in a bluebird box and was completely made of shredded bark.

Look closely to see the individual incisor marks of the squirrels.
One last shot to give you an idea of how large this stripe is. According to Mark Elbroch, the squirrel bites are likely to be on the sheltered side as this one is -- they are taking advantage of the natural lean of the tree to keep the scent from being washed away too quickly.

As for the WHO, I had several suspects in mind. I was pretty confident this wasn't a bird, but I considered woodpeckers. However, the wood was really not compromised at all as one would expect from a woodpecker. That left mammals and more specifically rodents (this just wasn't the work of rabbits). I was thinking gray squirrel since the are bigger and this was some big damage and the woods were primarily deciduous; the prime habitat for gray squirrels. I remember thinking Eastern chipmunk as well and as it turns out we never got a single image of chippies.

So our game of clue was upon us. Was it Professor Pileated with the candlestick in the library? Or Ms, Squirrel in the kitchen with a lead pipe? Time would tell.....

Here are the results:

First, the most images obtained were of mice. I never saw the mice engaged in any behavior that would account for the damage. It appeared they were using the log as a highway. I made a single composite photo of several mice just for fun:

But the second most common critter was the red squirrel. I didn't really consider this prime red squirrel habitat so I didn't really think of him as a suspect, but perhaps that is exactly WHY he was eating bark. In prime habitat, the red squirrel is eating pine seeds. I am under the impression that bark eating in squirrels is a sign that there is not enough of their preferred food. We had a very poor beech nut and acorn crop this year so maybe that had something to do with this behavior as well.
Red Squirrel
(Wayland, NY 10/12)
I have done this once before but here is a composite image of a gray and red squirrel so you can easily compare their sizes.
Red and gray squirrel compared
(Wayland, NY 10/12)
But its the video that really helps tell the story of what is happening: