Advanced Ecology Lab Week 1: Deploying Camera Traps

Students enrolled in Advanced Ecology this semester are sort of guinea pigs.

Teaching this class for the first time in the spring has resulted in many challenges already (and we're only in the first few weeks of the semester)....although none have been insurmountable so far.

The biggest challenge is: what does one do with college students enrolled in a spring-semester ecology course for their laboratory exercises?  This course has traditionally not been taught in the spring here, due to the cold and snow, which makes outdoor laboartories alittle challenging.  Well, there are a variety of indoor labs related to ecological concepts that have been designed  (grabbing different sized bolts and screws to demonstrate optimal foraging theory and etc.)....all of which work well, I'm told, and are pretty fun. Yet...these types of labs are not really my style (not saying they aren't probably cool, though).  So, I thought and thought about this whole thing for a long time.  Do I have them do some relatively safe indoor labs, that will probably be informative....or do a risk outdoor labs in the winter with unpredictable weather, and mostly new untested lab exercises....but with the potential to give the students some very cool applied field experiences?  Finally, I came to the realization that I'm a field biologist. As such, it just wouldn't feel right if I wasn't dragging these kids through the cold and snow.

So, that's what we're doing.

We have been given access to a bit of property not far from campus, and the students have been charged with a task associated with a hypothetical situation.  The hypothetical is as follows:  landowners would like to develop the property we are working on. However, due to its proximity to a protected natural area, our state regulatory agency is requiring some assessments be done prior to granting development of the site.  Therefore, the students have been "hired" to conduct a battery of ecological assessments of this property and write a thorough report of their findings that will be submitted to the regulatory agency (i.e. me).  Included in their report must be recommendations on whether the land is valuable both (a) as its own entity and (b) in the context of the landscape.

Will everything I have planned work throughout the semester?  I dunno...  In theory, yes. 

But, if these assessments don't all work....well....that's field work, and also a great lesson.  It's a great bit of reality for young ecologists to experience adversity.  In fact, overcoming adversity and learning to roll with it when things DON'T work is probably as important a skill for young field ecologists to learn as anything!

Week 1:  Site Reconnaisance and Camera Deployment. 

Due to the cold weather and potential for snow, we have to focus on mammals early in the semester.  So...we eased into things with a relatively simple task: a reconnaisance of the site we'd be working and student groups selecting sties to deploy camera traps. 

Three groups of students each chose locations for two cameras......so six cameras total.

One of their locations had to be in a woodland ......

....and one in the "grassland" or savannah on-site.

Then, they grabbed a GPS reading of the location.....

So, the cameras will be checked every week for a couple of months in addition to the other lab exercises the students will have to complete.  I'll hopefully post some hard data from our results in the future. 

But..I'll post cool pictures here and there.....we did get a few neat shots during the first week already (although they are basically all of White-tailed Deer).

Anyways, here's a smattering of examples, such as......

The close-up....

The follow-up....

The Shake....

The "move"....

The swinging hang-out spot....

And....El Diablo....

Also got Red Fox, Coyote and Raccoon passes, but the pictures weren't good enough quality to post them.

Subnivean Passageways

We've had a massive warm-up 'round here, reaching into the 50s today (unheard of for January!).

Needless to say, the deeper snow we once had is now melting. 

One morning last week, as I took the dog out for his first bodily evacuation, I found that the snow melt had revealed the activity of rodents.



Subnivean is a term for the area of interface between the ground and the snow resting on top of it (whereas nivean refers to the entire environment from the surface of the snow to the surface of the ground).  Some of us Homo sapiens are of the mind that snow is just all cold...and nothing could possibly live below its surface unless it was hibernating in a burrow. 

Not true!

Snow as an insulator:  The thermal conductivity of snow (or any substance) can be defined as the ability of heat to move through it (in this case, the ability of heat to move through the snow pack).  According to Halfpenny and Ozanne (1989), snow has a low thermal conductivity, making it a good insulator.  This is particularly true of dry snow, and once snow becomes wet or begins to melt, its thermal conductivity raises. Thus, the insulative properties of snow are related to how fresh and dry it is (Marchand 1987).  The snow's ability to insulate also has to do with depth of snowpack.  For example, 20 cm of newly fallen snow experiences little subnivean temperature variation.  However, as the ice crystals that comprise snow change in shape (as they melt slightly and refreeze over time, etc.), the insulative capacity decreases.  On the other hand, once snow reaches a depth of 50 cm, the "temperature of the subnivean environment is almost constant" (Marchand 1987).  At that point, its freshness apparently plays less of a role (Marchand 1987).  Snow also shows a variable thermal profile from the surface of the snow to the ground beneath.....generally being warmer near the ground than near the surface (Halfpenny and Ozanne 1987).  Furthermore, air exists between the ice crystals, etc., so there's no risk of suffocation. 

All of this is good news for the little rodents that like to construct these passageways through the subnivean environment.  They are insulated from the cold and wind, while the snow also shields them from the sharp-eyed hawk...the fox...the coyote (all of which prey upon rodents and are present on-site). 

But a good thing can't last forever. 

As the snow melts, their passageways are revealed, and they are without their subnivean highways until the next snowfall.

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I'm not entirely certain who made the tunnels in these pictures, but likely candidates include the white-footed mouse (Peromyscus leucopus), which I know is on-site, and the meadow vole (Microtus pennsylvanicus).  These passages were along the edge of a pine stand that borders an open hillside and the trails seemed to move between trees....so I'm guessing it's a White-Footed Mouse, which has a tendency to climb....

The snow has all since melted.

Personally, I'd like to see some more before the winter turns to spring.
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Literature Cited

Halfpenny, J.C., and R.D. Ozanne. 1989. Winter: an ecological handbook. Johnson Publishing Company.

Marchand, P.J. 1987. Life in the Cold: an introduction to winter ecology. University Press of New England. 

Winter Tracking Opportunities & Mammal Systematics.....

One of the great things about winter is that it provides lots of tracking opportunities.

We finally got some snow here this January.  December had been, basically, snow-less....which was sort of a disappointment.  However, the new winter wonderland this month gave me a chance to get outside with my daughter and follow some of the trails in the woods just behind the house.

Basically, all of these tracking opportunities near the house involve the ubiquitous white-tailed deer, but that's alright...especially when your with a three year old that can't walk too far from the back porch in her giant puffy snow suit.

Last week, the snow in the orchard near our house was a criss-cross of deer trails, all varying in their "freshness".  They lead off in several directions, but most followed a specific pathway through the woods behind the house.  One these trails looked is if it had been made recently.  It branched off of the main corridor and moved through the rows of planted pinetrees along the border of the orchard. 

Above: the main deer trail I decided to follow.

So in the amount of time I had available (dictated by my tracking partner), this easy (and very obvious) trail seemed like a good one to follow.  From what I could tell, the tracks looked like they had been made by a male, but I couldn't be certain.  They were of a decent size with very obvious dew claw imprints on many of the tracks I found.

Above, one of the tracks that actually showed up OK in the deep snow!

The trail wandered along a lane next to the pine rows and stopped to paw at an area in the snow that I had identified as a buck "scrape" during the rut this last fall.  Here it stopped and stamped around, pawing at the old scrape for a bit, perhaps hoping to catch a whiff of some useful information.  This may have also been another spot where a deer previously laid down for the night and another came along later and pawed at it....hard to know for sure.

Above 2 pics: two shots of the old scrape this deer had cleared off (close up shot below, further back vantage above).

It then took a few steps and deposited a little bit of fresh scat.  A signal to others?  It wasn't left on top of the scrape it had been stomping at, but nearby, so I'm not sure.  It may have just been "time to go", if you know what I mean. 

It also took an opportunity to peel some bark off of a few small trees......

Above 2 pics: Two great example of a scrape made by a white-tailed deer's incisors as it stripped bark from this little tree

Most members of the Order Artiodactyla* have no upper incisors.... only lower incisors.  Extant global Families listed by Mathee et al. (2001) within this Order include:

• Family Camelidae (the camels)
• Family Suidae (the pigs)
• Family Tayassuidae (the peccaries)
• Family Hippopotamidae (hippos)
• Fmily Tragulidae (the small "mouse deers" or chevrotains)
• Family Moschidae ("musk deer")
• Family Cervidae (deer/elk/moose, etc.)
• Family Bovidae (cattle, buffalo, sheep, etc.)
• Family Antilocapridae (pronghorns)
• Family Giraffidae (Giraffes)

Cetaceans (Dolphins, Whales, Porpoises) as a group are also positioned somewhere in the Order Artiodactyla, but listed as a "Clade"....I think.  The Clade Cetacea has its own list of families (such as Family Balaenidae for baleen whales, etc.).  Cetaceans are apparently most closely related to the Hippos among any of the extant Artiodactyls (Gatesy 1997; Price et al. 2005).  There may have been updates to this that have occurred since Price et al. did their work.  Mammalian phylogenetics can be pretty confusing these days.  I'm not as up on my mammal systematics as I should be I suppose.

Regardles of the systematics.......of these Families within Artiodactyla, only the pigs, the peccaries, the hippos, and the Cetaceans have upper incisors.  The rest, such as the deer/elk/moose, etc. (Family Cervidae), Pronghorn (Family Antilocapridae), and the cows/sheep/bison, and so on, all have no upper incisor..but ONLY lower incisors.

Yet, these lower incisors are used to great effect when stripping bark off of trees.  They can take those very sharp teeth on the lower jaw and run them up underneath the bark of a tree (especially a young tree).   They then scrape with an upward movement of their head and strip the bark off for quick meal.  You can actually see the incisor marks in the first picture above.
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After following the trail a short while longer, I came across an area where the deer decided to rest for the night.  It was a perfect spot.  Located below some large pine boughs, so protected from further snowfall and wind.  The location was also positioned on a slight incline, looking down over the orchard to the south.  A great vantage point to see, hear and smell what might be coming up the hill towards him.

Above: the "lay" that this deer made when he decided to bed down below some pine boughs for the night.

And then...finally....my daughter had had enough tromping through the snow, and we started heading towards the back deck.

But, it's nice to have these little opportunities from time to time..........
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* Cetartiodactyla is apparently an alternative Order name that has been proposed for Artiodactyla (Price et al. 2005).  I've seen it a few times....and I'm not fully certain if it's accepted yet or not?  Maybe someone can enlighten me.

Literature Cited

Gatesy, J. 1997. More DNA support for a Cetacea/Hippopotamidae clade: the blood-clotting protein gene gamma-fibrinogen.  Molecular Biology & Evolution. 14:537-543.

Matthee, C.A., J.D. Burzlaff, J.F. Taylor, and S.K. Davis. 2001. Mining the mammalian genome for Artiodactyl systematics.  Systematic Biology 50:367-390.

Price, S.A., O.R.P. Bininda-Emonds, and J.L. Gittleman. 2005. A complete phylogeny of the whales, dolphins and even-toed hoofed mammals (Cetartiodactyla). Biological Reviews 80:445-473.

Getting Rid of the Winter Blues



The key, in this case, is to have an annual ice-fishing trip with high school buddies in northern Wisconsin.

We've been taking this ice fishing trip since 2004 and it always falls on the same weekend (the weekend of Martin Luther King, Jr. Day).  Fortunately for us, we have access to a cabin owned by the father of a friend of ours (Nate). 

Usually a smallish group of individuals go along, and we exert alot of effort putting out and checking tip-ups (for those of you not familiar with a tip-up, stay tuned and I will explain).  It's not all hard work, though.  We also try to put forth considerable effort sitting in the cabin playing cards and reminiscing.  Or maybe just enjoying the incredible crisp, cold weather that is normal of a January in Wisconsin. 

So, anyways....we arrived on Friday evening and unloaded the gear, including the tip-ups.  These are a fishing apparatus designed so that a spool of fishing line and a hook can be placed below the ice (see pics below).  Bait is attached to the hook and when something strikes the bait, the spool moves, which causes a flag to pop up. Thus, a flag that has popped means you may have a fish.

The prep-work for ice fishing is substantial.  First, you have to give all of your tip-ups a good once over (new line, hooks, sinkers, etc.).  The evening that we arrived, Nate began the tedious process of preparing all of the tip-ups for deployment the next morning on the ice. 

Above: Nate preparing the gear for early-morning deployment

Early the next morning, we got dressed and trudged our mountains of gear out onto the ice.  To fish through the ice, one obviously needs to make a hole.  This is done with an auger and we were fortunate enough to have a gas-powered auger available to speed up the process (there was roughly a foot of ice to contend with in most cases).

Because of all the hard-work required, it's okay to take a break from time to time.  It's supposed to be an enjoyable experience, afterall!

Above: Justin and Chad show us how to relax on the ice while deploying tip-ups.

The result is a nice hole for your tip-up to rest on.

Once the holes are popped, any ice/snow that falls in must be scooped out.

Next, the tip-up gets carefully placed over the hole in the ice.....

Of course, it's always helpful to have a nice fire nearby to warm your chilled bones......

...or perhaps a cabin to step into for lunch and a drink....

If you're lucky, all of the hard work pays off and you get to have fresh fish for dinner....

Above: Nate and Andy give a lesson in how to haul in the big one through the ice.

Above two pictures:  A pair of Walley (Sander=Stizostedion vitreum) caught on tip-ups 

Above: Northern Pike (Esox lucius) is another species we commonly catch on this lake

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There's also usually a treasure-chest of tracking opportunities thanks to the snow.  There had been a nice snow-fall the night before we arrived, so I found a number of fresh tracks and trails to follow.  The snow was alittle deep, however, and good photos were hard to come by.  In the past, I've seen gray wolf (Canis lupus) tracks near the cabin.  None this time, however.  Yet, the usual cast of characters could be found: White-tailed Deer (Odocoileus virginianus), Squirrel (based on size, I'm assuming eastern Gray Squirrel; Sciurus carolinensis), and Eastern Cottontail (Sylvilagus floridanus).

Fox (I'm assuming Red Fox; Vulpes vulpes) were also present and always fun to track.  On more than one occasion, we crossed the trail of an individual who wandered across the ice on both sides of the peninsula.  This one moved with a purpose and took advantage of trails in the snow left by folks on snow-mobiles. 

Something also stopped by and made a meal of a bait minnow someone dropped on the ice. 

This could have been done by a bird, such as a crow.  The spattering of frozen blood almost seems unlikely for a fox, which I would assume would chew this up and swallow quickly.  A crow would hack away at a frozen minnow, making the scene above.  However, we never noticed any crows on the ice near our tip-ups.  It's possible that a fox chomping a frozen minnow would have spattered a bit of blood on the snow.....especially if that minnow was frozen to the snow and the fox and to work to get it out.

Just not 100% positive....At any length, the remains of the macerated minnow were right next to the fox trail I found.

More evidence of wildlife activity below.  The drillings of a woodpecker and based on the size, I'd say it was a Pileated Woodpecker (Dryocopus pileatus).  We saw them fly overhead on two separate mornings and they are incredible critters.

Another one I'm not 100% positive on.....an example of a raised-leg urination (or RLU) from a canid.  This was along the road near the cabin.  The tracks associated with this were fairly large and looked like a domestic dog, but I couldn't be certain.  Unfortunately, this individual didn't make it past our road-side camera trap (see below).

There were also a few large Canid tracks on the ice.  They measured around 3.5 inches from tip of the nails to the back of the inter-digital pad.  They followed the edge of the lake, investigating the shoreline, and at first I was excited that they might be wolf tracks.  It was hard to see the details of the print in the deep fluffy snow, but they didn't jump out as domestic dog. The top pictture below doesn't show details well, but you can at least see the general size of the tracks.  It's almost a double-register (i.e., the hind foot just about registers directly on top of the front foot).  Yet, it's not quite a double-register so the track looks a tad longer in the picture than it really is.  The bottom picture (with the tape measure) gives a better relation to size and detail. 



We followed the trail for a while, but eventually ran into some fresh human tracks running parallel to the Canid tracks......probably a domestic dog and it's owner.  Big dog, though!

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Of course, while I was there...I decided to throw out some camera traps and have alittle fun.  The cabin we were using was on a peninsula, so there was limited human activity in the surrounding area, and the threat of theft was reduced.  I figured it would be easy to put a few cams out with less rigid security measures in place.  I also knew from the wildlife activity I had observed in the past, there was the possibility for some neat pictures.  However, time was working against me....... the cameras could only be out for 2-3 nights.  I was hopeful, but also realistic.  I also decided to help the process along, if possible.  I'm not one to put alot of bait out in front of my cameras, but in this case I pulled out all of the stops due to the short time-frame.

Above: a bog that borders the lake we fished on is a great place to find evidence of wildlife

We had found several trails that appeared very much like that of a weasel.  They made the classic "dumbell"-shaped 2-2 pattern that Rezendez and Halfpenny talk about in their tracking books.  They also appeared to wander back and forth, checking every possible nook and cranny for food.  For some reason, I never took a picture of the trails....but they prompted me to set up a baited camera trap.

The trail lead to the root system of a blown-over tree, and it came in and out of this root system several times.  Looked like a good place to put up a camera to me.

Above: the root system burrow that I saw the apparent weasel tracks enter.

Above: hanging the camera next to the root system.

The view from the camera is below...the blown over tree is to the right just out of view.  You can see the small pile of bait minnows......  I also put a dab of commercial trapper lure for weasels on a stick poking out of the snow just left of the bait pile.

The weasel I was hoping for never showed, unfortunately.  Instead, I got pictures of an Eastern Cottontail......

....and two visits by a Red Squirrel (Tamiasciurus hudsonicus).

Although it wasn't a weasel....the Red Squirrel is a species I've never camera trapped before.  It's more of a northern species, preferring coniferous and mixed forests and isn't found in the more southern locale I currently live in.  It is one of five tree squirrels in the area.  The others being the Eastern Gray Squirrel (Sciurus carolinensis), the Fox Squirrel (Sciurus niger), the Northern Flying Squirrel (Glaucomys sabrinus) and the Southern Flying Squirrel (Glaucomys volans).

The Red is a cute little critter, coming in at only 11-14 inches long (including it's 4-6 inch tail) and weighing 7-10 oz..

Our second camera location (below) was selected based on evidence of past activity, and it's protected nature.  It was on an island we hiked out over the ice to reach.  A series of deer trails passed right through the middle of the island, which was covered by a small grove of evergreens and no understory vegetation.  It was obvious that critters used the spot as a little oasis when crossing the large area of open ice, where they were very exposed.  In past years, I had also seen weasel tracks on this island, and was again hoping for pictures of one of the little mustelids (which always seem to elude my cameras!).

So, we put down some more bait (minnows and some fish guts)...and I put a few drops of liquid smoke on the tree that the camera faced.

I've had good luck with liquid smoke in the past, and I hoped it would draw something in.

Above: having help in the field makes all the difference!  You can see Justin above helping me make my camera adjustments before securing it to the tree.

Unfortunately, open ice is also good for something else....snowmobiles.  On at least two nights I heard them zipping around on the ice and it sounded like they were very near the island.  Not much of a chance that any critters would venture out there on a night when the snow mobiles were cruising nearby. 

As a result, this camera produced nothing. 


The last camera was a road-side camera (below).  I had noticed the roads were the highest areas of wildlife activity during our past ice fishing trips (easier than pushing through the deep snow). This is a dirt road that is little traveled, since the cabin is on a peninsula.  So....hoping for wolf photos....I used alittle commercial wolf urine in front of this camera as an attractant.   I knew this might actually scare off anything else, but I REALLY wanted some wolf photos.

But...alas....no wolves showed themselves.

Apparently, however, fresh wolf urine isn't a big deterrent for Eastern Cottontails :)

And, thus, ended our 2012 ice fishing trip.  Although the camera traps were a disappointment, a great time was had by all and I can't wait to get back next year!