Saturday, April 28, 2012

Advanced Ecology Lab Week 12: Annual Field Trip

The morning broke cold, wet, and gray.....

Normally.......not a big deal.....

HOWEVER, because today was the date I had selected back in December 2011 for the first annual Advanced Ecology Lab Herptile Field Trip......"cold", "wet", and/or "gray" were things I had fretted about for this trip since January. 

It's been beautiful for much of the spring here.  We also had beautiful weather yesterday....and are supposed to have beautiful weather for the days to come.  So why the weather picked TODAY to be cold and rainy is beyond me!

But, the vans were reserved, the date was picked months ago, and there was no turning back at this point. 

So we had to make the best of it.

And we did!

Anyone who read this blog last summer knows that I'm cold-blooded at heart, and I love herptiles....particularly snakes.  So, I had planned this trip to coincide with what is (usually) a good time of the year to see snakes at some sites I spent alot of time on during my dissertation.  So I came up with a trip centered around the opposite side of the state from where we are located.  Over there, the landscape (topography and major habitats) have had a different geologic past than the rest of the state.  Lots of topographic releif.....much more xeric conditions....lots of sand.  The entire area is either in a current (or ancient, in some cases) river floodplain.  In our state's geologic past, an ancient glacial lake drained through the area as a large river that meandered back and forth across the plain, depositing this sand throughout the region as it went.  As a result there are exposed rock cliffs (eroded down by the river many, many years ago), and lots of sandy prairie in the old river bed. 

This unique pre-history means there are a much different host of plant species found there compared to where the university I work at is located.  Furthermore, the reptile species found there are different than where we live several hours away.

We were also fortunate enough to have a good friend of mine come along with us on the trip.  He worked many years for our state regulatory agency, in the endangered resources division as the cold-blooded specialist.  So under his purview were amphibians, reptiles, non-game fish, and invertebrates that were protected in the state.  He gave the students some nice background information on the history of the sites, the difficulties associated with managment of the habitat (and species therein), as well as discuss the difficult situations that arise when mitigating problems that occur when humans and wildlife don't have the same agendas!  A good thing for any up and coming wildlife biologists to note....and as my friend said today repeatedly....wildlife management, regulation and protection often involves a significant amount of human management.  It involves learning to deal with personalities, learning to resolve conflict, and working to educate folks who don't care about, or don't like wildlife (and often blame state regulatory agencies for their troubles).

The first site we visited was a large river floodplain forest.  Great for amphibians under warmer conditions.  But also a good place to learn some history about the habitat managment that has occurred on-site, and for the students to hear about the nitty-gritty of what types of considerations are neccessary when managing habitat and/or species.

Of course, despite the cold, it wouldn't be right if we didn't spend some time in the woods rolling logs for amphibians.

 Some of us were more ambitious than others, when it came to selecting good logs to roll.....

...but the result was some cool critters captured.....including the wood frog (Rana=Lithobates sylvatica).  Easily recognized by it's tan/bronze/brown color and dark mask....  The wood frog is one of the earlier species to call in the state, and also has possibly the shortest breeding season.

It came to my attention that some folks in the group were uncomfortable with holding these harmless little critters.  Being the overly-sensitive soul that I am, I then demanded they open their palms and hold the frog. 

This took alittle coaxing.......
 ....but in the end, everything turned out fine....

In fact, the other critter we came across (the blue-spotted salamander, Ambystoma laterale) was handled with slightly less trepidation....

Our guest for the day also brought some examples of other amphibians for the students to get alook at.  These included, a nice larval tiger salamander (Ambystoma tigrinum)....

....some central Newts (Notopthalmus viridescens) in their adult aquatic phase....

....and a nice adult spotted salamander (Ambystoma maculatum)....

Then it was off to the sand prairie!

This was a site I was really hoping would produce snakes, but was doubtful given the cold.  There are several snakes that are protected by the state on-site...and one turtle (the ornate box turtle, Terrapene ornata) that is listed as endangered.

Unfortunately, this site has been hit hard in decades past by "herp enthusiasts" and collectors....who in the 70s and 80s cleaned house on the populations of these rare reptiles, setting their populations back severely.  Surprisingly, collecting on-site can still be a problem (why folks want to keep these critters as pets rather than just enjoy them in the outdoors, is beyond me...but whatever).  So we tried to really make this point hit-home with the students.  The site is special, and so are the species that live there!

With the very bizarre weather we've had this spring (hot early on, and now relatively cool) I didn't know how the spring flowers on the prairie would react.  Luckily, many of my favorites were still in bloom when we arrived.

Including, the Birdfoot Violet (Viola predata).....

...and the Priarie Smoke (Geum triflorum) named because when these red buds open the seed heads are fluffy and wispy, almost like a puff of smoke.

We also saw some interesting warm-blooded wildlife sign.

First was a deer carcass....

There was clearly evidence that something had been at the carcass feeding and had dragged it to this location.  We also found the likely culprit's residence nearby. 

I asked the student to stick his head inside the entrance to this coyote (Canis latrans) den for scale.  I was pleased to see he was smart enough to mostly decline. :)
...a secondary entrance just down the ways on the same earth/sand berm....
Can't say for certain that the 'yotes had actually killed this deer.  There was good evidence that it was a carcass that had been dumped nearby by a hunter...and the 'yotes had just drug it closer to the den for easy pickings.

Below is a mound created by the sub-terranean activities of the pocket gopher (Geomys bursarius).

There were also grassland bird species on nests already.  Once they flush, it's relatively easy to find the nest.  A Mourning Dove nest below....

More exciting was a Meadowlark nest (see below).  It's hard to know if this is the western or eastern Meadowlark, as both are on-site.  The eastern has always been one of my favs....they used to call along the fields near my grandmother's house as a kid.  I do get a chuckle out of the Western Meadowlark's scientific name: Sturnella neglecta.  Perhaps it was viewed as the neglected Meadowlark compared to the Eastern (Sturnella magna)? 

But....luckily..the reptiles did not completely evade us!  One of the students came up with this real gem....the state's rarest turtle: the Ornate Box Turtle.

This little one was a juvenile.  He looked and felt cold (I don't think it broke 50 deg. F today!). 

It was also special in that it was a "head-started" individual.  The head-starting program is a management strategy implemented in an effort to augment the populations of this incredibly rare turtle throughout the state.  It involves collecing eggs from the wild, incubating them in captivity (to save them from the voracious mesopredators, such as Raccoons and Skunk that have a hey-day eating turtle eggs during the nesting season).  The turtles are hatched in captivity and then released the following spring, when they are substantially larger and their shells have hardened (making them less vulnerable to predation).

This program has been running for over a decade in the state, and it's encouraging to randomly find head-started juveniles from years past.....which suggests the program may be paying off!

We finished off with a visit to a site that is normally great for Northern Watersnakes (Nerodia sipedon), but of course none were active today.  Yet, it's another interesting habitat....and open water marsh backwater of a large river in the state (compared to the river floodplain forest we visited during the morning).  It also has a very interesting management history (which, when first began, mostly focused on waterfowl).

....but ultimately made for a nice group photo-op....

We had a fun day.

Next year, maybe we'll have better luck with the snakes!

Sunday, April 22, 2012

Phenology: antlers, toads and treefrogs....

It seems like some of these bucks just lost their antlers!  There were individuals showing up on our cameras in February that were still holding their racks....and already they've started to come back in some males.

No doubt it's a high-resource environment, with an associated risk of mortality that must be pretty small.....  Also, I guess the testosterone has started flowing again!

This is not too far off from when I first started seeing the antler buds peek through on the bucks when living down in NC last year....


On the evening of 4/15/2012, I heard the first American Toads (Bufo=Anaxyrus americanus) calling of the season.  These were pretty early like many of the other frogs this year....but not as far out of their normal time as the Chorus frogs (Pseudacris triseriata) have been.  They did not call for very long (one or two strong nights) and then the weather cooled, which seems to have slowed them.  I imagine I'll hear them again.....

It's also worth noting that I am also still hearing Chorus frogs calling with some intensity....despite the fact that they began so early this year.


Although I have not heard Gray Treefrogs (Hyla versicolor) calling yet this year (that would be WAY, WAY early)....I saw my first adult of the year.  Just behind he house on our deck.  We have been preparing some of our potted flowers and vegetables for the coming summer and I moved our potted blueberries out of the garage and onto the porch today.  There was a pile a leaves near the vent for our clothes dryer that was about where I wanted to put the blueberry pots.  I was brushing these leaves out of the way by hand, when out tumbled a nice little treefrog.  The leaves were damp and the dryer vent must have provided alittle warmth as we were doing laundary. 

Much to my daughter's delight, we got to look closely at him as we moved the blueberry pots into place.  I left some of the leaves in a pile near where I had moved them from (so they were next to the blueberry pots).  Then I carefully placed the little fella in one of the pots, figuring he could move on his way as he saw fit.

I wonder if this was one of our nocturnal hunters from last summer?

Thursday, April 19, 2012

Advanced Ecology Lab Week 11: The Rodent Box

This week had the students continuing their assessments of the diversity on-site.

They did this by conducting small mammals surveys (basically rodent surveys) with baited live-traps called Sherman Traps, which we placed in both woodland and field/meadow habitats on-site.  Anyone who has ever done field work on rodents knows what a Sherman Trap is.  It's the standard in live traps for these kind of critters, and the basic Sherman trap is a metal box with a trip plate inside that allows a door on a coil to snap shut once the animal is inside.  They are baited with peanut butter and oats...perhaps some seeds for added attraction.

But invisible grid needs to be measured and flagged so that the traps can be deployed in a systematic fashion (actually traps can also be deployed along simple straight-line transects and randomly).  Deploying them in precisely measured grids allows for trapping area and level of effort to be kept constant if one wants to sample across multiple habitats (or even study sites).  

So, off they went to measure their grids.....

A simple 25 trap grid can be (for example) 40 meters X 40 meters (traps placed at 10 m intervals).  This requires a bit of precision to keep the grid square.  It's best to start by finding a direct North-South line with a compass...then laying a tape measure along that exact bearing, to keep the line straight.

 Once that is complete, laying traps (or putting in flags) every 10 m gives you one side of the grid.  From that original starting point, it's neccessary to then determine an exact west-east bearing....lay a tape measure out, and finally mark off 10 m intervals with flags or traps.

The result might be something like the diagram below:

This part is relatively easy when you're in a wide-open a meadow.  But it gets a bit more difficult when working in woodlands. 

Next comes the real tricky part: laying out the rest of the grid.  It's usually easiest to begin in the lower right corner of your grid...and then to start measuring out 10 m X 10 m cells.  To make sure these are correct, one must also measure the diagonal distance across the cell....and when that is correct, you can place your next trap.  See figure below for an example of how to start the grid:

Measuring each cell in your grid is easy when there are no obstacles.  In fact, the students working in the grassland were done in no time.

Above: holding two 10 m tapes to find the new grid intersection.  Note the yellow tape measure that will be used to measure the 14.14 M across the diagonal to make the cell square.

After the traps are baited and set, it's a good idea to get a GPS reading of your grid corners (or one of the corners) to find the traps more easily.  Note the flag and the Sherman Trap at the foot of the student with the GPS unit.

The next morning, bright and early, the traps have to get checked and the captured critters released (which is the fun part). 

Although we didn't catch a ton (that's what happens with only one night of trapping!), we did catch a few White-Footed Mice (Peromyscus leucopus)....and I can't help but think they're cute little buggers.

We'll do another round of trapping next week.  I'm hoping for some Microtus...and even a Tamias would be fun to wrangle!

Thursday, April 5, 2012

Advanced Ecology Lab Week 10: Spring Break Edition!! (...or....the Tod on the hunt).

Well, the students were all gone last week for Spring Break.  They went off to enjoy warm places, I suppose.  I, on the other hand, was able to view spring break as a time to actually get caught up on work (how different life becomes when you're a responsible adult :)  ).

I did take some time to get out to the field sites we're assessing for class, and check on all of our cameras and long-term experiments, so they didn't go without attention for two weeks.

The cameras had been busily snapping photos. 
(however, I should warn anyone who clicked on this post hoping for well-bronzed skin, swimming trunks and're likely to be disappointed)

Deer, Raccoon, Eastern Cottontail, Eastern Gray Squirrel all generated many photos.

But the week, again, belonged to The Tod.

Once more, we caught pictures of him/her on nearly all of our cameras.....

We also got a great series of pics of him/her hunting the grass for something (a rodent, I'm assuming).

The critter can first be seen in the back ground (look for the eyes in the grass)....searching for something that draws him progressively closer to the cam.

....that wonderful tail......

The 10 second interval between triggers brings him right up into view......

Always have eyes in the back of your head!

....but also try not to get distracted from the task at-hand!


The semester is rapidly drawing to a close!  But there is still more to come before we pull the cameras and shut this project down for the semester.....