Thursday, September 27, 2012

Field Ecology Methods Week 2 (2012): Reptiles

After a week of invertebrates and Limnological techniques, the students spent some time learning how to conduct some standard surveys for reptiles.

First, we checked the existing artificial cover objects on-site for snakes....

This resulted in only TWO juvenile Gartersnakes (likely born this year).  But it was unseasonably warm on the day we checked the boards (upper 80's)....probably too warm for snakes.

The students then worked to measure out additions to our existing coverboard grid. 

Few things make me happier than to see all 18 of these students working hard in the field and no one standing idle.

Let's face it....field work can be grueling (especially in the warm conditions we had while deploying the boards).  But, this gives the students a small taste of less than ideal field conditions that one might face as a field ecologist.  It's not all catching Cougars and Narwhals every second (or as a colleague here says...there's not a "gorilla behind every tree").

After the artificial cover objects were laid, we moved over to the creek and deployed some hoop traps for turtles.


The traps sat for a night, and a small group of volunteers came out with me the next morning to check and re-bait the traps.

Thankfully, we had more luck with turtles than with snakes.

Two large adult Snapping Turtles (Chelydra serpentina).....

Five cute little Painted Turtles (Chrysemys picta).......

We took our morphological measurments, such as carapace (or upper shell) length....

Then we released the turtles back into the stream.

The next day it was back to check the traps again, and this time the entire class was present.

...and once again, we had good fortune!

Day 2 yielded 14 painted turtles and one little snapper....a good haul!
Once again, appropriate morphological measurments were made....the turtles were given a permanent mark....and released back into the creek. 

Hopefully, we'll see some of them again in the spring!

For more information on standard survey techniques for reptiles, see this excellent new book:

McDiarmid, R.W., et al. 2012 Reptile Biodiversity: standard methods for inventory and monitoring. University of California Press. Berkeley.

The following book is also a good introduction to standard reptile survey methods.  Unfortunately, it's out-of-print, but you can still get it from libraries or through interlibrary loan.

Karns, D.R. 1986. Field Herpetology: methods for the study of amphibians and reptiles in Minnesota. Occassional Paper 18 of the James Ford Bell Museum of Natural History, University of Minnesota.

Sunday, September 23, 2012


Keeping with my sibling rivalries string of posts, here are the best close-ups of raccoons getting after eachother that I have gotten to-date....

Pretty humorous to watch, as well!

Everything appears to be going swimmingly between these two, when suddenly one bolts.....and that triggers it.

Then it's on!

The two chase eachother out of frame at some point.

Then about three minutes later an individual I call "Stumpy" randomly meanders through (apparently minding his own business).

Stumpy remains in the background and doesn't seem to know what he's in for....

......until one of the pugilists returns. 

Cautiously the contender scans the top of the reed canary grass looking for his antagonist.....but still gets blind-sided!

The two square-off and Stumpy quickly decides he's had enough and skee-daddles!

A VERY brief respite before getting back to the action....

Which then continues....

....and continues....


But, something suddenly catches their attention....

...and then they're gone......

Monday, September 17, 2012

Phenology: Buck Past Velvet

I recently obtained the first evidence of a White-tailed Deer buck without velvet in 2012.

These clips were taken on Sept. 8, 2012.

September is the primary month in which buck White-tailed Deer rub the velvet from their antlers in preparation for the rut (although there is variation in this date, and velvet may be rubbed off as early as late August, or as late as November).  The triggers for this rubbing behavior are the result of a battery of hormones, but changes in testoterone levels (often triggered by changes in daylength) are important.  For example, according to Miller et al. (2003) the "hardening of the antler and shedding of velvet are a direct result of rising testosterone levels cued by shortening daylength."

Compare this to the first hint of antlers since this year, way back in April.....

Literature Cited:

Miller, K.V., L.I. Muller, S. Demarais. 2003. White-tailed Deer (Odocoileus virginianus). In Feldhamer, et al. Wild Mammals of North America: biology, management, and conservation (second edition). Johns Hopkins University Press.

Thursday, September 13, 2012

Field Ecology Methods Week 1 (2012): invertebrates and limnology

We have a 200-level field methods in ecology class that is required of biology majors in our field ecology concentration.  It's meant to expose students to a variety of different field techniques, to give them a general flavor for what's out there (and...frankly...allow them the opportunity to learn if they don't like field ecology before they are a senior and can't switch their concentration!).

I helped out with our summer version of this course a few months ago (see here).

It's team-taught and each faculty member brings something different to the table, which is great.

I'm coordinating the course this semester.

We started off the course last week with some field survey techniques for insects, taught by our resident entomologist.

First, the students were given a bit of instruction on the tools they'd be trying....

Then it was off to do a bit of collecting....

Some students started by knocking insects from dead tree branches into the apparatus below.....

Others tried their hands at catching flying insects with the hand-held nets.....

After insects were captured with the methods involved, students took some time to experience grabbing them with a special tool called an "aspirator" (see below).  Basically, this device allows one to suck up an insect into a sample bottle, without fear of accidentally swallowing it.  The aspirator also allows students to catch insects without having to grab things that might sting or bite their fingers!

I joked with the students that I wanted as many pictures of them using these "aspirators" as possible, as there is no way NOT to look dopey while using them :)

But hey...they work!  And by the end of the lab, they had caught some stuff.  I missed pics of some of the cool spiders they found unfortunately.  Too caught up in the moment, I guess).

Soldier Beetles (Family Cantharidae), juvenile Boxelder Bugs (Boisea trivittata), and a Katydid (Family Tettigoniidae) below....

Lab 2 last week was focused on a simple introduction to standard Limnological techniques.

Again...we always start off with a bit of instruction...this time from our resident Limnologist/Aquatic Toxicologist....shown here holding a plankton tow net.

Then, it's down to the dock to take the equipment for a test-spin and collected samples to be sifted through back in the lab at a later date.

This included (in addition to the zooplankton net), some hands-on time with the Secchi Disk, which is a standard tool for measuring water clarity.

Students also experienced using an electronic water quality meter refered to as a Quanta Multimeter (made by Hydrolab).  It measures dissolved oxygen, pH, water conductivity, temperature, depth and turbidity (or clarity).

Students used Kemmerer sampler (below) to sample phytoplankton which may be too small for the mesh size on the zooplankton tow net (since zooplankton are larger than phytoplankton).

...and then the rain began.....

...and then it REALLY started coming down.....

But I heard not one word of complaint.

And, as an instructor, that always pleases me when things don't go as planned...

Saturday, September 8, 2012

What Spooked the White-tails?

Deer tend to mill about in front of my cameras with some complacency.  I typically get video clip after video clip of them wandering in circles and grazing (especially the fawns).

So when I saw this clip, it surprised me a tad.  This fawn is clearly on the alert....head up, looking around, ears swivelling, nose working.

I was even more surprised to see her and momma suddently bolt in a subsequent clip....

Why did they bolt?

About two minutes later, the reason(s) trotted into view. 

But when something just doesn't feel right....even these two are gone in a heartbeat.