Saturday, May 11, 2013

Studying Amphibians in the Field: Using Approximate Measures

Red Eft, the immature form of the Spotted Newt. (c) Kim M. Bennett, 2013.


Frogs and Toads and Salamanders... Oh, My!

Here in Connecticut, we have just come out of the April showers that were not.

Oh, we had wonderful, almost summery temperatures, and the buds began to break. But, without any measurable rain in April, almost everything remained frozen in time, waiting. The spring peepers we wrote about in the last blog post grew a bit subdued in their calls, not having anywhere to lay their eggs. The peas and lettuces that we early gardeners planted begged for water to carry them through what is normally our rainy and wet time of year.

But we have rain this week! And, with that rain, spring is bursting forth rapidly! The amphibian friends that have grown rather hidden over the past few weeks are coming out in droves now.

Our frogs and toads broke onto the scene early this year, with a few brave spring peepers coming out during a warm snap in February, and our woodland frog and toad species making their debut last month (we haven't gone down to the pond to check out the more aquatic friends, yet... Stay tuned.) This month marked the first month we have seen salamanders.

Our Amphibian Survey: May 2013

Here is a photo gallery showing our survey of amphibians, to date:

Our amphibian survey, May 2013. (c) Kim Bennett, 2013.

We created this survey form so we can observe the changes in the seasonal distribution of the amphibians in our area, over time, as well as to chronicle the seasonal patterns in each specific species over the course of a year. We like having all of the information on one sheet, which is posted on the refrigerator.

Even the adult children take part (the photo of the red eft, above, is courtesy of #2 Son, the Animal Whisperer, who dashed over to our house early [I mean EARLY] one morning after finding the little fellow in his driveway as he left for work).

To get an idea of the relative number of frogs, toads and salamanders in our area, we decided to color code our entries so we could know, at a glance. Besides, at least two of us in the house (probably more) have a fascination with those 16-color Flair packs they sell in Staples.

Did I ever tell you I have a thing for office supplies? I think it goes along with being a teacher.

While there are three main groups of amphibians here on our chart, they actually are divided into the following groups, taxonomically [click on the name to see a photograph of a representative species - or the link, if we've already written about it]:

  • Mole salamanders (here is our post on the Spotted Salamander that the Plantsman rescued from the road one night after work)
  • Lungless salamanders
  • Mudpuppies
  • Newts (see the image at the top of this post, courtesy of the Animal Whisperer)
  • Toads (here is our last post, showing a photo of a Fowler's Toad that was strolling across the driveway)
  • Treefrogs (there's a great video showing Spring Peepers on our frog survey post)
  • Spadefoot Toads
  • True Frogs (here's a little Wood Frog that somehow ended up in our living room) 

Since tree frogs are arboreal, often the only way that you can observe them is to learn their call. When we identify a frog (or a bird, for our bird list -- especially our owls) by call, we mark the entry with a (c).

The Animal Whisperer found a Gray Tree Frog once and brought it to show us. We considered that a treat, since you are not likely to actually see them, most of the time. They were a lot bigger than I expected them to be -- not tiny like Spring Peepers.

It's always good to have a site that you can go to, to listen to calls of animals. Connecticut Amphibians has excellent photos, descriptions, and audio files to help folks in our state learn more about the amphibians here.  They also have a great discussion of the importance of vernal pools to our local amphibian species, something that is an important part of any amphibian study, no matter where you live. -- [Here is an image of a vernal pool in the nature preserve near our home] -- The Yale Peabody Museum of Natural History has a lot of great information, as well, but no audio files.

Measuring Amphibians

In our home, as well as in my classroom, we learn to handle wildlife gently, if at all, observe creatures for a short time and in a respectful way, then turn them loose. So we have to learn to observe them very carefully when we have them, so we can compare later. Having a digital camera is a wonderful asset to both homeschool and classroom, when it comes to reflecting on and studying things that we can't really hang onto for a long time.

If you are going to use digital images as a way to observe animals, try to make sure that you snap them with something in the frame that shows scale. See the images, below, for ideas:

This photo from  "Frog-Hunting in Connecticut" shows a Fowler's Toad in the parking lot. I waited until it hopped closer to the parking space number (most of us can visualize how big those numbers are -- about a foot tall) so you could get an idea of how very large the toad actually was -- about 6 inches long, although adult Fowler's Toads can be up to a humongous 9.5 inches long! Wow!

I considered getting a ruler to place alongside the toad, but my dog was so excited about the toad that I was afraid 1) the toad would be startled and hop away or 2) the dog would try to eat it.

Here's a great way to get a pretty accurate measurement of your amphibian, if it's one that slows down enough for you to gently pick it up.

The fingertip joint of an adult's first finger is about an inch long. Actually, this joint, even in a child from about the age of 8, on, is about an inch long. I used to teach my third graders to use their first finger joint as an approximate measure, if they didn't have a ruler. In this photo, you can use this measure to estimate that this little eft (which is probably on the large side, for efts) is about 3 1/2 inches long, from nose to tail tip. Red efts range from 1 1/2 to 3 1/2 inches long.

Here's that photo of the Spotted Salamander from "A Night-time Surprise: Spotted Salamanders", showing another visual cue you can use to estimate the size of one of your amphibian friends.

My son was carrying the salamander from one side of the road to the other, in the front of his tee-shirt. In the photo, you can see the hem of his shirt. If you are wearing a tee-shirt now, check out the hem at the bottom. If it's a regular shirt, the folded over and stitched part will be about an inch wide. Accounting for the semi-curled up nature of the little fellow, we can estimate its size to be about 8-9 inches long, from nose to tail-tip, so it's probably an older member of its species, which range from 5 inches to 10 inches long, depending on their age. They can live up to 10 years, if they don't get run over during breeding season.

Data Sheets and Notebooking Pages, for Your Amphibian Studies

In the last post, I shared a link to "Animal and Plant Surveys: 10 Reasons to Get Outside and Survey," which explained the science behind surveys as a learning task. I also included links to blank survey sheets, such as the one I showed, above, which you can use to keep track of your animal species.

An amphibian study is a great opportunity to compare animal species, too. For one way to study comparison using an interactive bulletin board, see "Comparing Nests: The 'Same and Different' Center."

There are many sources of Venn diagrams (all kinds of varieties). At  {.docstoc}, you have many to choose from, all downloadable, free of charge.

We download a lot of our general nature study pages from The Notebooking Treasury - we have been members since we began homeschooling in 2010. From now through May 31st, 2013, they are having their 7th Birthday Sale-a-Bration Event, with discounted merchandise, chances to win prizes, and specially priced memberships (for new members) and membership extensions (for current members).

Become a Notebooking Pages LIFETIME Member (as we are) during their 7th Birthday Sale-a-Bration Event, and you get all this:
  • Save $25 on your membership
  • Receive access to 150+ current notebooking products
  • Receive ALL future notebooking products
  • Receive up to two years FREE access to their notebooking (& copywork) web-app, The Notebooking Publisher™
  • Receive a $100 e-gift Bonus Bundle from various homeschool publishers
  • Earn a chance to win some great prizes … an iPad mini, $100 gift card, LIFETIME access to The Notebooking Publisher™, and a LIFETIME membership to

How could you resist?

Try Our Amphibian Study Pages - FREE!

During the next four weeks, you can enter to win a copy of My Amphibian Survey, a 36-page e-Book full of notebooking pages, centers ideas and curriculum extensions on amphibians. Two lucky contestants will get copies of this e-Book. Also, in honor of springtime, we are raffling off one copy of Nests, Nests, Nests! - our fall e-Book on nests of all kinds of animals (including amphibians) for one lucky contestant. Just enter using the Rafflecopter Form, below.

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