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Exploring a Vernal Pool

By Arianna & Frank Grindrod

Yellow Spotted Salamander 1

Yellow Spotted Salamander

Spring is in the air; in the yellow spotted salamander’s feet marching across the snow; in the trill of the Spring Peeper announcing his space and his availability as a mate; and the quiet patience of the Fairy Shrimp waiting between the mud and ice for their home to thaw.

What Is a Vernal Pool?

A vernal pool is a small woodland wetland that is created by melting snow in an earthen depression which has no inlet or outlet; basically a “wicked big puddle”. These “puddles” are nurseries for several species including mole salamanders such as the yellow-spotted salamander, wood frogs, spring peepers, fairy shrimp, and fingernail clams. Vernal pools are usually temporary and dry up as the season progresses. For the animals who them as a nursery, it is essentially a race against time for the babies to grow up enough to be out the pool before the water is gone. Some pools are semi-permanent but that is not a guarantee so ether way, the salamanders and frogs are crawling or hopping away come summer. The invertebrates, those who cannot fly or crawl away, but are obligate to the pools such as the fingernail clams and fairy shrimp must squiggle down into the mud and wait until next spring to emerge again.

Who Might you Meet at a Vernal Pool?

Mole salamanders live underground which is why you don’t tend to see them any other time of year…except for the Marbled Salamander who lays her eggs in the fall in autumnal/vernal pools. She hoovers over her eggs until the rains fall and then she leaves them. These little ones are the first to hatch and will eat other species of mole salamander eggs in the spring when the pool has then been filled with Jefferson, Yellow-Spotted and Blue-Spotted Salamander eggs. All mole salamander species eat invertebrates and will use mole-excavated tunnels, hence why they are called mole salamanders. In the Spring, when the first rains tickle the ground and when above ground temperature reach 40 degrees Fahrenheit, the Yellow-Spotted, Blue-Spotted, and Jefferson all come on down to their home pools. The males arrive first, forming what is called “congress”, a group of salamanders. They may travel up to a half mile away from their upland forest underground homes to mate in these vernal pools. After they mate they return to their woodland homes. Watch for them on rainy spring evenings as they cross the road.

Spring Peeper in driveway

Spring Peeper

If you live near a vernal pool you may hear a din of sound that is caused by two vernal pool visitors – the Wood Frog and the Spring Peeper. The Wood Frog is one of our black-masked bandits (can you guess the other two? One is a mammal and the other is bird.); a woodland, territorial amphibian that has a very distinctive call – the singing males, who are calling out to alert everyone in the vicinity that this is their space make a “qua-ack” sound, vaguely reminiscent of duck. The Spring Peeper is a very tiny tree frog who bears an “X” on his/her back. The callings males make a high-pitched “ree-deep” sound.

Vernal Pool Fairy Shrimp

Fairy Shrimp

There are a host of invertebrates that you can find in a vernal pool – from Predaceous Diving Beetles and Whirligig Beetles to Damselflies to Backswimmers and Water Boatmen to Mayflies to Amphipods, Isopods, Daphnia and Copepods to Fairy Shrimp to Fingernail Clams to Caddisfly larvae. These are species worth getting down and dirty with as each sport their own unique adaptations of locomotion, feeding and general survival. For example, Whirligigs have split eyes so they can see up and down at the same time; handy when watching for predators. Mayflies have fanlike gills on their abdomen to take in oxygen from the water. Predaceous Diving Beetles have their own scuba gear so to speak; they carry an air bubble at the base of their abdomen as they swim through the water. Caddisfly larvae make their mobile homes from debris they find in the pool and their silk. They have a little hook on the end of their abdomen so they really do hitch up to their home and crawl along the bottom of the pool. They keeps their soft bodies protected and camouflaged.

Exploring a Vernal Pool

Vernal Pool 2 2004You and your youngster can gently explore these nurseries using a simple dip net and a holding pan. Fill the pan with water from the pool being careful to obtain the clearest water so that your temporary holding container is not muddy. Now gently slide your net through the pool and along the edges to catch a critter. Gently put it in the pan using a plastic spoon. If you have a magnifying lens and an identification guide book so much the better. Watch how the creature moves. It is recommended not to place predators and prey species in the same holding container at the same time else you will be setting the stage for the prey to be on the losing side of the chase. Please also do NOT collect eggs as this action may destroy the embryos.

When you are through studying these amazing creatures please return them to their home in the pool. To emphasize to your young naturalist the importance of respecting wildlife you can end with a simple “repeat-after-me” releasing ceremony such as this one that I (Arianna) learned from Kim Noyes at Northfield Mountain Environmental and Recreation Center many years ago.

“Run away, crawl away, swim away, hop! You are free to go. I am not going to stop you from living your life. You deserve to be free; but thank you for spending this time with me.”

Suggested Field Guide: A Guide to the Animals of Vernal Pools by Leo Kenny & Matthew Burne.

Amphibian Etiquette
Amphibians, including frogs, toads and salamanders, breathe through their skin. Their skin is very sensitive to many things (salt, chemical toxins, soap, bug repellant, chlorine in our drinking water, sunscreen, etc.) When handling our wild friends, please remember to create a micro-habitat between you and them. Create this layer by putting your hands in their water source (vernal pool, pond, bog, stream, etc.) if they are aquatic or by using soil and leaves if they are terrestrial. When holding an amphibian make sure you keep them low to the ground and be mindful that the temperature of your hands can raise theirs, and this can create stress for them. Always return them where you found them. Or, if you are helping them cross a road, always remember their direction of travel and place them on the proper side of the road according to their direction of travel.

Seeing WILD Life…Who Is Watching Whom?

WildernessWinter has come and gone, and spring is clearly unfolding: the birdsong, the wildflowers, the bursting of shoots braking through the Earth’s surface in fertile ground, the trees leafing out, the warmer days as frogs sing, and then in the spring, showers are coming as the ice melts off the mountains, bringing it down through the rivers. It’s a powerful time of change.

My daughter and I–with binoculars in hand and our favorite walking stick, backpack filled with food, water and a couple of field guides, map and first aid kit–venture into the forest, as the sun rises, with a goal of seeing wildlife and not being seen. We move quietly through the deep forest, moving like a ghost, invisible as best we can while using the Indian sign language we have been practicing.

We are so blessed to be in the middle of a magical place with such a rich diversity as we are in southern New England…a world where the boreal forest and the northern forest meet, giving us the best place to be immersed in nature. The boreal forest, also known as “the spruce-moose forest,” has mainly evergreen trees and a few select hardwoods like poplar, paper birch, tamarack and others. The northern hardwoods have such a vast amount of trees like yellow birch, sugar maple, American beech, eastern hemlock, white pine, northern red oak, cherry, and those are just a few—there are many more.

As we trek deeper into the forest, we notice the dense canopy not letting in much sunlight as the sun rises out of the east, giving us a sense of direction, but our awareness tunes into a subtle change, and as we enter, there is more light shining down on us than just a minute earlier. This is a track on a large scale that is affecting how much light which helps to make a more rich forest in vegetation and brings with it many animals and birds and the like. With our senses honed, there are signs of the animals all around us. We notice claw marks and bites on trees, stunted growth where it looks like a nursery of Japanese bonsai trees, and when we look down in the leaf litter, there are many footfalls showing worn-in paths on the forest floor, weaving in and out of the cliffs.

Passing through different habitats, we see the many deciduous leaves and all the light that shines creates a dappled look under our feet and in the area between the wetland and the cliffs. There is a lot of feeding sign called browse (little 45-degree angle cuts), taking the end of the branch clean off, almost like clippers.

Place to hide?As we expand our awareness to the area high up on the cliff, we see a good hiding place opposite of the spot we want to watch. Scanning for signs of movement, we hope to get a glance of this very elusive animal who chooses the south-facing, hard-to-access areas in the cliffs. We have already done our research; we know this animal is crepuscular, which means it is active at twilight hours (dawn and dusk). It is diurnal (day) and nocturnal (night).

Another place?Its primary food source has left sign with the angled cut that we found earlier, so we know there is a feeding area in close view. One of the traits of this animal is the ability to be motionless for long periods; even in winter, being able to lay in the snow where you can find a sphinx-like “hunting bed” while it waits to ambush its prey. To discover this body print melted out from the heat that is generated while it remains still as a shadow is inspiring! As we get down low, we find sections of hair frozen to the ice; however this time of year, you want to look for “resting beds;” places where you can make out where it has been laying down, usually under a rock overhang on a pile of leaves insulating from the ground.

resting placeThe forest is so quiet. My daughter and I take turns to scan the cliffs with our glasses. We have been watching, quietly, for almost an hour and a half. We know that patience always pays off. We also know that this animal has a very small heart and it travels a very short range compared to others of its size. By knowing this, we also could watch it hunt as it stalks its prey since it is primarily a carnivore.

While looking near the top where we have been looking all morning, in the best rays of light, we see movement–a very camouflaged tawny color with dark shades and beautiful markings, big eyes and graceful movement as we watch it stretch basking in the suns glow. It has been there all this time…watching us watching for her. So who’s watching whom? While studying us, perhaps, she senses we are not a threat.

It is time to hunt. Her preferred prey, the rabbit, helps to sustain her but also helps raising her kittens. If you haven’t guessed by now, the mystery animal is the bobcat.

bobcat babyAs we watch our cat in her natural rhythm, we are excited because we may be able to watch her hunt. Earlier we mentioned how she lies in wait in “hunting beds.” Once the prey is close enough, there is an explosion of energy–a POUNCE! From her ambush spot, bursting forth after the rabbit who has zigzagging motion to avoid capture. There is a very small window of time because she needs to not burn too much energy; if the hunt lasts longer than just minutes, she will stop rest, find another spot and start again and continue that cycle.

This bobcat needs to eat and feed her new kittens, and when she has the rabbit, she will take it to a place close by to hide it and take parts of the animal and “cache” (cover and save for later) the rest, using her front paws very much the same as our house cats. She will travel back and forth to feed her young if she has gotten a good amount of food. She will continue to hunt this area because of the success.

Thanks for joining us on our adventure into the outdoors.

Until next time happy trails…

An Introduction to Tracking: Seeing through the Eyes of the Forest

Welcome Winter!

There are always amazing things happening in the outdoors, and all of them leave stories. This is an amazing way to learn: it puts the QUEST back into question and the SEARCH back into research. It also helps to engage all the senses: touching the tracks, listening to the birds, and letting the listeners know if the animal is still around them.

“Let’s follow an animal. We see some footprints in snow.” We all gather around, making sure not to step on the tracks; this is harder than it sounds with the excitement of everyone. Then we get close and reach out with our eyes like we are mountain climbing and we have shrunk ourselves down to climb in the track. We see that it looks pretty deep.

We start to measure and discover it is about an inch. Then Chris says, “I think it is a wolf!” We ask why? “I picture a wolf walking. We are reading a story about a wolf at home, and I would love to see one…” This is a gift; their imaginations are brimming, the tracks are coming alive, and the excitement builds!

Who’s got their journal? “Oh I do; it’s right here,” say several of the kids. They whip out their backpacks and start to make a sketch right there on the spot. Now the one measuring is working with the ones who are sketching.

There have been no answers given yet. We are in the brainstorming stage of tracking where everybody is sharing their direct observations, thoughts and feelings. There is a real magic at this point; an energy that flows throughout the group.

I ask some questions: “How many toes are there? Any claw marks?” There is a silence while everyone begins to get closer to the tracks. “I think this is a toe and this is another.” We all agree there are two huge toes that are about 3.5 inches long, and the width is 2.5 inches. I ask, “What shape is the overall track? A circle? Square? What do you see?” One of the girls says, “I see a heart.” “Me too!” agrees Maya. “Oh yeah, it is a heart,” confirms another.

I fuel their passion by reflecting back to them–“You are becoming great trackers.” “Now does anyone see the line right down the middle of it?” Someone exclaims “I see it! It is down by the bottom of the heart of the track.” I suggest an idea: “Why doesn’t everybody point which direction the animal is moving…on 3; ready…1…2…3!” Most of the students point where the mystery animal is headed. “Awesome! Way to trust your intuition!” I praise.

“Let’s look deeper. Did anyone bring any tracking guides?” A couple kids bring them out as I do. We all huddle around the guides looking for the tracks. It is now a matching game. “Are these fox tracks?” “No,” the group answers together. “These are way too big.” I ask one of them to make a track right next to our mystery track. He starts, and everybody watches. “Try to make it as deep as that one and feel how much weight–a lot or a little–it takes.” “Whoa! I am putting all my weight down, and it is just barely the same.” I ask, “Is this a light or heavy animal?” A resounding “heavy!!” is the reply.

Sometimes it is more important to have more questions than answers, like assigning a name. A lot of times I have noticed when I just share an answer of what I know, then the curiosity and mystery ends, and sometimes the experience as well as the discovery part of the need to know stops. I hope you can watch for it next time you are sharing or teaching.

Back to woods!

The kids start to guess certain animals and are showing and asking each other “do you think this is it? what about that?” This is a great example of how peers teach peers; they are mentoring each other!

Maya Tracking winter

We researched coyote, fox, otter and deer. There is a reason that I have them go through their guides; this is called coyote teaching–deepening the experience for them so they know what they know and they are learning how to learn when we, as a parent or teacher, are not there.

About the field guides: these guides are respected and revered as modern day elders with extreme knowledge and life experience. They have thousands of field hours in them. Lots of times there are also personal stories in them along with facts of behavior and measurements, etc.

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