Vernal Pools of WrenthamVernal Pools of Wrentham

Slide Show and Photos by Mr. David PickeringSlide Show and Photos by Mr. David Pickering

“There are hundreds of vernal pools in Wrentham

on public as well as private land.”

Fifth grade students have certified over 15 vernal pools in Wrentham

A sampling of vernal pools that have been certified in

Wrentham

Wrentham State Forest Pool

Madison Street Pool

Pig Pond Pool in back of Roderick

Another pool in the Wrentham State Forest

Birchwood Farm Pool

Pool in back of Lake Pearl Boat Landing

Private Pool at Sleepy Hollow

Pool in back of Franklin St. Pumping Station

Pool in Crocker Pond Conservation Area

Another pool in the Crocker Pond Conservation Area

Another Pool in the Wrentham State Forest

What is a vernal pool?

• Temporary pools that fill with water in spring

• Usually go dry in the summer

• Necessary for breeding by obligate species

• No fish• No running water

Vernal pools remain dry from summer into late fall….

Dry Trout Pond vernal pool (Sept.)

Same Trout Pond vernal pool filled with water in April

Importance of Vernal Pools

• Some species are completely dependent on vernal pools for parts of their life cycles

• Obligate, or direct indicator species, must have a vernal pool to breed

• Facultative species use vernal pools for various life activities

• Various other mammals, birds, insects, and amphibians also use vernal pools to drink water and for other life activities

• Important for biodiversity

The Big Night

• The one night of the year, usually in March or early April, in which obligate species go in masses to the vernal pool to breed

• Usually a warm and rainy night

• In some places roads are closed to allow safe passage

Obligate Species

These are species that are completely dependent on vernal

pools for parts of their life cycles. Without vernal pools, these species

would disappear from an area!

Most Common Obligate Species found in Wrentham: Wood Frogs, Spotted Salamanders and Fairy Shrimp

Wood Frog

Wood Frog facts• Small size, 1-2.5 in. long• Easily recognized by the

dark mask on its face• Generally lives in the

woods during the year and only goes to a vernal pool to breed in spring

• You can hear wood frog choruses in the early spring.

Life Cycle of the Wood Frog

• Eggs are fist sized jelly masses attached to sticks and twigs. As many as 1500 individual eggs can be in one mass. A pool can have dozens of masses.

• Tadpoles, or larval stage, hatch after about 28 days

• The tadpole develops into a froglet with legs and tails. Part of change or metamorphosis

• Finally, an adult hops out of the pool before the pool dries up in June

• Very few make it to adulthood due to predation

Wood frog egg masses attached to sticks in a vernal pool.

Wood frog tadpoles

Froglet stage(Photo from www.vernalpool.org)

Wood Frog Adult

Spotted Salamanders

Spotted Salamander Facts

• Large… 4-8 in.• Black with bright

yellow spots• Lives under rocks and

tunnels• Rarely seen, yet

plentiful

Spotted Salamander Egg Masses

• Masses of 20-250 eggs attached to sticks in the pool

• Diameter of one mass is a 1-6 inch jelly ball

• Mass is usually clear or white but can turn green with algae growth

Fairy Shrimp

Fairy Shrimp Facts

• Small, .5-1.5 in. crustacean

• Lives only in vernal pools• Swims upside down• Female deposits eggs in

mud before the pool dries up

• Life cycle of only a few months ends when pool dries up

• Fascinating to watch

Other Obligate Species found in Massachusetts

• Spadefoot toad• Blue-spotted

salamander• Jefferson

salamander• Marbled salamander

Vernal pool fact: One blue spotted salamander has been found in Wrentham. No Jefferson or marbled salamanders or spadefoot toads have been reported or found, although they may exist.

Facultative Species

These are species that use vernal pools and other wetland habitats for their

various life activities. A vernal pool is not necessary for their survival.

Facultative Species found in Wrentham Pools

• American toads• Spring peepers• Gray tree frogs• Pickerel frogs• Four toed salamanders• Red spotted newts• Painted turtles• Predaceous diving beetles• Caddisfly log cabins

American Toads

• Fat and 2-4 inches long

• Warty skin• White belly• Eggs layed in pools in

gelatinous strands• Very common

Spring Peeper

• Tiny frog, ½ to 1 in. long

• Sharp peeping choruses can be hear up to ½ mile away!

• Light brown color with “X” on its back

• Difficult to see…camouflaged with forest floor

Gray Tree Frog

• Small, 1-2 ½ in. long• Light gray to brown

color depending on environmental stimuli

• Black lines on back• Inside of legs an

orange color

Pickerel Frog

• Small size, 1-3 in. long

• Identified by anglular brown spots

• Common in vernal pools as well as ponds

• Often in vernal pools to feed

Four Toed Salamander

• Small, reddish brown• 4 toes on each foot• White belly• Constricted tail• Lives in a variety of

wetlands• Rare in Wrentham

Red Spotted Newt

• 3-5 inches long• Completely aquatic• Can live in a variety of

wetlands and even in swimming pools!

• Yellowish brown with red spots with a yellow underside

Painted Turtle

• Common type of “sun” turtle

• Can be seen basking on logs

• Wide, light lines across shell

• Goes to vernal pools to feed

Predaceous Diving Beetle Larvae

• These are predators which feed in a vernal pool

• Larvae can be up to 3 inches long and are often called “toe biters”

• Adults up to an inch long with oval bodies

Caddisfly “log cabin”

• Larva lives inside the cabin

• Cabin acts as camouflage, ballast and protection

• Very plentiful in most pools

• Will eventually emerge as a caddisfly adult

What about Redback Salamanders?

Redback Salamander Facts

• Most common of all the salamanders

• These are terrestrial salamanders meaning they live in the ground

• Can range in color from brown with a red back to black

• Neither obligate nor facultative species

Protection of Vernal Pools in Wrentham

• Certification only establishes that a vernal pool exists.

• Vernal pools are wetlands and wetlands are protected in Massachusetts

• Generally, building and excavation is not allowed within 50 feet of the perimeter of a vernal pool

• Builders will often mark the pool’s perimeter with blue or red ribbons

• Some pools on private land are being destroyed illegally

Science Words Associated with Vernal Pools

• Habitat- Environment used by a plant, animal, or other organism. A redback salamander’s habitat is under a dead log on the forest floor.

• Ecosystem- The organisms in a population and the living and non living things which impact them. Fairy shrimp live in a vernal pool ecosystem.

• Life cycle- The successive stages through which an organism passes from egg or spore to adult. The life cycle of a wood frog goes from egg to froglet to adult.

More Vernal Pool Words

• Larva- Stage of a young insect’s life after it hatches from the egg but before it becomes an adult. A caddisfly log cabin houses the larvae of a caddisfly.

• Metamorphosis- The rapid change from larval to adult stage. A tadpole undergoes metamorphosis before it becomes an adult frog.

• Adaptation- A change in a plant or animal that improves its chances of survival in the existing environment. An adaptation found on the feet of spring peepers is suction cups that allow it to climb easily.

More Life Science Words

• Amphibians- An organism having an early aquatic stage and later developing air breathing lungs as an adult. Wood frogs and spotted salamanders are amphibians.

• Crustacean- a shell covered creature. Fairy shrimp are crustaceans.

• Instinctive behavior- behavior that an organism is born with rather than learned. An instinctive behavior of spotted salamanders is their ability to return to breed in the vernal pools where they were born.

Good Luck Exploring Vernal PoolsGood Luck Exploring Vernal Pools

The EndThe End