CONTENTS
April 1997

Vernal Pools: Here Today, Gone Tomorrow?
Role of Toads in the Schoolyard
How to Make Your Garden Amphibian-Friendly
A Few Safety Tips For Your Pond
Music of the Wetlands: The Calls of Toads and Frogs
Should I Construct A Classroom Aquarium?
Little Green Marvels: Observations of an Environmental Youth Corps Worker
Are Goldfish a Good Idea For Your Pond?
Donation From Ellengale Public School

VERNAL POOLS: HERE TODAY, GONE TOMORROW?

by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

BACKGROUND

Vernal pools are found worldwide, even in "dry" places like Africa and South America. Until recently these temporary ponds were not recognized for their biological value. Vernal pool habitats are now seen as having roles in preserving biological diversity. They provide essential breeding sites for a number of organisms, and support complex food webs.

Vernal means "spring" in Latin. Vernal pools are fed by spring rains and snowmelt, and usually dry out by the end of the summer. These pools are temporary water pools with no permanent outlet, but they CAN have a permanent inlet. Vernal pools are located in basin areas and are formed by the higher land which surrounds them. Some pools also fill from below ground, as the groundwater table rises in the fall. The pools range from a large puddle to a small pond. Other vernal pools hold water for a few years and are considered semi-permanent pools.

Because vernal pools are temporary ponds, they usually dry up annually preventing fish populations from inhabiting and breeding in the area. Some pools are never completely dry, but the shallow water, summer heat, winter freezing, and lack of oxygen keep the pools free of breeding fish populations. The absence of fish in vernal pools means that frogs, toads, salamanders and other wetland creatures find this an ideal habitat (fish love to snack on amphibian larvae).

The same vernal pool observed in three different seasons can appear very different. In winter it may look like a large frozen pond. In spring the pool may be smaller and shallower. In summer it may be hard to believe there was ever a pool at all!

WHY ARE VERNAL POOLS IMPORTANT?

Vernal pools provide habitat for many wetland species, both plant and animal. Animals which frequent vernal pools are classified into either obligate or facultative categories. Obligate species breed exclusively in vernal pools (Spotted salamander, Blue-spotted salamander, Jefferson salamander, Marbled salamander, Wood frogs). Facultative species often breed in non-vernal habitats (Spring peepers, American toads, Four-toed salamanders, Red-spotted newts). Fairy shrimp spend their entire lives in vernal pools.

MASSACHUSETTS

The Natural Heritage and Endangered Species Program (NHESP) of the Massachusetts Division of Fisheries and Wildlife have a program through which local vernal pools are certified. Volunteers must bring a specific pool to the attention of the NHESP. If the pool is located in a contained basin, supports at least one of the obligate species, and does not contain fish, it is certified as a vernal pool. Once certified, vernal pools are mapped so that development projects can steer clear of those specific areas. The organisms which depend on that pool for their survival will be safe from danger. Unfortunately this certification program is only run for Massachusetts. Presently there is no protection for vernal pools in Canada.

Reading Memorial High School students in Massachusetts formed a group called the Vernal Pool Association. Their objective is to promote the study, enjoyment, and conservation of vernal pools. The group coordinates workshops and creates educational materials. The goal of the Vernal Pool Association is to study and certify vernal pools. "Wicked Big Puddles" is a publication of Reading Memorial High School, as well as a pamphlet entitled "Vernal Pool Identification". These two sources of information were funded by The United States Environmental Protection Agency, and produced by Leo Kenney, a science teacher at Reading Memorial High School.

Massachusetts Wetlands Protection Act

Vernal pools are considered existent only if they are certified and mapped. If they are not mapped, there is no stopping development of the site. The Massachusetts Wetlands Protection Act came into effect on November 1, 1987. Vernal pool habitats were given "automatic protection" if: 1) certified by Massachusetts Division of Fisheries and Wildlife 2) occurs within "Wetland Resource Area".

CANADA

Presently there is no protection specifically for vernal pools in Canada. However, there is a Federal Policy on Wetland Conservation in existence. The objective of the policy is to "promote the conservation of Canada's wetlands to sustain their ecological and socio-economical functions, now and in the future." Seven strategies are outlined in the policy, as follows:
1: Develop public awareness.
2: Managing wetlands on federal lnds and waters in other federal programs.
3: Promote wetland conservation in federal protected areas.
4: Enhancing cooperation.
5: Conserving wetlands of significance to Canadians.
6: Ensuring a sound scientific basis for policy.
7: Promoting international relations.

Some Canadian wetlands are considered internationally important under "Ramsar" criteria. The Ramsar Convention (also called the Convention on Wetlands of International Importance) is held annually and involves countries worldwide. Wetlands of international importance must meet certain criteria before they are recognized. The wetlands can be considered internationally important based on uniqueness, plants and animals, or waterfowl. When a wetland is Ramsar designated, this elevates the prominence of the site, and promotes conservation needs and research and education of wetland values. Canada joined the Ramsar convention in 1981, and presently has 30 wetlands designated internationally important.

SOME TIPS FOR IDENTIFYING VERNAL POOLS

Winter : no deeper than about 1 metre
: no stream flowing out of pool
: large area of ice
: common wetland plants (cattails, sedge) protruding from ice
: situated in a basin

Spring : same as winter, except ice is most likely melted
: sounds of frog calls
: presence of eggs and larvae of obligate species

COMMON INVERTEBRATES

  • Giant waterbug
  • Damselfly nymph
  • Water boatman
  • Diving beetle
  • Water scorpion
  • Dragonfly nymph

OTHER SPECIES FOUND IN BUT NOT EXCLUSIVE TO VERNAL POOLS

  • Gray treefrog
  • Diving beetles
  • Green frog
  • Whirligig beetles
  • Fowler's toad
  • Dobsonflies
  • freshwater clams
  • Caddisflies
  • Painted turtles
  • Damselflies
  • Water scorpions
  • amphibious air-breathing snails
  • Snapping turtles
  • dragonflies
  • leeches

HOW YOU CAN HELP VERNAL POOLS

1: Locate and protect vernal pools in your area. Libraries may have local maps which show locations of vernal pools.
2: Use a vernal pool as an "outdoor classroom".
3: Conduct a town-wide vernal pool inventory. Check with landowners to see if you can investigate sites. Sketch vernal pools found and list species observed. Photograph or tape evidence of the existence of a vernal pool. Make a map of the vernal pools you discover. Send this information to the Metro Toronto Zoo.

 

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ROLE OF TOADS IN THE SCHOOLYARD
by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

Sure, they may not be cute, may not feel warm and cuddly, but toads do have some extremely positive characteristics. For instance, toads are one of the most beneficial animals in your schoolyard garden, keeping your unwanted insect problems under control!

One toad eats 3 times its weight in insects every day. That adds up to tens of thousands of insects a year! A toad's diet is composed of 81% pesky insects. Bob Johnson, Curator of Reptiles and Amphibians at the Metro Toronto Zoo, has conducted studies which prove a single toad eats up to 1500 earwigs in one summer. You mean someone actually liKES earwigs?! Toads are active at night, and are attracted to lights because that's where the bugs hang out! However, DO NOT place a light in your garden to attract amphibians because you will also attract insects that destroy your garden.

Worried about toads eating your garden? Don't worry... be happy. Toads are carnivorous, so they won't touch your garden plants. Go ahead, let a corner of your garden grow "wild". Give a toad free room and board in exchange for freeing you of your insect problems!

Some of the pests that toads eat are (deep breath) Gypsy moths, Armyworms, Wireworms, caterpillars, grasshoppers, Potato beetles, slugs, snails, sowbugs, ants, cutworms, flies, Pill bugs, centipedes, millipedes, Mole crickets, and of course earwigs. Quite a healthy appetite!

A number of companies advertising "natural pest controls" are selling toads as a means of controlling insects in gardens. Toads should not be purchased for a number of reasons. The purchased toads may not be indigenous to your region, posing a threat to native amphibian species through predation and disease. Secondly, your neighbourhood may not contain the habitats toads require to survive.

Frogs

Frogs need to be close to a permanent water source (lakes, rivers, ponds). They need a more constant supply of moisture because their skin is very porous and dries out quicker. Large bodies of water are also a necessity for laying eggs. Frogs are a little more picky about where they live, but they are known to feast on a variety of insects.

Salamanders

Salamanders prefer to live in woodlands, but they will visit your garden. Salamanders like to munch on slugs, grubs, worms, spiders, beetles, ants and mosquitos. There are a few conditions that must be met before this amphibian will help you with your pest problems. Salamanders prefer "natural" gardens that are not constantly being cared for, damp piles of rotting logs or stones.

HOW TO MAKE YOUR GARDEN AMPHIBIAN-FRIENDLY

The requirements are moisture, shady shelter and a pesticide-free garden. Amphibians have very sensitive skin, and if vegetation is sprayed with herbicides or pesticides they will absorb these toxins through their skin and possibly die.

Toads really enjoy burrowing. Hay, straw or mowed grass is ideal for toads to have some fun. Bushy plants are an asset since toads need shade.

There are terra cotta toad houses on the market. A broken clay flower pot with a "toad hole" chipped out of it is also perfect for toads. The clay absorbs moisture and provides a damp, cool shelter. Other good ideas are rock arrangements or pieces of wood that form hollow and dark spaces, fern groves and rotten wood.

For more information on how to make your schoolyard amphibian-friendly please refer to the Adopt-A-Pond programme's book "The Urban Outback - Wetlands for Wildlife".

 

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A FEW SAFETY TIPS FOR YOUR POND
by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

Building a pond in your schoolyard is a fun and rewarding experience for the whole school. The curious nature of children will attract them to new features in their schoolyard/backyard. As a result, it is best to take precautions as to avoid any unwanted incidents. Here are a few safety tips for your pond:

- Construct a natural looking fence and gate around your pond.
- Place large rocks in the pond to restrict access to the deep end which also creates shelter for amphibians.
- Erect signs warning of the existence of the pond.
- Build a shallow pond (less than 1 meter at deepest point), if the pond is situated in an area frequented by children.
- Construct a berm three-quarters of the way around the pond (at deepest end) and plant with dense vegetation, restricting access to the pond at the shallowest end.

The best way to avoid accidents around your pond is to teach your students water safety. Some schools in Ontario are built beside wetlands, and they must deal with water safety issues on a daily basis. In addition, neighbourhoods are filled with water (streams, stormwater detention ponds, swimming pools), reinforcing the importance of teaching water safety.

Ponds can be a great hands-on resource for schoolchildren who are aware of water safety issues. If you have any questions or suggestions, please feel free to write us at any time. We are always happy to hear from you.

MUSIC OF THE WETLANDS: THE CALLS OF TOADS AND FROGS
by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

BACKGROUND

Ontario has eleven species of toads and frogs. These amphibians hibernate on land or underwater, and emerge in March and early April. American toads, Fowler's toads, Wood frogs, Spring peepers, Chorus frogs, and Gray treefrogs hibernate on land. Leopard frogs, Pickerel frogs, Mink frogs, Green frogs, and Bullfrogs winter underwater.

Frogs and toads begin to call once the water temperature reaches a certain level. Calling starts earlier in ponds that are exposed to sunlight. These ponds become warmer sooner than those found in shady, cooler areas. Frogs and toads in southern Ontario start calling and laying eggs about a month before those in northern and central Ontario.

Only males have vocal pouches. These pouches can be single or paired. Single pouches are located under the throat, and paired pouches are located on each side of the head. The pouch fills with air and acts as a resonator to project the call. Each species has its own unique call.

HOW CAN YOU HELP THE FROGS AND TOADS OF ONTARIO?

1) Protect/restore a wetland habitat. Visit a local marsh, stream, or pond to observe different types of amphibians. You have now "adopted" a pond! If you let us know about your visit, we will send you a certificate of appreciation from the Amphibian Interest Group.

2) Participate in one of the Canadian Wildlife Service's Amphibian Monitoring programmes:
a) Backyard Frog Surveys: For people who live by a wetland and do not want the bother of driving to a separate location and counting frogs.
b) Road Call Counts: For people who want to participate but don't live near a large marsh.
c) Marsh Monitoring: For people living near marshes, especially shoreline wetlands of the Great Lakes which are Areas of Concern; to attempt to involve "birders" who do marsh bird monitoring surveys in marshes.

For more information please contact the Canadian Wildlife Service at the address below:

Canadian Wildlife Service
Environment Canada
Canada Centre for Inland Waters
867 Lakeshore Rd.
PO Box 5050
Burlington, ON
L7R 4A6
Phone: (905) 336-4968 Fax: (905) 336-6434

 

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FACTS ON THE CALLS OF FROGS AND TOADS

 

Name Favourite Calling Spots Description of Call When They Call
Spring Peeper grass clumps, leaves at edge of pond, low overhanging branches, floating twigs loud peep... peep... peep March, April, May; September, October on rainy nights
Wood Frog floating vegetation, thickets at edge of temporary pools duck-like quacking last week of March to first week of April
Striped Chorus Frog clumps of grass, floating cattails, dogwood twigs thumb running along teeth of plastic comb March and April
American Toad along shoreline, logs, floating leaves 15-20 second long continuous trill April and May
Northern Leopard Frog float on surface of water, floating vegetation wet hands rubbing on wet balloon April and May
Pickerel Frog streams, flooded ditches weak call, like distant snoring May
Fowler's Toad Canada: only found on shore of Lake Erie short trill May and June
Gray Treefrog perches on willow, dogwood, cattails, trees, clumps of sedges near pond loud blurting trill that lasts two seconds end of May until end of June; August, September on wet, humid nights
Green Frog banks of ponds and rivers, on rocks and logs "twang" of banjo string June and July
Mink Frog lily pads, surface of water hammering June and July
Bullfrog pick favourite spot or float on surface of water Jug O'Rum... Jug O'Rum June and July

For more detailed information on the life cycle and natural history of each frog, and to hear frog calls online, visit our Amphibians of Ontario page at http://www.torontozoo.com/adoptapond/aoo/aoo.html.

 

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SHOULD I CONStrUCT A CLASSROOM AQUARIUM?
by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

Classroom aquariums are great hands-on resource for schoolchildren. Everyone in the classroom can get involved in setting up the aquarium, making daily observations of the wetland ecosystem and/or fundraising for the purchase of an aquarium.

Steps for Creating an Indoor Pond:

Bring 5 pails and a dip net to a local pond:

Pail 1 - pond water
Pail 2 - floating plants, algae, water, submergent plants
Pail 3 - invertebrates (eg. water boatmen), 10-15 snails
Pail 4 - bottom mud
Pail 5 - clean sand and gravel

Back in the Classroom:

1: Place aquarium in a well-lit area, but not in the path of direct sunlight.
2: Spread clean sand and gravel in aquarium.
3: Add small layer of bottom mud.
4: Add water slowly to reduce mixing. Tap water that has been sitting out for at least 2 days can be added if necessary.
5: Let pond settle.
6: Add plants and invertebrates.
7: Watch your ecosystem grow!

We DO NOT recommend transferring amphibians (eggs, tadpoles or adults) from local wetlands because they have specific habitat requirements which are difficult to simulate in an artificial environment. Individual amphibians usually breed and hibernate in the same location every spring and fall respectively. When they are taken from their natural environment they lose their bearings and become disorientated, reducing their chances of survival when re-introduced. Any animal that is caught and used for study should be released at the site where it was found.

We DO recommend taking field trips and visiting wetland wildlife in their natural habitat. This gives children and teachers a chance to experience the abundance of life in wetlands and see Mother Nature in all her element.

liTTLE GREEN MARVELS: OBSERVATIONS OF AN ENVIRONMENTAL YOUTH CORPS WORKER
By: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

Lately I have come to see frogs in a different light other than something fun to try and catch. I have learned so much about amphibians in the last two weeks. I am working on the Adopt-A-Pond programme, assisting Heather Gosselin (Coordinator), under the supervision of Bob Johnson (Curator of Amphibians and Reptiles).

Did you know there are four different types of amphibians? Frogs, toads, newts and salamanders. I made sure to learn this first, because when asked to name one at my interview my response was "Um...snakes...turtles...um" I was VERY wrong, and surprised I was hired!

Did you know that each species of frog and toad have their own unique call during mating season? After two days on the job I went camping. My friends and I were debating on whether it was ducks or frogs we heard all night long. So when I returned home I listened to my "frog tape" which Heather gave to me. Sure enough, it was green frogs we had heard!

Did you know that frogs and toads eat their own skin? Yep, it's gross but true. Amphibians shed their skin once a week.

Did you know amphibians are disappearing throughout North America? The destruction of wetlands also causes the destruction of amphibians. Frogs, toads, newts and salamanders are in trouble! The Adopt-A-Pond programme has a goal of involving all 5000 schools in Ontario in wetland conservation. 1200 schools are involved to date. Some schools have built ponds right in their schoolyards, some have saved local wetlands from development, and some have simply visited and observed a wetland as a part of their curriculum. Every bit counts.

Wetlands hold great importance to our global ecosystem. They provide homes for many plants and animals, "clean" water that passes through them, and prevent flooding and erosion. That's a big job! So we should help all we can.

When people ask me what I do at the zoo, I say "Help save the frogs." I've come to realize that frogs are important too. Hey, they eat mosquitos! That's all the reason I need!

ARE GOLDFISH A GOOD IDEA FOR YOUR POND?
by: Anna Collier
Environmental Youth Corps
Adopt-A-Pond Assistant

Yes, goldfish (carp) are ornamental and fun to watch as they swim in the water, but there are many drawbacks to having carp in your pond. They uproot plants, eat amphibian eggs, and cloud the pond water. Carp are omnivorous and eat both plants and animals.

Both emergent and submergent plants are important sources of food and shelter for wetland wildlife, and are crucial for controlling algae. These plants absorb some of the nutrients, and block out the sunlight necessary for algal growth. Carp eat aquatic plants and uproot them as they feed on the bottom mud.

Goldfish can be removed from a pond after introduction. They should be caught and placed in an aquarium, or have another pond built exclusively for fish. DO NOT flush fish out of the pond, or release them in natural waterways as this will disturb the native fish species and possibly expose them to pathogens. After the fish are transferred, be sure to drain or dry the pond to remove the spawn and fry that remain.

If you REALLY want fish in your pond, one fish will limit impact on the pond ecosystem.

DONATION FROM ELLENGALE PUBliC SCHOOL

Students from Ellengale Public School in Mississauga, Ontario, recently raised money for the Adopt-A-Pond programme. Grades four and five students, under the guidance of Stephanie Garcia, their teacher, gathered their old toys together and had a sale. The children learned about wetlands in the classroom and decided they wanted to help in their own special way. Thank you Ellengale Public School!

 

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