Egg Update

Learning about metamorphosis, or change, is such a rite of spring that many school children have done the whole tadpole thing four or five times by the end of third grade. Tadpoles are pretty sturdy and easy to acquire so teachers are assured that things will proceed in a predictable manner. Jumping on that bandwagon, I planned to do tadpoles with the preschoolers at Messy Fingers in April. Eggs, tadpoles, frogs seemed like a nice logical way to celebrate spring science.

So I expected my eggs,  collected in our pond just like the previous six springs, to proceed in a standard sort of fashion turning into tadpoles and then getting legs... well you know the drill. But here is where science took over.

The eggs seemed be in a much smaller mass than usual so I was concerned that something bad was happening. And the mass was thicker feeling but that could have been the cold, I thought.

The eggs hatched right at Messy Fingers much to the excitement of the parents.  But the "tadpoles" didn't seem behave in the usual way. They were jumpier almost more fish like in their movements. A week later, it was very very clear what critters I had in my container.

Salamanders.

The external gills are a clear giveaway. Now this isn't entirely unexpected for two reasons. First every spring we hear wood frogs calling and they are an obligate species for vernal pools. Now that is a lot of big words and new ideas for one sentence. Vernal pools are ponds that are generally wet only in the spring so no fish live in them. This special wetland area is home to many unusual species that are obligate species, meaning they can only breed in a vernal pool.

And second, we found a baby spotted salamander in our back yard two years ago. They don't travel far from their birthplace and are also an obligate species.

Check out this website from Maine on Vernal Pools. They have a great coloring page comparing frogs and salamander life cycles.

The babies are going to have to go back to the pond very soon. Salamanders use the chemistry of the pond to find it again when they are adults and will only lay eggs in the pond they hatched in. I've been very careful to only put water from that pond in their tank.

Happy Earth Day and...

something is happening to our frog eggs.  After spending time away this weekend, I checked on the babies. This is what I found.

Instead of little spheres in the eggs, there are little comma shapes in them.

So what does this mean?

It means that the eggs hatches and the frog babies are now embryos. They are starting to look like something, but it could be anything!

Here is a close up and can see that they do look like embryos - there is a darker backbone and a head. They are going to be living off the yoke of the egg for a while. Frog eggs spend about three weeks as embryos so we should have tadpoles soon!

Guests

These are some of the guests we had at the library today. They helped us learn about metamorphosis. Metamorphosis means to change and these little guys change into tadpoles and then in to frogs.

I borrowed these frog eggs from a pond behind my house. Not the big pond but a much smaller pond nearby. Every spring, or least since I've live here, we've found frog eggs in the pond. This year there were about the same number of masses as usual, but each mass was smaller. In the past, there were hundreds of eggs per mass and now, as you can see, the number is much smaller. Yep, that is an entire mass in the picture ~ about 30-40 eggs.

I will hatch these babies and keep you informed. Before they get their back legs I will return them to their home pond and hopefully listen to their mating song next spring. 

Want to get your own eggs or tadpoles? Check out this blog post on some guidelines for keeping tadpoles.

Fun Friday Fact

Bull frogs gulp their dinner in mid leap. They open their mouths and can grab prey as they jump.

Bull frogs were named because their call sounds a bit like a cow.

Animal of the Week: Bullfrog

Bullfrogs live in the eastern portion of North America and can be found livening up the nighttime symphony with their deep "jug-o-rum" calls.

These guys love to live in ponds and lakes and will eat anything they can get their mouth around. They are as omnivorous as it comes eating fish, grubs, insects, and even other frogs. What about plants, I hear you say? Well, when these guys are tadpoles they eat algae when young and will take on larger prey when they are large enough.

The tadpoles can live two years in a pond before metamorphosing in to frogs. They have big tadpoles and it is worth trolling murky waters with a net this year just to see them. They are fairly dark compared to other more petite tadpoles.

And these guys are actually farmed in the south as a food source. Yum, eh?

Fun Friday Fact

A group of frogs is called an Army of Frogs!

And most frogs are already in camouflage. How cool is that?

Book Review: From Tadpole to Frog

From Tadpole to Frog by Wendy Pfeffer.

This is part of the Let's Read and Find Out Science series and Level 1 books are designed for preschool and kindergarten aged kids. They are great books in general and this is no exception. The vocabulary might be a bit tricky for most beginning readers, but we all need a little help from time to time with big science words.

This book has illustrations rather than photos. I do prefer photos for non-fiction but these pictures are well-done and accurate.

4/5 stars.

How to: Keep Tadpoles

Keeping tadpoles is easy. You need a container to keep them in. I like to see them so a clear-sided container is a must for me. Make sure it is clean and well rinsed. Keep the container in an area away from direct sun so it doesn't get too hot. I like glass because it is durable, but I have used plastic bug houses like this for short visits. They are quite inexpensive and have nice handles for transport.

Just about any pond in southern New England, where I am, has frog eggs in early April and tadpoles in May and June. Check along the edges along branches or plants growing out of the water. Use a small bucket or a pan taped to a pole to reach farther into the water.

Gently scoop out some pond muck and check for tadpoles. They generally move around quite a bit after you’ve scooped the water. Be sure to take algae and plant material from the same pond to feed the tadpoles.

No matter what you collect, put them back in their home when they have legs and still have a tail. They need to re-acclimate to their home before leaving the pond.

Animal of the Week

Green frog - image from Bug Girl's Blog - http://membracid.wordpress.com/

It is National Frog Month and this week we are celebrating FROGS!

Frogs are an important part of our ecosystem. They eat bugs - and that is just one of the things that is really important about them. Frogs breath through their skin as well as their lungs. Chemicals or pollution in water ways can damage or kill frogs. They warn us about environmental problems that are water related.

And they are just so darn cool.

Mama frogs lay eggs in ponds, lakes, puddles, and in some places, in flowers. The eggs hatch and become tadpoles. Then they need to become frogs to hop out of the water.

Frogs come in all sorts of colors. The one at the top of the page is a Green Frog, but frogs can be red, yellow, green, blue, brown, orange, and even purple.

Tadpole Setup

I scooped up tadpoles and water a few weeks ago and here are some pictures. The tadpole here looks HUGE but it is just the water magnifying it. This is my tank - and my fancy stand! I like it a bit off the ground mostly because it causes the kids to look in it more often. I need to scoop a few more tadpoles into the tank - we can only find three.

I love the screened lid on the tank. That has kept some of the needles and leaves out of the tank but it still lets in plenty of rain and air. We are going to put a rock in the tank soon. My kids area convinced that one year, our tadpoles will turn into frogs unexpectedly and need to hop out. We've always put them back into the pond while they've had tails to give them time to readjust to the pond.

April in National Frog Month

April is the perfect time to learn about frogs! Frogs are amphibians and undergo metamorphosis - or change - from egg to frog. Right now the easiest way to find frogs is to catch them as tadpoles.

Keeping tadpoles is pretty easy. I use a clear container so I can see them easily - I am just that kind of girl - I don't want to miss anything! I scoop water from the pond so that it includes some of the mucky stuff at the bottom and a few tadpoles. I put this in my tank - that I got from a generous freecycler (www.freecycle.com) and keep it in the shade. The muck has plenty of algae - the green slime that the tadpoles eat. Yum!

Over the next few months they will turn in to polliwogs - getting front legs followed by back legs and finally absorbing their tail and turning in to real frogs. I always get them back to their home pond before their tail is totally absorbed so they learn the smell of home. This will help them next year when they are frogs ready to lay eggs.

This is a rite of spring in our house. My 6 year old got her first turn to actually walk in to the pond and scoop this year. We call this tiny pond Three Tire Pond - and sadly that should be changed to Five Tire Pond with new trash showing up this year. We will go in this fall and pull them out and send them to the recyclers.

Ribbit!