Wetland Birds: Great Blue Herons

If you have the chance to visit a wetland, you might see some interesting birds. Wetland birds have special adaptations to live in these wet places. One of my favorite wetland birds is the great blue heron.




This great blue heron was right next to the Chesapeake Bay on Kent Island, Maryland. At first I thought it was a statue--until it moved! Notice how the heron has a long beak and long, skinny legs. Herons like to stand in shallow water and watch for fish. Then, they spear them with their sharp beaks. They swallow the fish whole.



In the picture below, you can see another heron. This one was at a salt marsh near Ocean City. I watched this heron for about half an hour as it took a step, watched for fish, and caught them. I saw it swallow about three fish in the time that I watched it. But herons don't eat just fish--they'll also feed on water insects, frogs, shrimp, and just about anything else that it can find in its habitat.

Herons are often easy to see. You don't have to make a trek to some wild and remote place. Herons come to creeks, ponds, rivers, man-made ponds, and even drainage ditches. As I ride in the car, I like to look for herons. I can catch a glimpse of one at least once a week.

As you ride across a bridge, look out the window at the river or creek below--you might just see a heron standing there, waiting to catch some fish.

More on Mole Crabs

Thanks for all of the comments about mole crabs! My students and I enjoyed reading the comments. Several of you had some great questions about the little crabs. Here are some answers.

How big do they get?
The mole crabs that we find at the beach (Ocean City, Maryland or Assateague) are usually 1.5 inches or less. You can see Zachary holding one in the picture. That's one of the bigger ones that we found. The smaller ones are about .5 inches.

Can they live in Lake Erie?
I don't think so. It's my understanding that they are saltwater creatures. Lake Erie, as you know, is freshwater. But I'd love to research and find out more.


Can mole crabs be different colors? 
Life is tough if you are a tiny (and delicious) little crab. Why do you think that mole crabs are the color that they are? Where might you find mole crabs that have different colors?

Why do mole crabs stay in wet sand?

Good question! The mole crabs are filter feeders. They stay close to the waves because they put their antennae up to feed when a wave comes by. Because this is how they eat, they like to stay in the wet sand.

Why are they called mole crabs?
When I started researching them, I was actually surprised to find that this is their most well-known name. We always called them "sand crabs" when I was growing up.

But the name makes sense. If you happen to be at the beach while they are digging down into the sand, they do look like moles digging into the ground. Moles dig, and these crabs dig, so the name fits!

A Special Vernal Pool

A vernal pool is a pool that is wet through the spring, but dries up in the summer. Vernal pools are special habitats. They can be homes to wood frogs, spotted salamanders, and fairy shrimp.

On the last weekend in May, I found an interesting new vernal pool! Can you tell what has happened? The old tree fell over, probably during the winter. In the hole that was left behind, a vernal pool has formed. This pool is nice and shady, perfect for small creatures.

But had any creatures come to this vernal pool? I poked around a bit to find out. There, in the middle of the pool, I saw a baseball-shaped blob of eggs! Salamander or wood frog? They were a little too far away to tell--and I didn't want to reach into the pool to find out.

What was so neat is that this vernal pool had not been here last year. It's brand-new! It just shows how things in the forest are always changing--and when one thing goes away, like the old oak tree, something new can take its place.

Salamander Search

Spring is a great time of year to look for salamanders! Salamanders are a kind of amphibian. They have smooth skin, no teeth, and no claws.

Salamanders need to keep their skin moist. As a result, they live in wet places. Some salamanders spend their whole lives in the water. Others live in moist spots, like under rotting logs.

A redback salamander

We peeked under a rotting log this weekend to find the salamander to your right. If you are looking for salamanders, be very careful. Lots of creatures live under rotting logs--and not all of them are friendly! We found earthworms, some millipedes, and a centipede with this salamander.

Salamander eggs????

If you are looking for salamanders in Pennsylvania, you'll probably find plenty of redback salamanders like this one. These salamanders can be tricky to identify, as you might see some in their "lead" phase. These don't have the red line down their backs.

We found these eggs under the same log as the redback salamander. Redback salamanders spend their lives on land, and the mother is known to guard the eggs. While it's quite possible that these eggs are the redback salamander eggs, I'm not entirely sure.

Wood Frog Eggs

A trip to the vernal pool yesterday revealed masses of wood frog eggs. These eggs can often be found in vernal pools. Here's what they look like:

Do you see the little black circles? Those will get longer over the next few weeks, and slowly develop into tiny tadpoles that look like this.

Over the rest of the spring, the tadpoles will grow. Eventually they will become tiny froglets.

Wood frogs are pretty common in Pennsylvania. A full-grown wood frog is shown below. Do you notice the robber's mask?

Lotic Water Habitats

What does the word lotic mean? Bodies of water that are lotic are moving. Rivers, streams, and creeks are all lotic.

Lotic habitats can be fun to explore. Try throwing a stick into the water. What happens? The current pulls it away from you! Investigate the current. Is it the same in every part of the stream? Are there places where the current is faster or slower?

The water in a lotic habitat is always moving. But not all parts of a stream move in the same way. In some places, the water moves slowly; in other places it can run more quickly. When water runs swiftly over rocks, it forms riffles. Riffles are often a sign of good water quality in a stream.

Do you see the riffles in this stream? Look for the water that is moving quickly.

Would you like to live where the water is always moving? There are some creatures that call these places home. Try gathering up some leaves or rocks from a stream. (Be sure to ask a grown-up to help.) What can you find? Here is a mayfly nymph found crawling on the bottom of a stone in a mountain stream. Notice its three tails.

This mayfly nymph is only about 2 centimeters long.

If you find any creatures in a stream, be sure to observe them carefully, and then put them back exactly where you found them. Life in a lotic habitat is tough enough--we don't need to make it any harder!

Have you ever visited a lotic habitat? What did you notice?

First Flowers of Spring

What kinds of flowers can you find in the spring? Springtime ephemerals are flowers that bloom for a short time. These flowers take advantage of the sunny days in the forest. They bloom before the leaves come out on the trees.

Dutchman's Breeches

Springtime ephemerals are usually on the small side. But they are quite beautiful! The flower above is called Dutchman's breeches. The word breeches is an old-fashioned word for pants. Can you see how the flower got its name?