Frogs and fairy shrimp and salamanders, oh my!

Did you hear the sound of a thumb raking over the teeth of a comb while on a recent hike? That's the Western Chorus Frog. The first frog to emerge when the ground thaws.

They are very loud near some wetlands in our area, particularly in the Alden region where small, fishless ponds (vernal pools) abound this time of the year. A diversity of tiny creatures, such as the fairy shrimp (photo to the right), are found in abundance, providing a valuable food source for the recently emerged amphibians, as well as the hatchling salamanders, frogs, toads and turtles.

In larger ponds - those with fish - these small creatures do not survive, as they become food for the fish. But, in the small temporary pools of spring, the young amphibians are able to mature, feed on mosquito larvae, and breed so there will be future generations!

If you live near one of these spring pools, be on the lookout for spotted salamanders! They have a tendency to end up in window wells - the three on the left were rescued from one during a spring hike to look at vernal pools and the critters found there!

Vernal Pools are Teeming with Life!

That's a crayfish, and last Friday, we saw several tiny, immature crayfish in vernal pools up in Alden Township. They were so tiny that the claws were about the width of a strand of hair! The entire critter was perhaps a quarter of an inch long, looking like some random bug larva, but under a magnifying glass, it became clear that these little guys were teeny-tiny crayfish!

A project to gather information about our local vernal pools has been organized by George Johnson, formerly of Alden Township but now living in Madison Wisconsin. One of the things that George had always hoped to accomplish when he lived in McHenry County, was to raise awareness of the presence and importance of these local temporary, spring ponds.

These seasonally wet areas are uncommon in the Chicago region, in large part because they are places that are filled in by homeowners and developers who do not see the benefits of having a wet, mucky spot in the yard each spring and perhaps into the summer.

The spring ponds are fairly common in Alden Township for a couple of reasons: 1. the area is still sparsely developed, and 2. historically, much of the area was used for livestock grazing instead of row crop farming. This meant that the seasonally wet spots survived, along with a lot of critters that are not often seen in the "suburbs."

Friday April 3rd was the inaugural day of McHenry County vernal pool monitoring. During their pool sampling, volunteers saw a large number of fairy shrimp (ranging in color from pink to red to blue to yellow, and everything in between), a wide variety of midges, scuds, and other tiny aquatic life that plays an important role in the overall food chain.

It was a cold day -- 43 degrees in the sun. The water was cold too -- 45 degrees. Yet, when we gazed into our dipping nets as we pulled them from the pools, tiny little eyes looked back at us! I had no idea there was so much activity on a cold day in cold water!

Unfortunately, there were also lots of mosquito larvae. These are another link in the web of life, providing a food source for dragonflies, frogs, fish, birds and other species that feed on water organisms, but I still don't like them. The skeeter larvae spend most of their time at the surface of the water breathing through a tube in their abdomen, as shown in the picture.

The eggs from which the larvae hatched were probably laid in the damp ground last summer or fall, and remained in an embryonic form until conditions were right for them to develop into larvae. The larval stage lasts a week or two, then turns into a pupa for a couple of days -- just long enough for it to become a fully-formed adult mosquito, ready to start feeding...

Now, don't blame the vernal pool for the mosquito larvae. These guys will develop in any little wet spot, regardless of the habitat. Lawns, bird baths, potholes in the road, etc. If it holds water for even a few days, it can be a source of skeeters!

One of the beautiful things about these vernal pools is that they are literally teeming with life of all shapes and sizes. There are microscopic things being eaten by tiny critters, which in turn are eaten by somewhat larger things, etc, etc. In that chain are tadpoles, young frogs and salamanders that eat mosquito larvae.

My wish is that there will be a large number of frog and salamander babies in all of our local vernal pools to eat those larvae before they become adults!

Amphibians Under Threat

The April 2009 issue of National Geographic Magazine has an article about the dramatic, worldwide decline of amphibians (frogs and salamanders) due to a fungus that has been spreading rapidly over the last couple of decades.

The fungus, chytridiomycosis, targets the protein keratin which increases in frogs as they mature. So, a pond with the fungus may be teeming with tadpoles, but have no adult frogs. (And once those frogs mature, they will die too, and then the source of future tadpoles is gone...)

Even areas that are remote from civilization, like lakes high up in the Sierra mountains, have seen devastating die offs of frogs as the fungus has reached those seemingly isolated spots. The following quote seems to sum up the problem:

" 'Today's amphibians have taken not just a one-two punch, but a one-two-three-four punch. It's death by a thousand cuts,' says University of California, Berkeley, biol­ogist David Wake. Habitat destruc­tion, the introduction of exotic species, commercial exploitation, and water pollution are working in concert to decimate the world's amphibians."

Add to these other items the spread of the chytrid fungus, and the population of frogs and salamanders across the planet are in trouble. Hundreds of species have already gone extinct. Many other species are now found only in captivity, where scientists hope they can keep them around through breeding programs, and then reintroduce them to the wild once (if?) the situation with the fungus is resolved.

"Why care about frogs? 'I could give you a thousand reasons,' says herpetologist Luis Coloma. Because their skin acts not only as a protective barrier but also as a lung and a kidney, they can provide an early warning of pollutants. Their insect prey carries human pathogens, so frogs are an ally against disease. They serve as food for snakes, birds, even humans, playing a key role in both freshwater and terrestrial ecosystems. 'There are places where the biomass of amphibians was once higher than all other vertebrates combined,' says David Wake. 'How can you take that out of the ecosystem without changing it in a major way? There will be ecological consequences that we haven't yet grasped.' "

It all goes back to Aldo Leopold's rule about intelligent tinkering: be sure you keep all the parts.

For a quick slide show of frogs from around the world, click here!

Have you Hugged Your Salamander Today?

Meet the Tiger Salamander Ambystoma tigrinum, one of the few salamader species found in McHenry County. Our local Tigers can be as large as 14 inches, but are more likely to be 6-8 inches long. You are most likely to find one of these guys in a moist woodland under leaf litter - they tend to be very private, probably to avoid predators!

There are about 500 species of salamader worldwide, with the largest type found in China, and weighing in at 140 pounds and nearly 6 feet long!

In Illinois, the largest salamander is called a Hellbender, and can be two and a half feet long. They are found in fast moving streams in the southern part of the state, so don't expect to see one in McHenry County!

The Great Smoky Mountain National Park in North Carolina is considered the salamander capital of the World, boasting 30 different species ranging from the inch and a half long pygmy salamander to the 30 inch hellbender!

Salamanders are amphibians, meaning they spend part of their life on the land and part in the water. They are most closely related to frogs and toads, although they may visually resemble lizards (or snakes with little feet). Their skin must be kept moist or they dry up and die.

Many, but not all, salamanders breathe through their skin, making them highly susceptible to pollutants like pesticides or other chemicals, as these things are absorbed directly through the skin and into the organs.

Salamanders fill an important niche in the overall food chain. They are carnivores, meaning they eat other animals like insects, eggs, small fish, and even small rodents or young frogs. In turn, they are eaten by raccoons, possums, large birds like herons and hawks, snakes, turtles and other medium-sized carnivores.

Following the first big rain in the spring, when temporary pools of water flood, salamanders emerge from hibernation, and head out in search of something to eat and a place where they can meet salamanders of the opposite gender! This drive to reproduce often results in so-called "breeding events" in the temporary pools, where several salamanders gather to lay and fertilize eggs. (Kind of a salamander orgy.)

However, because the salamander is a small, reclusive critter, any given salamander is unlikely to have the opportunity to breed more than once in its lifeime! So, if you happen to chance upon a salamander breeding event in your local vernal pool one spring, just look away, and let them enjoy the party -- it might be the only party any of them ever attend!