Around the first week of October for about a two week span I began to notice little black critters slowly trying to cross roads near ponds or wetlands. Often they were traveling away from a body of water. While assisting these creatures across, probably the most dangerous task they experience during their life; I recognized that these little black critters where tiger salamanders, or as my son would call them "lizards." These smooth, wet skinned salamanders resemble a lizard, but they are an amphibian and a lizard is a reptile.
As many of you probably know an amphibian is an animal that lives part of its life in the water and the other part on land. Other examples of amphibians are frogs or toads. Amphibians must lay their eggs in water; after hatching the young stay in a larval stage for a period of time before maturing into an adult. In the larval stage they have gills to obtain oxygen from the water; they look almost fish-like. Once fully developed the adults develop lungs to breath. With the development complete the salamander and other amphibians leave the water.
The term amphibian migration is probably not the correct term for amphibians traveling to or from water, but it sounded good to me. Unlike waterfowl migration where these birds are traveling thousands of miles, some amphibians may only be traveling a few feet. The tiger salamander on the other hand may travel a longer distance. With this occurring during a few weeks in the spring and in the fall it is a rare time to actually witness a salamander in the open.
Salamanders are a quiet a secretive animal; they generally only come out at night. They live in moist areas or often in burrows up to two feet in the ground. People may be surprised by how many salamanders exist. In some moist woods scientists estimate that there are more salamanders than birds and mammals combined! Since they live in burrows or under leaves and logs they go unnoticed. The tiger salamander is the largest salamander found on land and can grow up to a foot in length. Adult tiger salamanders feed on worms, insects, and other small animals. One interesting fact about young salamanders is that if they lose an arm or leg they are able to grow a new one. So therefore salamanders are used in the medical field by doctors to see if it is possible for people to regenerate limbs, too. The tiger salamander is the most common species of salamander, but there are three others that have been found in Iowa. They are the blue-spotted salamander, mudpuppy, and the central newt. Setting your eyes on these other three species is considered a considerable rarity.
The tiger salamander is a neat animal and very calm, so on your travels keep your eyes open for a slow traveler trying to making it across roads throughout the county.