|
Department of Natural Resources
Introduction
| Agency
Resources |Anatomy
|Bibliography
| Conservation
| Defense | Salamander
Facts | Species
List | Gallery
| Glossary |
No photographs included
within this information may be used on the internet, publications, or
any other form of media without the photographer's express permission.
All rights reserved.
Life
History
Egg
masses of the spotted salamander (Ambystoma maculatum) attached
to an underwater twig. Developing eggs are surrounded by individual envelopes
and enclosed in a mass of firm, jellylike material.
Most Illinois
salamander species have a two-part life cycle that includes the gilled,
aquatic larval
stage and the terrestrial
adult stage. Therefore, they have access to two habitats at different
times in their lives. However, the adult mudpuppy (Necturus maculosus)
and lesser siren (Siren intermedia) spend their entire lives in
lakes, ponds, permanent streams, or swamps and never transform.
Embryos of the terrestrial redback salamander (Plethodon cinereus),
zigzag salamander (Plethodon dorsalis), and northern slimy salamander
(Plethodon glutinosus) undergo direct
development and have no larval stage. Rather, their eggs
develop directly into tiny versions of the adults.
Courtship
and egg-laying are annual events. Males and females of all but the hellbender
(Cryptobranchus alleganiensis) engage in a distinctive courtship
behavior during which sperm from spermatophores
deposited by males are transferred to the cloaca
of females. The sperm fertilize the eggs just before they are released to
the environment. Females of most species lay their eggs in the spring, while
the remainder deposit eggs in autumn. The eggs are placed in a variety of
wet or moist places, such as: woodland ponds; under rocks in streams; under
mosses, logs, rocks, or leaves along streams or ponds; inside rotting logs;
in underground burrows; in rock crevices; or in caves. In some species,
adults care for the developing embryos. The adult may stay with the eggs
to keep them moist (if on land) by curling its body around them, protect
them from predators, and remove dead and decomposing eggs. In other species,
the jellylike egg masses are attached to plant stems and twigs in fish-free
pools and left with no parental care. Development from embryo into larval
form takes from two weeks to three months, depending on the species.
The eastern newt (Notophthalmus viridescens) is peculiar because
it goes through three distinct stages during its life: larva,
eft, and adult. Adult newts live in lakes and ponds, where
the female lays numerous tiny eggs wrapped individually in leaves of underwater
plants. The embryo completes development in about two weeks and hatches
into an aquatic larva that feeds and grows for a few months, then transforms
into the eft. This juvenile
newt lives on land for one to three years before returning to water to complete
its transformation to the adult form.
Adult and juvenile mole salamanders (family Ambystomatidae) live in rotting
logs and burrow in the forest floor. They emerge at night or during heavy
rain to feed, and, in spring and autumn, to migrate to breeding ponds. The
terrestrial and streamside lungless salamanders (family Plethodontidae)
are seldom active on the surface of the ground except at night, usually
following rain. Because of their
respiratory skins that can dry out quickly, these animals
live under moist leaves, logs, and rocks, or in burrows. Juveniles and adults
of some species are common around springs (cave salamander, Eurycea lucifuga;
four-toed salamander, Hemidactylium scutatum; longtail salamander,
Eurycea longicauda), banks of small, rocky streams (dusky salamander,
Desmognathus fuscus; southern two-lined salamander, Eurycea cirrigera;
longtail salamander, Eurycea longicauda), and in forest floor litter
(redback salamander Plethodon cinereus; zigzag salamander, Plethodon
dorsalis; northern slimy salamander, Plethodon glutinosus). Many
lungless salamanders seem to be territorial, with home ranges that they
defend by posturing, chasing, and biting other salamanders.
Return
to || Reptiles & Amphibians
|| Wild About Animals
|| Stuff for Teachers &
Students ||
|
