Salamanders are amphibians characterized by slender bodies, short limbs, and tails. While they do swim, their aquatic abilities are highly variable across species. Proficiency depends entirely on the life stage and whether the species is adapted for a fully aquatic, semi-aquatic, or largely terrestrial existence.
Mechanics of Salamander Swimming
Salamanders primarily move through water using an undulatory motion of their trunk and tail. This propulsion method is known as anguilliform locomotion, similar to that of eels. A traveling wave of lateral flexion moves down the body axis, pushing water backward to propel the animal forward. The wave’s amplitude increases significantly toward the tip of the tail, where the greatest force is generated.
This swimming style relies heavily on the powerful epaxial muscles along the spine. These muscles contract sequentially on alternating sides of the body to create the characteristic S-shaped curve. The limbs play a minor role in propulsion. The four short limbs are often tucked against the body to reduce drag and maintain a streamlined shape, and are mainly used for minor steering adjustments or for slow movement along the substrate.
Aquatic Stages of the Salamander Life Cycle
All salamanders begin their lives in the water. Eggs hatch into aquatic larvae, which possess external gills and a prominent tail fin. During this larval stage, they are entirely dependent on the aquatic environment for survival and are proficient swimmers.
As the larvae mature, they undergo metamorphosis, losing their external gills and tail fin, while developing lungs for air breathing. Most adult salamanders, even terrestrial ones, must return to water for breeding purposes. This necessitates a temporary but functional swimming ability to navigate to breeding pools, court mates, and deposit eggs.
Habitat Determines Swimming Frequency
The frequency and skill of adult salamander swimming is determined by whether the species is fully aquatic, semi-aquatic, or terrestrial. Fully aquatic species, such as Mudpuppies or Sirens, spend their entire lives submerged and are excellent swimmers. These animals often retain larval features like external gills (neoteny) and are highly adapted for continuous life in water.
Terrestrial salamanders, like the Mole Salamanders (Ambystoma genus), are poor swimmers and only enter water briefly during the breeding season. Newts, which are a specific type of salamander, represent a transitional lifestyle. They spend a portion of the year on land but return to water to breed, exhibiting a seasonal shift in their aquatic activity.