Axolotls are unique aquatic salamanders that remain fully aquatic throughout their lives, a characteristic known as neoteny. Unlike most other salamander species, they do not transition to land as adults. Their ability to breathe air is often misunderstood, making it important to understand their respiratory needs for proper care and health.
Aquatic Respiration
Axolotls primarily breathe underwater through their prominent external gills. These feathery structures, located behind their heads, are rich in blood vessels and increase the surface area for gas exchange. As water flows over the gill filaments, oxygen diffuses into the bloodstream, while carbon dioxide is released. Axolotls can wave their gills to enhance water flow and improve oxygen absorption, especially in less oxygenated conditions.
Axolotls also absorb oxygen through their thin, permeable skin, a process called cutaneous respiration. This method is supplementary but becomes more significant in well-oxygenated water, where capillaries close to the skin’s surface facilitate gas diffusion. Their skin remains moist underwater, which is crucial for this type of respiration, demonstrating their adaptation for a life submerged.
When Axolotls Surface for Air
While axolotls are primarily aquatic breathers, they possess rudimentary lungs and can surface to gulp air. This behavior is not healthy and typically signals an issue with their environment. Frequent air gulping often indicates stress, commonly due to poor water quality or insufficient dissolved oxygen levels in the tank.
Low oxygen levels in the water, which can result from high temperatures or inadequate aeration, force the axolotl to seek oxygen from the surface as an emergency response. High concentrations of toxic compounds like ammonia, nitrites, or elevated nitrates can also damage their gills, making it difficult to absorb enough oxygen. Surfacing for air then becomes a compensatory mechanism, indicating a need for immediate attention to their living conditions. Other signs of stress alongside frequent surfacing can include lethargy, loss of appetite, curled forward gills, or a curled tail tip.
Creating a Healthy Aquatic Environment
Maintaining a healthy aquatic environment is important for preventing axolotls from needing to surface for air due to distress. Water temperature is particularly important; axolotls thrive in cooler conditions, ideally between 16-18°C (60-64°F). Temperatures exceeding 20°C (68°F) can cause stress and reduce the water’s ability to hold dissolved oxygen.
Water parameters must be consistently monitored to ensure optimal conditions. Ammonia and nitrite levels should always be at zero parts per million (ppm), as these compounds are highly toxic to axolotls. Nitrate levels should be kept below 20 ppm, with an ideal range of 5-20 ppm. The pH of the water should be maintained between 6.5 and 8.0, with an ideal range of 7.0-7.5.
Proper filtration is important for removing waste and establishing beneficial bacteria that process harmful nitrogenous compounds. Regular partial water changes, typically 20-30% weekly, are also necessary to dilute nitrates and maintain overall water quality, ensuring a stress-free habitat with ample dissolved oxygen.