What is a common consequence of high water temperature in aquatic animals?

High water temperature can lead to several physiological and pathological changes in aquatic animals. One common consequence is the development of erythema or skin ulcers. Elevated temperatures can stress aquatic organisms, making them more susceptible to infections and diseases. Stress can result in compromised immune function, allowing pathogens to gain a foothold. The physical and metabolic effects of high temperatures can also cause cellular damage, leading to inflammation and skin lesions, which manifest as erythema or ulcers.

Increased feeding activity, improved respiratory function, and enhanced growth rates may occur at optimal temperatures, but these responses typically decline when temperatures rise beyond the comfortable physiological limits for the species. Prolonged exposure to high temperatures can actually diminish feeding due to stress and altered nutrient availability. Additionally, respiratory function can be compromised due to reduced oxygen solubility in warmer water, which also challenges the animals' ability to maintain normal physiological processes. Similarly, high temperatures can impair growth rates rather than enhance them, as the energy that would be used for growth may instead go toward coping with thermal stress.