Long-term UVB exposure promotes predator-inspection behaviour in a fish

Area of Science:

• Environmental Science
• Ecotoxicology
• Behavioral Ecology

Background:

• Stratospheric ozone depletion has increased surface ultraviolet-B (UVB) radiation.
• While UVB's cellular effects on aquatic life are known, its impact on behavior, especially predator-prey dynamics, over long periods and multiple life stages is understudied.

Purpose of the Study:

• To investigate the long-term behavioral consequences of ecologically relevant UVB exposure in aquatic organisms.
• To assess the effects of enhanced UVB on predator-prey interactions and body size in three-spined sticklebacks.

Main Methods:

• Three-spined sticklebacks (Gasterosteus aculeatus) were exposed to enhanced UVB levels under natural sunlight for seven months.
• A control group of full siblings was exposed to natural sunlight only.
• Predator inspection behavior and body length were measured and compared between groups.

Main Results:

• UVB-exposed sticklebacks exhibited increased predator-inspection behavior compared to controls.
• UVB-exposed sticklebacks had a smaller average body length than the control group.
• These behavioral and physical changes occurred after long-term exposure to enhanced UVB.

Conclusions:

• UVB radiation acts as a significant environmental stressor, influencing aquatic organism behavior.
• Altered antipredator behavior and reduced body size in sticklebacks suggest UVB impacts crucial ecological processes like predator-prey interactions.
• UVB-induced oxidative stress during development or size-related foraging strategies may explain the observed behavioral changes.