During night dives, what effect does light have on marine life?

Light during night dives has a complex interaction with marine life that can result in either attraction or repulsion, depending on the species involved. Many marine organisms, particularly those that are prey species, may be drawn to artificial light sources because it can illuminate food sources or create a sense of safety in the presence of darkness. For example, plankton and smaller fish often congregate near lights, attracting larger predators, which can enhance the overall activity and abundance of marine life in the vicinity of the dive site.

Conversely, certain species may find light unsettling or threatening. Some fish and creatures prefer darker environments and may retreat or hide when exposed to bright lights. This behavior is often seen in nocturnal species that rely on the darkness for camouflage and safety.

Thus, it is crucial for divers to understand that while light can enhance visibility and reveal some aspects of the underwater world, it does not universally attract all marine life, nor does it maintain a consistent effect across different species. This understanding is vital for divers to interact with the underwater ecosystem responsibly and to anticipate how their use of light may influence the behavior of marine organisms during night dives.