A rare photosynthesizing sea slug, Elysia chlorotica, was found off Rainbow Haven Provincial Park in Nova Scotia by snorkeler Elli Ofthenorth, sparking excitement among scientists.

The Nova Scotia discovery has drawn renewed interest from researchers on both the East and West Coasts of the U.S., with efforts to collect specimens for lab study and expand field surveys.

E. chlorotica can photosynthesize by stealing chloroplasts from algae it eats, allowing the slug to derive energy from sunlight and potentially survive for months without feeding.

Researchers regard E. chlorotica as a top photosynthesizing sea slug due to its exceptional retention of chloroplasts, though the exact duration remains uncertain.

Potential research applications span wound repair, energy technologies, drug therapies, vaccines, and inflammatory, neurodegenerative, and age-related disease research by leveraging chloroplast incorporation and maintenance.

Population dynamics are elusive and episodic, with historical sightings in Nova Scotia’s Minas Basin and Massachusetts’s Martha’s Vineyard, and possible presence along the Eastern Seaboard, but recent sightings are sporadic.

Scientists and citizen scientists are increasingly collaborating to locate and study these slugs, underscoring the value of protected areas and public engagement in biodiversity discovery.

The slug's habitat requires tidal pools with mild currents, a mix of salty and fresh water, access to sunlight, and specific food sources; pollution and shifting currents threaten populations and complicate lab maintenance.