School of Aquatic and Fishery Sciences

In a new documentary, Ocean Invaders, on NOVA PBS, join researchers from the UW School of Aquatic and Fishery Sciences (SAFS) as they uncover the hidden secrets of one of the world’s most invasive species: the lionfish.

Wreaking havoc on ocean reefs, one of the most popular ways of lionfish population control is spear fishing. However, lionfish have started to venture beyond the depth by which it’s possible to spear fish, presenting a new challenge.

In these deeper, darker depths, sometimes up to 1000ft below the surface, lionfish have been spotted, presenting a new threat to deep-reef native fishes.

Luke Tornabene, curator of fishes at the Burke Museum of Natural History and Culture and assistant professor at SAFS, has been undertaking research in the deep reef areas of Curacao for the last 10 years, with fellow marine biologist Carol Baldwin. Not only have they discovered over 30 new deep-reef species during this time, they’re also witnessing a growth in the lionfish population.

Before they even had a name for some of these new species, Luke shares that they have records of lionfish consuming them. So what extinction risk do lionfish pose? The answer is a big one.

Using a submarine, Luke and his team have been embarking on new research dives to collect as many lionfish as possible for the deep reef, during 8-hour descents. They then collect the fish, analyze their gut contents, and back in the lab on the University of Washington campus, they examine the contents.

Using extensive DNA analysis, they can reveal what fish fell prey to a lionfish, at what depth they live, and the time they were eaten.

This fascinating research provides insight into the great range of lionfish, who swim from the depths of the ocean to the surface in just a few hours, preying on native fish in both locations.

Whilst research continues into the movement, habitat and activity of lionfish, the presence of lionfish at the ocean’s surface means recreational divers, who are a key part of tackling the invasive species, can continue their work in the shallows.

Premiered on 26 October 2022, catch the full episode on NOVA PBS and find out more about the work of Luke Tornabene, the UW Fish Collection and SAFS researchers.