Lena Collins

Invasive Species and Native Australian Clams

Lena Collins

Using funds from the International Research Opportunities Program (IROP), ecology, evolution and behavior student Lena Collins studied the effect ofÌýCaulerpa taxifoliaÌýon native clams in Wollongong, Australia.Ìý An invasive seaweed,ÌýCaulerpaÌýtaxifoliaÌýgrows everywhere from the surface of the ocean to the lower limits of underwater vegetation. Because this alga spreads by fragmentation and vegetative growth and is toxic to many grazers, it is nearly impossible to stopÌýCaulerpa’s spread. It now covers thousands of acres in the Mediterranean Sea, as well as being present in Australia and California.

To study the impact ofÌýCaulerpa taxifoliaÌýon the vulnerability ofÌýAnadara trapeziaÌýto predators and parasites, Lena performed research at St. George’s Basin, Australia. She placed 24 cages containing 10 clams each inside and outside ofÌýCaulerpa taxifoliaÌýbeds and assessed the clams’ mortality and health over a five-week period. She also collected clams from three different habitats—bare sediment, native seagrass, andÌýCaulerpa taxifoliaÌýbeds—and noticed distinct differences in parasite damage, the most occurring in theÌýCaulerpaÌýbeds.

Assistant Professor James Byers of the zoology department served as Lena’s UNH mentor, and she studied alongside University of Wollongong Professor Jeff Wright in Australia.