Vishnu (he/him) is a fourth year Marine Biology major from Dana Point, CA with a special interest in conservation research and policy of the California coast. He is working in the Kroker lab to examine sea urchin diseases.

See the abstract to my talk for the 2022 Fall Undergraduate Research Symposium

Epidemics in the sea urchin Strongylocentrotus purpuratus have the potential to shift coastal ecosystems from barrens back to kelp forests. However, little is known about black spot disease in S.purpuratus; prior research, using artificial transfer of lesion tissue from one urchin to another, may not provide the best model of how urchins are infected in the wild. We applied various stressors to the urchins to determine if they affect the spread of black spot. We tested abrasions, spine-cutting, and healthy urchins by holding them in tanks of 18 total individuals, each with at least one corresponding tank with one black spot urchin out of the total. The tanks were monitored to see if there would be growth of current abrasions or development of new ones. Lesion size increased among urchins with abrasions that had been exposed to a black spot urchin and decreased in the abrasion only tank. In addition, seven of the abrasion and black spot exposed urchins died. We did not observe any significant results from other treatments. These results will allow us to better understand the effects of specific environmental stressors on mortality and in turn, can provide more insight into how disease dynamics can shape kelp forest habitats.