CONFIRMING SEAL PRESENCE BY ANALYZING ENVIRONMENTAL DNA (eDNA) & RNA (eRNA)

 Identification of the aquatic mammal species in environments has been challenging due to constraints with traditional surveys. Moreover, human impact on marine mammals is still unknown. With offshore wind farm development throughout the East Coast, there are potential impacts on marine mammals. Environmental DNA (eDNA) and RNA (eRNA) have successfully been utilized to investigate species’ presence. This research focused on the development and application of eDNA /eRNA detection on gray seals (Halichoerus grypus). The research questions were: 1) Can we identify gray seal DNA/RNA within aquatic environments? 2) How long do the DNA/RNA signals persist within aquatic environments? Water samples were collected from the Animal Rescue Clinic of Mystic Aquarium when the seals were present (Pre) after the seals were removed for release (Post) and during the release back to the ocean (Field). Following filtering, DNA and RNA were extracted simultaneously, and real-time PCR (qPCR) quantification of a mitochondrial control region was performed. The results showed the mean RNA yield (4796ng) and DNA yield (1094ng). qPCR results on eDNA suggest that gray seal species can be observed for up to 11 days and up to 1 day using eRNA following removal. Moreover, the seal eDNA concentrations showed a linear decrease over time (R2 = 0.9595). Preliminary results suggest the possibility of detecting gray seal presence in aquatic environments by examining water. Further validation can potentially be utilized to help determine changes in the distribution of endangered marine mammals due to stressors.

Presentation Preference: Oral

Primary Presenter: Gavin Pirtle, UC Davis (Gavinatwork1@Gmail.com)

Authors:

Gavin Pirtle, UC Davis/Los Medanos Community College  (Gavinatwork1@Gmail.com)

Ebru Unal, University of Connecticut/Mystic Aquarium  (eunal@mysticaquarium.org)

Tracy Romano, University of Connecticut/Mystic Aquarium  (tromano@mysticaquarium.org)