ACCESS Oceans

What can a scoop of seawater reveal?

eDNA stands for Environmental DNA, and is helping scientists move toward a future of non-fishing ocean sampling. Tiny traces left behind in the water — like skin cells, mucus, scales, and waste — can help identify what animals were recently in the area, even if they’re nowhere in sight.

The current state-of-the-art using eDNA, only tells us about presence or absence of wildlife in the water. We still need net sampling and visual observations to determine the numbers of each species in order to assess if species are trending upwards or downwards.

On this cruise, Hamali (NOAA Volunteer) and Maggie (Point Blue Intern) are processing water samples collected from the Niskin bottles on the CTD. The samples are run through special filters that capture microscopic particles, which will later be analyzed at MBARI for evidence of eDNA. Scientists then compare the results against known voucher species in a national database to help identify the organisms present in the ecosystem.

Every drop of seawater has a story to tell! What ocean animal would you hope to detect using eDNA? Let us know in the comments below.









📷 Flying Bridge view
of the CTD
Photo credit: NOAA/Point
Blue/ACCESS, K. DeForest

📷 Water samples for
eDNA taken from the CTD
Photo credit: NOAA/Point
Blue/ACCESS, R. Wallen

📷 Water samples being
processed in the wet lab
Photo credits: NOAA/Point
Blue/ACCESS, R. Pound

Science doesn’t sleep—and neither do the scientists aboard the R/V Shimada.
On the ACCESS Ocean expedition, teams work around the clock to understand life in the California Current. By day, they track seabirds and marine mammals while collecting ocean data and sampling the water column. By night, the work continues with specialized net tows that reveal what’s happening beneath the surface after dark.

Why does this matter? Because the ocean is constantly changing—and understanding those changes helps protect marine ecosystems, fisheries, and the health of our planet.

From sunrise to midnight, every sample and observation brings us closer to seeing the full picture, one Tucker trawl and CTD cast at a time









📷- Shimada crew deploy the CTD for nighttime sampling of water temperature and environmental DNA.
Photo credit: NOAA/Point Blue/ACCESS, L. Krigsman

📷 SFSU graduate student and nighttime science deck lead, Laila SanAhmadi, shows us her catch from the nighttime Tucker trawl. The cod end is overflowing with krill!
Photo credit: NOAA/Point Blue/ACCESS, L. Krigsman

📷 Graduate students, Amanda Nolen and Allie Johannsen, begin to process the phytoplankton samples. At the end of the cruise, these samples will be shipped to the state’s Department of Public Health Services to detect if there is the presence of diatoms that produce domoic acid poisoning or paralytic shellfish poisoning.
NOAA/Point Blue/ACCESS, J. Howar

📷 Observers from NOAA/Pt. Blue Conservation Science/Greater Farallones Association look for and count birds, mammals, and vessels for 10-12 hours per day.
Photo credit: NOAA/Point Blue/ACCESS, L. Krigsman

📷 Tucker Trawls happen day and night. Laila SanAhmadi and Lisa Krigsman will be up for a while, prepping that very full net!
Photo credit: NOAA/Point Blue/ACCESS, H. Jariwala

📷 A glimpse of krill and copepods that come out of a Tucker Trawl.
Photo credit: NOAA/Point Blue/ACCESS, L. Krigsman

📷 Ship side operations, Hoop net and CTD.
Photo credit: NOAA/Point Blue/ACCESS, J. Howar