Projects
Experimental Validation and Development of an eDNA Fate and Transport Model
Research Questions
(1) How do molecular detections vary in space and time, given a known point source? (2) Can we model the fate and transport of eDNA molecules for a target species and estimate the time since deposition? (3) Can we hindcast the most probable time and place for a point source, give quantitative eDNA detections?
Geographic Scope
Naval Base Kitsap in Bangor, WA and greater Hood Canal, WA; surface and mid-depth (25-50 m) water samples.
Description
eDNA models generated from experimental mesocosms are unlikely to directly estimate the fate and transport of eDNA particles under real-world scenarios. Leveraging existing oceanographic models from a well-characterized marine system in the Pacific Northwest and marine-mammal assets at the Naval Base Kitsap in Bangor, WA we will quantify eDNA at multiple concurrent sampling locations and develop an in situ eDNA fate-and-transport model. Multiple sampling campaigns will provide several opportunities to quantify the genetic detection of eDNA signals using species-specific eDNA dynamics based on real-time eDNA sampling relative to the known movements, abundance, and occurrence of a non-native species (Atlantic bottlenose dolphin, Tursiops truncatus) in a marine ‘megacosm’ experiment.
Comparing Complementary Approaches for Detecting Cetaceans
Research Questions
(1) How are marine-mammal detections via eDNA distributed in time and space? (2) How can we best integrate eDNA detections with contemporaneous visual and passive acoustic observations? (3) Can we reconstruct historical cetacean and prey fields via archival molecular analysis?
Geographic Scope
Southern and Central California, variable depths up to 1000 m based on CTD casts at CalCOFI stations.
Description
Because many cetacean species surface infrequently and can be difficult to observe or determine species ID at the surface, and because passive acoustic methods capture only acoustically active cetaceans, molecular methods may substantially increase our ability to map marine mammals in the ocean. Here we propose using an integrated set of samples of the California Cooperative Oceanic Fisheries Investigations (CalCOFI) cruises across the Southern California Bight to systematically our eDNA probability-field framework and directly compare acoustic, visual, and genetic detection methods for cetaceans over a 17-year archival time-series spanning >500 eDNA samples. Integrating mammal observations from acoustic, visual, and genetic methods will both improve overall detection capabilities and will allow for comparison of the relative strengths and limitations of each individual data stream. The results of this project thus inform sampling efforts of other species and geographies by establishing a framework for integrating multiple datastreams and assessing the sensitivity and specificity of eDNA relative to existing traditional detection methods.
Large-Scale Coastal Survey
Research Questions
(1) What is the 2D distribution of eDNA from marine mammals along the US West Coast? (2) What prey/target species co-occur with marine mammals in the California Large Marine Ecosystem (LME)? (3) Are there consistent hotspots of marine mammal DNA and do they corroborate existing hotspot knowledge?
Geographic Scope
California, Oregon, Washington, British Columbia Coastal waters; surface, 50 m, 100 m, 150 m, and up to 500 m depth.
Description
This project leverages NOAA’s considerable investment in the Pacific Hake Acoustic-Trawl Survey, which surveys the coasts of California, Oregon, Washington, and British Columbia for a biennial, fisheries-independent survey of the Pacific hake (Merluccius productus) population. The hake survey is an opportunity to use the lessons of the entire MMARINeDNA project regarding the distribution and behavior of eDNA in space and time, applying those at the scale of the California Large Marine Ecosystem.
This project addresses the specific primary research questions using comprehensive sampling from a large, oceangoing vessel across multiple years, qPCR for key mammal species, metabarcoding for mammals and non-mammals to document prey or other co-occurring species over space and time. Resulting data are then fed into a statistical model that spatially smooths observations and relates eDNA detections to abundance estimates of target species in the field.
