Front Row: L to R – Andres Valverde, Erika Lee, Luis Felipe Navarro, Ruben Castro, Eduardo Santamaria – Back Row: L to R – Maria Fernanda Gracia, Ashley Wheeler, Rene’ Navarro, Thomas Rago, Curtis A. Collins
As the Point Sur crew arrived in Mazatlan, Mexico a party was there to greet them. Not your typical party of spring breakers on vacation, but a scientific party, comprised of American, Colombian, and Mexican researchers from three different universities: Universidad Autónoma de Baja California, Naval Postgraduate School, and Moss Landing Marine Laboratories. Chief scientists, Dr. Ruben Castro (UABC) and Dr. Curtis Collins (NPS), brought their colleagues and students aboard and together with the Point Sur crew, embarked on a scientific expedition sampling the waters at the entrance of the Gulf of California and around the Baja Peninsula.
Map of Collins/Castro proposed stations. Blue dots indicate an across Gulf section in Pescadero Basin and red dots are stations along the Baja California coast that would be used to trace the flow of Gulf of California waters into the Pacific Ocean.
Surface waters in the mouth of the Gulf are highly productive, however subsurface waters contain very little oxygen, forcing biological organisms in these waters to use excess nitrogen to survive. As the Gulf and Pacific waters mix, these subsurface waters are transported by the California Undercurrent, possibly having adverse effects on fisheries in southern California due to the lack of oxygen.
Graphic depicting salinity levels in and around the Gulf of California as mixing occurs with the Pacific Ocean. The red, orange and yellow colors are a higher concentration of salinity and the purple, blue and green are lower.
To understand how these two water bodies interact, a CTD (Conductivity, Temperature, Depth) probe is being used to measure physical properties of the water column. As the CTD is lowered through the water column, real time data is relayed back to the ship’s computers and can be observed by the researchers. Niskin bottles are used to capture water samples at various depths.
Ready on deck, the CTD package is set to deploy at sunrise – Photo by Ashley Wheeler
The samples will be analyzed for nutrients, salt content, and biological productivity. Since leaving Mazatlan, a total of 65 CTD casts have been deployed and recovered, collecting over 400 water samples and we are still counting, working to complete 9 more casts on the way home!
Deploying the CTD – Photo by Tara Pastuszek
What is unique about this expedition is the camaraderie that has enveloped the Point Sur because of the international community aboard the ship. This project fosters the continued cooperative, international ocean studies that are necessary to understand joint management of common ocean resources. Although our heritage, nationality, and even our native languages differ, these factors do not inhibit our ability to relate and connect with one another. We all share a common goal – knowledge – Science unites us around the globe!
Ashley Wheeler – Photo by Tara Pastuszek
Blog post contributed by Ashley Wheeler, MLML graduate student – For her thesis, Ashley is completing a comparative study on the erosion of salt marshes in Elkhorn Slough. She volunteered to assist in this cruise to expand her fieldwork and increase her ship time experience….Thanks Ashley!