Seminar – John LaRiverie

John LaRivierie | Scoot Science
Presenting: "Oceanographers building an ocean risk business for aquaculture and beyond"
Hosted by the Executive Director, Petra Dekens

MLML Seminar | April 10th, 2024 at noon

Watch the Live Stream here or here

Abstract:

The modern fish farmer must weigh many, often conflicting, factors when making operational decisions on a farm site. They're balancing sales needs, resource limitations, and complex animal husbandry issues with a constantly changing set of ocean conditions on each farm. Technology is transforming this challenge through an ever-expanding IoT dataset (e.g., high resolution hydrographic sensors) and new tools like automated lice counting. In this talk we’ll look at how a group of oceanographers built software tools to translate the raw ocean observations into data-driven actions and behaviors to improve fish health and welfare on the farm sites. We’ll look at the ways ocean data analysis add confidence to feeding, treatment, and mitigation decisions as well as the process of founding the business.

Bio:

Jonathan LaRiviere is Chief Executive of Scoot Science, an ocean analytics and forecasting business based in Santa Cruz, California, which aims to help fish farmers protect assets, operate sustainably, and increase profits by enabling a more complete assessment of local ocean conditions. Scoot’s platform integrates in-pen sensors with external data sources to provide real-time information and forecasting for conditions in the marine environment. Jonathan co-founded Scoot in 2017 and was previously a lecturer at Santa Clara University. His research on reconstructing past ocean temperatures, CO2 levels and climate conditions to understand how the oceans and earth systems respond to climate change has been published in Nature, Nature Geoscience, Science, and Geophysical Research Letters. He holds a PhD in Ocean Sciences from UCSC.

 

Seminar – Matt McCarthy

Matt McCarthy | UC Santa Cruz
Presenting: "Individual Amino Acid Stable Isotope analysis in Ecology and Paleoecology: new tools for understanding primary production, food web connectivity, animal migration, symbioses and beyond."
Hosted by the Executive Director, Petra Dekens

MLML Seminar | April 10th, 2024 at noon

Watch the Live Stream here or here

Abstract:

In the past two decades compound-specific isotope analysis of amino acids (CSI-AA) has exploded, moving from a novel analysis performed by a few labs to an increasingly mainstream technique, employed across a steadily increasing range of disciplines from ecology, archaeology, paleoceanography, geomicrobiology, and biogeochemical cycle research. Amino acid stable carbon (13CAA) and nitrogen (15NAA) measurements remain the best developed applications, with D/H ratios of AA  and molecular position-specific isotopes representing the next frontier. Most work to date has focused on establishing trophic connectivity and baseline isotope values in modern and palaeoecological applications. This talk will present an overview CSI-AA techniques and potential applications, focused primarily on coupling 15NAA and 13CAA potential to establish trophic connectivity, primary production and nutrient sources at the base of food webs, and applications coupling CSI-AA with isoscape to understand animal migration or shifts in feeding zones.  Finally, it will focus on new potential and emerging applications, such as exploring symbioses in extant organisms as well as microfossils.

Bio:

Mathew McCarthy is a marine organic geochemist and  Professor of Oceanography at University of California Santa Cruz.   A chemist by training, he studied bio- and organic chemistry at UC San Diego Rodger Revelle college, followed by two years working as a chemist on  Methyl Mercury contamination in the Mediterranean at the International Atomic Agency - Marine Environmental Studies Laboratory in Monaco.  Returning to the US, he received his PhD from University of Washington in Oceanography and Organic Geochemistry in 1998, working with John Hedges on new approaches to understand structures and bioavailability of marine dissolved organic matter.  After his PhD he received a Chateaubriand Fellowship to study in Paris, was then a Carnegie postdoctoral fellow at the Carnegie Geophysical lab in Washington DC,  and finally received a University of Hawaii young investigator award to work on interactions between microbial loop processes and DOM production, before coming to UC Santa Cruz as an assistant professor in 2001.

The McCarthy Lab focuses on developing and applying organic and stable isotope methods to address a wide range of biogeochemical, paleo-oceanographic and ocean ecology questions.   A main focus has been developing compound-specific amino acid isotope techniques and approaches

Thesis Defense by Logan Grady – March 25th

"Observations of Currents, Waves, and Turbulence within a Giant Kelp Forest in Stillwater Cove, Carmel, California"
A Thesis Defense by Logan Grady

Physical Oceanography Lab

Live-Stream | March 25th, 2024 at 12:00 pm PDT

Logan Grady at the helm of MLML's Navy Whaler in Stillwater Cove. Photograph taken by Roxanne Garibay.

Abstract

Giant kelp (Macrocystis pyrifera) forests are hydrodynamically complex regions of enhanced drag that rely on turbulence for nutrient distribution and propagule dispersal. Currently, there are no in-situ measurements of turbulence within giant kelp forests and studies of driving mechanisms for turbulence are limited to controlled flume experiments. This study investigates relationships between currents, surface gravity waves, and turbulence within a kelp forest through deployment of moored instrumentation and kelp surveys in Stillwater Cove, California from July 22 to August 30, 2022. Oceanographic conditions during this time period are primarily driven by coastal upwelling and semi-diurnal internal tides, which likely originate from the Carmel Submarine Canyon. During rising tides, these internal waves are associated with cooling events and enhanced onshore velocity within the kelp forest. Estimates of gradient Richardson numbers and kelp Reynolds numbers indicate that cooling events are likely not associated with shear instabilities in the bottom layer, while enhanced bottom velocities could consistently generate turbulent kelp wake. Turbulent kinetic energy dissipation rate (ε) was calculated using data from an acoustic Doppler velocimeter, spanning a range of 1.9 x 10 -8 to 8.0 x 10 -7 m 2 /s 3 . Onshore velocities associated with cooling events are positively correlated with ε, while offshore velocities are not. This asymmetrical pattern implies a directional relationship triggered by cooling events, which may generate turbulence through interactions with dense kelp and rough bottom substrate. Models of submerged vegetation wake production and bottom boundary layer production of turbulent kinetic energy are compared to observed values of ε to assess hypothetical kelp and bed drag coefficients.

 

Bio

Logan graduated from the University of California Santa Cruz in 2020 with a B.S. in Environmental Science and a passion for scientific SCUBA diving in Monterey Bay. With an interest in ocean physics and the native kelp forests, he went on to attend Moss Landing Marine Laboratories under the advisorship of Dr. Tom Connolly. His current project investigates how nearshore currents, waves, and turbulence are influenced by giant kelp forests. In his free time, Logan can be found mountain biking, watching Formula 1, or at various trivia nights around Santa Cruz.

Diver Logan Grady prepares to measure the dimensions of an acoustic Doppler velocimeter deployed at his study site in Stillwater Cove. Photograph taken by Bennett Bugbee.

Picture of Stillwater Cove mouth from the kelp forest mooring location, looking out at the Pescadero Rocks and Pescadero Point. Photograph taken by Roxanne Garibay.