Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Related Datasets
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

These data were published in Lyle, J.T. et al. Table II

Pyrosoma atlanticum colonies were collected from coupled Multiple Opening and Closing Environmental Sensing System (MOCNESS) tows (Guigand et al., 2005). The nets had openings of 1 m2 and 4 m2 with mesh sizes of 333 µm and 1000 µm, respectively. The pair of nets sampled to 100 m depth in four separate 25-m bins, and a fifth net (“net 0”) was towed to 100 m during the downcast. Pyrosome colonies in each net were enumerated and their volume measured by displacement. Biovolume (mL•m-3) was calculated by dividing the total pyrosome volume by the volume of water sampled in that tow. If pyrosomes were too numerous to count, a subset of 20 from each depth bin were measured for biovolume. Colony lengths were only measured during July 2018.

Multiple Opening/Closing Net and Environmental Sensing Systems (MOCNESS) fitted with a 4 m2 net with 1 mm mesh and a 1 m2 net with 333 µm mesh.

Pyrosome abundance and biovolume were processed in Excel (v.16.16.4). MOCNESS filtered volumes were sourced from this dataset: https://www.bco-dmo.org/dataset/783036

This project will examine the coastal ocean mesozooplankton community and their predation by early life stages of fish in the northern California Current. The goal is to understand how these predator-prey interactions change during different oceanographic regimes that vary seasonally in the region. This study will use a very high-resolution imaging system coupled with net samples to measure trophic interactions within the zooplankton community across a range of environmental parameters (e.g., temperature, relative timing and intensity of upwelling). The camera provides detailed information on the fine-scale abundance and spatial distributions of a wide diversity of plankton, while the net samples will provide biological samples for diet-related analyses. This project will train 12 undergraduate and two graduate students and one post-doctoral scholar. The research team will develop a variety of educational activities and products to facilitate greater outreach to public audiences. Plankton imagery from this project will be used to build the Global Plankton Imagery Library, an open-access repository for plankton imagery that will be a resource for the research community. The researchers will expand the imagery available in the Plankton Portal, a public website they developed in partnership with the Citizen Science Alliance's Zooniverse, that invites citizen scientists to participate in classifying plankton from field photographs. They will collaborate with Science Education specialists to include Plankton Portal kiosks in a new public exhibit at the Oregon State University's Hatfield Marine Science Center (HMSC) Visitor Center, which annually hosts 150,000 visitors of all ages. Importantly, this activity will not only educate K-12 and beyond, but will enable researchers to study what factors motivate citizen scientists, what characterizes "heavy-users", and how those users can be supported and encouraged into advanced collaborator roles. A multi-media artist will join the research cruises as part of the new Artist-At-Sea program. Their artwork will be displayed at the HMSC Visitor Center and University of Oregon's Charleston Marine Life Center and a scaled traveling show will tour Oregon metropolitan areas and underserved communities.

Eastern boundary currents are among the most productive marine ecosystems on the planet and support a significant proportion of global fisheries, yet there are unanswered questions about the role of non-crustacean zooplankton in transferring production through upwelling food webs. This study will answer key questions about the food web dynamics associated with mesozooplankton linkages, sources of carbon production, and consequences for upper trophic levels in different shelf upwelling systems. Not only is there a knowledge gap in how the food web currently functions in transition areas of major eastern boundary current systems, but there is increasing evidence that these systems are changing. Regional and global shifts in major currents, including upwelling strength, together with temperature-induced latitudinal shifts in species ranges that are already occurring and predicted to continue will have major effects on interactions among species, and consequently, food webs. Understanding these interactions and predicting future changes is highly relevant to science, society, and economies. The researchers plan to sample the winter and summer seasons in the northern California Current off central Oregon (intermittent upwelling) and northern California (continuous upwelling) with the high resolution In Situ Ichthyoplankton Imaging System to obtain an accurate description of mesozooplankton communities: their abundances, and horizontal and vertical spatial distributions, over contrasting upwelling/downwelling system dynamics. In parallel, they plan to collect depth-discrete mesozooplankton samples to quantify seasonal diets for larval fishes and gelatinous zooplankton and prey-specific growth rates of larval fishes. Stable isotope analysis of mesozooplankton predators and prey will reveal the relative role of new vs. regenerated production in sustaining food webs such major eastern boundary currents.