We’re on the fourth day of an Applied California Current Ecosystem Studies, or ACCESS, cruise — a long-term effort, now in its 15th year, to monitor and understand the oceanographic conditions, prey availability, and abundance and distribution of seabirds and whales in the region. The data collected on these cruises, which take place three to five times per year, are used to help inform decision-making and research priorities in North-Central California National Marine Sanctuaries. ACCESS is a partnership between NOAA National Marine Sanctuaries and Point Blue Conservation Science.
On the flying bridge, the observers and data logger are bundled for what is shaping up to be the coldest and windiest day of the expedition so far. The radios many of us wear, click and buzz in unison, “Bridge to flying bridge, 15 minutes to the end of the line.”
“Copy that, thank you,” Data Logger Taylor Nairn replies.
Yesterday, the ocean merged into the sky at the horizon point with rich shades of blue, but today grey blends into grey. The quiet is peaceful.
Once we reach the end of this transect line, we will be “on station.” At set points along each transect line, there are five to six stations where the ship stops so a team can collect samples using a variety of equipment and techniques. As the wildlife observers’ work for the morning concludes, the wet lab team and deck crew spring into action.
Jamie Jahncke is the director of the California Current Group for Point Blue Conservation Science. He selected these points along the transect for sample collection. To Jahncke, the greater number of sampling locations allow his team to paint a more accurate portrait of what is happening where the warm, surface layer of water rests on top of the cold nutrient-rich layer.
He explains, when people look at water, everyone thinks it all looks the same, but it’s not. There are all these points where tiny differences in temperature will impact the distribution of food and prey. “We’re looking for places where critters tend to aggregate, attracting seabirds and whales,” says Jahncke.
Down on the side deck, the Conductivity, Temperature, Depth (CTD) rosette is deployed. The CTD carries 12 Niskin bottles with levers that allow the team to open them strategically, collecting water samples at various depths up to 500 meters. (A detailed explanation of this can be found here and here.)
According to Jahncke, measuring how well a water sample conducts electricity, also known as conductivity, is directly related to salinity. Salinity is the concentration of salt and other inorganic compounds in seawater. Salty seawater is heavier than freshwater, as is cold water. Combined with temperature data, scientists are able to better understand how water properties and nutrients are distributed throughout the water column.
While crew and wet lab team are out on the side deck, Grace Kumaishi is inside prepping labels and materials for the samples that will come in. There’s a great deal of labeling and packaging to do, so it is clear when and where the materials were gathered. Additionally, the findings will be shared with least 10 different federal, state, and non-government research institutions.
Kumaishi was really nervous for this, her first big cruise. She’s a research assistant at Point Blue. Having just completed her bachelor’s in ecology, behavior, and evolution at University of California Los Angeles, she’s in that nebulous period between undergraduate work and grad school. She’s debating the pros and cons of masters and Ph.D. programs. This internship with Point Blue offers her the opportunity to build relationships with mentors, watch graduate students conduct their research, and see firsthand what a career in ocean science might look like.
Most days for Kumaishi are spent in the lab processing samples collected on cruises such as this one. “It’s really nice to get out of the lab and do some field work,” she says.
Outside, the CTD is back on the deck and Carina Fish collects her samples first. Fish is doctoral candidate in marine biogeochemistry at University of California Davis’s Bodega Marine Laboratory. Using a small tube from the bottom of the bottle on the rosette, she rinses out a small brown glass bottle with seawater to make sure there are no contaminants. Then, she gives it a good shake, dumps the contents, and collects her sample. When Fish finishes she calls out, “Ryan, you ready?” He is there in a flash, using same process as Fish.
Ryan Anderson is working on a master’s in marine science with an emphasis on physical and chemical oceanography at San Francisco State University. The samples he gathers will be sent to a San Francisco State University lab to determine the amount of nutrients in the water.
Once Fish fills all her bottles, she adds mercuric chloride to each one; the chemical halts growth of any biological materials in the water without interacting with the carbonate chemistry that interests her.
Yesterday, Fish and I were up on the bow looking at a massive bloom of Chrysaora, or sea nettles. I asked her about the jellies; laughing loudly, she joked that she doesn’t know anything about “the living stuff.” Fish studies aragonite saturation states, which are used to track ocean acidification, a condition caused by climate change.
There’s a constant hum from the winch overhead and the deck vibrates beneath our feet. Everyone is wearing brightly colored foul weather gear, life jackets, and hard hats. On the side deck, we’re only about 12 feet above the water with heavy machinery and the ever-present threat of rough seas — safety is key.
After the CTD is pulled in, the hoop net is carefully lowered over the side. Ship speed and the amount of cable released impact the success of this process, so there’s a great deal of coordination between the bridge, the winch operator, the deck crew, and the wet lab team. If the cable is not at the correct angle, the net will drag at a depth that doesn’t pull in the zooplankton.
Once retrieved, Point Blue Senior Scientist and Program Biologist for ACCESS Meredith Elliott and Kumaishi rinse the hoop net to direct everything captured down into a container at the bottom of the net called a cod end. The contents are dumped into a sieve and filtered. Elliott carefully rinses everything several times to make sure she gets all the biological samples.
The nets are used to measure the quantity and variety of food sources available for the wildlife being observed and counted on the flying bridge. This process will be repeated at each station on the transects completed every day.
People mill; everyone has to wait for the moment when it’s time to perform their individual part in the production. Since timing is of the essence, no one leaves until the deck ops are complete, in spite of the aroma of pulled pork and warm spices wafting from mess.
It is time for lunch, but not until the work is done.
Jenny Woodman, Proteus founder and executive director, is a science writer and educator living in the Pacific Northwest. Follower her on Twitter @JennyWoodman.
Read more
Climate Change and Ocean Acidification by Cordell Bank National Marine Sanctuary
Searching for Answers at Sea: 2016 West Coast Ocean Acidification Cruise by Jenny Woodman
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