Dr. K (aka Dr. Jason Krumholz) is on the NOAA ship Henry B. Bigelow this week (the week of Nov. 17, 2013). The ship is part of NOAA’s National Marine Fisheries Service. He wasasked a question by LISS Communications Coordinator Robert Burg.
I’m at sea participating in a scientific research cruise on the NOAA fisheries vessel Henry B. Bigelow. This cruise is part of the National Marine Fisheries’ annual Fall Bottom Trawl, which establishes fisheries independent survey data for finfish and shellfish stock assessments. The Bigelow is packed with technological advancements that allow us to process the catch better, faster, safer, and more comfortably. When the net comes overboard, it’s dumped into a large checker, where a member of the scientific party loads the catch onto a conveyor belt which brings it into the main wet lab. Inside this heated lab (rather than out on deck, which can be uncomfortable and hazardous, particularly in Maine in the late fall and winter), a team of six scientists sorts the catch into buckets and baskets by species and size. Each bucket has a unique barcode on it. The catch is weighed and species ID’s are confirmed by the watch chief.
Once the sorting is done, the scientists move to processing stations, where a pair of scientists work up the catch, measuring and weighing each fish, distinguishing the sex of each fish, determining the age, and doing stomach samples for diet composition for a subsample of each species (otherwise it would take too long). This process is aided by a computer system linked to a magnetic weighing board (the person measuring the fish places a magnet on the board at the appropriate point and the computer automatically records the length), and digital scales, which eliminate handwriting of data collection. The computer system also prints up individual barcoded tags for collection of organ/tissue samples, otoliths (fish ear bones used for ageing), and food habits samples. This improves accuracy and speeds the process greatly, allowing us to get more data on more fish.
The system also allows researchers throughout the NOAA system to request specific fish species, organ/tissue samples, etc… for their own personal research. If a requested species crosses the board, the computer automatically alerts the scientists, and prints a barcoded tag that can be used to track and identify the sample date, time, and collection location, and link to oceanographic data (such as temperature, salinity and oxygen) which are also collected for that station.
I’ll be at sea for the remainder of this week. If you have any other questions about life at sea, the Bigelow, or the Trawl Survey, please feel free to send them in, and I’ll try to answer them as soon as I can!
Jason Krumholz, aka Dr., K, is the NOAA liaison to EPA’s Long Island Sound Office. Dr. Krumholz received his doctorate in oceanography at the University of Rhode Island Graduate School of Oceanography.
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Send an e-mail to Jason Krumholz.. Dr. Krumholz is a marine scientist working as the NOAA liaison to the EPA Long Island Sound Office. View more of Dr. K’s questions and answers on the Ask Dr. K blog.
Editor’s Note: The opinions expressed in this blog are those of the author. They do not reflect EPA or NOAA policy, endorsement, or action, and EPA or NOAA do not verify the accuracy or science of the contents of the blog.