Getting up close and personal with salmon fry:
Understanding estuaries and
their role in salmon habitat
Ken Urstad and I showed up at the NOAA research facility near the University of Washington not knowing exactly what to expect of the invitation to join NOAA and the estuary team for our first "cutting party".
Anna Kagley of NOAA and one of the lead staff members on the Beach Watcher estuary project met and escorted us to a small lab/office area where three other NOAA members were already busy dissecting young Coho salmon fry captured during prior seining exercises. It was soon evident that Anna was in charge. The atmosphere of the cozy little room was intense and focused, yet casual and friendly. Ken and I dived in. After several hours of concentrated effort, we began to feel as if we were on the road to becoming Coho fry I.D. experts.
Our investigative efforts for the day included the dissection of salmon samples from 2002 and 2003. It was an assembly line operation. Anna had the master list and samples, Ken and I (under Anna's supervision) identified the fish and checked each one for an adipose fin (a missing adipose fin indicates the fish came from a hatchery). Hatchery fish may also be implanted with metal chips, easily detected by a metal detector shaped like a wand.
Once specimens are species identified, they are measured and weighed. Ken and I were eager to learn more! This was great stuff-much of what the seining team does out in the field, except for the dissection.
The next step in processing the fish began with the NOAA crew taking scale samples from each fry to determine its age and the length of time it was exposed to fresh water. The stomachs were removed, examined for content, and bagged. Then the Otolith, or bony, ear-like structure which helps balance the fish was removed. The Otolith is extremely small. It can also help to determine the age of the fish, as rings do on a tree core sample. Finally, a tail fin sample was taken for DNA testing. DNA in salmon can help identify the river system in which it hatched.
All of the parts are bagged separately and sent to different places for analysis. The information compiled becomes part of a huge juvenile salmon activity database. The Beach Watcher seining samples compliment the pocket estuary picture for Whidbey basin.
Our day at the "cutting party" was fascinating and well organized. It provided information critical to salmon research. Ken and I behaved quite well and may be invited back for a Chinook party-the hook being, we have to provide the entertainment. Stay tuned for more.
Bob Buck, Class of 2004For more information about this project read
Understanding estuaries and their role in salmon habitat.