Friday, July 26, 2013

Ella- WEEK FIVE: festivitals, clamming, parasites and boats

A racing "kinetic sculpture"
This super busy week five started out with Da Vinci days, a festival celebrating science and art in Corvallis, Oregon. One of the main features were the kinetic sculpture races. Over the course of the weekend, these people powered sculptures raced through town, over sand dunes and down the Willamette river. All of the vehicles had to have their flotation gear on board the entire time, and the time it took to transfigure the sculpture into a boat was counted as part of the race. Although I somehow missed the start and end of all three different races, I still got to see them lining the streets, in all their creativity, waiting to disembark on the next race.
OSU slocum glider

Inside the festival, there were many booths with educational displays from organizations around Oregon and also many booths from different departments at OSU. One of the booths was representing the glider to the right. This device is used to measure oceanic conditions, recording data such as temperature, salinity and dissolved oxygen levels, which is used in understanding upwelling and hypoxia. The great thing about the glider is that it is self propelled, using something similar to a swim bladder, taking on and off sea water as needed to propel itself in a porpoise-like way along transects off the Oregon coast. This is extremely useful as the glider can amass a great deal of data and periodically sends all its information on via satellite, all on its own! Here is the link to the OSU's glider wepage:

Back at Hatfield, all of the interns had the opportunity to tour NOAA's  R/V Bill M. Shamata and The University of Washington's R/V Thomas G. Thompson, both of which were docked in Newport for a few days.

Scale and fish ruler talk to computer:
this setup makes weighing and measuring
large amounts of fish on the Shamata super efficient!
The Bell M. Shamata does fish surveys from
California to British Colombia. Currently,
they are specifically monitoring Hake and anchovies. 
R/V Thompson with ROPOS ready to decend. ROPOS: Remotely Operated Platform for Ocean Sciences.  Image from'12+Cancelled

On the Thompson: this sophisticated machine is used to
survey Ocean floors up to 5000 meters deep! It is equipped with lights and cameras as well as remote controlled "hands".

Source: Trematodes of North America by Stewart C. Schell. 
Lettuce, snails and parasites
 (not visible with the naked eye)
Next on the itinerary was a snailing adventure on the Selitz river, collecting fresh water snails for a fellow intern's REU project with Kim Jacobson's parasitology lab. As many of the beam trawls in our data set have come from the mouth of the Selitz river, it was neat to be able to do some data collection in this river, and the weather was beautifully perfect as well! The objective of the trip was to collect some hundred of these freshwater snails in order to identify the various trematodes living inside of them. Back at the lab, we could see that most of them did have at least one type of trematode, as they came out of the shells over night and wriggled around in the Petri dish in cercaria form (see diagram above). If the snails had still been in the river, these trematodes would then have found a salmon to latch on to or be eaten by (depending on which species of trematode they were). In the salmon they would live and thrive in the posterior kidney until the fish got eaten by a some bird or mammal, such as a dog. At this point, a harmful bacteria which would have been living on the trematode the entire time would cause the dog to be very sick, also known as "salmon poisoning". This is why it is never a good idea to let your puppy eat raw salmon!
A cercaria medusa found in one of the Petri dishes.
The individual cercaria prefer forming this mass, as being bigger attracts hungry fish better, a major goal at this stage in the lifecycle of the trematode.You can't tell here, but the ends of all the "arms" are wiggling
about frantically, quite the sight  when seen under the microscope! 

Speaking of smaller organisms living within larger ones, this is a Pea Crab found within a gaper clam destined for dinner last night.
The tragic end to a commensal relationship
While researching these little crabs, I came across this COSEE blog entry from 2010:
Check it out the link! It is a very concise and helpful description of the little guys.
My very first fishing licence: watch out shellfish!
The amazing neck of a Gaper clam found in
the mudflats of our front yard
Crying cockles and muscles alive alive oh!

A beautiful and tasty way to end the week.
I am so grateful to have been able to experience
 wild harvesting the bounty of Oregon's coast.
This week was a landmark in our data entry project as I finished the first binder of beam trawls from 1978! Next week is NOAA's fish cutting party: where lots of scientists get together to dissect salmon and each take home a part to study for their respective projects. This is an event all interns are strongly encouraged to attend, and it will be interesting to see the salmon kidneys full of the next life cycle of trematodes.

No comments:

Post a Comment