Sunday, August 25, 2013

Kaylynne - Catching Up!


I have been horrible with writing my weekly blog posts and I sincerely apologize. To make up for it, I will post bits and pieces of what I have been doing this summer. I have been working for Dr. Alan Shanks and the Shanks Lab graduate students, researching nearshore biological oceanography and larval recruitment. To be more specific, I have been working mostly for/with Marley Jarvis, who is a PhD candidate in the Shanks Lab. Marley's research is looking into the effects of nearshore fronts on the settlement of algae propagules and barnacle larvae, known as cyprids. She has taught me how to collect physical data for her research while she is on leave for over a month. It is pretty exciting that I was given this opportunity, trusted with her research and I feel pretty lucky to have gained experience that will benefit me greatly later on in my education.

This is Marley and she studies nearshore fronts and planktonic dispersal along the coast. However, her data currently being collected has yet to be analyzed and is part of an ongoing research project. 

This image shows a nearshore front which can be seen as a foam-line. A foam-line is only present during upwelling conditions.

How do these nearshore fronts form?

This is Sunset Bay, one of the sites under observation, and the yellow-green oval highlights a foam-line. The nearshore front is caused by the alongshore current interacting with the land’s topography, creating this foam-line. This nearshore front along the mouth of the bay is only present during phases of upwelling winds, which blow Southward from the North.

This is a red alga propagule. Propagules are good models for this research because once they are trapped in the bay by the front, they may have higher settlement rates.
Photo by: Zac Swider
Magnification: 40X dry lense, 1X trunk lense, 0.5X coupler
Marley has taught me how to collect physical data using the following oceanographic instruments:

CTD: Conductivity (salinity), Temperature and Depth. This device is lowered vertically into the ocean on both sides (inshore/offshore) of a foamline to gather data. This data can be used to form graphs which show distinct differences in salinity, temperature, chlorophyll content and backscatter. We call this a 'CTD Transect', because as the device is lowered it takes measurements of the water column that is under observation by cutting sections of the water transversely.
This is a large plankton net that is used during vertical plankton tows, which is where we drop the weighted net into the water and then bring it back to the surface once the weighted end touches the ocean floor. This collects plankton from the entire vertical column being sampled. 
This is a flow meter and it is attached at the mouth of the large plankton net that we use for vertical plankton tows. The flow meter can determine the water volume associated with each plankton tow, giving us an idea of the amount of plankton within that volume.
When someone is offshore on a boat, casting the CTD and the plankton net, someone must be onshore using a hand-held pump to collect the plankton that has gathered closest to the shore for comparison against the plankton gathered offshore.
By using modified Hester Dendy stacks, we can measure algae propagule settlement in the intertidal.

This is a modified Hester Dendy stack.
These modified Hester Dendy stacks are bolted directly into rocks in the intertidal and simulate the rugosity of the sandstone rocks, upon which propagules settle. Each set of stacks is left out for a period of 48 hours. 

I switch out the stacks with new ones and take the 48 hour old stacks back to the lab. The stacks are disassembled and I count each individual plate underneath a dissecting scope. I count each coralline spore and red algae propagule that I find and document these numbers in Marley's lab notebook.
To measure barnacle cyprid settlement, we use barnacle plates of two different textures:

Tile Plate
Imprint Plate
I go out into the field every other day to count a total of 18 plates at 2 locations. 
The cyprids settle into the tiny pores of the plates, so I use a hand lens to count them. These cyprids range between 450μm and 600μm in size.
These numbers are entered into a log book as well, to be compiled later in the year for analysis and comparison between different bays.

My time here this summer has taught me many things, but one of the most important things I have learned is to be creative and resourceful with the limited supplies available when conducting research. Funding is not always available and if you want to do the research, you have to find cost-efficient ways to do so. Reduce, reuse and recycle!

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