Monday, May 30, 2016

Corin and Ginger in the office.
It’s projects week – everyone has been working tirelessly in the lab, field and library to slowly expand our collective understanding of nature. We have all been focused on our final projects and we have no scheduled class to distract us. On our own or in small groups we are working on varied projects that include sea urchin and gastropod feeding experiments, trapping European green crab and investigating shell preference in hermit crabs.
Mussel beds at Yachats Beach, one of our study sites. Cormorants and
 other seabirds are visible further back.
"Equipped with his five senses, man explores the universe around him and calls the adventure Science."
-Edwin Powell Hubble

My group have spent many hours in the field this week to survey the invertebrate communities in tide pools. We want to know if mobility is an important factor in allowing species to live in the high intertidal zone where they will be subject to warmer water, lower dissolved oxygen concentrations, and reduced access to open water for releasing their sperm and eggs. We reasoned that mobile species might be able to jump ship and change tide pool if their home gets too warm or begins to dry out. Sessile organisms that are fixed to the rock do not have that luxury and so we expect to see fewer mussels, anemones and barnacles in tide pools in the high intertidal compared to lower tide pools that are submerged for longer each tide. Larger tide pools are presumably less stressful and so we think we will find that sessile organisms are more common in the larger tide pools that we surveyed. A few more hours of data preparation and analysis and we will know if our suspicions were correct. We are eager to see the results of our analysis and find out if our data do show the trends that we expect to find.

Grant and co. employing the transect-quadrat method
that we learnt from Prof Menge in the ecology section.

Grant's group noticed a pattern in the distribution of algae in the high intertidal - Pelvetiopsis and Fucus both inhabit the high intertidal, but Pelvetiopsis is consistently found higher up and their distributions don't appear to overlap. They went to Boiler Bay, Strawberry Hill, Seal Rock and Tokatee Klootchman to do community surveys and they ran small experiments in the lab to measure how gastropod feeding rates and water retention differ between the two species. It looks like Pelvetiopsis is more vulnerable to drying out than Fucus so their must be other factors that maintain their current distribution.

Gastropod feeding experiments with limpets and snails.
Students in our class have seen whales, brown pelicans, harbour seals, sea lions and a pod of orcas in the field this week. Thankfully the weather has been excellent and so while everyone has been working hard this week has still been rather idyllic. 

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