Friday, April 17, 2009

Week 3 Marine Fishes

Week 3 started out by welcoming Scott Heppell, Assistant Professor (Senior Research), from Fisheries & Wildlife to our class to teach the Marine Fishes section.

Monday started by heading out to the Yaquina Bayfront and netting fish using a seine net to collect shallow bay fishes. These specimens were then taken back to our lab for study and classification.

Tuesday was a day filled with lecture and a disection of fish. We all disected either an Albacore Tuna, a Black Rockfish or a Dover Sole. We looked at their internal organs and how they are specialized for the lifestye of the fish: such as the large heart of the Tuna, fitting for its high energy lifestyle.

On Wednesday we returned to Strawberry Hill but this time with hand nets in hand to collect tidepool fishes. We then returned to the classroom for a facinating lecture on ontogenetic shift which is a change in lifestyle associated with growth and development. Later, Scott presented a section on the reproductive biology of fishes.

On Thursday Boiler Bay was our destination to collect marine fish while Gray Whales fed just offshore of the bay. Later in the day during lab we learned how to use otoliths (the ear bone of fish) to determine the age of fish and what we can learn about their life history from the spacial arrangment of the rings. This data especially comes in handy when studying the effects of climate change on marine ecosystems. By looking at the rings scientist can decifer whether it was a good year of biological productivity or whether food sources were scarce (much like that of the rings of terrestrial trees) often linked to an increase of temperature in the oceans.

Friday was spent in lecture learning about Fish Habitat, the Red Grouper as an ecosystem engineer, and about fisheries and their impact on the ocean's resources. Also preparation took place on the group project determining which areas would be suitable to conserve as Natural Resource Reservations.

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