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2017
Tuesday, April 11th
10:45 AM

Pteropods at Risk: Effects of Ocean Acidification on Pelagic Mollusks

Stacie Bellairs, Whitman College
Alina Nakano, Whitman College

Science 100

10:45 AM - 11:00 AM

Increasing levels of carbon emissions in the atmosphere have direct effects on ocean chemistry and marine habitats. Anthropogenic carbon emissions increase levels of dissolved CO2 in ocean waters, causing ocean acidification. Pteropods are pelagic mollusks with calcium carbonate shells that are vulnerable to corrosion in acidic waters. Our presentation examines the relationship between ocean pH and shell damage of the pteropod Limacina Helicina off the eastern coast of New Zealand. Sampling of water pH in this region varied from 7.98 to 8.10. However, global ocean pH is expected to decrease a further 0.3- 0.4 units by the end of the century, given current emission projections, and these changes may prove more challenging for animals with calcium-best shells. Our research contributes to the growing field of the effects of carbon emissions on marine ecosystems and economies.

11:00 AM

Genetics of Sea Star Wasting Disease

Laurel Field, Whitman College

Science 100

11:00 AM - 11:15 AM

Sea Star Wasting Disease is a highly lethal, widespread marine virus that has devastated sea star populations on the West Coast since 2013. A harmful mutation exists in a gene in sea stars that appears lethal to individuals that have two copies of the mutation (homozygous genotype). Previous studies suggest that individuals with only one copy (heterozygous) have an advantage in dealing with SSWD, implying that surviving heterozygotes would pass the mutation along at higher frequencies, thus preserving the mutation. This hypothesis was tested by surveying recovering, sick and healthy individuals along the central Oregon coast. Our data did not statistically support the hypothesis; nor did we find differences in genotype frequency between healthy and diseased sea stars. Thus, we found no support that selection due to SSWD is affecting this mutation.

11:15 AM

Catch Them if You Can: Assessment of Invasive Lionfish (Pterois volitans) Behavior on Little Cayman, Cayman Islands, to Aid Control Efforts

John DeBuysser, Whitman College

Science 100

11:15 AM - 11:30 AM

Control of the invasive lionfish (Pterois volitans) is a high priority throughout the Caribbean to aid in the protection of coral reefs against the effects of increased predation. Due to few predators, competitors, parasites or disease, culling programs have been the primary means of removal and management. Concerns have been raised that increased culling pressure selects for more cryptic, wary individuals, making spearing increasingly difficult. To assess this concern, over the summer of 2016 400 lionfish were surveyed on coral reefs around Little Cayman, an island in the Caribbean south of Cuba. Preliminary analysis revealed an increase in wary behavior of lionfish at culled sites during the day. Interestingly, regular culls on Little Cayman have not affected the behavior of lionfish at dusk. This study found that evening culls provide greater accessibility to the lionfish population and should be employed whenever possible for enhanced spearing efficiency.

11:30 AM

How to Spend an Alaskan Solstice: Sea Star Wasting Disease and Environmental Education in the North

Nina Finley, Whitman College

Science 100

11:30 AM - 11:45 AM

On the summer solstice in Homer, Alaska, the sun provides light for 21 hours and 44 minutes. What's a person to do with all that time? As the Naturalist Intern with the Center for Alaskan Coastal Studies, I lived at a semi-remote field station where my jobs ranged from guiding tourists around tide pools and rain forests to "raking the cone" in the world's most northern composting toilet to collecting tube-feet from diseased sea stars for genetic analysis. In my presentation, I take you on a 12-minute journey to experience a slice of what you would enjoy as a visitor to the Peterson Bay Field Station. My name is Nina, and I'll be your guide today. Rubber boots optional.