Interdisciplinary Seminar: Owen Mulvey-McFerron

An Interdisciplinary seminar from UNC Marine Sciences graduate student, Owen Mulvey-McFerron. Presented by the UNC-CH Department of Marine Sciences and UNC’s Institute of Marine Sciences (IMS). The main location of this event will be in seminar room G201 on the ground floor of Murray Hall on UNC-CH campus in Chapel Hill, NC. The seminar will be streamed live to room 222 at IMS in Morehead City, NC. This event will be held on Monday, April 9th at 12:20pm.

Seminar Title: Swimming Blind: Ocean Acidification Induced Sensory Impairment in Fish

Abstract: As increasing atmospheric carbon dioxide concentrations (pCO2) drive the average pH of the ocean towards more acidic levels, the direct impacts of ocean acidification (OA) on finfish are commonly overlooked. Fish possess complex sensory systems that are vulnerable to impairment, especially their olfactory system (smell) and otolith structures (hearing). Varying levels of impairment have been recorded across multiple taxa in both benthic and pelagic ecosystems. By raising fish larvae and manipulating in situ pH levels to emulate future ocean conditions under increasing pCO2, particular species tended to be attracted to cues that were repulsive at a normal (8.15) pH. Similar studies noted prey avoidance and decreased activity levels in predatory species at low pH. A migratory species displayed physical changes in their saggital and lapillar otoliths, with ~50% increases in mass and a 6% increase in density. Models indicate these changes will increase hearing range by 50%, which could amplify background stimuli or overcrowd cranial structures. The ecological impacts of sensory impairment are profound, ranging from decreased population connectivity to individual larval mortality and resultant trophic cascades. Current climate models indicate that by 2100, pCO¬2 will rise to levels modeled in these studies, necessitating further studies to determine the comprehensive physiological and ecological impacts.