EAGER: Evaluation and implementation of a newly developed olfactometer for the study of sensory ecology in small marine organisms

University Of Miami, Coral Gables FL

Investigators

Abstract

Chemical cues play critical roles in the life of marine organisms and influence essential behaviors such as finding habitat, food, and mates, and avoiding predators. Research on the role of chemicals in the behavior of animals in the ocean has focused mostly on a small number of organisms, primarily larger, “charismatic” organisms, leaving most species completely ignored. Small organisms are by far the most abundant and diverse and have major ecological importance. The so-called “smaller majority” even includes larval or juvenile forms of some larger species. Yet, their small size has left them particularly neglected. Despite decades of research on the importance of chemicals in the behavior of marine organisms, the sophistication of testing apparatus for small marine organisms in particular has changed little and lags far behind systems used for similar studies on insects. The traditional “set up” for marine studies involves using a two-choice channel flume, which provides a variety of limitations and areas of potential bias. In insect studies, the use of airflow “olfactometers” has eliminated many of these limitations. However, adapting these devices for use on marine organisms is complicated because of the unique properties of water compared to air. We have assembled a team of experts in the fields of hydraulic engineering, sensory biology, and marine biology to develop a device like those used for insect studies that can be used on marine organisms. The goal of this project is to test this new device, which stands to fundamentally change the way we study the behavioral response of marine organisms to chemicals. This project aims to validate a newly adapted olfactometer for use in research on behavioral responses to chemicals in small, aquatic organisms. Testing of the olfactometer will be conducted at the University of Texas’s Marine Science Institute, and the Keys Marine Laboratory, both of which provide modern marine research facilities and easy access to test organisms. Three organisms will be used to validate the olfactometer. These include Daphina spp., fish-parasitic gnathiid isopods, and juvenile stages of scleractinlan (stony) corals. All of these can be easily obtained and data on important chemical cues is already available for them. All organisms will be exposed to a test chemical within the olfactometer, and their behavior observed. The movement of the organism within the olfactometer will be recorded and analyzed using Ethovision XT software, allowing for a high volume of data to be collected, including data indicating attraction or avoidance of chemical stimuli. This research will help place marine researchers on a level playing field with terrestrial researchers by upgrading the toolkit for studies on the response to chemicals by small organisms in an ever-changing ocean This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.