Project: Collaborative Research: Keystone chemicals: Identifying general and universal molecules of fear

Acronym/Short Name:Identifying molecules of fear
Project Duration:2020-04 - 2025-03
Geolocation:Wassaw Sound, GA, US and Dauphin Island, AL

Description

NSF Award Abstract:
Many prey species use chemicals released in predator urine to detect imminent danger and respond appropriately, but the identity of these ‘molecules of fear’ remains largely unknown. This proposal examines whether prey detect different estuarine predators using the same chemical or whether the identity of the chemical signals varies. Experiments focus on common and important estuarine prey, mud crabs and oysters, and their predators including fishes, crustaceans and marine snails. Bioactive molecules are being collected from predators and prey and characterized. The goal is to determine if there are predictive relationships between either the composition of prey flesh or the predator taxon and the signal molecule. Understanding the molecular nature of these cues can determine if there are general rules governing likely signal molecules. Once identified, investigators will have the ability to precisely manipulate or control these molecules in ecological or other types of studies. Oysters are critical to estuarine health, and they are important social, cultural and economic resources. Broader impacts of the project include training of undergraduate and graduate students from diverse backgrounds and working with aquaculture facilities and conservation managers to improve growth and survival of oysters. One response to predator cues involves creating stronger shells to deter predation. Determining the identity of cues used by oysters to detect predators can provide management options to produce oysters that either grow faster or are more resistant to predators. Project personnel is working with oystermen to increase yields of farmed oysters by managing chemical cues.

For marine prey, waterborne chemical cues are important sources of information regarding the threat of predation, thus, modulating non-consumptive effects of predation in many systems. Often such cues are produced when the predators consume the flesh of that prey. In nearly all cases, the specific bioactive molecules responsible for modulating these interactions are unknown, raising the question whether there is a universal molecule of fear that prey respond to. Thus, the focus of the project is to determine the generality of fear-inducing metabolites released by predators and prey in estuarine food webs. The project combines metabolomics analysis of diet-derived urinary metabolites with bioassays to identify the bioactive molecules producing responses in two prey species from different taxonomic groups and trophic levels (oysters, mud crabs). Metabolites are sampled from three types of predators, fish, gastropods or crustaceans. This project aims to: 1) identify bioactive molecules produced by several common estuarine predators from different taxa; 2) compare cues from predators that induce defenses in prey vs. changes in prey behavior; and 3) contrast the identities and effects of predator-released cues with fear-inducing molecules from injured conspecifics. By identifying and contrasting the effects of waterborne molecules that induce prey responses from six predators and injured prey, this project is yielding insights into the mechanisms that mediate non-lethal predator effects, while addressing long-standing questions related to predator-prey interactions. In addition to the search of a universal molecule of fear, the experiments are exploring the role of complementary and distinct chemical information on the specificity of prey responses to different types of predators.

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.


DatasetLatest Version DateCurrent State
Oyster shell hardness from study of eastern oysters (Crassostrea virginica) grown in a nursery with or without exposure to chemical cues from blue crabs2024-10-22Final no updates expected
Oyster shell thickness from study of eastern oysters (Crassostrea virginica) grown in a nursery with or without exposure to chemical cues from blue crabs2024-10-17Final no updates expected
Morphological Characteristics of Oysters from Predator Experiments at the Dauphin Island Sea Lab, AL from July to October 20202023-03-30Final no updates expected
Morphological Characteristics of Oysters from Predator Experiments at the Dauphin Island Sea Lab, AL, May-July 20192023-03-29Final no updates expected
Oyster survival differences in mesocosm experiments at the Dauphin Island Sea Lab, AL between July and August 2019 2023-03-29Final no updates expected
Oyster survival differences in high-quality reefs from Skidaway Island, GA from July to October 20192023-03-23Final no updates expected
Oyster survival difference experiments in low quality reefs in Mobile Bay, AL in September 20192023-03-23Final no updates expected
Juvenile oyster shell strength measurements from predator cue bioassay experiments with treatments including blue crab urine, homarine, and trigonelline conducted at Dauphin Island Sea Lab, Dauphin Island, AL between June and August of 20202022-11-18Final no updates expected
Juvenile oyster shell strength measurements from a dose response assay of chemical cues homarine and trigonelline conducted at Dauphin Island Sea Lab, Dauphin Island, AL in June - August 20212022-11-18Final no updates expected
Juvenile oyster shell strength measurements from a dose response experiment with an array of blue crab urine concentrations conducted at Dauphin Island Sea Lab, Dauphin Island, AL in August - Oct 20222022-11-18Final no updates expected

People

Lead Principal Investigator: Marc Weissburg
Georgia Institute of Technology (GA Tech)

Principal Investigator: Delbert Lee Smee
Dauphin Island Sea Lab (DISL)

Co-Principal Investigator: Julia Kubanek
Georgia Institute of Technology (GA Tech)

Contact: Marc Weissburg
Georgia Institute of Technology (GA Tech)


Data Management Plan

DMP_OCE-1948423_Weisburg.pdf (180.48 KB)
02/09/2025