Our Research

The FEED lab will focus on topics such as fish life history, phenology, and habitat in the context of their management as living resources. All topics will include aspects of engaging and educating fishery stakeholders in the northern Gulf of Mexico.

Estuarine Life-History using Otolith Chemistry

Otoliths, or “ear stones”, are anatomical features of bony fishes that aid a fish as it moves in three dimensional space through the water column. The growth of otoliths mirrors the somatic growth of the fish. For fish that live in temperate environments, growth is driven by season – with rapid growth in the summer and slow growth in the winter. These periods of variable growth result in rings (like those in trees) inside of the otolith which allow us to age fish based on the number of pairs of rings. Additionally, otoliths incorporate the chemistry of the environment that the fishes occupy making them reliable indicators for changes in movement as fishes move through water with different chemistry (for example fresh water and salt water).

Sex Specific Differences in Habitat Usage for Spotted Sea Trout in a Dynamic Estuary:

Spotted seatrout inhabit estuaries throughout their life history and have been observed to exhibit sex specific habitat usage in telemetry studies and gillnet surveys (Callihan et al. 2013, 2015). Although telemetry studies and gillnet surveys provide excellent sources of information they are temporally and spatially limited. Through otolith microchemistry we are able to identify temporal patterns in habitat usage as it relates to salinity throughout an individuals complete life history. These patterns are then able to be related to age, growth, sex, and seasonality. Quantifying these patterns informs Essential Fish Habitat for this highly sought after game species.

Healthy Habitats and Healthy Fisheries

Healthy fisheries rely on healthy habitats. Fish do not live in a bubble – they rely on a wide variety of resources to survive and thrive, including food and refuge from predators. Healthy habitats provide these resources to faunal communities in many ways, several of which are poorly or misunderstood. Our lab focuses on the interactions between the community and relative abundance of fish across multiple marine and estuarine habitats.

Impacts of Estuarine Habitat Restoration on Fish and Invertebrate Communities in Coastal Louisiana:

To combat estuarine saltmarsh loss throughout Louisiana, restoration projects have been conducted to rebuild the marsh protect the marsh from further eroding. Following these projects, our lab seeks to understand now the local abundance and community of fish and invertebrate species may change in these now-altered habitats. We use numerous fisheries independent sampling gear types (i.e. longlines, gillnets, throw traps, seines) to get a thorough picture of species dynamics across a range of feeding types, body sizes, and habitat use in the ecosystem.

Survey Methods and Site Suitability for Oyster-Based Living Shorelines:

Phenology of Fish Movement and Fishery Recruitment

Phenology is the rhythm of the natural world. As the year moves on, we see ecological and biological changes driven by seasonal changes in temperature, weather, and light. Evolutionary, marine fish have developed cues on when to move and spawn based on these changes in seasons. However, as the climate on our planet changes, migratory and reproductive cues tied to temperature and weather may come at a different time than they have historically. These differences in timing may alter the behavior of fish and result in ecological match and mismatches resulting in population-level effects. Our lab works to understand the role that phenology plays in the life histories of marine fish and how environmental changes may alter those life histories. Recently, our lab has begun to focus on the phenology of recruitment of estuarine fishes, and how over decades the phenology of some species have changed – and others have stayed the same.