Maine Striped Bass Foraging Ecology Study
Calling All Anglers: Our UMaine Research Team Wants To Sample Your Striped Bass for Science!
GOT GUTS?
How Can You Help?
Charter Boat Captains
Can help by taking two trained field technicians out on a striped bass charter trip to collect stomach samples non-lethally (via stomach flushing). Please reach out to the project lead, Abby Remick (401-651-1034), for more information if you are willing to take us out with you!
Recreational Anglers
If you harvest a legal sized striped bass (28-31″ TL), DONATE the filleted fish rack with the stomach and other organs! Dropoff locations are listed below and range from Southern Maine to Midcoast.
Instructions to donate a striped bass:
If you don’t want to save the whole rack, put the stomach in a plastic ziplock bag and label the outside with date, location, length, sex (if known).
DROP OFF LOCATIONS:
OUR COOPERATIVE RESEARCH PARTNERS :
Project Information
A University of Maine research team is conducting the one of the first coastwide assessments of striped bass diet in Maine waters. While striped bass diet has been well documented in southern waters along the U.S. Atlantic coast, there has never been a comprehensive study of what they are eating in the Gulf of Maine! This project seeks to understand how striped bass diet varies across fish size, age, sex, location, and season.
Why is this Important?
- Filling a Data Gap
- Striped bass are managed by the Atlantic States Marine Fisheries Commission (ASMFC). In 2019 ASMFC listed the continued evaluation of striped bass dietary needs in relation to health condition as a high priority research recommendation.
- Foraging ecology studies help scientists understand the flow of energy throughout the food webs in Maine coastal ecosystems. Understanding how striped bass feed (seasonally and spatially) will allow us to make important trophic connections between the predator, their prey species, and overall ecosystem health.
- Striped bass are a highly migratory species, and we are interested in how their foraging habits and protein/lipid accumulation shift seasonally and along the coast.
- Contribution to Fisheries Management
- Striped bass are currently a rebuilding stock according to the ASMFC 2024 benchmark stock assessment, making this study timely in addressing important questions about their diets.
- This research can contribute to making informed fisheries management decisions that best support the conservation of the striped bass populations and their prey in Maine.
- Diet data can feed directly into more holistic ecosystem-based fisheries management. This can be used in future striped bass stock assessments as well as future prey species stock assessments (i.e. Atlantic herring, Atlantic mackerel, Atlantic menhaden).
- If we can quantify the abundance and size distribution of commercially harvested prey species that striped bass consume, this can contribute to natural mortality or predation mortality estimates and allow for further protection of key striped bass prey species.
2025 Field Season Updates!
After a successful first season, we were able to sample 287 striped bass thanks to ALL the outstanding involvement from our recreational fishing partners! We also were able to successfully use our non-lethal sampling methods (gastric lavage) on board various charter boats. We will be sampling again in 2026 and would like to expand our connections from last year. Please reach out of you are interested in participating next season!
Some pictures below from the 2025 field season
legal sized striped bass caught from Scarborough Marsh!
Legal sized striper from Scarborough
Using our non-lethal sampling methods in the field!
Yours truly! On a trip out with Capt. Brian
One of our student researchers posing with a fish!
Striped bass rack received from local angler
Our Trusty Intern Gaddum Reddy
~Linguini of the Sea
Grad student Chloe Root’s First Striper #jaws
The night bite is strong!
Aidan Wee doing a striped bass dissection demo for the intern symposium!
Captain Nick’s charismatic dog Link
Some pictures from in the lab (or in the guts)
Sand eels and a squid!
Set of Atlantic herring otoliths (ear bones) found in guts
Check out a youtube short that one of our summer interns put together! Video credit: Gaddum Reddy.
What do the different organs tell us?
Tell us what the fish ate in the last 24 hours! In the lab we dissect the stomach and sort through the guts to try and identify the different organisms in the fish’s stomach.
The muscle tissue can be evaluated with something called stable isotope analysis which can tell us what the fish ate over the last several months. Every fish carries a chemical record of what it’s been eating — kind of like a long-term food log written in its flesh. By looking at two natural tracers in this muscle tissue, we can understand the fish’s long-term feeding habits. In the tissues, we look for the CARBON and NITROGEN values. This analysis is kind of like ecological C.S.I. work! (see figure below for where we take the muscle sample).
Carbon= source of energy and historical feeding habitats (more inshore/offshore/benthic/pelagic)
Nitrogen= a food-chain ladder marker. Higher nitrogen = a higher predator. . This includes information like where the fish has been feeding (on the ocean floor or in more pelagic waters) and where the fish exists in the trophic food web.
Inside of a fish’s head are their otoliths which are the ear bones of a fish. These grow like trees and have rings that we can count to determine the fish’s age! These otoliths also can tell us where the striped bass spawned or it’s point of origin because when the fish is born, it acquires environmental information through it’s gills and into their otoliths.
The liver is a fat storing and processing organ which gets directly impacted by what the fish eats. We use the liver for THREE different things!
- We weigh the liver in the lab and compare that weight to the total weight of the fish (liver: body weight ratio) which can give us an indication of the condition of this fish. Think if a fatter/larger liver as a healthier fish!
- We also use the liver for the same stable isotope analysis as we do for the muscle tissue to understand how different tissues in the fish inform longer term feeding story.
- Lastly, we determine the amount of energetic content (calories) there are in the fish’s liver to further assess body condition and learn how striped bass store fat seasonally!
Fin clips are very easy to collect non-lethally (without having to kill the fish). Think of a fin clip as a GENETIC FINGERPRINT of that individua fish! We can use molecular tools to determine the fish’s genetic structure and population dynamics. Fin clips have also been used for determining sex and age (see image below for where we take the fin clip from).
We can look at the fish’s gonads in the lab which can tell us whether the fish is a male or female and the spawning status (prespawn or postspawn). Most of the migratory stock is female so this information will be important to update past knowledge on the male: female ratio in the Gulf of Maine.
We also collect important prey species to striped bass and use energetic content analysis to determine how much nutritional value a particular prey species provides to the predator. It can also tell us how different prey species vary in their energetic content seasonally and spatially.
All together, these striped bass samples and their prey can help us understand what prey species are supporting striped bass population growth and distribution and help further conservation efforts for this species!
Any Questions?
Please feel free to reach out to us with any questions about the study or how you can participate!
Abby Remick (401) 651-1034, abrielle.remick@maine.edu
Michelle Staudinger (631) 664-7004, michelle.staudinger@maine.edu