Red Drum Satellite TrackingNorth Carolina Marine & Estuary Foundation
- Number of Fish Tagged in 2024: 10
- Number of Fish Tagged in 2025: 33
- Location Tagged: Along the North Carolina coast
- Tag Type: SeaTag-GEO pop-up satellite tag
- Cost per Tag: $2,500 including monthly subscription fees
Overview
As North Carolina’s state saltwater fish, the red drum is not only a popular target for anglers but also a species of significant economic importance. Each year, anglers average 3 million fishing trips in pursuit of red drum, contributing to the $4 billion spent on coastal fishing in North Carolina. To unlock the story of red drum movement, the Foundation has joined forces with the NC Division of Marine Fisheries to launch a groundbreaking red drum satellite tagging project along the North Carolina coast.
The Issue
As identified in the Division’s red drum research needs, there is more to learn about the stock structure, spawning migrations, and habitat preferences of adult red drum. Being a species of economic importance, several key questions remain unanswered: Where do red drum spawn? How far do they travel? How often do they pass through the ocean inlets, and do they head north to Virginia or make their way beyond South Carolina?
Our Solution
To address these questions and more, the North Carolina Marine & Estuary Foundation has joined forces with the North Carolina Division of Marine Fisheries to launch an innovative red drum satellite tagging project along our coast. Adult red drum are affixed with satellite tags that transmit daily positioning data from each fish to the Argos satellite network and then to the computer software.
Red Drum
What's Next?
Building on a successful 2024 pilot study that provided valuable insights, the Foundation will expand its efforts. In 2025, 20 Red Drum will be tagged by Foundation staff with the help of local recreational fishing guides along the coast, while the Division of Marine Fisheries will tag an additional 20 during its longline survey in the Pamlico Sound. Tags will remain active for 4, 6, or 12 months, offering new data on the behavior and movement of North Carolina’s iconic saltwater fish.
Displaying the Data
To display the movement data we continue to collect, our Foundation partnered with Mapotic to develop an interactive red drum tracking platform. This platform shows near-real-time locations whenever a tag connects to the Argos satellite network. These opportunistic updates occur when a red drum comes close to the surface at the same time a satellite is passing overhead.
FAQ
What are the goals of the tracking project?
The goals of the red drum tracking project are to better understand the movement and behavior of red drum by answering key questions such as:
Residency: Do red drum remain within North Carolina’s sounds and waterways throughout the year, or do they migrate to other states?
Migration Patterns: If they leave North Carolina, where do they travel, what routes do they use, and how long do they remain away?
Spawning Behavior: When and where do red drum spawn, and what environmental factors influence their spawning activity?
Overall, the project seeks to provide insights into red drum movement, migration, and reproduction to help guide management and conservation of the species.
How do the satellite tags work?
The SeaTag-GEO “Precision Migratory Tracking Pop-Up Satellite Tags” used in the red drum tracking project collect and transmit environmental and positional data to track fish movements over time. The tags are attached to red drum and remain in place for a set period (from one month up to a year in this project). Each tag is pre-programmed to detach (“pop-up”) at the end of its deployment period and float to the surface, where it transmits stored data via satellite. The tag’s wraparound solar panel serves dual purposes: it powers the device and measures ambient light uniformly for accurate data collection.
What types of data are collected?
- Geomagnetic Field Values – Used to estimate latitude based on changes in the Earth’s magnetic field.
- Light Measurements – Used to estimate longitude and calculate day length, helping determine the fish’s position.
- Temperature Readings – Record the water temperature at various depths, offering insights into habitat preferences.
- Noon Time Estimates – Help refine location estimates by comparing solar noon times across days.
- Solar Panel Voltage – Indicates light intensity, supporting light-based position calculations and confirming the tag’s surface activity.
What do the three status colors mean?
- Active: Tag is deployed and communicating occasionally with the Argos satellite network prior to pop-up
- Standby: Tag is deployed and awaiting opportunistic communication with the Argos satellite network prior to pop-up
- Inactive: Tag has detached from the fish and tracking is complete
Note: Satellite tags provide the most reliable information when they detach from the fish as programmed and “pop-up” to the surface. Once at the surface, the floating tag transmits an assortment of daily data that can be used to produce high-accuracy position tracks. Prior to pop-off, if the red drum is at or near the surface while a satellite is positioned overhead, opportunistic transmissions can occur, providing preliminary spatial data.
Why does the track show the fish traveling over land?
The tracking platform connects consecutive location points with straight lines. When there is a gap in transmissions or the fish moves quickly offshore, the software may draw lines that appear to cross over land. This does not mean the fish actually traveled over land—it simply reflects how the system links available data points when continuous location information isn’t available.
What should you do if you catch a tagged red drum?
If you reel in a red drum with a tag, congratulations—you’ve found an important part of a research project!
Each tagged fish has two tags:
- A satellite tag (please leave this on the fish)
- A red $100 reward tag
Here’s a three-step process to follow:
- Cut off the red reward tag.
- Leave the satellite tag on the fish and release it safely back into the water.
- Mail the red tag to the address printed on it.
Note: Include your name, mailing address, date you caught the fish, and the general area or waterbody where it was caught.
Why did we choose this tagging method?
This tagging method is experimental, but it’s based on techniques that have worked well in other studies, especially with Pacific cod, a species similar in body shape to red drum.
The tag is attached using a loop of strong monofilament line that’s carefully inserted about two inches below the fish’s top (dorsal) fin. Two small plastic discs are then added and crimped snugly against the fish to hold the line securely without causing irritation. The satellite tag is fastened to this line so it “rides” smoothly over the fish’s back as it swims.
While the tag weighs 42 grams in air, it becomes much lighter in seawater thanks to a built-in float—weighing only about 8 grams, or roughly 20% of its original weight. When the tag eventually detaches, only a small cap remains on the fish, minimizing any lasting impact.
