66.8% = DEFICIENT
How It’s Calculated
FINDEX is a novel way to gauge whether the status of a fish population is trending up or down. Management of most fish species in North Carolina is guided by stock assessment models developed by various groups of scientists.
The calculations in our FINDEX metric measure the gap between the desired condition of a fish stock (the Target reference value) and the existing condition (the most recent data year in the model called the Terminal value) as determined in each stock assessment. The gaps between Target and Terminal values are calculated as ratios.
For example, if the Target and Terminal values are the same, there would be no gap and the ratio would be 1.0. The multiplier on our FINDEX barometer would set the FINDEX value at 100% in this example and assign a stock status designation of “Stable.” Categories on the FINDEX barometer are measurable as they track the extent of the gap either above or below the “Stable” designation.
For Speckled Trout, the FINDEX gap assessment compared Target and Terminal values of Fishing Mortality (F30%) and Spawning Stock Biomass (SSB30%) from the stock assessment developed by the NC Division of Marine Fisheries.
The Terminal year (the most recent data year) in the stock assessment model was 2019; however, the scientists used the average of the 2017-2019 values for their calculation of the 2019 Fishing Mortality value, so we chose to do the same for all data reported here.
FINDEX recognizes that Fishing Mortality (lower is better) and Spawning Stock Biomass (higher is better) are inversely related, so we adjust our gap calculations whenever the two ratios are considered together.
Here's the FINDEX formula used for Speckled Trout:
- (0.506 x 1.32) x 100 = 66.8%
- FINDEX = 66.8% for 2019
- 66.8% = DEFICIENT
What Does Deficient Mean?
“Deficient” is assigned to any stock with a FINDEX value between 50 and 99%.
The most recent peer-reviewed stock assessment model for Speckled Trout (2019 data) tells a mixed story.
Spawning Stock biomass (the estimated metric tons of females in the population) performed well relative to the Target reference value, indicating the population was not “overfished”. On the other hand, the Fishing Mortality estimate was too high relative to the Target reference value suggesting “overfishing” was occurring.
Stock status suggesting “overfishing” is occurring, while at the same time indicating that the stock is not “overfished” is confusing and difficult to interpret. Our FINDEX metric remedies this confusion by classifying Speckled Trout status as “Deficient”.
FINDEX Status Over Time
The stock assessment model for Speckled Trout provides point estimates of Fishing Mortality and Spawning Stock Biomass for each year covered in the data set. We’ve compared the Target reference values to these annual point estimates and calculated the ratios (gaps) for each data year through the period 1991–2019.
Applying the FINDEX gap assessment to the entire time series provides the following stock status trendline:
Commercial Speckled Trout Trends
The graph below illustrates commercial harvest trends for Speckled Trout from 1985 through 2021. In 2021, 676 commercial fishers recorded 12,087 trips harvesting 694,803 pounds of Speckled Trout valued at $1,755,558. Commercial landings in 2021 were the highest on record (with data going back to 1950), exceeding 600,000 pounds for the first time since 1991. Supporting data was sourced from the North Carolina Department of Environmental Quality.
Commercial Speckled Trout Harvest
No Data Found
Recreational Speckled Trout Trends
The graph below illustrates recreational harvest trends for Speckled Trout from 1989 through 2021. In 2021, recreational anglers harvested an estimated 1,223,508 Speckled Trout weighing 2,241,421 pounds. Mean length in 2021 was 17 inches and mean weight was 1.8 pounds per fish. The estimated number of Speckled Trout released recreationally in 2021 was 6,332,064 fish. An estimated 2,778,386 fishing trips were taken in pursuit of Speckled Trout in 2021. Supporting data was collected through the Marine Recreational Information Program as sourced from the North Carolina Department of Environmental Quality.
Recreational Speckled Trout Harvest
No Data Found
How Do We Get to World Class?
FINDEX can also be used to determine when a population has reached “World Class” status. Because FINDEX factors performance of both Fishing Mortality and Spawning Stock Biomass into the metric, multiple combinations of these values could potentially lead to a World-Class designation.
Speckled Trout Target values for Fishing Mortality (0.38) and Spawning Stock Biomass (1,714 metric tons) have been established by the management agencies. The existing estimates (2019 values) are 0.75 and 2,250 metric tons. Under one potential scenario, if Fishing Mortality was to drop to the Target, and Spawning Stock Biomass was to increase to 3,450 metric tons, then the FINDEX value would exceed 200% on our barometer. The vision of the NC Marine & Estuary Foundation is to see our coastal stocks exceed Target expectations as we pursue World-Class fisheries and thriving coastal economies.
2023 Harvest Seasons for Speckled Trout
- The recreational limit for Speckled Trout is currently 4 fish per day, with a minimum size limit of 14-inches total length.
- Commercial fishing operations for Speckled Trout are limited to 75 fish per day, and a 14-inch minimum size limit is also in effect. No annual quotas currently exist. Proclamations for Speckled Trout can be found here.
- North Carolina’s state record Speckled Trout was caught from the Neuse River in 2022 by Todd Spangler
- The record-breaking fish weighed 12 pounds and 8 ounces
Did you know?
- Speckled Trout are subjected to “cold stun” events when water temperatures drop below 40oF, and fish kills are often observed when temperatures remain below 37oF. Natural mortality is a serious concern for Speckled Trout stocks, and can help explain the occasional dips in commercial and recreational harvest trends as seasons have been closed periodically (2011, 2014, and 2018) due to winter fish kills
- Ten-year old Speckled Trout have been observed in Virginia and Florida, with fish as old as age 9 collected in North Carolina
- Speckled Trout are considered a type of drum, and are in the same family as Red Drum, Black Drum, Spot and Croaker
FINDEX provides the most recent stock status updates for a variety of North Carolina’s finfish species. As new data is made available, FINDEX values will be revised. If you’re interested, FINDEX can be delivered to you each month if you subscribe to our Think Coastal newsletter.
Formed in 2017, the N.C. Marine and Estuary Foundation and its brand “Think Coastal” were established to support world-class fisheries and thriving coastal economies. In achieving this goal, the N.C. Marine and Estuary Foundation equips citizens, researchers, legislators, policymakers, stakeholders, and other organizations with high-quality scientific information to help solve challenging fisheries issues.
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