Shore-based angler proudly displaying a spot he caught. Photo credit: Virginia Marine Resources Commission
Spot (Leiostomus xanthurus) occur along the U.S. Atlantic coast in estuarine and coastal waters from the Gulf of Maine to Florida, although they are most abundant from Chesapeake Bay to South Carolina. Spot migrate seasonally, entering bays and estuaries in the spring where they remain until late summer or fall when they move offshore to spawn. Spot mature between the ages of two and three, at lengths of seven to eight inches. Their maximum life span is about six years, although fish older than four years are uncommon.
Spawning takes place in the ocean from fall to early spring and the post-larvae move into estuaries, utilizing low salinity tidal creeks where they develop into juveniles. As spot grow, they move toward higher salinity areas during the summer and early fall and offshore in the fall as water temperatures decrease. Those that summered in the northern portion of their range also move south in the autumn. Spot are opportunistic bottom feeders, eating mainly worms, small crustaceans and mollusks, and organic material. The post-larvae prey on plankton but become bottom feeders as juveniles or adults. Predators such as striped bass, weakfish, summer flounder, bluefish, and sharks eat them in turn.
Spot provide important recreational and commercial fisheries in the South Atlantic, although year-to-year fluctuations in landings are common. This is because spot are short-lived and the catch in most years consists of a single year-class, the strength of which is variable (partly due to environmental conditions prevalent in the spawning and nursery areas).
Spot are caught commercially along the Atlantic coast, particularly from Chesapeake Bay southward. They are harvested by a variety of commercial gears including haul seines, pound nets, gillnets, and trawls. Commercial catches fluctuated widely between 1950 and the early 1980s, ranging from 3.9 to 14.5 million pounds. Such variability is expected because spot are a short-lived species and catch in most years consists of a single year class, the strength of which appears to be determined by environmental conditions that prevail on the spawning and nursery grounds in any particular year. Landings show less year-to-year variability from 1984 to 2011, ranging from 2.1 to 8.8 million pounds. Commercial harvest in 2015 was estimated at 2.16 million pounds, a three million pound decrease from 2014 and a one million pound decrease from 2013. This catch is largely landed by gillnets. Small spot are also a major bycatch of the haul seine and pound net fisheries in Chesapeake Bay and North Carolina, as well as a significant part of the bycatch of the South Atlantic shrimp trawl fishery. However, substantial reductions in the magnitude of bycatch have occurred in the latter fishery in recent years.
For the past three decades, recreational harvest along the Atlantic coast has varied between 1.7 and 6.9 million pounds. Recreational harvest showed an increasing trend from the low of 3.6 million pounds in 1999 to a high of 5.5 million pounds in 2007. In 2015, recreational harvest was 2.27 million pounds.
In August 2017, the Commission’s South Atlantic State/Federal Fisheries Management Board received the findings of the 2017 Spot Benchmark Stock Assessment and Peer Review Report. While the assessment was not endorsed by an independent panel of fisheries scientists (Peer Review Panel) for management use, the Panel agreed with the general results of the assessment that immediate management actions are not necessary. The Panel recommended continued use of the annual traffic light analysis (TLA), established in 2014 to monitor fishery and resource trends, and implement management measures as needed, for spot .
The Panel did acknowledge several improvements with regard to the estimation and inclusion of dead discards from the Southeastern US shrimp trawl fishery. Estimates of these discards indicate they account for a large majority of fish removed from the population annually (via directed and non-directed fishing activities) for both Atlantic croaker and spot. The Panel recommended continued monitoring of these discards and potential inclusion or consideration of these discards in the annual TLA conducted for spot.
A key issue causing uncertainty in the results of the assessment was the disagreement between recent trends in harvest and abundance. Trends in stock abundance for spot are estimated through several federal and state fishery-independent surveys. Typically, if these surveys catch a relatively large number of spot, that would indicate a greater number of spot available to be harvested by their directed fisheries. Thus, scientists and managers would expect a greater abundance of spot would also be reflected through an increase in harvest for that year. Similarly, a decrease in abundance would be expected to be coupled with a decrease in harvest. However for spot, recent harvest numbers are declining while estimated abundance is increasing.
A similar trend is evident in the 2016 TLA for spot. The TLA assigns a color (red, yellow, or green) to categorize relative levels of indicators on the condition of the fish population (abundance metric) or fishery (harvest metric). For example, as harvest increases relative to its long-term mean, the proportion of green in a given year will increase and as harvest decreases, the amount of red in that year will increase. Under the Addendum II to Amendment 1 for Atlantic Croaker and Addendum I to the Omnibus Amendment for Spot, state-specific management action would be initiated when the proportion of red exceeds the specified thresholds (for both harvest and abundance) over two consecutive years for spot.
The 2016 TLA for spot also shows red proportions of greater than the 30% threshold for the harvest metric (Figure 3) and 0% for the abundance metric (Figure 4), indicative of relatively low harvest and high abundance in 2016. Since thresholds were not exceeded for both metrics over the last two years, no management response is necessary for spot.
Spot is one of the 275 sciaenid species worldwide. The Commission manages six sciaenid species, which are commonly called drums, croakers, or hardheads for the repetitive throbbing or drumming sounds they produce. Spot is managed under the Omnibus Amendment for Spot, Spotted Seatrout, and Spanish Mackerel (2011) and Addendum I (2014). The Omnibus Amendment updates all three species plans with requirements of the Commission's ISFMP Charter. As discussed above Addendum I establishes use of a Traffic Light Analysis to evaluate the status of the fisheries and potential coastwide or state-specified management actions (e.g. bag limits, size restrictions, time & area closures, and gear restrictions) based on the annual fisheries evaluation. The TLA has been used as a precautionary framework for fisheries with limited data to allow for a reasonable level of resource management.
In March 2017, a report on Sciaenid Fish Habitat was released including information on habitat for several species, including spot, during all stages of their lives, their associated Essential Fish Habitats and Habitat Areas of Particular Concern, threats and uncertainties to their habitats, and recommendations for habitat management and research. This report is meant to be a resource when amending FMPs in the future for these species.