Summer Flounder Stock Assessment Update: 6 Things To Know

July 2010

1. How do we assess the population?

The information on summer flounder was integrated into a useful mathematical model called an age-structured assessment program (ASAP). The population is modeled, much as the U.S. Census Bureau models human populations using similar data—population size at age, growth rates, age at maturity, reproductive potential and success, life span, and removals by deaths. The summer flounder stock assessment model uses widelyaccepted and commonly-used fishery science principles to analyze the population size. The data used have been collected annually since 1982 from fish caught (recreational and commercial) and fish sampled in the ocean (taken on research surveys.)

2. How do we "check" the models?

By conducting a benchmark assessment such as the June 2008 Stock Assessment Workshop (SAW/SARC 47) for summer flounder. A working group of fishery scientists conducts a thorough evaluation of available data, methods and models, and selects those that best represent the summer flounder population. This work is then “peer reviewed” by a group of independent experts. The summer flounder assessments have been peer reviewed 17 times in the last 26 years. The peer reviews have validated assessment results and helped improve stock assessment methods and modeling. Stock assessment updates are conducted in the years between peer reviews. Updates include the most recent data, but apply the exact same methods that were validated by the peer-review. The 2010 stock assessment update included data through 2009.

3. Is the summer flounder stock rebuilt?

The June 2008 Stock Assessment Workshop (SAW/SARC 47) set the rebuilding goal as 132 million pounds of spawning stock biomass. The most recent stock assessment update indicates that the current spawning stock size is about 89% of the biomass goal, and that rebuilding can occur on schedule (by Jan. 1, 2013), given continued success in staying at or below annual commercial quotas and recreational harvest limits.

4. Have rebuilding targets been set too high in the past?

No, but since 1999 the rebuilding targets have been declining. None, however, has ever been achieved. Targets often change over time as fishery scientists improve models and methods, and as new data are available on how the stock responds (grows, produces young, dies) to ecosystem conditions and fishing rules intended to end overfishing and rebuild the stock.

5. Are we overfished or overfishing?

No, but the stock is not yet rebuilt and fishing harvests need to stay within the annual limits to ensure that it will be. 6. Have harvest quotas and limits been set too low in the past? No. The quotas and limits have been set consistent with the scientific advice, and have been exceeded in most years since 1982. Overfishing was occurring from 1982-2006; however it was not occurring in the three most recent years 2007 - 2009. The most recent stock assessment update suggests that initial quotas and limits for 2011 may be set slightly higher than those in 2010 without compromising rebuilding goals if 2010 quotas and limits are not exceeded.