What is ChesMMAP?

R/V Virginia from the air

ChesMMAP 200 x 12 cm net in the water

Haulback! Time to empty the net and sort the catch.

ChesMMAP Sorting Table

Back deck of the R/V Virginia outfitted with ChesMMAP Gear

R/V Virginia

Emptying the catch from the net

The Chesapeake Bay Multispecies Monitoring and Assessment Program, ChesMMAP, began in 2002 and was developed to assist in filling data gaps, and ultimately to support Bay-specific, stock-assessment modeling activities at both single and multispecies scales. ChesMMAP was designed to maximize the biological and ecological information collected for several recreationally, commercially, and ecologically important species in Chesapeake Bay. The survey uses a large-mesh bottom trawl to sample juvenile-to-adult fishes from the head of Chesapeake bay at Poole's Island, MD to the mouth of the Bay just outside the Chesapeake Bay Bridge Tunnel.

Survey Goals

To estimate population sizes for priority species
To quantify geographic and seasonal distribution of these species
To quantify major links in the Bay's food web by conducting stomach content analysis for all species sampled
To define the seasonal length and age structure of the fish and elasmobranch populations by taking otolith (ear bone) or vertebrae samples from the individuals collected.

Field Methods

GIS Maps

Catch Maps

These interactive maps provide a dropdown menu to select a species to view catch numbers and biomass integrated with a quantitative chart summary and water quality overlays.

Archived Catch Maps

Archived Water Quality

Largest Fishes Map Tour

Abundance Indices

• Atlantic croaker	• black seabass
• blue crab - adult female	• blue crab - male
• bluefish	• butterfish
• clearnose skate	• kingfish spp.
• northern puffer	• scup
• spot	• striped bass - March
• striped bass - November	• summer flounder
• weakfish	• white perch - March
• white perch - November

Data Uses

Fishery-independent data resulting from the ChesMMAP Trawl Survey have been requested by stock assessment scientists for a variety of species. Again, because of the relatively short time series currently available for this survey, the incorporation of abundance indices generated by the ChesMMAP Survey has only been possible for two species: scup and weakfish. Similar to the situation with NEAMAP, the biological data produced by this survey have been included in the assessments for alewife, blueback herring, bluefish, butterfish, summer flounder, scup, spot, and weakfish. The assessment scientists expressed their desire to include these data in future assessments as well, again indicating that time series length, and not data quality, is the issue at hand. Currently, ChesMMAP survey data are being used to guide the assessments for Atlantic croaker and black drum. An informal assessment of sheepshead data collected by ChesMMAP has been supplied to the Virginia Marine Resources Commission to support review of current management regulations for this species in the Commonwealth, and summer flounder catch and length-frequency data have been used to support the liberalization of recreational harvest regulations for 2011.

From the perspective of ecosystem-based multispecies modeling and management, ChesMMAP diet data have been used to support the development of a fisheries ecosystem model of Chesapeake Bay and a multispecies virtual population analysis of Atlantic menhaden along the U.S. east coast. These data have also been used to both formally and informally quantify the predatory impact of fishes on their prey (e.g., striped bass, weakfish, and bluefish consumption of menhaden; striped bass impact on blue crabs). It is expected that the inclusion of ChesMMAP diet data into multispecies efforts will increase as these relatively new assessment approaches continue to develop. Finally, ChesMMAP abundance and biological data for summer flounder were used to explore yield-per-recruit and egg-per-recruit analyses for this species under a variety of regulatory scenarios for the recreational fishery. The results of this study were requested and reviewed by the ASMFC in their discussions of a possible slot limit management regime for this species.

Uses of Data Generated by the Chesapeake Bay Multispecies Monitoring and Assessment Program (ChesMMAP) Trawl Survey, 2007-2017

Assessment Related (NMFS & ASMFC)

Data requested for and incorporated into past assessments

Atlantic Menhaden – Predator diet data for inclusion in Multispecies VPA
Atlantic Sturgeon – Abundance data for ESA listing and subsequent re-evaluation
Black Sea Bass – Abundance, distribution, & age
Bluefish – Age
Scup – Abundance, distribution, & age
Striped Bass – Abundance, distribution, length, & age
Summer Flounder – Abundance, distribution, & age
Weakfish – Abundance, distribution, & age

Data requested and evaluated for but not incorporated* into an assessment

*Due to short time series of data & relatively low catches available, NOT because of data quality.

Black Drum – Abundance, distribution, length, sex, maturity, & age
Bluefish – Abundance, distribution, length, sex, maturity, & age
Butterfish – Abundance, distribution, length, sex, maturity, & age
River Herring (Alewife & Blueback) – Abundance, distribution, length, sex, & maturity

Data requested for an assessment & results currently pending

Atlantic Croaker – Abundance, distribution, length, sex, maturity, & age
Spot – Abundance, distribution, length, sex, maturity, & age
Tautog – Abundance, distribution, length, sex, & maturity

Virginia-Specific

Sheepshead – Data provided to Marine Resources Commission for review of harvest regulations
Summer Flounder – Setting of conservation equivalency measures

Additional Research Efforts

Atlantic croaker, black drum, kingfish, & spot - population genetics with South Carolina DNR
Atlantic croaker & spot - ageing exchange with ASMFC partners
Atlantic croaker, striped bass, & weakfish - collaboration with the VIMS Juvenile Fish and Blue Crab Trawl Survey to explore the relationships between recruitment indices and adult abundance
Atlantic croaker & white perch - quantified capture efficiency of the survey trawl for these two species, which both established necessary protocols for such work and facilitates the estimation of absolute abundance for these species
Black sea bass - hard part (scale/otolith) comparison for ageing
Blue crab – collaboration with Conservation Biology division at VIMS to conduct a bay-wide tagging program meant to evaluate the effectiveness of the Chesapeake Bay blue crab spawning stock sanctuary
Bluefish, striped bass, summer flounder, & weakfish – development of consumption estimates for these top piscivores in Chesapeake Bay
Coastal sharks & Atlantic sturgeon - tagging studies in collaboration with NMFS.
Multispecies – supported investigation of community-level responses of fish condition to environmental covariates in Chesapeake Bay
Scup - hard part (scale/otolith) comparison for ageing
Summer flounder
- supported sampling to quantify first year growth and habitat preferences
- hard part (scale/otolith) comparison for ageing (ongoing)
- provided biological data to support yield-per-recruit/egg-per-recruit analyses to examine various regulatory scenarios for the recreational fishery (with ASMFC)
- investigation of trophic dynamics which resulted in this species being classified as one of the top piscivores in the Chesapeake ecosystem
Tautog - population genetics with Virginia Marine Resources Commission (ongoing)
Striped bass - sampling to identify prevalence and severity of Mycobacterium infection in the coastal migratory population; showed infection contributed both to reductions in growth rates and to increases in natural mortality rates
Sampled livers of multiple species for contaminant analysis in collaboration with Clemson University
Expanded sampling into tributaries of Chesapeake Bay to sample fishes for contaminant analysis as part of the National Coastal Assessment effort (collaboration with the EPA)
Collected voucher specimens of multiple species in collaboration with Smithsonian to establish a genetic library of fishes in the Chesapeake Bay
Provided data on multiple species to support the development of an ecosystem model for the Chesapeake Bay
Completed an analysis of 10 years of ChesMMAP data to identify patterns and drivers of the demersal fish community in Chesapeake Bay
Began testing of a 200 x 12 cm, three-bridle, four-seam survey trawl for use by ChesMMAP. This net is more efficient than the current gear and is more comparable to the trawls used by NEAMAP along the coast and the Northeast Fisheries Science Center offshore. Specifically, this “200 x 12 cm” net is identical in design, but half of the size of, the nets used by those ocean surveys.
Supported research conducted by 4 Master’s and 3 PhD students to date
Resulted in development of a manuscript focused on quantifying the patterns and drivers of condition across a range of species inhabiting Chesapeake Bay
Received over 200 visits to our online catch and diet databases since initialized in early 2012

Reports

Funding

ChesMMAP is currently funded by Wallop-Breaux funds from the Virginia Marine Resources Commission and the Commonwealth of Virginia.