photo of biologists landing a seine.
Biologists land a seine on Rock Creek, 
Anne Arundel County, Maryland.

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A largemouth bass is being measured for length data.
A largemouth bass from Mattawoman Creek, Charles County, Maryland is being measured for length data.

Fish are sampled using a 100 foot beach seine. Two seine hauls are completed at each site with a half hour intervals between hauls. (This allows for repopulation of the seine area). All fish are identified to species and counted; the minimum and maximum length for each species are recorded. Fish from the first seine are kept alive in buckets (to avoid recapture) until the second haul is landed, when they are released. Fish from the second seine are returned directly to the water. Every effort is made to return fish unharmed.

a photo of a bottom trawlA bottom trawl (left) is used to sample fish in the channel area. The trawl is pulled by boat for five minutes and then brought on board. Fish are counted by species, minimum and maximum lengths taken, and returned to the water. Fish which can not be identified in the field are preserved and taken back to the laboratory for identification. Data are recorded on standardized data sheets. Sampling is conducted monthly from July through September.

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For more information, please contact Margaret McGinty ( of the Maryland Department of Natural Resources at (410)260-8630.

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