Fishery-Dependent Data Helps Scientists Understand Trends in Harvest
Taking note: Technicians measure and record information about the commercial catch at a fish house.
By Patricia Smith and Kelly Odom
Fish Eye News
N.C. Division of Marine Fisheries
An important element of any stock assessment is looking at what the fishermen are catching.
It’s called fishery-dependent data, which means it is information collected about the fish that commercial and recreational fishermen catch. And it is just as important to a stock assessment as the independent data collected by biologists in the field, said Laura Lee, senior stock assessment scientist with the N.C. Division of Marine Fisheries.
“Without it, it would be difficult to do a stock assessment,” Lee said.
The division manages several programs designed to collect biological and effort data on commercial and recreational landings and predominant gear used along the state’s coast.
Recreational landings data are collected through a number of different survey programs, collectively called the Coastal Angling Program.
The largest and most comprehensive of these is the Marine Recreational Information Program, which includes dockside creel surveys, telephone surveys, head boat observer sampling and for-hire surveys.
“There’s about 15 recreational port agents in the field each day sampling individuals and collecting data on fishing trips,” said Coastal Angling Program manager Doug Mumford. “They survey fishermen at the boat docks, fishing piers, charter facilities and at the beach and banks.”
The agents primarily take information on what anglers catch, where they catch it and what was thrown back. They also measure and weigh the fish.
Through a for-hire survey, surveyors contact 10 percent of the charter, head and guide boat operators each week to determine the number of fishing trips they made.
Similar information is gathered from fishing piers through a fishing pier reporting program.
The data from the for-hire surveys and fishing pier reporting program is combined with other surveys that provide information about what fishermen are catching on the boats and piers.
All this information goes into a database that can be queried with any number of fields about recreational landings in North Carolina coastal waters.
“We can tell you what size they were, we can tell you where they caught them, we can tell you where the anglers who caught them were from,” Mumford said.
Data on commercial harvest are collected through a Trip Ticket Program and other sampling programs, such as fish house surveys, telephone surveys, on-board observers and vessel monitoring systems.
The Trip Ticket Program began in 1994 and was designed to record every single sale that takes place between a licensed commercial fisherman and a licensed seafood dealer in North Carolina.
When a fisherman comes to a dealer to sell his catch, the dealer fills out a trip ticket about what they purchased from which fisherman, the date and place of the harvest, the gear type used, and the date it was landed at the dealer’s docks.
The dealer is required to turn his trip tickets in every month. Data entry clerks then enter the information into a computer database. Some species that are monitored under quotas also have additional daily reporting requirements.
“With this data we can determine the number of fishermen, vessels, dealers, and trips that occur in a North Carolina’s commercial fisheries, as well as characterizing our various fisheries,” said Alan Bianchi, trip ticket coordinator for the division.
The Trip Ticket Program does not, however, show how many fish were thrown back or how many fish the fisherman took home to his own freezer. It also does not record the quantities of gear used.
This information is obtained through observer coverage, where division technicians go out on the water with the commercial fishermen.
Observers count, measure and weigh a sample of what the fishermen catch, be it the target species or bycatch. They document the time and location of the catch, describe the gear used, record interactions with protected species and collect information on environmental conditions.
Division technicians also go into the fish houses and retail markets to sample landed commercial catches.
Technicians select a representative sample of the commercial catch, measure and weigh all fish and shellfish in the sample, and interview fisherman for specific gear, effort, and location information regarding their catch, said Katy West, division Pamlico District manager.
“Biological samples from the fish houses help us characterize the size and age distribution of the commercial catch, which gives us more information about the harvested population,” Lee said.