There have been many words written about menhaden and how they support various segments of the wild and the human world. Unfortunately, there has not been very much real science directed at menhaden and how they move about, spawn, and react to different water temperatures and oxygen levels.
The current regulations that govern the number of menhaden that may be taken from the Chesapeake Bay are set to simply prevent overfishing. They have no basis in science because there is no scientific study to back those figures up.
Today, there is a group of very well-qualified Atlantic menhaden researchers tasked to develop a scientifically defensible and ecologically meaningful Chesapeake Bay harvest cap. This group is funded by the Science Center for Marine Fisheries.
Members of this group are from the Batten School of Coastal and Marine Sciences & Virginia Institute of Marine Science at William & Mary, the Chesapeake Biological Laboratory at the University of Maryland Center for Environmental Science, and the National Oceanic and Atmospheric Administration.
One method that has been used with success with other fish is tagging. As you might have guessed, tagging a menhaden is not as simple as tagging a flounder or a striped bass.
What the researchers plan to do is capture some menhaden and hold them in tanks until they become used to captivity. Then they will insert passive integrated transponder tags in half the fish and no tags in the other half. These tags can be read when they pass by a receiver system. The hope is the tagged fish will show no ill effects.
The next step requires a visit to ocean harvesters where tests will be preformed to see if the tags can be detected during commercial operations. A known number of tagged fish will be placed in the catch and receivers will be installed in the pump hose, the chute where the fish enter the boat’s hold and at Omega Protein’s processing facility.
If all of this goes as planned, I suppose the next project will be tagging large numbers of menhaden in the Chesapeake Bay next summer. Then those receivers will have to be installed on the boats that work the bay, the pound nets will have to be monitored and all of this is going to cost a lot of money. If we get good science instead of guesswork, it will be worth the cost.
Tagging studies have found information that has contradicted long-held beliefs about certain fish species.
Take striped bass, for instance. For years, we thought they hugged the East Coast as they moved from their spawning grounds in the Chesapeake Bay to their summer grounds off New England. Now, thanks to satellite tags, we have found out that some stripers move well east, as far as the Hudson Canyon, and hang out around the Nantucket Shoals during the summer. From there, they may swim down to the mouth of the Chesapeake Bay and enter via a channel used by German mine layers to set mines into the mouth of the Chesapeake Bay.
Unfortunately, menhaden are too small for satellite tags, but once the scientists get these PIT tags figured out, the information could be just as interesting.
For example, do the menhaden in the Chesapeake Bay mix with those in the Atlantic Ocean? Can the tags be selective? In other words, if we tag menhaden in the Chesapeake Bay and some in the Atlantic Ocean, will they be able to tell the difference?
When you tag a striper, that tag has a number, and when you fill out the corresponding card with the date of when, where and how you caught the fish and the size of the fish when captured before sending the card to the agency sponsoring the study, all that information goes into a file. When the fish is recaptured, the new information is compared to the original and the data is gathered from the comparison.
About the only way I can see for the same sort of study to take place with menhaden is for expert cast net operators to catch large numbers of menhaden, have large numbers of trained personnel standing by to inset the PIT tags as quickly as possible into the fish and then release them. At the same time, they need to have large numbers of personnel record the number of fish caught and tagged, the exact location and the time of day, date and weather conditions.
There will have to be large numbers of everything because menhaden will be set upon by numerous outside forces before they are harvested by commercial fishermen. Since it will only be commercial fishermen who will have the detectors in their equipment, they are the only ones who can detect the presence of the PIT tags.
Eric Burnley is a Delaware native who has fished and hunted the state from an early age. Since 1978 he has written countless articles about hunting and fishing in Delaware and elsewhere along the Atlantic Coast. He has been the regional editor for several publications and was the founding editor of the Mid-Atlantic Fisherman magazine. Eric is the author of three books: Surf Fishing the Atlantic Coast, The Ultimate Guide to Striped Bass Fishing and Fishing Saltwater Baits. He and his wife Barbara live near Milton, Delaware. Eric can be reached at Eburnle@aol.com.




