Thursday, May 13, 2010
A conversation with Mary Groves
I am the Southern Region Inland Fisheries Manager for the Maryland Department of Natural Resources (MD DNR). Our purpose is to monitor and manage freshwater fish populations in Anne Arundel, Prince Georges, Calvert, Charles and St. Mary’s Counties. This also includes tidal freshwater such as the areas in the Potomac and Patuxent that still have a tidal fluctuation but the water is fresh or semi-fresh (0-5 ppt salinity).
These areas hold predominantly freshwater species like largemouth and smallmouth bass, walleye, various sunfish, various catfish and even an occasional trout. In very dry years, blue crab, spot and croaker may also be found. This is because the salt wedge can be driven way upstream during high tide due to the lack of freshwater supplied by rainfall.
Describe the Potomac? What makes it unique?
The Potomac River below Washington DC is unique because of the diversity and abundance of fish that live here. Add to that the miles and miles of fishable tributaries, the beautiful wildlife and the historical wealth of the surrounding area and you can’t go wrong spending a day on the Potomac.
What should anglers know about fishing this river that runs through the capital?
There are several important things that you need to know when fishing the tidal Potomac.
First, there is no reciprocal license agreement between Maryland and Washington DC. You need a fishing license for each area if you plan to fish around Washington DC and are not familiar with the river. There are no markers telling you when you’ve crossed into Maryland or Washington.
The second is you need to be able to identify the fish you keep, or at least have some fish ID guide handy. This is because there are some fish that you are not allowed to keep at all such as shad, stripers (limited season) and herring (Maryland).
How are various fish populations doing including the shad, stripers and of course the snakeheads?
A moratorium is still in effect for both hickory and American shad meaning that it is illegal to possess either species regardless of where you fish. Federal and State agencies have been working for years to restore the shad population in the Potomac and annually stock hatchery raised fish in order to supplement current populations.
A limited fishing season is still in effect for striped bass and can change from year to year so it’s important to check on current regulations if you plan to fish for stripers.
Northern Snakehead continue to expand their range in the tidal freshwater portion of the Potomac River. They can be found in most of the tributaries between Great Falls and Colonial Beach and much of the mainstem between those two points. Over the last two years we’ve received numerous phone calls from people reporting the occurrence of snakeheads in the headwaters of many of the tributaries. As a result, we are currently surveying the upper reaches of some of our streams to determine the extent and usage of these areas by snakeheads.
What are some of the emerging environmental issues that should concern anyone who cares about the Potomac?
There are more than a few environmental issues that involve negative impacts on water quality and living resources in the Potomac River.
One problem that Maryland DNR is really trying hard to focus awareness on is the continued introduction of non-native species (both plant and animal) into our waterways and streams.
The northern snakehead situation highlights the problem these introductions can produce. Rusty crayfish, didymo, whirling disease and zebra mussels are just some of the other invasives that Maryland is currently dealing with.
Undesirable aquarium and pond plants like water hyacinth and water chestnut are also invasives that are commonly released by pond enthusiasts and can spread quickly in our waterways.
Anglers should become familiar with some of the non-native species listed on both the Maryland and Virginia Resource websites and report any sightings to the proper agency. If you are not sure of the identification of the plant or fish that you come across during your outing we can often identify the species from a good digital photograph.
How can someone who is new to fishing learn about the river?
One of the most important steps you need to take when you start fishing the Potomac is invest in a navigational chart (preferably waterproof). There are plenty of shallow areas, submerged obstructions and off-limits areas that are marked on these charts.
All too often we’ve come across someone who was not familiar with the Potomac and they’ve run aground because they thought they had plenty of water under their hull. You should be mindful of the tides too since they can often make a difference on where you want to fish.
Global Positioning Systems (GPS) are an easy way to access navigational charts and tide tables as well. We’ve been using a small, portable hand-held unit on our boat for years and I wouldn’t take to the water without one.
In addition to a navigational chart, there are various fishing maps that have been produced by individuals and fishing clubs in the area. A quick search on the internet will yield a variety of maps that would be useful.
Booking a trip with a local guide is always a great way to be introduced to the river and anglers can always call our office if they would like some information on fishing for specific species.
What are some of the basics? What do you need to understand about flows, temperatures and tides?
A lot of the rules that apply to inland fishing (flow and temperature) also applies to the tidal Potomac. Most fish will go deep when it’s too cold or too hot. Shallow water fishing is usually great in the spring and fall, especially in the evening.
Catfish often like to collect in deeper water at the mouth of creeks, but they can also be caught in the shallows when they feed in the evenings. Many fish like to feed on a moving tide, it just takes a while to pattern various species.
Since the Potomac is an ever-changing river, anglers need to be flexible and willing to try different techniques, areas and baits/lures.
We’ve seen people fly fishing the Potomac for bluegill, bass, striped bass, carp, shad (catch and release only) and a few adventurous folks have voiced their interest in trying their hand at fly fishing for northern snakehead.
Are there safety issues?
While the tidal Potomac can (and does) flood occasionally, the bigger problem during heavy rains is the turbidity of the water. Silt and sediment that is carried from the mountains and piedmont areas is carried downriver and collects in the relatively calmer tidal portion of the river. This turbidity takes a while to clear.
Often logs and other debris are carried along with the muddy water and can float just below the surface creating a real danger to anyone in a watercraft. It’s always a good idea to keep boat speeds down when these conditions occur.
During warmer months, severe thunderstorms can pop up unexpectantly on the river so it’s a good idea to keep an eye on the sky and check the weather before heading out for a fishing trip. Also, be mindful of boat wakes if you’re in a smaller craft such as a canoe or kayak.
Optimist or pessimist about the future health of the Potomac?
The Potomac is a wonderful river that provides a variety of angling opportunities from fly fishing to bow fishing. The future of the river depends on a heightened awareness by both the public and government officials on the vulnerability of the river to stormwater run off, erosion, point and non-point pollution, and the expansion of impervious surfaces.
Solutions to these problems aren’t always easy or clear-cut so it’s important for anyone who is interested in the health of the river to become involved in local conservation groups who work to improve water quality, habitat and access to the Potomac.
Mary thanks again for taking the time to talk with us.