Maryland Muskie History and Management

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Maryland’s only muskie population exists in the freshwater Potomac River. This relatively new fishery is maintained entirely through natural reproduction. Favorable habitat conditions and natural reproduction has allowed the population to slowly expand its range in the river system. Muskies have been collected during routine fishery surveys from below Great Falls (Washington D.C.) to Spring Gap (Allegheny County, MD), with the highest densities and most popular angling opportunities found throughout the Washington County section of the river (Dam 3 to Hancock).


History

From 1989-2005 the Maryland Department of Natural Resources Freshwater Fisheries Program stocked hybrid tiger muskie into the non-tidal Potomac to provide anglers with additional sportfishing opportunities. Stocking efforts were reduced substantially from 2000–2004, and ceased in 2005 due to the expansion and stability of a “true” muskie population. Because they are sterile, current and future tiger muskie encounters in the Potomac River are unlikely.

State Record MuskieTrue muskie were first documented in 1996 when a 45 inch, 27.8-pound fish was caught and became the first state record true muskie for Maryland. This fish was estimated to be at least ten years old by scale analysis. Later that year a single juvenile was collected during a fall electrofishing survey. By 2001, twenty-eight muskie had been collected representing multiple year classes, suggesting that this species was naturally reproducing in the Potomac River. The origin of the Potomac River muskie population remains unknown. Because of size differences and separate rearing areas, it is unlikely that pure strain muskie were mixed in with loads of tiger muskie. The age of the 1996 state record fish also suggests that this fish may have been present in the Potomac prior to any tiger muskie stocking efforts, which began in 1989.

The most recent Maryland state record muskie was caught by Kyle Mullenix of Hagerstown caught the 33-pound, 49-inch long record muskie on March 2, 2022 along the banks of the upper Potomac River.

The catch surpassed the previous Maryland state record held also by a Washington County resident, Tessa Cosens, whose catch tipped the scales at 32.5 pounds. ​


Tagging Program

An on-going tagging project to gain insight on exploitation, movement and growth was initiated in 1997. A single yellow dart tag is applied using an applicator needle on the fish’s left side hooking into the interneural bones. Each tag has a unique four-digit number that becomes the only identifier for that specific fish. Tags are visible on the leading edge of the dorsal fin of the fish’s left side but often get obstructed by algal growth. The algae can be easily scraped free to reveal the four-digit number.

 
The most important information to record following the capture of a tagged fish are: the four digit tag number, date caught, location of capture (general), length (to the nearest ½”), and whether the fish was kept or released successfully.

All tagged fish can be reported by calling 301-898-5443, emailing josh.henesy@maryland.gov, or by recording the information on the voluntary creel diary App or form.

To date, a total of 992 Potomac River muskellunge have been tagged with 461 recaptures for an overall (angling and electrofishing) recapture rate of 46.5%.​ Less than five percent of tagged muskie are directly harvested which indicates that most anglers voluntarily release this species to be caught again. The longest traveled distance documented for a tagged muskie was roughly 70 river miles.

Radio Telemetry Project

From 2018-2020, the Maryland Department of Natural Resources Freshwater Fisheries Program documented seasonal movement patterns and habitat preferences, including the reliance and usage of thermal refugia by Muskellunge during summer months.  Additionally, we determined the thermal trigger (mainstem river temperatures) that initiated movements and occupancy into refuge habitats.  A manuscript titled, “Seasonal Movement Patterns and Summertime Use of Thermal Refuge Areas by Muskellunge in the Nontidal Potomac River, Maryland,” has been published with the North American Journal of Fisheries Management. 

A mean annual mortality rate of 19% (95% CI: 10-27%), which ranged widely from 8-32%, was determined throughout the course of this study (2018-2022). Interestingly, spring (50%) and summer (50%) represented the only seasons where mortality occurred. The mean annual recapture rate reported by anglers was 25% (95% CI: 22-28%), which is largely underestimated based on results from a post-card survey that was conducted to estimate angler participation.  These data suggest low participation from our constituents (21%). To date, only two captures during thermally stressful conditions have been reported, despite personal observations of high angling effort.  

Our initial goal to estimate summertime exploitation was to monitor angler recaptures during summer months.  Due to the extreme lack of participation and extremely small sample size acquired, a mark-recapture population estimate was conducted during the Spring of 2022.  Estimates of this fishery suggest a healthy population with a robust size distribution, (7-11 Muskellunge per river mile ≥ 30”).  These data will be collected every five years to monitor changes in this resource.  
Results from this study provides direct evidence of Muskellunge reliance and occupancy on thermal refugia during periods of thermal stress in a southern riverine environment.  It is quite possible that Muskellunge population size, growth, and mortality may be limited to thermal refuge availability in southern rivers.  A need to better understand summertime angling from these environments still exists, and further research is encouraged.  We would like to extend our great appreciation to Muskies Inc. for providing the necessary funding to investigate and document this novel research.  This information will help managers identify whether outreach or regulatory actions are needed to sustain trophy fisheries.

Voluntary Creel Survey

In 2009 the Freshwater Fisheries Program initiated a volunteer-based creel survey program to aid in monitoring the size distribution and relative abundance of Potomac River muskie. Volunteer-based surveys are a common tool used in muskie management throughout North America. Data collected from the diary program has proven to be the most efficient and beneficial tool for tracking changes in the fishery through time. For example, the average electrofishing catch of muskie is 34 fish per year, whereas the average angling catch reported through the creel diary program is 129​ fish per year.

Participating anglers record the date, the number of anglers targeting muskie, the general location that they are fishing, duration of the trip, total catch (including trips where no fish were caught) and the tag numbers from any tagged fish caught. Traditionally, a paper log was kept by each participant and submitted at the end of each calendar year. Starting in 2019, anglers began recording their creel information electronically using the online reporting system. Each submittal will be kept confidential and the submitter will be provided (emailed) with a PDF summary of their catch related information as well as a yearly summary from all of the pooled data. In addition, all participants will be entered into an annual prize lottery, receive a custom Maryland Muskie hat and sticker, and be actively involved in the management/data collection of Potomac River muskie. A summary of the 2020 Volunteer Angler Survey Summary can be found here.

AccessDNR

​The department's app (found on both iTunes and Android Stores) contains great tools and information for hunters, anglers and outdoor enthusiasts. It also provides quick access to the Volunteer Angler Surveys for many different species. 

Once you download the app, open it up to the main screen. Select the "Fishing" button at the bottom (as highlighted in the image on the left below). Now, select the "Volunteer Angler Survey" button (as highlighted in the image on the right below) to go to the Volunteer Angler Survey page. You will now see all of the surveys which are available for many different species. These survey's allow the department's biologists to collect data that identifies trends in catch quantities and sizes as well as a way to identify any water quality issues and track tagged fish.

AccessDNR_Main.jpg  AccessDNR_Fish.jpg 

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