The General Practitioner fly – forefather locked in place 95 million years ago – during the Upper Cretaceous period, when Triceratops, Tyrannosaurus, and Velociraptor roamed the earth. Early ancestors of the Atlantic salmon and steelhead have probably also been feeding on prawns like this one
The prawn they know so well
Pandalus Borealis – Known as the North Sea Shrimp, Northern Shrimp, or Greenland Shrimp – is the creature that comes to mind for most fly tiers when they’re tying a General Practitioner fly.
We often have multiple names for the things we cherish, and this sizable prawn is a favoured food source for both humans and Salmonidae.
This pink-hued prawn inhabits depths ranging from 20 to 1,330 meters (66 to 4,360 feet) in both the Atlantic and Pacific Oceans. It thrives in relatively cold waters, with temperatures ranging from 2 to 14 degrees Celsius (36 to 57 degrees Fahrenheit).
Both the Atlantic salmon and Steelhead are known to feed on these prawns, along with many other crustaceans.
Image courtesy of
Fish and Shrimp: A Favorite Menu for Atlantic Salmon
Atlantic Salmon have a strong preference for shrimp flies, as studies indicate that a significant portion of their diet consists of shrimp. In fact, there have been instances where a General Practitioner fly was mistaken for the real thing.
Revealing studies
Insightful research conducted by biologists Jacobsen, J. A., and Hansen, L. P. sheds light on the feeding habits of salmon in the North-East Atlantic. Their studies revealed that while shrimps constituted 95% of the prey in terms of numbers, they only contributed about 30% by weight.
Interestingly, the stomach content analysis showed that fish made up 66% of the weight, with a focus on mesopelagic fish Additionally, larger pelagic fish such as herring, blue whiting, and mackerel were also part of the salmon’s diet.
By weight, 66% of the stomach content was fish, particularly mesopelagic fish. Some larger pelagic fish such as herring, blue whiting, and mackerel were also part of the dies.
Overall, fish and crustaceans made up 96% of the weight of all prey consumed by salmon. However, the report also mentions a small percentage of bird remains found in salmon stomachs, indicating occasional predation on birds.
The menu card
Prawn Hypnosis
Prawns possess an irresistible allure for the Salmonidae family, , leading many salmon rivers worldwide to ban their use. Even the dried-up head or thorax of a prawn can elicit frenzied responses from salmon and trout, causing them to thrash through the surface on a scorching summer’s day. What exactly captivates them about prawns? Is it the way sunlight illuminates their texture, their distinctive silhouette, or perhaps their behavior in the water? It’s difficult to pinpoint, but prawns and shrimps, in their various forms, constitute vital food sources for salmon, eagerly sought after in both rivers and seas.
Above: Featured is an original 1980s Frances fly from the renowned fly-tying shop of the late Mr. Peter Dean. The Frances fly stands as an iconic and highly effective prawn imitation, alongside the General Practitioner fly.
The General Practitioner fly must have prawn imitations.
It’s widely recognized that prawn-fly patterns, such as the esteemed General Practitioner fly, exhibit varying degrees of effectiveness in different regions. British and Irish salmon, in particular, show a greater inclination towards prawn flies compared to those in Norway. Nevertheless, it’s challenging to determine whether most of our sub-flies are perceived by salmon as prawns or shrimps, as fly tiers often unintentionally incorporate the prawn theme into their work.
When Mr. Esmond Drury crafted his renowned General Practitioner fly, it’s likely that he had the Pandalus Borealis in mind. Salmon appear to readily identify this prawn imitation, likely due to its resemblance to the crustacean found in the Northern seas, which has likely been a part of the salmon’s diet for millions of years.
Modern research unequivocally demonstrates the significance of prawns or shrimps in the Atlantic salmon’s life cycle. This includes not only larger prawns like the Pandalus but also smaller crustaceans within the krill family.
As twilight descends and the world takes on hues of red and orange, there’s a magical transformation in the air. It’s during this enchanting hour that a prawn fly like the General Practitioner seems to come alive, drawing the attention of salmon with its vibrant colors and lifelike movement. However, it’s not just prawn flies that excel during this fine hour; all types of flies seem to perform better as nature transitions into darkness.
Salmon caught on a #4 General Practitioner fly.
The General Practitioner story
The General Practitioner fly, conceived by the late Mr. Esmond Drury in 1953, stands as a testament to his innovative prowess. Mr. Drury, also renowned for his creation of the famous Esmond Drury treble hook in 1948, designed this fly with a specific purpose in mind.
While fishing a distinct pool on the River Test near Romsey, Mr. Drury encountered overhanging bushes that made orthodox fishing techniques impractical. Recognizing the effectiveness of a prawn drifted downstream to entice salmon, he crafted a large imitation prawn suitable for this unique approach. Initially named the “GP” due to its predominant use of Golden Pheasant feathers, Mr. Drury later christened it the General Practitioner, a name that underscored its deadly effectiveness.
The original General Practitioner fly was tied on a very long shank #2 double hook. Mr. Drury also recommended tying smaller versions, especially for summer conditions or when salmon were more tentative in their response.
Colonel Esmond Drury, the mastermind behind the General Practitioner fly, is pictured here with a brace of salmon from the River Wye. Photo courtesy of Mr. Jan Johansson, featured in his remarkable book: “du underbare laxfluga.”
Tying the General Practitioner
Beware the Woodoo
When casting the General Practitioner fly, I’ve witnessed a remarkable phenomenon: seemingly disinterested fish suddenly electrified as if this fly were the one they had been eagerly awaiting. I’ve seen them dart toward the fly at full speed, only to halt abruptly upon reaching it, then hastily retreat to their hiding spots. This behavior, unique to the General Practitioner fly, is truly remarkable.
The General Practitioner fly can be scary.
Indeed, the General Practitioner fly can evoke a sense of unease. Its presence, along with other larger prawn flies, can sometimes have a negative impact on salmon. In low water conditions or when numerous fish are concentrated in a pool, I’ve observed salmon react with apprehension as the prawn fly approaches.
Personally, I prefer to tie the General Practitioner fly on double hooks sized #6 or #4. This gives the fly the right balance of strength and posture. I aim for the fly to drift towards the fish, ideally in a slightly sideways manner, presenting a natural and enticing allure.
Tying the General Practitioner fly (the Fishmadman way)
Mustad 80525BL is Probably one of the best if not the best double salmon hook in its class and the perfect choice for the General Practitioner fly. Make sure to find a uniform hook. The GP pattern does not take it easy with hooks that are unsymmetrical-this
a # 4 hook Add silver tag – Use red thread
Wind body of seals fur.
Tie in two Whiting Spey Hackles hot orange – ¾ of the way up the body and another feather at the top.
Run the two Spey hackles through the body. Secure with the silver tinsel – Pluck the fur out.
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