Egg Sucking Leech: A Deeper Look at a Controversial Fly

Take the IGFA’s marlin fly fishing guidelines as an example. These include trolling a baited lure until a marlin chases it, only to then rip it out of the marlin’s mouth to cast a fly at it instead. But wait — there’s more. If the boat’s not out of gear at the exact moment the fly cast is made, the fish “doesn’t count.”

Then there’s the hierarchy of “respectable gamefish.” In the fly fishing world, Atlantic salmon are usually highly regarded, whereas carp are scoffed at and labeled the poor man’s bonefish. More accurately, carp fishing was historically seen as the only available option to anglers who couldn’t afford to fish expensive, privately owned water.

Then there’s my personal favourite grey area in the fly fishing arena: fishing egg patterns for steelhead. As an angler who learned how to fish with a spinning rod and bait box, I never quite understood how fly-fishing had its own set of rules. I’d always been of the mindset that there was only one set of rules, and that they were found in the flimsy pages of the government’s annual angling synopsis.  

One can imagine my surprise when I finally made the decision to start fly fishing, only to face backlash for fishing an egg-sucking leech. Further adding to my confusion were the anglers who fished egg-sucking leeches, yet screamed sacrilege on anglers fishing a simple egg pattern. How did making the fly bigger by attaching a second piece of artificial bait make it any more ethical?

Yes, fly fishing to the non-fly fisher can be confusing.

Personally, the confusion began to clear as I gained confidence, experience, and a better understanding of the sport’s history.  Here are some eggs-for-thought for the recently converted fly fisher trying to find their way in our beautiful, yet perplexing, pastime.

Why Are Egg Patterns So Frowned Upon?

Depending on who you talk to, you’ll hear various thoughts and theories on the matter, but the argument almost always comes down to efficiency. Are we catching fish too easily? More importantly, are we catching too many?

It’s impossible to deny the efficiency of both dead-drifted and swung egg flies in certain steelhead rivers — though the logic behind this is puzzling. For starters, adult steelhead don’t need to eat during their freshwater migration and can even survive up to one year without food! Secondly, eggs can’t swim through the current, yet steelhead don’t seem fazed by the abnormal presentation of a swung egg fly. Many anglers believe this is an engrained habit from the juvenile phase, whereas others swear that the fish are feasting for caloric gain.

I remember hearing reports from upper river lodge owners about fish sitting below salmon redds, gulping down eggs as fast as they bounced by. The further upstream they were, the more honed in to eggs they became, much like a rainbow trout on the Henry’s Fork when the hatch is on. It’s this very reason bait works so well… and perhaps this is where the conflict stems. 

Longtime guide, former shop owner, and major band rep, Scott Baker McGarva, feels the controversy lays within the angler’s own sense of personal fulfillment. He believes dead-drifting egg flies may bring the fly-fisher back to his or her days of bait fishing — a method many of these same anglers come to identify as unskillful.  

For some anglers it’s not so much the fly, rather the method that is unappealing. For me, years of watching a baited dink-float left me completely disinterested in staring at a bobber of any variety (hopper/droppers included), so swinging streamers seemed to be the natural progression.  

With swung flies, it was the feel of my rod unexpectedly lurching in my hands; a jolt reaction opposed to a visual one. Simply put, it was more exciting. Like walking through a haunted house knowing the actors are about to jump out at you — it’s just not as fun if you see them coming. But I didn’t make the switch because of ethics; I made the switch because I wanted the exhileration.

But for most people, it is simply the fact that any fly with an egg tied onto it is just too damn productive. Anglers fishing dead-drifted and swung eggs have been known to catch up to twenty fish a day! Honestly, this is just too many fish being handled in a mandatory catch and release fishery.  

A caught and released steelhead means there is a 3-10% chance of mortality for that fish. Selfishly, I’m willing to accept that risk on a fish or two caught every other day. But when such figures are calculated for twenty released fish, it is almost a guarantee that a fish is going to die. That just seems even more insensitive in an already relatively selfish scenario.  

The figures can be argued and I suppose it could be said that the angler catching twenty fish a day over the space of their once-a-year, week-long vacation is no more damaging than the local fish-bum or guide landing two fish per day over a three month season.  

That said, this sort of number-mongering can occur with any method of fishing: bait, spoons, eggs, even a size 10 mayfly. As long as the hook isn’t set in a way that the fish will swallow it, it seems all is fair in love and war, yet one would hope that the angler knows within themselves when enough is enough.

Egg-Sucking Leeches

Contrary to popular belief, flies with egg heads have been around for close to 200 years. This makes it difficult to validate arguments that we shouldn’t fish egg-suckers because they’re not traditional. Flies like the Dallas, Toppy, and Beauly Snow flies were finished with tufts (technically termed ruffs) of red, orange, yellow and green mohair — essentially turning beautiful classic flies into really expensive, time-consuming egg-suckers. Even leech flies have been tied as early as the 1700’s, with The Horse Leech Fly from Brookes’ ‘Art of Angling’ mentioned in 1740. Classic fly tyer, Dave Carne, adds that it’s important to note that most of the bright-head flies were primarily used as spring patterns. 

The flies were meant for Atlantic salmon in the snowmelt of early spring, when the fish were kelts and biologically different from when they first entered the river. The ruffs were said to be tied into the fly to attract the fish’s attention, however they just so happened to be used when the winter spawn’s eggs were washing downstream.  

I reached out to fly-tier extraordinaire, Stuart Foxall, to learn more about the history of these flies. Stuart believes that the tufts did indeed come in handy when used in fisheries with spring kelts. Unlike Pacific salmon, Atlantic salmon don’t die after spawning, but they do undergo major physical changes. Darkened flesh, leaner bodies, and hooked kypes are some of the more obvious transformations.  

Stuart believes one explanation for the tufts is that they helped stick to the kelt’s teeth. Additionally, salmon flies were expensive and time-consuming, and the tufts made the fly more durable. However, Stuart was quick to confirm that there would have been many eggs washing downstream at that time of year.  

He adds, “So did these flies work so well and stand the test of time because fish thought they looked like an egg-sucking leech?  Yes I think they did… probably.  But I don’t think that was the reason they were tied that way.”

Stuart is the first to admit that the egg-sucking leech is one of the most productive flies on many interior steelhead rivers, but he is just as quick to admit that he won’t be caught dead fishing an egg if it doesn’t have some sort of streamer affixed to it.  

“I think for my own state of mind and perhaps for when others see us fishing — it’s not like I want to be seen with a bead on my line—I think a fly tied with mobile materials at the back show we are trying to attract fish by movement during the swing. And I think it is the movement that is the main attraction here.”

He clarified that because the fish weren’t swallowing the fly, he doubted they were specifically targeting the fluorescent egg up front.

This reminded me of my days fishing in Alaska, where often a single egg is fished for trout and grayling dialled into salmon eggs. Depending on how the egg is rigged, it can be deadly to a fish that swallows it.  

Alaska is no stranger to fishing eggs. In fact, it is here where the original egg-sucking leech fly was conceived. Around 1984, the late angler and shop owner, Will Bauer, popularised the iconic fly. Though it seemed to be built around Russell Blessing’s 1967 wooly bugger, the egg-sucking leech simply added a wrap of bright chenille, giving the fly more visibility. 

It took its time migrating to Canada. Previously, anglers from the 1970’s fished with waked deer-hair flies, traditional Spey flies, October Caddis, caddis pupae, and stoneflies — all flies deemed “sporting”. 

Baker-McGarva remembers when the egg-sucking leech first reared its head on the Skeena river’s more “trouty” tributaries. The results were game-changing. He has a valid point that, like trout, steelhead (which are ocean-run rainbow trout) also become selective and focused onto specific hatches.

He’s also quick to point out that, in his years, he’s seen some of the best intentioned anti-egg anglers fishing eggs without necessarily knowing they were doing so. He uses one of the sport’s most traditional flies, the Green Butt Skunk, as an example.  The small splash of green at the rear of the fly is thought to be an attention grabber, but it’s just as likely to be imitating an egg. Equally as unassuming are various small soft-hackle emerger patterns tied in peach or green — also easily confused as an egg — especially when dead-drifted. Imagine that! Attempting to be a purist and fishing a glo-bug without even knowing it!

Professionally, Scott feels such numbers of fish ruin anglers and create unrealistic expectations, however, the pressure of getting clients into fish often means that eggs are a necessary evil. He recalls that even when guides suggested other flies, clients refused to fish any other way.  

Do Leeches Even Eat Eggs?

I asked Professor, David Barton, of the University of Waterloo if this is something he’d encountered during his studying of leeches.  

“I have never seen a leech eating a salmon egg, but it is certainly possible. As you are aware, some leeches are obligate blood-feeders but most species prey on other invertebrates. Some swallow their prey whole.  If the prey is large relative to the leech, swallowing can take some time.  Others have an extensible proboscis and saliva containing digestive enzymes, so they latch on and suck out the tissues as a semi-digested fluid. This too can take a bit of time, so it is conceivable that a leech could attack a salmonid egg .  If the leech were dislodged from the bottom before completely swallowing or draining that egg, there would be an “egg-sucking leech” frantically trying to reach the bottom of the river again.”

He continued.

“Is this likely to happen?  My suspicion is that it is very unlikely.  Leeches are seldom abundant where salmon spawn, and the frequency of predatory leeches in the water column of any body of water is very small. Blood-feeding leeches will swim actively toward sources of food, but the predatory ones are much more circumspect.”

His notes brought me back to something interesting Scott had mentioned. Over the years Scott has seen a surprising amount of juvenile lamprey eels in steelhead rivers. This sparked my curiosity. Perhaps the egg-sucking leech was a very lifelike representation of an egg-eating lamprey? It’s something I don’t have any proof of at this time.

So it’s easy to understand the varying viewpoints of this hot topic, but I maintain that the decisions we make as outdoorsmen and women ultimately come down to individual preference, morals, and education. 

Personally, I agree with Scott that angling methods are based around our own fulfilment.  I spent twenty years steelheading with the goal of stretching my day out as long as possible — long enough to encompass more than just the fish. The fall leaves, meditative hum of the water, bald-eagles spying my every move… fishing for me was more than just “catching fish”. One, two, even zero fish caught over the space of an eight hour day was okay with me. At that stage of my life I had nothing but time, so I lived to fish new water with new fly patterns. It was the satisfaction of experimentation that was so fulfilling.

Now, as a mom and business owner, I simply don’t have the time to play around in runs that may or may not hold fish, or fish with flies that may or may not catch them. I prefer to entertain my daughter with nature rather than television, and she loves when a fish is caught. So these days, I march straight to the runs I know hold fish, put on an egg-sucking leech that I know will catch one, smile with my kiddo when the fish splashes us during its release, and then head back home to do other things.  

This new time restraint makes me feel silly for all the years I judged anglers who opted to take the “quick and easy” rather than the more dimensional route I felt they owed the sport. You just never know a person’s reasons for the decisions they make — more importantly, as long as no one is getting hurt or breaking the law, such decisions are really no one else’s business.

Fly fishing may have some crazy ideas and standards, but at the end of the day—if it comes down to personal fulfillment—I have faith that most of us find satisfaction in ethical entertainment. And that means it’s up to you to decide just how far you’re willing to take it.