Slow Prey

Bill Mitchell advocates matching the hatch for fussy flats dwellers

Many inshore fish species eat slow prey. These include iconic tropical fly-fishing targets such as bastards (FL#30, #88) and tuskfish (FL#83) but also bread and butter species like bream. When it comes to slow prey, saltwater anglers have relied for too long on limited knowledge about fly choice and presentation. Refusals have only led to lame excuses for our lack of success. For freshwater anglers, matching the hatch is more than a nod to tradition. They use prey image effectively. Streamcraft includes knowledge of local aquatic and terrestrial food items. Saltwater anglers on the other hand are more likely to look in their fly box for inspiration than search along a mangrove edge or in a seagrass patch. This needs to change, especially for slow prey. In my quest to find a fly attractive to members of the family Haemulidae, which includes all manner of bastards, and after a summer of experimentation with fly choice, I began to think more deeply about what was on their daily menu and chased up articles on their feeding habits. Science from all over the world revealed they had a steady diet of small spineless critters. Resources from seagrass and reef flat habitats provided half their diet. This included filter feeding bivalves (cockles, clams, mussels) and grazing gastropods (sea- snails, periwinkles, rock snails). My own experience of local slow predators like blackspot tuskfish (which we normally target with crab or shrimp flies) was that stomach contents included lots of sea snail shell fragments. It makes a lot of sense when you watch fish like bastards and tuskies feeding. They drift quite slowly, inclined in a tailing aspect, scanning the bottom. They have big eyes to pick out small detail and motion. When they see prey they fin down to the bottom to eat. At times they corkscrew in places to dig out prey. They have gripping teeth with pharyngeal crushers behind to grind. These are useful given slow prey are also often hard shelled. Most importantly, they take their time. They browse and graze, and like fussy children, can be infuriating slow, picky eaters. It also makes a lot of sense that they target prey that can’t escape. Slow prey. FORM & FUNCTION Some of the success of crab flies might be their obvious similarity to bivalves, for which a permit’s mouth looks perfectly shaped to eat, with crushing plates behind. Science on the genus Trachinotus (permit) showed adult diet consisted mainly of bivalve molluscs but they are opportunistic feeders on a range of benthic invertebrates. Could it be that our flies are working at times because they are seen as slow prey — by virtue of appearance or presentation or both? Del Brown’s infamous ‘do nothing retrieve’, which accounted for 500 permit, could equally be called the bivalve retrieve. Ever seen a clam try to outrun a fish? Was Brown’s retrieve an each-way-bet manoeuvre that turned slow prey into even slower prey? There are of course a myriad of approaches for fish like permit and it will never be a ‘one size fits all’ solution. But it doesn’t hurt to think aloud about such things. Responding to general ‘aspects’ or ‘categories’ (fish, shrimp, crab, worm) allows fish to include a wide variety of prey in their diet. Prey recognition, prey detection and prey image theories all reinforce the importance of form and motion. Get both right and it triggers ‘sign stimulus’ behaviour, or what we call ‘the eat’. Our job is made easier where different types of prey have shared prey image triggers including those related to form and motion. Crab flies are a good example. For years people avoided them because they thought the ‘no retrieve’ was the only, somewhat intimidating, option when in fact a range of presentations and retrieves is possible with that style of fly. A fundamental characteristic of an effective each-way-bet (FL#75) is that it can be changed-up from a static to dynamic retrieve if need be. It can look and act like more than one type of prey. So how about some examples? Let’s work our way through some slow prey. SNAIL’S PACE Trout anglers have been using gastropod flies for a good while. Watson (FL#75) made observations that are exactly in line with my thinking: ‘At times an obvious insect can mask another, more important hatch.’ In his case in point, caddis and duns looked like the culprit when in fact snails were the order of the day. He noted there are many patterns for targeting snail feeders, but he prefers more realism because ‘the trout know the snails can’t escape and have plenty of time to pick a fake.’ The need for realism in slow prey is important. Even further back, Wolf (FL#14) was talking up snail patterns. He argued their utility for tailing trout, where the fly is moved small distances, very slowly. The more I read, the more I am encouraged to break out of my jingoistic patriotism towards shrimps and crabs, or at least to expand their potential to include even slower prey. I found ample freshwater patterns. How hard could it be to adapt some of these patterns or at least the idea of these patterns? MOONS & MOLES In 1932 William Beebe said, “If we live out our span of life on earth without ever knowing a crab intimately we have missed a good friendship.” Crabs are indeed good friends to the saltwater fly angler. Decapods (meaning ten feet) are exceptional slow prey. They include true and false crabs. True crabs are those we know well: moons, muds, swimmers, fiddlers, soldiers and ghosts. Increasingly, saltwater fly anglers are becoming more adept at identifying and imitating specific decapods predated on by our iconic species. A good example is the moon crab (Matutidae) — a prolific prey image used in east and west coast permit fisheries. But what of the other decapods? We know less about false crabs but they may be equally important to us. They include what Americans call mole crabs and we call sand crabs (Albuneidae). They are widely distributed in sub-tropical and tropical parts of Australia. We don’t see them often because of their burrowing habit. American anglers use mole crab (aka sand flea) patterns for striped bass in the Atlantic states through to inshore fish like pompano and redfish across the Gulf states from Florida to Texas. These patterns are virtually unknown here but given the parallels with our fish and fishery, my guess is that we should be trying them. It is also fortuitous that detritivorous hermit crabs (Diogenidae) tenant shells once inhabited by gastropods. Also false crabs, hermit crabs move a little faster than snails, but they aren’t going to set the world on fire either. A true each-way-bet for the fish – a lucky dip in a shell. BIVALVES – SURELY NOT There are patterns that mimic bivalves. And why not, they are up there as a substantial diet item for most fish we chase. Look at the hilariously named ‘clam before the storm’ (Matthews). I’m not advocating that we actively (or inactively as the case may be) fish clam or oyster patterns, just be aware of how they increase prey image options for our flies. DON’T FORGET WORMS And what about the annelids? Just a fancy name for worms, these are another regular food source for seagrass meadow and reef flats dwellers. Science tells us that 15% of a Gulf of Carpentaria bastard’s diet is worms. Worm flies abound in freshwater fishing. The San Juan worm (FL#49) and Woolly Worms (FL#49) potentially lend themselves to saltwater adaptation. Floating or subsurface worms such as palolo and other polychaete worms (Eunicidae) are common in US tarpon fishing and more recently for milkfish here in Australia (FL#51, #65, #74) but what about those that sink? Hammer’s Worm recently turned Christmas Island bonefish flies on their head — or did it? For years I’ve thought the wispy wing of a CXI Special (FL#46) or Gotcha, George Bush or Chilli Pepper (FL#62) might well appear as a tasty worm to a bonefish and I’m pretty sure I didn’t invent that particular theory. What we see as a shrimp or baitfish pattern, fish may see as a worm. Once again we see the potential for an unintentional each-way-bet making slower prey. Hammer’s fly validated that bonefish eat worms. Many tried and true bonefish patterns take an each-way-bet between worm, shrimp and small fish. And it isn’t limited to exotics: many local inshore fish have been taken on homemade blood and beach worm patterns. SLOW FLY DESIGN Whenever I look in carp fly boxes I see flats boxes rendered in miniature. Many of the best carp flies are hybrids that combine a number of notorious triggers for carp. They include elements of worm, gastropod and other bottom dwellers. Flies like Parmigiani’s Sunbaker (FL#85) tick all the boxes of a slow prey fly. Upsize that fly and change up the colour scheme and you have a great example of cross-fertilisation of ideas. It could easily pass as a gastropod or small crustacean. It is important to think about local habitat. This will determine prey species and relevant permutations of size, colour etc. You can match the hatch by adapting the colour and contrast on existing patterns. You can downsize if chasing the smaller predators like bream, or upsize if need be. Natural materials will offer movement that helps a slow prey fly move without being moved. Think marabou, zonker, fur and hackle. Artificial materials aren’t generally known for their movement, but some are very useful, including craft fur, EP fibres, chenille, hackle wraps, brushes and rubber legs. Good flats flies already effectively combine naturals and artificials. Building a good profile also helps flies tick multiple prey image boxes. While we all seek out the latest and greatest fly, many older patterns are excellent. FISHING SLOW PREY How then do we fish slow prey? Well obviously there are some keys that we already know. Slow predators hover and inspect and are prone to being spooked by sudden movements, heavy splashes, plops etc. They also tend to get a good look at the fly. A friend says the trick with these fish is to show them the fly but not let them get a good look at it. This is achievable if what they see triggers the instinctive reaction to eat. Slow prey flies are mostly fished on the bottom, so fish need to be led to allow time for the fly to sink and settle, often on a longish fluorocarbon leader with light tippet (14–16 lb). It will also help to disguise the presentation if it is a little further away, though sometimes a shot right on the feeding box is needed for tailing fish. Often the fish are feeding into the tidal flow, and current and the materials themselves ought to give the fly enough movement without the need for too much marionette work through the fly line. Subtle bumps and nudges are the go. If the fish loses interest, a short sharp strip will turn the fly into something different. At times, casting up-current and slow-swinging the fly will be the ticket. Make the cast, take the slack out of the line and then start the fishing. This is all really just food for thought. Take note of what’s on your local flat and what the fish are eating. Think about how form and motion coalesce in your fly choice. Maybe those filter feeding bivalves, detritivorous decapods, squirmy worms and grazing gastropods will start finding their way into saltwater fly boxes in the same way a canny trout angler will have a few unconventional patterns in the box. Anyway, you won’t really know whether it works until you try it.

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