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"Blushing is the most peculiar and most human of all expressions." Maybe so, but that didn't stop this gorgeous wild rainbow trout from showing its summer blush (after putting up one amazing fight -- a few cicadas all summer make for some healthy fish I guess). 

[houseofliao]

Life as a trout bum - group of us came upon this little stretch of#water, no one saw any rises or topwater activity, and I was the only one pumped up (and no one else knew why). Someone picked up a stone – who knows for what, but I presumed to skip or toss in – and I threw him a fierce glare. Then they all knew why. Oh, and then I pulled out some gorgeous wild rainbows from the far bank on dry fly 🙌

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CPR (catch-photo-release) life.

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"Live in the sunshine, swim the sea, drink the wild air." Emerson

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What Are the Best Rapala Lures to Start With?

It’s been over 80 years since a Finnish fisherman – tired of baiting hooks and observant of the fact that fish seemed to target minnows swimming off-center – first carved his first cork minnow imitation. As legend has it, he embellished his design using foil from a candy bar and melted photographic films, producing a lure that at times caught over 500 lbs of fish a day. Decades later, Lauri Rapala’s lures have retained their reputation as one of the most noted and consistent fish catchers within the angling community.

Making heads and tails of the many lure options, however, can be daunting for the new and transitioning angler. This is not an issue with Rapala in particular, but one that arises from the more general industry trend towards an ever-increasing number of different lure types/sizes/colors/options. It’s a good problem to have on balance; who can argue with choices? However, too many can also cause the pendulum can swing the other way towards confusion or ambiguity. In an effort to help the uninitiated angler navigate this landscape, yours truly turned to the bedrock of crowdsourced information: Google. While it doesn’t always know best, the search engine has an obvious track record for pulling relevant information from a broad range of sources that represents the opinions and experience of many individuals – a feature that is paramount to understanding choices when it comes to something as a subjective and empiric as lures (no one’s going to do a study or side-by-side trial of different tackle, after all). While lure selection is personal and based on confidence to some degree, I sought the unique insight from crowdsourced opinion and experience. The nitty gritty of the approach: using a search algorithm, I generated code and pulled data from the top queries for “best bass lures”, “best trout lures” and “best Rapala lures”, combining the results into an aggregate list. I excluded entries that focused on live bait, or in the case of trout lures, flies and fly angling. I pulled text and content using a web crawler and cross-ranked the results, giving priority to reputable sources (established angling sites rather than personal blogs or fishing forums). Finally, I assigned priority to the Rapala lures based on whether they were listed on the overall “best lures” lists and/or the “best Rapala lures” list. The result was that two lures “floated” to the top of the list (see what I did there?):

Original Floating (image from Rapala.com)– “the one that started it all”, this bait was by and far the top-rated/top- reviewed lure. Anglers frequently commented on its erratic motion and buoyancy, both features of its balsa wood construction, with the former allowing for off-center movement and the latter allowing for both surface and sub-surface presentations as a twitch bait or shallow runner.

Shad Rap (image from Rapala.com) – a close second, the Shad Rap seemed to be a favorite among reviewers, forum contributors and anglers for producing consistently.

Advice on the different sizes and colors varied – perhaps predictably, and appropriately, among different geographic locations. Other lures – e.g., jointed versions, Husky jerks – also received very favorable comments and could be prime choices for anglers more experienced with the brand and nuances between lure variants. However, in choosing foundational or first Rapala lures, the data and opinion from my approach seems clear: it’s hard to go wrong with the Original Floating or Shad Rap. 

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Of the many people, things & opportunities for which I'm thankful, the chance to get into some early spring and late fall fishing are definitely among them.

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Good Catch-and-Release Practices: Keeping Fish in the Water

The practice of “catch-and-release” is widely synonymous with conservation-minded angling. Many trout and bass anglers whom practice it identify with the desire to be environmentally conscious and aware about the need for fishery and ecosystem preservation.

While laudable as a philosophy, however, there are persistent issue with actual catch-and-release practices. One notable issue -- but one that is often discussed out of strongly held opinions, rather than data -- is how long anglers ought to keep fish out of the water before between catch and release (for hook removal, pictures, measurement or weights, etc). 

This matters because, perhaps unsurprisingly, one of the major determinants how well or poorly fish do after release is out-of-water time (i.e., “air exposure”). Beyond the stress of actually angling (bringing the fish in), which is a topic for another post, the additional stress caused by air exposure can adversely affect fish. 

The general rule is almost too obvious to state: the more quickly one releases fish back into the water, the better. However, specific information (e.g., how long can a fish be safely kept out of water, what happens if they aren’t) is both less intuitive and more actionable. Also, between new technology (portable chest- or head-mounted video), dissemination outlets (youtube, snapchat, instagram) and other trends, there is a growing list of new reasons/explanations for why anglers keep fish out of the water. Given this, it’s hard to argue that as conscious anglers, we should ensure that our catch-and-release ethos matches the reality of how we’re releasing.  It would be a shame to inadvertently harm the fisheries we’re trying to preserve. So what does the data say? First, a bit of framework:

Researchers often study both lethal (fish mortality) and sub-lethal (stress, impact of reproductivity, recovery time, etc) effects from catch-and-release fishing

Blood analysis is the most common method for measuring fish stress

a “stress response” is measured by looking at cortisol (a stress hormone in the blood), glucose (aka, “blood sugar”), and lactate (a biochemical byproduct that suggests metabolic strain; think about the “lactic acid” that builds up in your muscles after a hard workout)

cardiac responses -- what angling and handling does to affect fish heart rate and circulation -- is also sometimes used to evaluate adverse effects

Air exposure -- on the order of seconds and minutes -- impacts trout physiology.  In a study evaluating the effects of angling (fighting the fish) and out-of-water handling on rainbow trout, biologists found that:

Independent of being caught, survival dropped by 26% (from 88% to 62%) when fish were exposed to air for 30 seconds

Survival fell an additional 34% (from 62% to 28%) after 60 seconds of air exposure

Blood analyses showed that out-of-water time causes a stress response among fish that could affect survival during the recovery period

In a simulated experiment and analysis of air exposure on swimming performance among brook brout:

Fish exposed to 60 seconds of out-of-water time had no decrease in swimming performance

However, trout exposed to 120 seconds of out-of-water time saw their swimming performance decrease by 75%

no fish mortality observed after simulating angling and air exposure

decreased swimming performance could increase vulnerability to predators and surrounding environment

Air exposure -- on the order of seconds and minutes -- impacts bass physiology.  In a study of hooking injury and mortality from angling among Rock Bass (Ambloplites rupestris), researchers captured fish using worms and jigs and evaluated the effect of air exposure on fish physiology. Their findings:

Fish caught on barbless hooks were released after an average of 20 seconds of air exposure, while those with barbed hooks required >40 seconds to release due to difficulty with removing hook. 

Fish who were subjected to 30 seconds of angling, followed by 30-180 seconds of air exposure, suffered from heart problems (technically bradyarrhythmias and changes in cardiac output). 

Fish exposed to 30 seconds of air required 2 hours for fully recovered; those exposed to 180 seconds of air required 4 hours.

In another study, this one aimed at understanding the effect of air exposure on Largemouth Bass (Micropterus salmoides), biologists caught fish using standard line-and-hook angling techniques, exposed them to air for varying periods of time, and used external monitoring and blood samples to measure changes in fish biology and equilibrium. Among other things, the group found that:

Compared to those exposed to air for >10 min, fish exposed for shorter periods of time (<3 min) had significantly lower serum glucose levels and more quickly regained equilibrium after release. 

Fish exposed to air for long periods of time exhibited “behavioral impairments and remained close to the release site longer than those exposed for short periods.”

No fish mortality was observed in the 5 days following release 

The Take-Aways & Lessons:

When it comes to bass and air exposure, seconds and minutes matter (even the difference between 20 seconds and 1 minute)

even if not in terms of mortality, out-of-water time can affect behavioral patterns and recovery time (and may also affect other “sub-lethal” processes like reproductivity, predation, swimming performance, etc). 

for example, the rainbow trout study above suggests that keeping a rainbow out of the water for 1 minute can cause it to be be 1/4 as likely to survive (and that’s not even accounting for other issues such as bleeding, deep hooking, etc)

Because both trout and bass can be adversely affected by just an additional 30-60 seconds of the water, anything an angler can do to minimize air exposure is critical

consider barbless hooks to more quickly unhook fish (though in fairness, the efficacy is contested by some)

similarly, use pliers or other tools as a general practice to more quickly remove hooks

when possible, unhook fish in the water

keep fish in water as long as possible during the handling process (e.g. until cameras, etc are ready to go)

consider using underwater camera shots 

While not comprehensive (fish stress is affected by the actual exertion during the fight, the surrounding temps and conditions, etc), the studies above underscore the importance of keeping fish in the water.  One final note: though the existing data provides helpful insight for catch-and-release anglers, the information can also be useful at times for anglers planning to harvest fish (e.g., if a fish doesn’t meet slot requirements and must be released).

[houseofliao]

Why the Age of Your Lake Matters

When it comes to lake fishing, there is no shortage of discussion about fishing conditions and the “productivity” of different waters -- lakes that are fished out, lakes that inherently hold no fish; lakes that are difficult to navigate due to heavy weeds, etc. 

These are good discussions because (obviously) there are many factors between casting and catching. However, although most anglers have encountered issues with water clarity (ever argued with friends about the best color lure and hooks for different water clarity and stain?) and plant life (snags, anyone?), far fewer have probably thought directly about what causes them: the age of lakes. 

How can an understanding of lake age help anglers? First, some biology (which I’ll try to keep to a minimum!). As a lake ages, it produces different amounts of biologically important nutrients -- such as Nitrogen and Phosphorus -- that very literally give life to plants and animals in the food chain. These nutrients also happen to be the “limiting resources” in standing bodies of waters like lakes, meaning that more nutrients leads to more plant growth, which leads to more animal life (called “higher trophic levels”; see my post about the food chain here). Bottom Line: if nutrients lead to healthy fish and fishing, then it’s important to understand the fundamental “productivity” of lakes. 

We can think of lake productivity through “trophic class” (from the Greek τροφή, which denotes food or feeding) ,and lake fisherman should understand 4 basic trophic classes:

Oligotrophic - low productivity due to low nutrient content; this leads to low algal growth and clear water; as a result, the bottom waters tend to have ample oxygen and supports many fish species, including those that require cold and well-oxygenated water (e.g., trout); often have rocky bottoms

Mesotrophic - intermediate productivity due to a medium level of nutrients and plant life; in general have either submerged or emergent weeds and aquatic plants; tend to stratify (unlike oligotrophic lakes)

Eutrophic - high productivity from rich, or even excessive, nutrients; as a result, these lakes can support abundant plant and animal life; tend to be dominated by aquatic plants (lead to clearer water) or algae (leading to darker water); can lead to an excessive “algae bloom” that causes a fish kill; often have silty bottoms

Hypereutrophic - very high productivity; often have frequent and severe algal blooms; leads to low water transparency (e.g., visibility <3 feet); this can also create ‘dead zones’ where there is little life because of reduced oxygen levels

Bottom Line: as lakes age, they pick up sediment and plant life, which change the oxygen and nutrient dynamics (and therefore, fishing)

Anglers who’ve fished lakes for a while can probably close their eyes and pretty quickly think of lakes that fit into these different classes (those blessed with vibrant local lakes may even fish a few lakes in each of these classes). But for those new to lake fishing, or those exploring new water, this classification system can be extremely helpful for a few reasons:

Lakes of different trophic classes hold different species of game fish. Though this sounds obvious, it can help set expectations, avoid use of inappropriate line/rod-reel combos, and improve lure selection (in other words, it can help increase the likelihood that you’ll have a good way on the water, however you define it!). In general: Oligotrophic lakes tend to hold healthy populations of “cold water” species such as lake trout or whitefish (and sometimes, small walleye populations) Mesotrophic lakes tend to hold healthy walleye populations, along with perch, pike, muskellunge, smallmouth bass Eutrophic lakes tend to have healthy populations of largemouth bass, particularly in the early and middle eutrophic stages; as water becomes more swampish (late eutrophic), gar and bowfin populations also rise.

Features of lakes from different trophic classes help dictate fish behavior. To be clear, no one 100% understands fish behavior -- if they did, fishing would be no fun, and a whole gaggle of very smart fish biologists and ecologists would be out of jobs. That being said, there are some general trends: Example: Because mesotrophic lakes stratify in the summer, creating a more favorable top/shallow layer (warmed by the sun => algae => photosynthesis => oxygen) and less favorable bottom/deeper layer (cooler => algae die => decomposition => less oxygen), fish must move shallower in the summer, producing some good fishing there Example: Because of low algal growth and little sediment, oligotrophic lakes have deep cold water with greater oxygen content (with cold water holding more dissolved oxygen than warm water); therefore species tend to sit in deeper water, requiring anglers to more regularly employ deep water techniques

Even if you’re already a great lake angler, appreciating lake trophic classes can make you a more thoughtful sportsman/woman, outdoorsman/woman or conservationist. It might seem almost silly or pointless to think about lakes aging like humans do, but it’s ultimately helpful. The reality is that both natural and human factors can affect a lake’s trophic class, and the human impact in particular cannot be overstated. For example, agricultural run-off, residential fertilizers, excessive trash, sewage, dust and rain-borne urban particles can all increase sediment and algal biomass, driving an otherwise oligotrophic lake into a eutrophic or hypereutrophic state. Among other things, this means that: As anglers, we should appreciate every opportunity to get out on different lakes. As they age, the features and characteristics of lakes will change, and there are no guarantees that conditions can be replicated in the future. Thinking about trophic classes (beyond the boring biology) is a great reminder to cherish every day out on your favorite water! Without thoughtful conservation, the lakes we fish now may not be there (or may be very different) for our children. Not all change is bad, but as we support other efforts to preserve waters for future generations (e.g., catch-and-release, avoidance of overfishing), we should at least give thought to how our personal actions (litter, dumping) and industry will change the water we’ve come to know and love. 

[houseofliao]

On the way in, big brown trout always seem to have another run or two in them, don't they? There are few things quite like feeling and respecting the power on the other side of the line. Thinking back with gratitude on my day on a remote stream (patiently) tangling with this beaut. #fishon

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"For any fisherman there's always a new place, a new horizon." 

Definitely a great blessing and truth for me, honing my technique and hooking into this 3.5 lb chunk while exploring a new place with new friends. Appreciate both the guys and the fish "coming out to play", as well as the gorgeous weather; those of us who've fished long enough know to never take any of those elements -- good company, weather or bite -- for granted!

[houseofliao]

What Do Snakeheads Eat?

(Image credit: Brian Gratewicke, Wikipedia, CC BY 2.0, link here)

Series Intro: As part of my foray into multi-species angling, I was recently introduced to the idea of snakehead fishing by a couple stand up local guys. Having earned my early stripes hunting for trout on the fly, I hadn’t ever really given the snakehead -- and the debate it invariably stirs up about invasive species -- much thought or consideration. However, faced suddenly with the opportunity to add it to my list of species caught, I quickly resolved to learn as much as I could about it. 

The first and most enduring lesson is clear: snakeheads are fascinating, if not partially misunderstood, fish. The remainder I’ve tried to chronicle here in this series of articles, with a simple and straightforward goal: to ‘pay forward’ the graciousness other anglers have shown me and share some knowledge that might help others.

In these posts, the usual caveats apply: I firmly believe that an ounce of evidence is worth more than a thousand pounds of opinion, a sentiment that is probably truer for fishing than most other activities (we’ve all heard a few tall tales from fellow anglers, amirite?). For sure, experience is critical and there’s much to be learned from experiential wisdom. But another vital task of any good angler is to continually integrate his/her experience with general knowledge and data. That ethos -- a data driven approach to improvement -- is the one from which I write. 

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Personally, the most important question when it came to Northern Snakehead (Channa argus) was also the most obvious: what does it eat? After all, knowledge about its diet not only increases the short-term likelihood of hooking up; it also improves the long-term chances of understanding how snakeheads might interact over time with native species in different bodies of water. 

Enter a study done several years ago [1] in which researchers et up to compare the snakehead diet to that of other native species. Using boat electrofishing, they sampled 5 species -- Snakehead, Largemouth Bass, Yellow Perch, American Eel and Longnose Gar -- in the lower Potomac River catchment area. Gut contents were evaluated systematically for evidence of different fish, crayfish, insects, frogs, turtles and mice. Here’s what they found:

Snakeheads eat other fish

They eat a lot of fish (97% by frequency, 99.5% by weight)

The most frequently consumed fish was the banded killifish, while the fish that made up most of the snakehead diet by weight was the bluegill

Non-fish (e.g., crayfish, insects, etc) made up a measly 1.1% of the snakehead diet by weight

(Image credit: Terrapin83, Wikipedia, CC BY 2.5; link here)

(Image credit: Ltshears - Own work, CC BY-SA 3.0; link here)

Snakehead and Largemouth Bass diets overlap

As measured by a metric called Schoener’s index (the computational details of which are beyond the scope of this post), there was a biologically significant dietary overlap between snakeheads and largemouth bass

(Image credit: Jonathunder - Own work, CC BY-SA 3.0, link here)

However, compared to snakeheads, local predator species (bass, perch, eel) consumed invertebrates far more frequently (up to 10-20X more); they were estimated to be 60X more important to the bass (in terms of % by weight) 

Small snakeheads eat small fish, large snakeheads eat larger fish

Here, the data affirms common sense: based on an approach called indicator species analysis (the specifics of which are again beyond the scope of this post), small snakeheads preferred banded killifish, while large snakeheads preferred yellow perch. 

Beyond the usual caveats related to research results, it’s important to remember the potential differences in local snakehead populations. Genetic testing suggests that snakeheads in the Potomac are likely unrelated to those found in other regional waters (e.g., Crofton, MD, Shrewsbury, MA, Philadelphia, PA) [2] and subsequent work has shown at least several distinct genetic snakehead groups [3]. Therefore, while potentially suggestive, the results from the Potomac River sampling may not directly apply to other snakehead populations.

References:

1. Saylor RK, Lapointe NWR, Angermeier PL. Diet of non-native northern snakehead (Channa argus) compared to three co-occurring predators in the lower Potomac River, USA. Ecology of Freshwater Fish. 2012; 21:443-452. 2. Potomac snakeheads not related to others. The Baltimore Sun. Accessed on April 21, 2016. Available at: http://www.baltimoresun.com/news/maryland/bal-md.snakeheads27apr27-story.html. 3. Wegleitner BJ, Tucker A, Chadderton WL, Mahon AR. Identifying the genetic structure of introduced populations of northern snakehead (Channa argus) in Eastern USA. Aquatic Invasions. 2016;11.

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Do Red Hooks Catch More Fish?

I ran into a few (predominantly crappie and bass) anglers on the water a few weeks ago who used exclusively red hooks. “A well-known secret to catch more fish,” they said, surprised that I’d never heard it before. When I explained that I was new to bass angling, they elaborated that red hooks -- by reminding fish of blood and wounded forage -- induced more frequent and aggressive strikes than black or silver hooks. 

I did a little digging, and it turns out that for some time now (possibly dating back to the 1980s and 1990s), there has been a surge in production and interest in red tackle. The wounded forage argument, along with another theory called “gill flash” (the idea that the gills of feeding fish become engorged with blood, and trigger other fish into a feeding frenzy), seems to have given rise to entire series/lines of tackle. 

More recently, however, the pendulum seems to have swung back the other way, with some anglers pushing back against the idea that red hooks help at all. A popular counterargument -- among amateur and professional anglers alike -- seems to be that “red is the first color to disappear underwater”, logic that tries to dispel the red hook myth even as it gives life to the argument made by some marketers that red line (because the color disappears) is best for hooking up with fish. 

The fundamental disconnect of all of this notwithstanding -- red line disappears and increases hook-up ratios, but red hooks stand out and increase hookup ratios? -- which side is right? Do red hooks catch more fish? 

I am of the persuasion that an ounce of evidence is worth more than a thousand points of opinion, particularly when there’s hype and information sources (e.g., tackle companies and reps) that are subject to strong incentives, so here are some facts based in science:

First, the ability to see colors underwater depends on fish (and their eye lenses). Light bends (refracts) when moving between two mediums, such as from air to water. Fish have extremely round, bowed out (convex) lenses in their eyes, which allows them to focus light in ways that we can’t as humans (as an interesting fact, this is why convex camera lenses that bend images are called “fisheye lenses” in photography). 

Because there is some variation in anatomy among fish species, this suggests that color vision differs based on which type of fish is being discussed.

Second, the ability to see colors underwater depends on how water absorbs light with increasing water depth. Water absorbs light, and with increasing depth, the amount of light absorbed increases (leaving less light overall). However, light of different wavelengths is absorbed differentially, with light of longer wavelength absorbed more quickly than that of shorter wavelength. From the graphic below, you will notice that within the visible spectrum of light, red has the longest wavelength, and purple the shortest. In other words, red is absorbed ‘first’ and blue/purple is absorbed ‘last’ as water depth increases. One important note here is that ‘absorbed’ does not equal ‘disappear’; instead, assuming there is some degree of light at a given water depth, objects with colors that have been absorbed will appear dark/black. 

This suggests that given a fixed water depth, red/orange colors are absorbed more fully than blue/purple colors.

Third, the ability to see colors underwater depends on the chemical properties of the body of water. Beyond the general properties of water mentioned above, light absorption also has to do with the presence and composition of water solutes (e.g., salts, sediment, chemicals). In fact, some work suggests that the order of how colors are absorbed in water can depend on turbidity (how clear the water is), and that when water is turbid, red can actually be absorbed after blue. 

(image credit: UW Sea Grant Institute; link here)

This suggests that water conditions -- e.g., stained from a recent storm, streams with stone vs mud bottoms -- affect how color is perceived by fishes.

What this science tells us about whether red hooks catch more fish:

1. In shallow, clean water, red is visible and so if whatever theories an angler believes about ‘gill flash’ or ‘bleeding bait’/wounded forage ever hold true, they would under these conditions. Conversely, the idea that red line is better because “red disappears first” is unlikely to be true in these situations. 

2. In contrast, ‘gill flash’ or wounded bait theories are probably moot in deeper water beyond the point where red is absorbed; beyond that point, lures will appear dark/black, which may or may not help an angler catch fish, depending on the other non-color properties of the lure (e.g., opacity, profile, silhouette, etc). Unfortunately, this also means that red line is again unlikely to be helpful because even with the red color absorbed, the silhouette of an opaquely colored line is more likely to spook fish (think: monofilament vs fluorocarbon comparison) than help catch them, at least compared to other fishing line of the same pound test

Ultimately, do red hooks catch more fish? Again, this depends on a number of fish-, water- and condition-specific factors, and probably some that we don’t yet fully understand. But overall, the answer is “it depends”. Nonetheless, the following is an evidence-based approach to bass and similar fish:

-in shallow, clear water, the use of red hooks or lures could confer an advantage based on “gill flash” or “bleeding bait” theories -in deeper water beyond 20-25 feet (assuming minimal turbidity), any potential advantages of these theories likely wanes

-the rationale behind red fishing line seems unhelpful in all conceivable situations (highly visible and unnatural in shallow,  clear water; non-red but still dark and potentially silhouetted in deeper water, assuming anglers fish that deep in the first place)