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Keepemwet Fishing, Fisheries Research

KWF_ScienceDirect.jpg

At Keepemwet Fishing we believe that communication and knowledge sharing between the fisheries science and recreational angling communities is a two way street.   For example, anglers can learn more about fisheries science, and scientist can learn about the issues that are important to anglers and this can help inform their research.  We need this type of dialogue and interaction to make sure that catch-and-release is effective.   Scientists communicate and share their work and ideas through the publication of peer-reviewed articles in scientific journals, and so, here is our first contribution on Keepemwet Fishing to science literature.

"There is a growing body of catch-and-release (C&R) science showing that adjusting the way fish are caught, handled, and released can reduce impacts on individuals and populations. However, a major caveat is that C&R will be a more effective conservation tool if best practice guidelines stemming from the science are understood, embraced, and adopted by recreational anglers. In recognition of this, Keepemwet Fishing (KWF) has emerged as a nonpartisan movement to provide simple, clear, and accurate C&R guidelines that transcend species and subcultures within the recreational angling community". Full report here.

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Fish reflex tests - a valuable tool for anglers

by Dr. Jake Brownscombe, PhD
Research Associate, Carleton University
Keepemwet Science Ambassador

“Have a seat, Jake” the doctor said as she pulled out a small rubber mallet and proceeded to thump me on the knee with it. My leg kicked outward involuntarily. “Your nervous system is in good condition” she assured me.

If you grew up on this planet, you know the doctor was checking my knee-jerk reflex. Perhaps lesser known, the speed and intensity of this reaction can indicate internal nerve damage or the presence of disease. It’s a simple external test that indicates what is going on inside of the human body.

Fish have reflexes too. And they can tell us a lot about their internal condition, such as their level of stress, ability swim or to perceive predators. This is particularly useful for anglers because fish cannot tell us how they are feeling. If you ask a fish “If I let you go, can you swim well enough to survive?” its response will be inconclusive. Trust me, I’ve tried… more times than I’d care to admit.

The idea behind catch-and-release fishing is that the fish will survive, grow bigger to be caught again, and continue to contribute to the population. Yet, we know this isn’t always the case. Fish sometimes suffer mortality after release due to stress or injuries associated with angling (but the odds of this can be minimized substantially by using best practices - see this paper for an overview). Whether or not a fish survives depends on its condition, which can be hard to assess as an angler without any fancy medical or veterinary tools.

That is, until recent research developed a set of reflex tests that can be applied to fish, by anglers, to assess their condition. These are the four most effective reflex tests, how to do them, and what they tell you:

 

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1. Escape response

How to do it:  With the fish in the water in a net or livewell (scientific holding pen shown here), approach the fish from behind and grab at its tail. Observe if the fish attempts to escape.

What it means: If a fish doesn’t try to swim away it fails this test, has at least some level of impairment and could be at risk of mortality - other tests will provide further insights.

 

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2. Righting response

How to do it: Flip the fish upside down (belly up) in the water and let go. Observe if the fish rights itself within 5 seconds.

What it means:  If a fish cannot right itself within five seconds it fails this test, and is in poor condition and at risk for mortality.

Pro tip: Count the amount of time until the fish rights itself and note whether it struggled to do so. If a fish rights itself quickly and with ease, it is in good condition to swim away immediately.

3. Regular ventilation

How to do it: Holding the fish in the water, observe for regular, consistent ventilation (opening and closing) of the operculum (gill plates).

What it means: If a fish isn’t ventilating at regular intervals, it fails this test, and is highly impaired and at high risk for mortality.

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4. Eye tracking

How to do it: Holding the fish in water, roll the fish side-to-side, observing whether its eye(s) remain level (passes test), or roll with the body (fails test).

What it means: If a fish fails this test, it is highly impaired and at very high risk of mortality

Concept diagram Reflexes.jpg

While these aren’t true reflexes by strict definition, they are responses that are always present in fish unless impaired due to stress. The above tests are presented in order of operation, starting with escape response. If a fish fails this test, proceed with the righting response test, and so on. If a fish has no reflex impairment, the best course of action is to release the fish immediately to reduce handling time. However, if there is reflex impairment, particularly loss of righting response, anglers can hold fish in a net or livewell until its condition improves. Further, on any given fishing day, if captured fish are repeatedly in poor condition, anglers can consider altering their fishing practices (e.g., use different lures or fish in different locations) to minimize their impact on fish.


The Science:

The concept of using reflex tests as an indicator of fish condition was first developed and applied in the context of commercial and aboriginal seine net fisheries for Pacific salmon (see these two articles for reference) 1, 2. Based on the success of multiple studies in predicting salmon survival using reflex tests, scientists began apply these tests to recreational fisheries. This study found bonefish with impaired righting response are six times more likely to suffer predation post release (see Finsights #5). Another study later showed that reflex impairment indicates that bonefish have reduced swimming and decision-making capabilities post release, which is why they are more vulnerable to predators. Reflex tests are now used widely as measures of fish condition for diverse species such as sharks, great barracuda, largemouth bass, and fat snook. As science continues to develop the relationship between reflex tests, fish condition, and survival, these tools will become increasingly useful for anglers to assess the condition of their fish and make informed decisions about how to treat the fish prior to release.

 

 

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FINSIGHTS- TRANSLATING THE SCIENCE OF FISHERIES REPORTS #9

Finsights #9– How do you handle fish? Paul Moinester/Keepemwet Fishing photo.

Finsights #9– How do you handle fish? Paul Moinester/Keepemwet Fishing photo.

You’ve hooked up on a fish.  You fight it, reel it in, and get ready to land it.  Do you reach for a net? A lip gripping device? Or just stick your hands in the water?  And what do you do once you have ahold of the fish?  Does it stay in the water? Does it go in a boat or a livewell?  

How we choose to handle the fish we catch and release can have a huge impact on the health of those fish.  Some of the negative effects of handling on fish we can actually see (such as the loss of scales or equilibrium) but many we cannot, either because they are invisible to the naked eye, are internal, or occur after we release the fish.  

This study uses a clever way to examine some of the invisible injuries to fish and how different handling techniques impact the skin of fish. All fish are covered with an epithelial layer, which is on top of the scales and provides a barrier to pathogens, UV light, and desiccation (drying out). There is also mucus on fish, but the amount varies among species. Unlike with humans, the outer layer of cells on fish are living and a disruption to the epithelial layer creates a susceptibility to infection.

Fluorescein is a non-toxic dye that can be used to examine epithelial damage on fish (it is some of the same stuff used by detectives to look for blood at crime scenes). After being dipped in a solution containing fluorescein, areas on a fish with damaged epithelium with glow green under a UV light.   

What did they do?
    •    Used fluorescein dye to examine how different handling methods damage the epithelial layer on largemouth bass and northern pike.
    •    Handling techniques included different types of nets, a lip gripping device, and placing a fish on a variety of boat surfaces.
    •    Largemouth bass from a semi-professional live-release tournament were also measured for epithelial damage.
    •    After being subjected to the fluorescein dye, fish were photographed under a UV light and damaged area (seen as green on the photos) was measured using computer software.

A northern pike photographed under UV light after being exposed to fluorescein dye.  The green areas indicated epithelial damage from handling. Image from  linked  report.

A northern pike photographed under UV light after being exposed to fluorescein dye.  The green areas indicated epithelial damage from handling. Image from linked report.

What did they find?
    •    Northern pike had more epithelial damage than largemouth bass across all handling methods
    •    Largemouth bass from the tournament had the most epithelial damage. This isn’t surprising as they were often subjected to multiple handling methods, where the experimental fish were only subjected to one handling method.  
    •    Rubber, non-knotted landing nets caused less damage than nylon, knotted nets for pike. For bass, there wasn’t a difference between net types.  
    •    All fish placed on a boat surface had epithelial damage and those placed on indoor/outdoor carpet had more damage than those placed on a bare metal surface.

Why is this study important to anglers?
This study shows that different species can have different reactions to the same type of handling. This is one of the reasons the science of catch-and-release is so interesting and can be confusing, and why ‘one size fits all’ rules may not apply. Nevertheless, here are two generalities that we can uphold because they are supported by this study (and others) and follow the precautionary principle – the idea behind “better safe than sorry”.  

    •    This study confirms what many anglers have thought for a long time; that softer, rubber, non-knotted nets are better for fish.  
    •    Likewise, contact with boat surfaces (carpet or smooth metal) causes damage to fish and rough surfaces cause the most damage. I would argue that placing fish on any hard surface (rocks, logs, boats) either wet or dry has the potential to cause epithelial and internal damage to fish. Whenever possible, fish should be held over water deep enough for them to swim in. But remember, we also need to #KeepEmWet.

See the complete study here.

Happy Fishing!
Sascha Clark Danylchuk

 

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FINSIGHTS- TRANSLATING THE SCIENCE OF FISHERIES REPORTS #7

Finsights #7 – “I saw the fish swim away so it must be fine” - Part 3

Finsights #7  Robert Lennox Photo

Finsights #7 Robert Lennox Photo

My last two posts have been about the range of possible lethal and sublethal impacts of catch and release angling on fish, and I want to round out the discussion with one last post. When it comes to sublethal effects, it’s fairly easy to comprehend the direct consequences of angling on an individual fish. What can be more difficult to understand and discern scientifically is how angling could impact an entire population of fish.

One way to get at population level effects is to examine how angling impacts the fitness of fish. Keepemwet Science Ambassador John McMillan recently provided a nice explanation of what fitness means for fish - the ability of an individual to contribute viable offspring to the next generation.  So, a decrease in fitness would be a decrease in the number or the quality of offspring from a given fish.

Anglers landing an Atlantic salmon. Robert Lennox photo.

Anglers landing an Atlantic salmon. Robert Lennox photo.

A scientist releasing a studied fish. Robert Lennox photo.

A scientist releasing a studied fish. Robert Lennox photo.

The research paper for this blog post specifically looked at whether catch and release angling impairs fitness. The scientists were able to take advantage of the unique geography of a small river in Quebec, Canada that also contained a fish ladder, which allowed for a complete inventory of Atlantic salmon that entered the river to spawn. Every fish that entered the river was sampled for their genetic makeup. Genetic samples of fish are most frequently obtained by cutting off or punching out a very small piece of fin (it doesn’t bleed and quickly grows back).  

Atlantic salmon in the river. Robert Lennox photo.

Atlantic salmon in the river. Robert Lennox photo.

What did they do?
    •    All salmon entering the river at a fish ladder were genetically sampled and their length measured.
    •    All anglers on the river were asked to fill out a questionnaire and take a genetic sample of each fish they caught and released.
    •    The following year, fry (baby salmon) were sampled in the river to determine parentage.

What did they find?
    •    20% of the salmon in the river were angled and were the parents of 22% of the offspring. This means that the fish that were caught and released were able to spawn.
    •    Larger angled salmon produced significantly fewer offspring than non-angled salmon, however, there was no difference in number of offspring (in angled vs. non-angled fish) for smaller salmon.
    •    Air exposure decreased the fitness of salmon.  Depending on water temperature, the reproductive success was 2 to 3 times lower for angled salmon that were air exposed versus those that were not.  

Why is this study important to anglers?
    •    Once again, we see that air exposure is bad for fish. In this case, it’s bad for the next generation of fish.  
    •    All fish are not equal – larger fish can be more susceptible to the sublethal effects of angling. This is true when it comes to fitness, as well as when it comes to stress (link to Finsights #4). As anglers, we need to treat the larger fish that we pursue with the utmost care and respect.  Angling can impact large fish in more ways than it does smaller fish and therefore we have an extra duty to Keepemwet.

Link to full research paper.

Happy Fishing!
Sascha Clark Danylchuk

 

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Finsights- translating the science of fisheries reports #5

Finsights #5 – “I saw the fish swim away so it must be fine” - Part 1

The "grey ghost" Alex Filous photo.

The "grey ghost" Alex Filous photo.

I can’t tell you how many times I’ve heard an angler say, “I saw the fish swim away so it must be fine.”  And I’ve certainly hoped for the same on countless occasions; that when I release a fish that’s vigorous and darts out of my hands it will be fine.  The scientist in me, however, knows that this statement can be false for a number of reasons.  

Sometimes the fish we catch and release get injured or die.  There is no getting around that fact and there is only so much that is in an angler’s control.  However, by better understanding the processes that can lead to negative outcomes for fish, we anglers can adjust what is in our control to ensure that more fish live to be caught another day.  

This post is the beginning of a series addressing what can happen once we release a fish.  This particular post addresses post-release predation, and (in full disclosure) a paper authored by me.  Despite the fact that using this paper makes the introvert in me want to hide under the bed, I chose it because it is a fairly straightforward study with results that have a clear application to the catch and release best practices for bonefish.  

What did we do?
    •    Bonefish were caught using fly fishing.
    •    Measured angling time (hooking to landing), handling time (landing to release), air exposure time (cumulative), the presence/absence of blood from hooking, and total length of the fish.
    •    Also noted whether or not the bonefish was able to maintain equilibrium at the time of release.  Having equilibrium = fish that swim away. Lost equilibrium = fish that rolled over or nose-dived and couldn’t readily swim away.
    •    Before release, we attached a small float to the bonefish so that we could follow it (this tracking method was previously tested on bonefish and there was no impact of the float on fish movement and predation)

Post-release predation on bonefish by a shark,  Robert Lennox photo.

Post-release predation on bonefish by a shark,  Robert Lennox photo.

What did we find?
    •    Bonefish that lost equilibrium were over 6 times more likely to suffer predation, either by sharks or barracuda
    •    Longer air exposure and handling times were the biggest contributors to loss of equilibrium
    •    Predators killed most of the bonefish within 20 minutes of release, but not necessarily close to or within easy viewing of the release location.

Why is this study important to anglers?
    •    Air exposure isn’t good for bonefish
    •    Lots of handling isn’t good for bonefish
    •    Catch and release angling in locations with predators (even if you don’t see the predators) can greatly decrease the chance of survival for fish.

Read the full original report here.


Happy Fishing!
Sascha Clark Danylchuk

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FINSIGHTS- TRANSLATING THE SCIENCE OF FISHERIES REPORTS #4

Finsights #4 – Fish can get stressed too

By Sascha Clark Danylchuk

Rainbow trout darts back into it's Alaskan stream after release. Bryan Huskey photo via Bristol Bay Lodge.

Rainbow trout darts back into it's Alaskan stream after release. Bryan Huskey photo via Bristol Bay Lodge.

Before we dive into the study (Meka & McCormick 2005), I wanted to start with a brief discussion of stress in fish.  Scientists measure stress in fish to determine how our interactions with fish (e.g. angling) affects their health and welfare. Just like in humans, too much stress in fish can lead to decreased performance, poor health, and even an increase in the likelihood of death.  There are a variety of indicators that can be used to quantify stress, each with advantages and disadvantages. Two of the more common indicators are cortisol and lactate.

Cortisol: a hormone found in all vertebrates and often called “the stress hormone”.  You could think of cortisol as a messenger, and an increase in cortisol can trigger a response in numerous parts of the body.  When scientists measure cortisol level in blood, we assume that a higher level of cortisol is indicative of a higher level of stress.  

Lactate: a byproduct of extreme muscle activity.  For the athletes out there, it’s related to lactic acid buildup in muscles due to anaerobic activity.  In the context of angling, higher levels of blood lactate indicate that a fish has been exercising more in response to being on the fishing line, and is more stressed.  

So, back to the study, this one examines the stress caused by angling for wild rainbow trout in Alaska.  

What did they do?
    •    Used real angling techniques (spin and fly fishing)
    •    Compared rapid capture fish (less than 2 minutes from hooking to hook removal) to extended capture fish (over 2 minutes from hooking to hook removal)
    •    Took blood samples after the hook was removed to measure cortisol and lactate (and a couple of other parameters, which I’m going to ignore for now)
    •    No air exposure to any fish

What did they find?
    •    Extended capture fish had higher levels of cortisol and lactate
    •    Larger fish took longer to land
    •    All else being equal, higher water temperatures can (but don’t always) correspond with higher levels of lactate and cortisol

Fly fishing the Alaskan backcountry. Bryan Huskey photo via Bristol Bay Lodge.

Fly fishing the Alaskan backcountry. Bryan Huskey photo via Bristol Bay Lodge.

Why is this study important to anglers?
    •    Choosing tackle that reduces the amount of time a fish is on the line and the time it takes to handle the fish and remove the hook is important to reducing stress.  
    •    Bigger fish that fight longer are likely more stressed

See the full report: Physiological response of wild rainbow trout to angling: impact of
angling duration, fish size, body condition, and temperature
Julie M. Mekaa,∗, Stephen D. McCormickb

Happy Fishing!
Sascha Clark Danylchuk

 

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FINSIGHTS- TRANSLATING THE SCIENCE OF FISHERIES REPORTS #2

FINSIGHTS- TRANSLATING SCIENCE OF FISHERIES SCIENCE #2

by Sascha Clark Danylchuk

Taking a non-lethal blood sample from a bluefin trevally in French Polynesia. Photo provided by author.

Taking a non-lethal blood sample from a bluefin trevally in French Polynesia. Photo provided by author.

Read post #1 Introduction to Finsights here.

The writing style of scientific manuscripts makes many people cringe. The use of the passive voice (scientists rarely use “I” or “we”) and the density of the writing can make scientific papers difficult to follow. Similarly, discerning the important aspect of the study can be tricky because scientists go to extremes to avoid adjectives and subjectivity and almost everything written is given equal credence. I’ve put together a brief description of the major parts of a scientific manuscript and what to look for in each section for improved comprehension.

Abstract: brief summary of the study and its findings. This is the place to start to see if a paper might be relevant and interesting.

Introduction: background of pertinent previous studies, and goals and hypothesis for the present study. From the introduction you should understand the motivation for the study.  It’s also a great place to find references to other studies that might be of interest.

Methods: a description of the study process, with enough detail so that another person or research team could replicate it. This can be very dry, and it’s supposed to be that way.  

Results: a description of the findings and the results of statistical analyses. This can be confusing unless you have a good grasp of statistics. Look for terms like “statistically significant” to recognize what is important. The figures and tables (graphs, maps, and diagrams) will also highlight notable trends and findings, however there is a definite skill to figuring out what is scientifically meaningful.

Discussion: an objective interpretation of the results and statistics, and how the findings add to our understanding of the subject matter. A good discussion should key in on the results that are the most meaningful. The discussion also often covers the limitations of the study, which are important for understanding how broadly the findings can be applied (e.g. does this apply to all trout, only brook trout, or only brook trout in New York?).

Keepemwet Fishing Science Advisor Andy Danylchuk and field assistant Kim Ovitz doing work on Golden Dorado in Northern Argentina.  Tyler Gagne photo.

Keepemwet Fishing Science Advisor Andy Danylchuk and field assistant Kim Ovitz doing work on Golden Dorado in Northern Argentina.  Tyler Gagne photo.

When I read a manuscript, I usually spend most of my time on the abstract, introduction and discussion.  It’s these sections that get to the core of the subject matter and provide most of the type of information that an angler would find interesting.  

Lastly, it’s important to remember that each study and corresponding manuscript is an incremental step in addressing a large subject matter. Rarely can any one study tackle all questions, but put together, over time, scientists strive to find complete answers to complex problems.

Happy fishing!
Sascha Clark Danylchuk

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Finsights- Translating the Science of Fisheries Reports

Introduction to Finsights- Sasha Clark Danlychuk

I have been seeking water for as long as I can remember. As a child, it was the beach or a mountain stream in which to play. Eventually, I began to search for the creatures living in the water and it was no great surprise that this led me to become a fisheries scientist. I still love to play in the water, and more often than not, that involves fly fishing.

The author Sascha Clark Danylchuk cradling perfection in the form of a bonefish.

The author Sascha Clark Danylchuk cradling perfection in the form of a bonefish.

More and more, however, I find the intersection between my work as a fisheries scientist and my passion as a recreational angler to be messy and convoluted. I admire that innate conservation ethic exhibited by many anglers, but find the lack of scientific backing to their practices frustrating. Likewise, I appreciate my colleagues’ quests to solve issues and find sustainable solutions, but I am aggravated that their ideas rarely make it past esoteric scientific publications.

In my quest to clarify fisheries science to recreational anglers, and to encourage scientists to make their work accessible to a wider audience I have teamed up with Keepemwet Fishing for a blog series I am calling Finsights in which I will “translate” some of the most important scientific studies on recreational angling so that they can be understood by more people.

But, let’s begin with the scientific publications process and why scientists write in such a complex, dense, and let’s face it, dull style. Scientific publications were developed as a means for scientists to make their work known and judged objectively. The process of publication requires a scientist (or, more often than not, the group of scientists) involved in a study to write a manuscript, which follows a very specific format, and to submit the manuscript to a journal of their choosing. There are hundreds of journals, and they vary in subject matter as well as quality. Once a manuscript is submitted it is read by an editor or associate editor who then must find 2-3 anonymous peers to also review the manuscript and decide if it is worthy of publication. Publications are reviewed based on the quality and merit of the study as well as quality of writing. If the manuscript is accepted (usually after some revisions are made) it is published. If it is rejected, the authors can submit it to another journal and try again. Throughout this entire writing process the goal is precision; the writing has to be absolutely accurate and the wording extremely precise, making the journal articles both dense and generally dull (no flowery adjectives or subjectivity allowed!).  There is also a limit to how much the authors can extrapolate their results.

Almost too scenic to fish. Sascha stream side in Patagonia.

Almost too scenic to fish. Sascha stream side in Patagonia.

The advantages of this process is that there is an ongoing body of literature which has been judged as sound and provides the basis of further study for any given scientific subject. The number and quality of peer-reviewed publications has also become the standard by which scientists are evaluated.

The disadvantages are that the whole process (from submission to publication) can take months to years, meaning that by the time one study is published the scientist is often working on the next study. Also, you cannot publish a study in more than one journal, and authors of manuscripts are not paid for their publications, if anything they pay the journal to publish their work.

The realities of the peer-review process can also hinder publication. Not only is it often difficult for editors to find reviewers for a manuscript (reviewers volunteer their time and it can take many hours to properly review a single manuscript), but I have also heard many stories of manuscripts that were rejected because an editor failed to find a peer-reviewer who was a true peer and adequately understood the subject matter of the manuscript.  The manuscript can also be rejected based on the challenge to adequately communicate the science, or that the science simply wasn’t ‘up to snuff’.

Submerged brown trout. Bryan Huskey photo.

Submerged brown trout. Bryan Huskey photo.

Next time I’ll go through the major sections of a scientific paper and provide some hints for discerning the important bits and finding the ‘highlights’ that are important to anglers interested learning more about the fish they are after.

Happy fishing!
Sascha Clark Danylchuk

 

 

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Involving recreational fisheries stakeholders in development ofresearch and conservation priorities for mahseer (Tor spp.) of Indiathrough collaborative workshops

The mahseer (Tor spp.) of India are a group of potamodromous cyprinids currently facing numerous challenges in their native ranges including overfishing, pollution, and hydropower development. As a result of such challenges, four of the seven Indian species of Tor have been listed as ‘Endangered’ on the IUCN Red List, including two of the most popular recreationally fished species, Tor khudree and Tor putitora.Stakeholders in the mahseer recreational fishery may serve as an ally for this group of iconic fishes, fostering aquatic stewardship and providing livelihood alternatives for poachers. Yet, information regardings pecies-specific responses to recreational fishing practices is lacking and a 2009 decree equating fishing with hunting in the Indian Wildlife Protection Act (1972) has since 2011 effectively banned angling within protected areas and rendered the future of mahseer recreational fisheries elsewhere uncertain. Read More.

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Best practices for catch-and-release recreational fisheries – anglingtools and tactics

Catch-and-release angling is an increasingly popular conservation strategy employed by anglers voluntarily or to comply with management regulations, but associated injuries, stress and behavioural impairment can cause post-release mortality or fitness impairments. Because the fate of released fish is primarily determined by angler behaviour, employing ‘best angling practices’ is critical for sustain-able recreational fisheries. While basic tenants of best practices are well established, anglers employ adiversity of tactics for a range of fish species, thus it is important to balance science-based best practices with the realities of dynamic angler behaviour. Here we describe how certain tools and tactics can be integrated into recreational fishing practices to marry best angling practices with the realities of angling. While the effects of angling practices vary considerably across contexts and conditions, we also outline available methods for assessing fish condition by examining physical injuries and reflexes, which enable recreational anglers to make educated real-time decisions related to angling practices, as well as when, where, and whether to release captured fish based on their probability of survival. In cases where fish are in poor condition, there are recovery tactics available that can improve survival, although this is among the most understudied aspects of angling practices. Read More.

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Influence of hook type and live bait on the hooking performance of inline spinners in the context of catch-and-release brook trout Salvelinus fontinalis fishing in lakes

The objective of catch-and-release angling is for the fish to survive with minimal fitness consequences. However, fish survival can be compromised by a number of factors, especially anatomical hooking location. To evaluate whether hook type or bait influence hooking outcomes, we tested different combinations of hook (treble or single siwash hooks) and bait (hook tipped with worm or no worm) while angling for brook trout (Salvelinus fontinalis) with inline spinner-style fishing lures. Read More.

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Characterizing information on best practice guidelines for catch-and-release in websites of angling-based non-government organizations in the United States

Recreational catch-and-release angling is an important tool for managing fish stocks. As recreational fishing is often a culturally or community-based activity, many anglers look to local grassroots and other non-government organizations (NGOs) as a source of information regarding their angling practices. Read More.

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Best practices for catch-and-release recreational fisheries – angling tools and tactics

Just released study involving Keepemwet Fishing Science Advisor Dr. Andy Danylchuk.

"Catch-and-release angling is an increasingly popular conservation strategy employed by anglers vol-untarily or to comply with management regulations, but associated injuries, stress and behaviouralimpairment can cause post-release mortality or fitness impairments. Because the fate of released fishis primarily determined by angler behaviour, employing ‘best angling practices’ is critical for sustain-able recreational fisheries." Read more.

 

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