Monday, March 18, 2019

Piscivores in the Crosshairs: The Tenuous Relationship Between Fish Eating Fauna and Anglers

Anglers and animals that eat fish have long had a complicated relationship, and for obvious reasons. We often have a tendency to perceive fisheries as "ours", and when animals come along that want to eat fish, we say "they've come to eat our fish". I've felt this way in the past, and it wasn't until fairly recently that I've shaken the last bits of these perceptions and have come to accept the importance of piscivorous birds and mammals in our ecosystems. I propose that in nearly all cases the long-lasting decimation of fisheries can rarely be traced to a non-human animal. We are the root of all fisheries problems, and culling another species is rarely the answer. This is a controversial stance, but I am only becoming more firmly balanced here the more I learn. It's going to be a lot harder to budge me from it than it was to get this cormorant to leave his log. 


A big part of my motivation to write this was a Facebook post I saw months ago demonizing mink and otters for the "damage" they do to stocked trout. A few people I had thought better of commented in agreement of that post, and it saddened me. I could sympathize a little because I used to think differently. Through personal observation, study, and a lot of thought both critically and philosophically I realized how ignorant I had been.


Mink and otters were here eating brook trout and Atlantic salmon, as well as other species, well before humans were. Piscivorous mammals and birds and fish evolved alongside each other and through the interactions with each other. The fish evolved to avoid predation by these specific species, and over time a balance was maintained in which the predators were able to take what they needed and the fish populations remained stable. Remember, a predatory species that wipes out its key food source goes extinct. Otters, mink, great blue heron, and cormorants are still here precisely because they don't "eat all of our fish".

Enter the European. Withing a few centuries of being on the continent we wiped out so many salmonid fisheries that they were no longer to our satisfaction. We subsequently decided that the best course of action would be to stock rivers and lakes with trout and salmon, which in some cases resulted in self sustaining fisheries, but far more often resulted in a cyclical fishery that needs to be replenished with further stocking because the fish are not adapted to water we are putting them in. To make a long story short, we stole much of the osprey's, fisher's, mink's, otter's, and cormorant's food supply, replaced it with a cheap knock off, and get pissed off when they use it. How selfish is that!?



The hatred of trout eating wildlife isn't limited to hatchery fish though. I've seen blame for declining numbers of brook trout in certain streams thrown at these same species, and I've done the same myself. I challenge you, fellow anglers, to show me one example of a stream in which native fauna alone permanently extirpated native brook trout. That simply isn't how predator species operate.
A mink will occupy a watershed niche as long as easy hunting exists, leaving for the next location when what is left are the fish most adept at avoiding its predation. This predator prey relationship and natural selection actually improves the genetic vigor of fish populations, though it may temporarily make fishing noticeably slower. It is a crucial natural process that we shouldn't try to interrupt.

In the current time in the Northeast perhaps the most clear example of a piscivore in the crosshairs are seals. While most aquatic megafauna are making modest comebacks in the nearshore and inshore waters here, seals and their primary southern range predator, the great white shark, have exploded onto the scene in a far more abrupt and stunning manner. As seal numbers have exploded there are basically too camps calling for their number to be culled: anglers that don't want the seals eating "their" fish, and people that don't like the sharks that the seals attract. Based on what you have read here so far you probably know where I am going. I don't believe either camp has a leg to stand on.


Seals eat an immense tonnage of fish, that is factual. And they are one of an adult striped bass's only three significant predators. They almost certainly eat more than sharks. 

But that's where things break down. The idea that culling seals is good for striped bass fisheries is dangerous when the third and final predator of striped bass is Homo sapiens. Based on every bit of data I have had access to recently, it is human consumption and release mortality for which the bulk of the decline in striped bass can be attributed. The fishing in areas where seal numbers have increased, like Monomoy Island, has gone downhill, but to suggest that because those striped bass aren't there means they aren't anywhere seems ridiculous to me. This is important to note: when we're talking about a migratory species being influenced by a great many factors, different places have their times. Migratory striped bass have been dodging seals for thousands of years. Monomoy had its time, and it may someday have its time again. But I suggest that we should let seals do there thing, let the seal's predators cull them naturally, and cull the human take instead. I have not seen data that indicates that seals are a driving force in population-wide and range-wide shifts for striped bass, and as with brook trout the striped bass have evolved in correlation with non-human predation. I do not see a reason to point the finger at seals for the striper population crash. You can certainly point at seals as the reason for a lack of stripers in certain areas, but we need to get over that. Healthy ecosystems are more important than our recreation, and the only way seal numbers will be culled naturally is by letting their numbers fluctuate normally and attract more and more sharks. Only under circumstances in which seals could be singled out and proven to be pushing striped bass towards a legal listing under the ESA should culling be considered. This has only become my stance as of very recently and I know and respect a lot of people that will disagree. But at this point some really substantial evidence would need to be put in front of me to change my mind.  


Birds and mammals aren't the only animals targeted by frustrated anglers. Oftentimes, other fish are the target. Many anglers value some fish species over most others, and it isn't infrequent that fish like suckers, gar, bowfin, and muskie are singled out for eating the eggs, fry, or adults of fish that are considered more desirable. White suckers and redhorse are left to rot on the banks for eating trout eggs. Bowfin and gar are maimed for eating bass. Muskie are killed for eating bass or walleye. In all of these cases their is little actual evidence with which to justify the actions. I have no problem with killing and using non-native species withing the law and reason, nor the killing with prejudice of invasive species. But I do have a huge problem with the killing, maiming, and wanton waste of native species because they are perceived as a threat to oftentimes non-native, "more desirable" species. As with everything I have discussed so far, this is something I am guilty of doing at one time. I killed fallfish in a brook trout stream because I was ignorant and because I valued brook trout more. That I did such a thing disgusts me. I am deeply, deeply ashamed that I did this. Since coming out of the dark and actually learning the realities of native species and small stream ecology I have been doing all I can to try to right those wrongs. It makes me sick to my stomach to know I had been so destructive and prejudiced towards something I now absolutely adore and would put myself in harm's way to protect. Even though fallfish, gar, white suckers, bowfin, and muskie are in absolutely no danger of extinction at the present, killing them for no reason other than perceived damage to a species you like more is despicable, disgusting, immoral, and beyond reproach. 

Longnose gar, most likely beheaded by an ignorant fisherman. (photo courtesy Tim Aldridge)

(photo courtesy Tim Aldridge)


This brings us to my conclusion: biodiversity is far more important than human recreation. Admit it or not, we are selfish creatures. I am no more immune than anyone. I wish I could go to Monomoy and catch a bunch of big stripers on the flats. I wish every brook trout stream I fished was always consistently loaded with tons of brookies. But more than that I want to live in a bio-diverse world with as little human interference as possible. What the kind of fishery we want isn't always the kind of fishery nature can provide. I recognize that there are circumstances in which human intervention is necessary because we've already messed things up so severely, but I also recognize that the angling community is very heavy handed and shortsighted with its condoning of human intervention. Piscivorous predators are a natural and vital part of every fishery. We need to learn to live with them. I am trying my best to. It is frustrating sometimes, it is difficult too, but if we keep trying make every animal and ecosystem bend to our every whim, we are going to kill this whole thing, ourselves included.

Though that is my conclusion statement I want to end this on a more positive note. A fluffy, adorable positive note. 
In 2017 I came up to see one of my favorite wild brook trout streams in what to me looked like a shambles. Three young common mergansers were diving and hunting for fish, making a huge ruckus. Infuriated to see fish eating birds in "my" stream, I hollered at them. They flew off, and I was left to walk around looking at all the dead fish they had left, mostly suckers and brook trout. I was appalled. I was so angry at those bird for ruining the stream. I talked about it for months. 
Well, those birds didn't ruin the stream. Not even close. If I were to go back today it would be just as good as it was before that incident. I felt bad for how I acted towards those birds and how I talked about them later. So, when I watched a mother merganser abandon her last surviving chick last spring after seeing the rest disappear one by one, I didn't see much of a choice. I was to become that little fuzzy merganserling's interim mama. I dropped everything I had planned for that fishing night and saved that duckling from near certain death by turtle, fish, or hypothermia, and I'm glad I did. I did what I could to take care of it while my mother reached out to some of our old rehabilitation contacts (this was not our first wild animal care experience). One of our friends was eventually able to take the little guy off our hands. Hopefully he has a long, happy life and eats lots of fish. 


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14 comments:

  1. Awesome post RM. I suspect we all travel through ups and downs as you described here. I know I have - both in the water and on land. This is some super info for folks to consider. I think, as with wild predators who may wish harm - and often provide it - to other predators within their range... Humans can default into that same trend of thinking. Further development brings broader ideas and contextual understanding... And suddenly that predator is a fellow inhabitant doing it's thing.

    I catch myself with coyotes and bears still at times: "Dang, they are eating to many fawns!" As you said though, they may eat a bunch for a while, but those does that figure out better hiding areas and the fawns that are better at evasion survive, and become harder for the predators to kill creating a more durable species overall. Net positive.

    The waters get murky when one considers non-native v native fish, their predatory impact and whether they should be allowed to continue, or should some how be eliminated. Musky in Maine for example...

    Increasingly I suspect species evolve and adapt to each other. I know in some cases that may not work, but it seems often enough that the idea of wiping out a newcomer seems almost as dicey as putting the newcomer in the water to start with...

    I'd be curious your thoughts on those things - you have thought deeply about it and researched it!

    Keep well
    Will

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    1. Thanks Will.
      The intentional extirpation of non-native species needs to be viewed on a case by case basis. It's a complex subject that the average person doesn't have much time or patience to delve into properly, which is why there are people believing fallfish are invasive and that bowfin are snakeheads, and that snakeheads are the end of the world as we know it.
      I believe there are species that should be eradicated from all waters they have been introduced to because of the far reaching impacts they have on the ecosystem, like bighead and silver carp.
      I believe there are species that should be removed from certain waters either to prevent the decimation of one or more native species or restore those species, like rainbow trout.
      And I believe there are some species that have enough economic value, too little impact on native species, and are so logistically hard to extirpate anyway that regulating them as a sustainable fishery isn't unreasonable, like black bass and brown trout.
      My rule of thumb is, if you aren't certain something is ecologically and economically beneficial, aren't adept at fish identification, and don't know the law, tread lightly.
      Honestly, there should be some kind of test in order to obtain a fishing license. An awful lot of people know so little about what they see on the water that they regularly unknowingly commit crimes.

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    2. There are a number of separate topics there to explore. On the license issue there a a few different facets. I'll start with Florida. There are so many different species there! If you were to make a meaningful test, it would take 3 years study...
      A friend (from Texas) and I fished Alligator Alley and ended up releasing a fish which, when we got home, we discovered is unlawful to release alive (oscar). We could have been ticketed...
      On the other hand, the fishing rules are written with awareness of the difficulties--certainly seems the case when I read the fishing guides and publications of different states.
      As for knowing scofflaws my god, they are quite numerous. Saturday I went out on all the open sections of my home water and I saw, in my drive through the closed sections, more people fishing illegally than I saw fishing legally--and I spent much more time in the river and walking the legal sections than I did passing through the closed sections in my car. We even watched a warden pull up and ticket a guy. He was 30 yards the wrong side of a bridge.

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    3. I wouldn't suggest a complete and comprehensive test, but if you can't identify an endangered species or understand where and when it is legal to fish... that doesn't sit well with me. Freedom is great until it starts destroying things.
      As best I can tell, and this is with hours of research, there is no law prohibiting the release of exotics like oscars into the same body of water they were caught on FWC books. Killing them is strongly recommended, but it certainly isn't enforced. You'd be hard pressed to find an angler in FL that hasn't released one of the listed "non-native non-game fish". I have. Hell, I did it in front of FWC officers. While talking to them. There are videos and photos of very well known anglers all over the web catching and releasing exotic species in FL waters. Throw a rock you'll hit 584 at least. Seriously. If it is a law its pretty useless.

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  2. Great post Rowan. We all live and learn. Hope this post will teach others.
    Tie, fish, write, conserve and photo on...

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  3. This essay is one of your most impressive and honest yet. Your personal evolution is inspiring.

    That an ecosystem is more important than one narrow-minded recreational activity is indeed true.

    On a personal note, while I grew up flyfishing (never often enough) with my father, I spent far far more time birding, hiking, sailing, canoeing and generally exploring the wilds both alone and with my family, especially my father. He was a true conservative. A member of the Nature Conservancy in its infancy, of Audubon, of the Natural Lands Trust. His only real prejudice was against non-native invasive birds. Especially the starling. But even he evolved. He had set up a have a heart trap to catch the overabundance of starlings. And he ended up training one. He was so impressed with the intelligence of that bird. It changed him some. He no longer hunted them as far as I remember.

    Your comment about the mink made me chuckle. When I discovered that we not only have wild mink here, but otters too, I was over the moon with joy. My reaction was precisely what you recommend--"a real wild ecosystem!" I've now found both species thriving on two different well known but beautiful streams in southern Connecticut. It is one of the things I look forward to sooo much--crossing paths with wildlife.

    While attempting to inculcate fly fishing in my own kids (your age) and I hear frustration, my comment is always, "it isn't the catching of fish. It is the possibility of catching fish and in so doing, enjoying nature in a focused way."

    The river otter:
    https://youtu.be/CXcrn1W0qvU
    And I caught perch right after that, haha!
    The next year:
    https://youtu.be/JlhP2T2fROg
    Caught trout in that same seam he just swam through.

    The mink:
    https://youtu.be/eDGx0vio1rs
    Never been a shortage of wild native fish in there (redfin, redbreast, fallfish, perch, dace, and some fish I couldn't identify).

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    1. Thank you.
      Your father sounds like someone I would have gotten along well with.

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    2. Yes, I think you would have liked him. He would certainly have fished with you.

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  4. I agree with 98% of what you had to say. However, I think the seals are having a greater impact than is perceived. We, HUMANS, have changed the ecosystem to a point where it is never going to bounce back to when we were not present, IMO. The predators of seals have dwindled to such a low number that there may be a need for the top predator, humans, to balance out the ecosystem. I think the same could be said about other mammals you touched upon. I don't think there is a right answer but we have screwed things up beyond repair and may need to be part of the solution.

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    1. You are demonstrating what is call "shifting baseline syndrome". Current seal populations are large only in comparison to the last 100 years. "There is very little evidence that culling seals will increase fishery yields or provide positive effects on the local ecosystem."-David Johnston, Duke U. I need numbers, and right now the best data shows that humans are having a serious impact on striped bass. That should be fixed first and foremost. If in 4 or 5 or 10 years, great whites aren't doing what they currently are (exploding in numbers and eating a lot of seals, as any apex predator does when a prey source population exhibits rapid growth in a small area) and the data shows that seals are having a disproportionate impact on certain fish, then it would be time to cull. But any calls to do so now are simply not backed up with solid data. As for the other mammals I mentioned, they all have non-human predators, I've seen no evidence any of them are overpopulated in this region, and they simply don't kill fish in the way anglers believe they do. Beyond that, "they eat our stocked trout" is just a horrible reason to kill an animal. Like hunters calling for open season on apex predators in areas where chronic wasting disease is effecting overcrowded ungulate herds, I see no convincing arguments for the culling of seals, mink, or otters.

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  5. Thanks for the informative reply. Never heard of the "shifting baseline syndrome" but makes sense. Hopefully the great whites take care of the problem.

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    1. The should. Beach goers will have to get used to the Cape being their domain once again, of course.

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  6. Great post Rowan. I appreciate that you recognize your own perspective changed. We're all learning together and I'm learning so much from your experiences and observations.

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