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. 

If you enjoy what I'm doing here, please share and comment. It is increasingly difficult to maintain this blog under dwindling readership. What best keeps me going so is knowing that I am engaging people and getting them interested in different aspects of fly fishing, the natural world, and art. Follow, like on Facebook, share wherever, comment wherever. Also, consider supporting me on Patreon (link at the top of the bar to the right of your screen, on web version). Every little bit is appreciated! Thank you to my Patrons, Erin and Christopher, for supporting this blog.