Invasive Species: Biting Back

The world’s aquatic ecosystems are suffering from overfishing.  Simply put, overfishing occurs when fish are caught faster than they can reproduce and replenish their populations.  While total global catch from wild fish stocks has leveled off over the past 10 years, this amount of capture remains at an unsustainable level. Popular species such as the Bluefin tuna, Atlantic cod, and red snapper are currently listed on the overfished list according to a 2018 NOAA Fisheries report[1].  There have been steps taken to reverse the trend.  Production from aquaculture, the practice of raising fish and crustaceans in a controlled environment, now nearly equals production from wild fish populations.  However, intensive aquaculture also has its drawbacks.  It destroys natural habitats and releases excess nutrients, causing harmful algal blooms nearby.  We need to look for alternative ways of producing sustainable seafood.


Invasive Delicacies

Invasive species can be any species not naturally occurring in an area.  These species typically have no natural predators, reproduce effectively, prey on native populations, and alter community food webs.  There are both federal and state programs to curb populations of invasive species, but many times the populations are too large or distribution too wide for these programs to be effective.  If you can’t beat ‘em, eat ‘em. Creating more economically-viable markets through policy incentives takes a bite out of the environmental problem while creating more sustainable seafood.


Case 1 – Lionfish

Take lionfish for example.  High in Omega 3 fatty acids and low in mercury, the invasive delicacy is caught by  both environmentally-conscious residents and commercial divers throughout Florida[2].  Florida has relaxed regulations on spearfishing, such as allowing harvesters of lionfish to spearfish in previously prohibited areas, and a simple $50 license is the only requirement to sell the fish in-state[3].


The price of lionfish in Florida can range from $3-$5 per pound, and Whole Foods even sold fillets in their South Florida stores for a limited time at $6.99/lb.[4] (for comparison, grouper can be up to $18/lb., and snapper from $8-$18/lb., depending on species and location).  The price of lionfish rises as you travel further up the East Coast; $18/lb. in Texas, and up to $35/lb. in New York[5].  The national demand far surpasses the local demand within Florida.  However, out-of-state distributors are not able to source enough lionfish to fill these larger orders.


There are many barriers encountered when selling lionfish out-of-state.  First off, an expensive statewide commercial wholesale license is required, which is not economically viable for an individual diver to purchase.  Secondly, the average catch per diver is small, and established seafood processors do not readily accept such small quantities.  Lastly, if a processor is willing to accept lionfish, many times the distance discourages divers from delivering their small catch.  While it is possible to catch hundreds of pounds of lionfish per day, the majority of divers do not do this.  The gaps in the supply chain restrict lionfish from becoming a nationwide sustainable seafood, and state policies to remove the barriers associated with out-of-state sale will spur greater development of the supply chain.  These could include allowing lionfish to be sold without a wholesale license or incentivizing processors to accept smaller quantities of lionfish.


Case 2 – Asian Carp

The Asian carp is hated by residents of Mississippi River Basin and beyond.  Carp were introduced in the United States to control algae blooms and aquatic vegetation, but quickly spread through floods and accidental releases[6].  Now, their abundant populations out-compete native fish, crustaceans, and mollusks for the same food sources.  Millions of dollars have been spent on federal programs to control the spread.


Similar to lionfish, Asian carp are high in Omega 3 fatty acids and low in mercury.  Although demand from restaurants and domestic markets remains high, there is a stigma against carp, as it is seen as a “trash fish”[7].  Subsequently, much of the harvested Asian carp is used to produce fertilizers and animal feed.  Even so, Fin Gourmet, a fish processor in Kentucky, is shipping over 20,000 pounds of fillets weekly to restaurants in Louisville, Chicago, New Orleans, and Las Vegas[8].  Some chefs are paying up to $10/lb.


In response, some states provide incentives to fishermen.  Kentucky pays an extra 5-cents per pound to fishermen, hoping to incentivize the removal of 20 million pounds over 5 years.  The Tennessee Wildlife Resources Agency (TWRA) is providing over $500,000 in funding to develop the Asian carp market beyond fertilizer.  The federal government, in combination with the two states, is developing and testing sound barrier technology to prevent carp movement[9]. These policies will take pressure off native stocks of catfish and bass while further developing the Asian carp market.


Going Forward

Sadly, humans excel at exploiting resources.  While dangerous with wild stocks, exploitation is one way to solve the problem of invasive species.  Lionfish and Asian carp are just two examples of healthy invasive species with high market potential.  Future state and federal policies should be directed at developing these markets and incentivizing their catch, rather than spending hundreds of millions of dollars on control technologies and culling programs.  Success in this area will save taxpayers money, take pressure off wild fish stocks, and spur greater harvests of invasive species.



[1]NOAA Fisheries, “Fishery Stock Status Updates”,,

(September 30, 2018)


[2]Andy Lowe, “6 Reasons to Eat Lionfish”,, (March 27, 2017)


[3]Jim Waymer, “Florida Lionfish Ban Takes Effect Aug. 1”,, (June 18, 2014)


[4]Whole Foods Market, “Take a Bite out of Lionfish: Whole Lionfish on Sale”,, (February 2017)


[5]Robin D. Schatz, “Let Them Eat Lionfish: A N.Y. Restauranteur Urges Diners to Prey on an Invasive Species”,, (December 21, 2015)


[6]U.S. Fish and Wildlife Service, “Asian Carp Facts Sheet”,, (2011)


[7]Tony Briscoe, “’Carp Cowboys’ round up invasive Asian carp as Illinois, federal officials debate costly measures to protect Lake Michigan,, (December 6, 2018)


[8]Jere Downs, “Asian Carp Leaps onto Restaurant Tables”,, (September 27, 2016)


[9]Jay Shah, “As Asian Carp Invade Tennessee, The State Asks Fishermen to Help Fight Back”,, (July 30, 2018)


9 thoughts on “Invasive Species: Biting Back

  1. This approach is thoughtful and would provide a unique opportunity to increase our fish stocks and supply through alleviating the pressure of invasive predatory species on native fish stocks and providing the invasive species as supply for the market. I think this approach would be effective depending on the structuring of the policy incentives and the marketing of the “trash fish,” considering that there are many examples of improper labeling of fish species in American markets. However, as you note that humans excel at exploiting resources, I would worry about what comes next if this approach is successful and invasive fish species such as the Lionfish and the Asian Carp are driven out. How would we ensure that native fish stocks recover and are not subsequently overfished once again? There may be similar lessons the American fishing industry can learn from other countries which have attempted to eat invasive species since we can’t beat them with other measures, like the example of the Amazonian paiche ‘invading’ Bolivian waters.

  2. This is a creative and unique way to mitigate two very serious environmental problems with one policy proposal. I was especially surprised to read the extremely high selling price of lion fish in New York, indicating the unmet demand that potential fishermen can capitalize on. I think forwarding this proposal would hinge on educating fishermen on the benefits of fishing specifically for invasive species, as I am sure that many are unaware of the potential economic benefits and high-selling price of these exotic species. Giving fishermen potential incentives to fish invasives would surely help, but it may be unnecessary for species like the lion fish considering the market that already exists. In my opinion, focusing on eliminating the various market barriers that exist for these invasives (most of which seem very unnecessary) should be a priority. Overall, a fascinating read and I look forward to potential policy in the future addressing this opportunity.

  3. You take a unique approach to combatting the overfishing problem. Targeting populations of invasive species seems like a good approach if their fishing and sales are incentivized. I had never heard of this alternative to overfishing until reading your blog post, but it definitely seems reasonable. I wonder if these fish (lionfish and asian carp) were marketed as sustainable alternatives, whether their popularity would increase in America and political will might be able to make the first more accessible/easier to sell.
    My only concern is that these seems like a temporary solution to an extremely pressing problem that threatens the stability of ocean ecosystems. There definitely need to be other regulations and reduction protocols in place to reduce fishing along coastlines and it is unlikely that consumption of invasive will entirely satisfy the demand for fish. However, any solution that helps to alleviate stress placed on our fisheries is a move in the right direction.

  4. This blog was truly eye-opening to me, I did not know that “production from aquaculture, the practice of raising fish and crustaceans in a controlled environment, now nearly equals production from wild fish populations.” While I was shocked to learn so many horrible facts about fishing across the country, I was really interested in your solution. Invasive fish species have a unique benefit built into them; people will eat them! As long as we are destroying our resources by killing entire fish populations, we can at least also consume the invasive species that are harming the survivors. I would like to know how politically and environmentally feasible you believe your solution is. I could see this proposal facing major backlash from those who want to stop people from buying fish in the first place. In other words, should we be focused on selling invasives at grocery stores in conjunction with everyday fish, or should we try to stop selling fish at all if we know we are depleting entire species?

  5. This blog was really interesting Nick! It is clear that you’re very passionate about the issues of invasive species and fisheries, as I also was able to see at Duke Blueprint this year when you tackled lionfish supply as well. I actually had learned a lot in high school on different invasive species and how to manage them as well, so your post really piqued my interest on using policy to seek those solutions. I think the solution of shifting funding from control techniques, that are ineffective against such widespread populations, to a strategy that is able to meet a seafood demand as well, is one with great potential. I imagine this proposed solution also has implications beyond the seafood market as well. For example, possibly using invasive plant species to create resources such as paper products or biofuels in order to both address their proliferation and other demands.

  6. You did a great job explaining how harvesting and consuming invasive fish species provides a win-win solution to help alleviate pressure on wild fish stocks and mitigate the damages of invasive species. I am particularly interested in the barriers that prevent invasive fish stocks from achieving a significant market share in the United States. You mentioned that the logistics of harvesting lionfish and the perception of carp as “trash fish” block the expansion of those particular examples. I wonder what techniques could overcome such barriers- perhaps government subsidized harvesting, fish branding campaigns, etc. Lastly, I would be careful in the suggestion that consuming invasive species provides a solution to the global fisheries crisis. While locally consuming invasive species will reduce demand for wild fish, given the scale of global fisheries I believe this would have a small effect, especially seeing that the U.S.’s fisheries are some of the most well-managed in the world. I would argue, however, the invasive species could provide a way for the U.S. to cut down on its massive seafood trade deficit.

  7. This was an incredibly interesting blog post – well done! I am doing the marine science concentration for the ENV major and I had never heard of this potential solution for the overfishing problem. After reading this post I am newly inspired to look more into this idea to really understand it more, so thank you for that! This is truly one of the more unique solutions to the fishing problem that I have been exposed to. I think in principle, it is a fantastic idea. People want to eat fish, so they should eat the fish that are a nuisance. I do think that in practice there could be some major road bumps. For one, it is incredibly hard to change the public opinion about certain protein sources. This does not mean that we should stop trying, it only serves to provide an example of how this might be hard to implement effectively. I’m thinking mainly of your carp example, because as you said, people view it as a trash fish. An interesting way to change the public opinion and cause them to want to buy more fish like that is to make it “trendy” for lack of a better word. If chefs and restaurants start to sell it, people might catch on and start to buy it themselves. After all, oysters used to be seen as a “poor man’s food”. There is definitely hope. The only other critique I have is that this feels like a short-term solution. Are there studies on how much this would alleviate the pressure on the more popular fish industries? Would increasing the sale of lionfish and carp really decrease the overfishing pressure on more common and widely-accepted fish? Finally, my biggest question on this idea is what would happen if those industries then become overfished? If this really works, wouldn’t we start to see overfishing of these invasive species in their own native habitats? This blog post sparked a lot of questions within me, which is exciting. I think this conversation should definitely continue.

  8. When I hear invasive species, I typically think about the programs directed at trying to get rid of the species through regulated efforts. However, the market-based approach you outline here is an interesting alternative to controlling the populations of what are considered unwanted species populations. One of the biggest invasive species we have in Minnesota besides Asian Carp is the Zebra Mussel. There is a widespread campaign led by the MN DNR to control and prevent the spread of this species. Every time I bring my boat or jet skis to a different lake (of which there are many in Wisconsin and Minnesota), the trailer and hulls have to be inspected by either a DNR rep or volunteer. I do not think there is the same demand for zebra mussels as you talked about for carp and lionfish, which might explain why the DNR is simply pursuing an aggressive campaign to get rid of them altogether. It is an interesting comparison between different non-native species. Nice post!

  9. I had no idea that there is a developing market for invasive species as a food source! I’ve only ever heard of the lionfish discussed in a negative way so learning that it can benefit fish populations by providing us with a new meal was really interesting! This does make me wonder about what will happen if these markets are developed. If we reach the point that there is such strong demand for invasive species, what will happen if these populations become overfished? Because they are invasive species, ideally we would like to exterminate the populations in these places. But if there is the demand for them, will there be an attempt at repopulation? Will they be farm raised? Obviously, there is no way to know these answers, but it will be interesting to see the results!

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