Tag Archives: Pokedex

Butterfree vs. Cutiefly: Pokémon Competition (and we ain’t talking about battle)


In nature, there are a limited amount of resources and life is in constant pursuit of these resources. It is this pursuit which drives many interactions from predation to parasitism. But, what is a resource?

A resource is anything that is consumed by an organism to grow and maintain its life functions. Food is always a resource, as is water for land-dwelling organisms. However, a resource doesn’t always have to be literally consumed. Space is a vital resource, particularly for sessile, or immobile, organisms. In this instance, space is “consumed” when an organism occupies it and subsequently relinquished upon that individual’s death. Potential habitats such as hollowed logs or abandoned burrows also constitute resources to be consumed.

A resource may be in demand by one species or many species, but regardless only a select number of individuals can consume a resource at a time. When a resource is consumed, its availability to other individuals decreases. This is the crux of competition.


Competition simply describes situations where an individual or group of individuals reduces the availability of a resource to other individuals through either consumption of the shared resource or by directly interfering with other individual’s ability to access the resource.

Organisms compete for a range of shared resources from food, to shelter, to space, and these competitors play by brutal rules—last man standing wins. A far cry from the fictional faints of the Pokémon world…or not.

Just as they compete in battle, Pokémon also compete in nature without the safeguard of trainer referees to steer these confrontations away from more fatal outcomes.

A prime example of this struggle can be found with an unsuspecting duo—Cutiefly and Butterfree. While the Bee Fly and Butterfly Pokémon respectively give the appearance of being nothing more than polite pollinators, the two are engaged in a fierce fight for flowers:

Nectar and pollen are its favorite fare. In fields of flowers, it gets into skirmishes with Butterfree over food. (Cutiefly, Pokémon Ultra Sun)

Nectar from pretty flowers is its favorite food. In fields of flowers, it has heated battles with Cutiefly for territory. (Butterfree, Pokémon Ultra Moon)

This is an excellent example of interspecific competition, when individuals of different species compete for resources. In this case, the resource being competed for is nectar.

Interspecific competition regulates competing populations, often suppressing both from reaching population levels they would otherwise achieve in the absence of competitors. Suppose, a Cutiefly reaches a flower before a Butterfree. The nectar inside is consumed and while nectar is a renewable resource with time, for the time being the availability of nectar for all Cutiefly and Butterfree decreases. But, it is the Cutiefly population which reaps the benefits as another individual can maintain its life processes, ensuring that is population remains up. The inverse is true for the Butterfree population, where another individual is deprived of nectar and thus must seek another nectar source or die, lowering the Butterfree population.


These interactions can lead to situations where one competitor proves better at consuming the shared resource drives the lesser competitor to extinction. This is the competitive exclusion principle.

Coined by Garrett Hardin (1960), the competitive exclusion principle says that if two species are competing for a limited resource, the stronger competitor will drive the weaker to extinction. As put concisely by Hardin, “Complete competitors cannot coexist.”

This principle is derived from the findings of G. F. Gause. He conducted experiments with two species of paramecium, a type of microscopic organism that could live in petri dishes. Grow separately, the paramecium grew rapidly, limited only by the food available to them in their respective dishes. However, when Gause grew them in the same dish with the same amount of food, one species proliferated while the other died out.


Later experiments with other organisms found similar results. Fruit flies, mice, beetles, and plants; in every case only one competitor emerged victorious while the other died out.

Why does this happen?

Simply put, if one organism can more efficiently consume a resource and decrease its availability to its competitor, then the dominant species increases, while the population of the lesser competitor decreases. The gap widens over time, and soon a negative feedback loop forms where the more abundant the dominant competitor becomes, the fewer resources there are available to the ever-dwindling numbers of the lesser competitor, further leading to its population’s decline.

This indirect interference with the competing population is referred to as exploitative competition. But not all competition is conducted indirectly. Sometimes, a species must take matters into its own hands (or fins, claws, leaves, etc.) to ensure they do not end up on the wrong end of the competitive exclusion principle. This is called interference competition, or when direct antagonistic actions are taken against a competitor to procure a resource, or at the very least prevent it from fall into the competitor’s hands (or fins, claws, leaves, etc.). And Cutiefly and Butterfree’s actions are antagonistic to say the least.

Butterfree’s entry in Pokémon Ultra Moon speaks of “heated battles with Cutiefly for territory” and Cutiefly’s Pokémon Ultra Sun entry states “it gets into skirmishes with Butterfree over food” in the flower fields of Alola.


So, if complete competitors cannot coexist, is it only a matter of time until either Butterfree or Cutiefly drive the other to extinction on Alola?

Well, maybe not.

On the offset, Cutiefly appears to be the dominant competitor. It’s Pokémon Sun Pokédex entry says that it can sense auras and thus “identify which flowers are about to bloom.” This alone gives Cutiefly a significant advantage over Butterfree. Being able to visit flowers immediately in bloom not only allows Cutiefly to fulfill its nectar needs before Butterfree but lets Cutiefly avoid direct confrontations with its competitor, who has a literal competitive advantage bearing poisonous scales on its wings which according to its Pokémon Moon entry scatters over Pokémon who attack it. With Poison being a weakness of Fairy-Type Pokémon such as Cutiefly, these encounters could prove fatal for the Bee Fly Pokémon.

Indeed, these Pokémon are “complete competitors,” but they can coexist.

A peaceful coexistence can be achieved through niche partioning, the ecological equivalent of dividing your childhood bedroom in half with your annoying sibling so you do not kill each other. Niche partioning occurs when competing species coexist by either using different resources or continuing to use the shared resource but occupying different habitats either physically or temporally (i.e. are active at different times of the day or during different seasons).

A textbook example of niche partioning comes from a study conducted by Joseph Connell (1961) on two species of barnacle, Balanus and Chthamalus.

The two barnacles lived in the intertidal zone of an ocean cliffside where the shared resource is space. Connell found Balanus barnacles the better competitor, as they had heavier shells to withstand Chthamalus crowding and grew rapidly, faster so than their competitor. Additionally, these feisty crustaceans would edge themselves under Chthamalus shells and pry them from their spots!

How could Chthamalus barnacles persist under such competition? Well, for all their shell-shoving, Balanus were not too keen to dry land, unfortunate for a creature living in the intertidal zone. Thus, they were confined to the lower portions of the cliffside where water had a more constant presence.


However, Chthamalus were desiccation-resistant, and could survive low-tide conditions. So, they colonized the upper portions of the intertidal zone free of competition.

Chthamalus surely could have lived in the lower intertidal zone as well, its fundamental niche consisted of both areas. But competition from Balanus limited it to the upper zones, its realized niche.

Thus, they were able to coexist, in segregation perhaps, but at least no one is shoving anyone off a cliffside.

A similar peace can be achieved between Cutiefly and Butterfree as well.

Like Balanus, Cutiefly may be the dominant competitor with its aura-sensing abilities, but the Pokédex gives no indication that it would be able to gather nectar under rainy conditions. However, Butterfree’s does:

Water-repellent powder on its wings enables it to collect honey, even in the heaviest of rains. (Pokémon Silver Version)

Butterfree could easily harvest nectar during periods of rain in which it wouldn’t have to compete with Cutiefly, or better yet find a realized niche in areas of Alola more prone to rain such as Route 17 or Po Town where Cutiefly couldn’t achieve flight.

Competition is a fact of life, but it does not always have to end in extinction.

Accurate Pokédex Entries

Cutiefly, the Bee Fly Pokémon: Using its aura-sensing abilities, Cutiefly can identify which flowers are about to bloom, allowing them to gather nectar before Butterfree arrive to pester them. The two are engaged in interference competition over nectar.

Butterfree, the Butterfly Pokémon: To avoid competition with Cutiefly, Butterfree tend to cluster in areas where rain is common as their waterproof scales allow them to gather nectar in the heaviest storms. This niche partioning allows them to co-exist peacefully with Cutiefly.

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Works Cited and Further Readings

Connell, Joseph H. 1961. The influence of interspecific competition and other factors on the distribution of the barnacle Chthamalus Stellatus. Ecology 42:710-723.

Hardin, Garrett. 1960. The Competitive Exclusion Principle. Science 131:1292-1297.

Ricklefs, Robert E. 2008. The Economy of Nature. 6th Edition. W.H. Freeman and Company. New York, NY. pp. 328-345.

Mareanie and Toxapex: The Crown-of-Thorns Pokémon (Pokémon Eating Pokémon Part 1)


The sea in many ways is a curious contradiction, as it is simultaneously the womb of life and home to a fierce array of predators. It is both the source nourishment and great cruelty. Hidden underneath its beautiful foaming blue sheets are the most crafty and devious creatures ever to have been seen by men. Swarms of jellyfish dragging their forest of stinging needles through the ocean currents, packs of prehistoric sharks so fine-tuned for predation that they have gone relatively unchanged since their dinosaurs, as is a common theme with nature’s apex predators.

The Pokémon oceans are no safer. In place of jellyfish are hordes of Tentacruel who cause fish to scatter whenever to congregate (1). Sharpedo zip through the water upwards of 75 mph, slicing through hulls of ship and snaring any unfortunate prey in their razor teeth, appropriately earning the title of The Bully of the Sea (2).

But lurking just off the coast of Melemele Island in the Alola region is a particularly devious critter. The waters of Alola are host to a problematic set of predators commonly known as Mareanie and its evolved form, Toxapex. Classified as the Brutal Star Pokémon, Mareanie has an infamous reputation for feasting on Corsola.

It’s found crawling on beaches and seafloors. The coral that grows on Corsola’s head is as good as a five-star banquet to this Pokémon. (Pokémon Moon)

But this predation is not limited to mere words in a Pokédex. The Seventh Generation of Pokémon Games introduced a new mechanic known as SOS battles, in which, a wild Pokémon will call upon an additional “ally” Pokémon to aid it in battle if it’s health drops below 50%.


However, in the case of Corsola, on rare occasion a Mareanie will appear when it calls. But instead of attacking the trainer’s Pokémon, Mareanie will instead attack the very Corsola that called it to battle, in many cases even knocking out the poor Coral Pokémon. Furthermore, to the frustration of many gamers, this is the only way Mareanie can be obtained in the game.

But it terms of sheer brutality, its evolved form, Toxapex, takes the cake:

Toxapex crawls along the ocean floor on its 12 legs. It leaves a trail of Corsola bits scattered in its wake(Pokémon Sun)

Those attacked by Toxapex’s poison will suffer intense pain for three days and three nights. Post recovery, there will be some aftereffects(Pokémon Moon)


Toxapex, the Brutal Star Pokémon

While at first glance, these entries may seem like the typical Pokédex hyperbole, with a few word tweaks these could easily describe the real-life Acanthaster planci—the Crown-of-Thorns starfish.

Most common in the oceans of Australia, though distributed throughout Indo-Pacific waters, the Crown-of-Thorns starfish crawls along the sea floor in search of coral polyps which it primarily feeds on. Like its Alolan counterparts, the Crown-of Thorns starfish is a Poison-Type per say, as it is armed with an arsenal of toxins known as saponins. While we can only speculate on the aftereffects of Toxapex’s poisonous sting, in human, the crown-of-thorns sting can lead to a plethora of symptoms, including swelling around the site of entry, followed by a sharp sting that can last for hours, nausea, and bleeding (9). Indeed, there will be some aftereffects.

Just as Mareanie and Toxapex prey on Corsola, the Crown-of-Thorns starfish preys on coral, which, unlike the Pokémon Corsola, are sessile organisms. Considering how slow most starfish move, this is only to the Crown-of-Thorn’s advantage. Possessing as many as 21 tentacles (3), the starfish attaches itself to living coral colonies where it begins its feeding process. First, the starfish forces its stomach out of its mouth and onto the surface of the coral. It then releases digestive enzymes to break down the coral tissue. As the starfish retracts its stomach, it draws in the broken-down tissues, leaving a scar of white coral skeleton, often referred to as a “feeding scar” (4) .


“Feeding scar” on Australian coral reef from crown-of-thorns starfish.

While not as brutal as Toxapex’s treatment of Corsola, the feeding habits of Acanthaster planci can have deleterious effects on coral colonies and coral reef ecosystems as a whole. Once a feeding scar has formed, surrounding algae will infest the wound, resulting in a crusty skeleton appearance (5). In most cases, the corals—while not in the best aesthetic state—continue to live, though with their vibrancy diminished. However, in this weakened state, some species of coral will crumble due to agitation from storms and other sources of rough waters. Moreover, in addition to invasions by filamentous algae, other organisms such as sponges and “soft corals” will move in on the feeding scars. Gradually, this cascades into an environmental shift in which surfaces where hard coral polyps would take hold are occupied by the invaders. This, in effect, deprives many fish and marine herbivores of their habitat and food sources (6).

Now consider the following PokéDex from Pokémon Sapphire Version:

“Clusters of Corsola congregate in warm seas where they serve as ideal hiding places for smaller Pokémon.” – Pokémon Sapphire Version

Perhaps a similar effect is found in Alola as a result of Mareanie/Toxapex’s predation of Corsola. This would explain Corsola’s rare encounter rate, as well as other Pokémon supposedly endemic to Alola.

Additionally, starfish populations are on the rise. Currently, the exact cause for this spike in population is unknown. Some proposed hypotheses include the depletion of natural predators due to overfishing, rising sea temperatures enhancing the development of larvae, or that simply these observed outbreaks are no more than an aggregate of starfish having previously consumed all adjacent coral colonies and thus cluster together in a single area. Regardless of the cause, the impact of these creatures remains severe, as a study of the Great Barrier Reef revealed that over a 27-year-long period, in a survey of 214 coral reefs, the reef suffered a 50.7% loss of initial coral cover (7). The damage was attributed to three main causes—tropical storms, coral bleaching, and the crown-of-thorns starfish. The starfish alone were responsible for 42% of the total coral loss.

However, there is hope. Recently, researchers have discovered a means of controlling these seemingly invincible organisms. A single, careful, injection of household vinegar into the tentacle of a crown-of-thorns starfish can render the starfish lifeless within 48 hours (8). While the death of any creature—even one that is quite a nuisance—is unfortunate, it is the hope of conservationist and environmental agencies alike that this new treatment will spare the last of the world’s reefs from the wrath of the Crown-O-Thorns.

Perhaps a similar method could be employed on the Mareanie of Alola.

Of course, you would have to find one first.

A suggestion. If you stumble across a Mareanie, don’t faint it, either with Pokémon or your mother’s vinegar.


Accurate Pokédex Entry (Mareanie): In Alola, much of the Corsola loss in recent years can be attributed to a spike in Mareanie populations. However, scientists have found that injections of household vinegar might be used to control their growing population.

Accurate Pokédex Entry (Toxapex): No one knows for sure why its numbers are on the rise. One hypothesis is that overfishing has depleted the oceans of Alola of Toxapex’s natural enemies, allowing the Brutal Star Pokémon to proliferate unchecked, leaving Corsola everywhere scarred and crumbling.


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Works Cited

  1. Game Freak. Pokémon Moon.Nintendo, 2016. Nintendo 3DS.
  2. Game Freak. PokémonSun.Nintendo, 2016. Nintendo 3DS.
  3. Caso, M.J. (1974). “External morphology of Acanthasterplanci (Linnaeus)”. Journal of the Marine Biological Associataion of India16 (1): 83–93.
  4. Current Biology
  5. Belk, D (1975). “An observation of algal colonization on Acropora asperakilled by Acanthaster planci‘.”. Hydrobiologia46 (1): 29–32. doi:10.1007/bf00038724.
  6. Wilson, S K; Dolman, A M; Cheal, A J; Emslie, MJ Pratchett; et al. (2009). “Maintenance of fish diversity on disturbed coral reefs”. Coral reefs28(1): 3–14. doi:10.1007/s00338-008-0431-2.
  7. De’ath, G. et al. 2012. The 27–year decline of coral cover on the Great Barrier Reef and its causes. PNAS109:17995-17999.
  8. Boström-Einarsson, L. & Rivera-Posada, J. Coral Reefs (2016) 35: 223. doi:10.1007/s00338-015-1351-6
  9. Birkelandand Lucas (1990). Acanthaster planci: Major Management Problem of Coral Reefs. CRC Press. pp. 131–132. ISBN 0-8493-6599-6.


Pokémon Eating Pokémon: Do Pokémon Eat Each Other? (Introduction)

Pokemon eating pokemon

“We are not afraid of predators, we’re transfixed by them, prone to weave stories and fables and chatter endlessly about them, because fascination creates preparedness, and preparedness, survival.” – E. O. Wilson

One of the most fundamental relationships in nature is that between predator and prey, otherwise known as predation. In simple terms, predation involves the consumption of one organism (prey) by another (predator). The interactions between predator and prey have fueled an evolutionary arms race, as predation is one of natural selection’s favorite tools for shaping life. The struggle for life has forged the vast biodiversity we see today—from the pyrotechnics of the bombardier beetles, to the assemblage of potent toxins of the Portuguese Man-O-War, to the breakneck dives of the Peregrine Falcon, life continues to push the limits of possibility to fulfill its ultimate biological purpose—to adapt, scatter, and survive.

The mandate of life to propagate itself has led to what many critics of evolutionary theory would consider a dark and grim world, a world governed by the Darwinian aphorism “Survival of the fittest”, a world where this concept is applied in all aspects of life, natural and social. It is with this portrait of the natural world that they postulate a greater purpose, and from that greater purpose they claim it is only reasonable to expect a greater hand guiding these dynamic interactions.

However, to view the dance between predator and prey as an unfortunate side effect of early man’s follies is to ignore the beauty that has arisen from this eternal struggle. For if the day does come when the wolf shall live with the lamb, it will surely herald the demise of life forever. A stagnant ecosystem is a dead ecosystem. The day where packs of wolves no longer chase down lambs will be a sign onto which this grand hand has dealt the final blow to his creation.

Just as the occasional conflagration is needed to clear the overgrown forest, predation and its, at times, heart wrenching cruelty, is necessary for the continuation of life.

As with many aspects of the natural world, this necessity extends onto the fictional universe of Pokémon. As discussed in previous entries, the Pokémon World is no stranger to interspecies interactions. Parasitism is alive and well in Parasect, a Pokémon who upon evolution has its mind and bodily autonomy hijacked by a parasitic mushroom on its back, an obvious illusion to the real-life Corydceps, a genus of fungi most notably featured in the Naughty Dog’s hit game The Last of Us. In Slowbro and Shellder—Mutualism, Commensalism, or Parasitism, I argued that Slowbro benefited from a mutualistic symbiotic relationship with Shellder. Perhaps the most obvious interaction between Pokémon is the trainer-mediated engagement in nonconsequential battle—otherwise known as Pokémon Battles. However, these interactions, for the most part, do not influence the greater ecosystem. Furthermore, all parties involved leave without substantial harm but without significant gain either.

Quite simply, Pokémon battles are ecologically meaningless encounters.

However, when Pokémon engage with each other outside of the mediation of a human-trainer referee, these encounters become far more interesting. The hands of evolution take shape and suddenly trivial encounters hold life and death in the balance, the tools of battle are wielded without restrain as Pokémon fights Pokémon with the intent of either walking away with their life intact or feasting on the corpse of their fallen opponent.

To answer the question posed by the title; yes, Pokémon do eat other Pokémon, though explicit details of these interactions are scarce at best or left in vague ambiguity. For the purposes of this survey, with two notable exceptions, only entries which explicitly cite Poké Predation will be considered a true predator-prey relationship. Indeed, the Pokédex is rife with mentions of Pokémon chasing and consuming an unidentified “prey”, but since the question of whether animals exist in addition to Pokémon in this fictional world is yet unanswered definitively, for the sake of simplicity we will limit our inquiry to those we are sure prey on their fellow Pokémon. But make no mistake, even with this criterion, the Pokédex is abundant yet with tales of fierce predation, many of which have appeared already on numerous creepy Pokédex entries lists. However, this survey of Poké Predators will illuminate new entries and Pokémon precisely skimmed over and deepen our understanding and appreciation for the complexity of this world and our own.

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Is Magikarp an Invasive Species?

I Love Magikarp

Totally pathetic, unreliable.

These are the first words used to describe the lowly Fish Pokémon in The Magikarp Song. And while the song is ultimately an ironic ode to the oft-mocked Pokémon peppered with tongue-in-cheek jabs at the fish, one only need take a cursory glance at Magikarp’s Pokédex history to gain a sense that the scientific community—or whoever authors these fantastical entries—does not particularly hold Magikarp in the highest esteem:

In the distant past, it was somewhat stronger than the horribly weak descendants that exist today. (Pokémon Red and Blue Versions)

An underpowered, pathetic Pokémon. It may jump high on rare occasions, but never more than seven feet. (Pokémon Gold Version)

This weak and pathetic Pokémon gets easily pushed along rivers when there are strong currents. (Pokémon Crystal Version)

Magikarp is a pathetic excuse for a Pokémon that is only capable of flopping and splashing. This behavior prompted scientists to undertake research into it. (Pokémon Ruby Version)

It is virtually worthless in terms of both power and speed. It is the most weak and pathetic Pokémon in the world. (Pokémon FireRed Version)

It is said to be the world’s weakest Pokémon. No one knows why it has managed to survive. (Pokémon Diamond Version)

Many of the lighthearted lyrics of The Magikarp Song are lifted directly from the Pokédex, but only when read alone without the catchy tune playing in the background can one truly taste the venom seeping from the belittling and, honestly, slanderous text.

The main ethos of this blog is that just as there is something to be learned from every organism, so too there is also something to be learned from every Pokémon. And The Pokémon Games seem to have a similar message at their core—that all Pokémon, big or small, strong or weak, have something to offer. The immortalized words of Elite Four Karen speak to this truth:

Strong Pokémon. Weak Pokémon. That is only the selfish perception of people. Truly skilled trainers should try to win with their favorites. (Pokémon Silver, 2000)

Yet, the mockery of Magikarp throughout the Pokédex seems to contradict this central core message.

It was my original intent for this Pokémon Day, to write in defense of Magikarp. To extol its high fecundity and amazing osmoregulation, to applaud its persistence throughout the ages despite being “weak” and to explore the life history traits of Magikarp and the evolutionary trade-off that might have led to its current “weak” form—topics that I may cover in the future.

But, during my research, I came across several troubling traits in Magikarp that lead to a worrisome conclusion that might explain why the Pokédex displays such distain for the Fish Pokémon. Magikarp is an invasive species.

We’ve discussed invasive species previously regarding the Alolan forms of Rattata and Meowth (Alolan Rattata and The Feral Cat Problem), and it is now consensus opinion within the community that invasion is a key theme of the Generation VII games. Additionally, it could be argued that most, if not all Pokémon are invasive, or nonindigenous at the very least. However, I propose that Magikarp is not only invasive, but is having detrimental impacts on ecosystems all across the Pokémon World.


Is an Invasive by Any Other Name Just as Sweet?

You may have noticed I’ve been careful not to use invasive and nonindigenous interchangeably. Anyone whose been introduced to the topic before may be accustomed to one or both or any of the tens of terms used to describe nonindigenous species—alien, introduced, exotic, imported, naturalized, transient—the list continues for as long as there are papers written on the subject. This abundance of terms can lead and has led to much confusion about what exactly is being described. Is the discussion limited to only harmful organisms? Are benign organisms invasive? What counts as alien? Are humans the only vector by which these organisms can be introduced?

Even the most frequently used term “invasive” has found itself carrying differing definitions throughout the scientific literature where it has been used as:

  • A synonym for nonindigenous
  • An adjective for nonindigenous species that have invaded natural areas
  • A term used to distinguish between nonindigenous species established in cultivated habitats (i.e. domesticated farm animals) and those established in natural ones (i.e. “the wild”)
  • A term used to describe widespread nonindigenous species
  • A term used to describe widespread and harmful nonindigenous species

If multiple, differing definitions can be derived from a single term, the compounding effect of having tens of terms in use can lead to even more confusion for scientists and especially the public. Additionally, even if we limit ourselves to “invasive” problems can arise when discussing nonindigenous species as generalizations could easily lump together organisms that do not have comparable effects on their habitat.

Here’s an example. The common goldfish is considered invasive under two of the above definition as it is (1) nonindigenous to the United States, and (2) widespread through its invaded habitat since its introduced into American waterways thanks to neglectful fish owners. However, goldfish rarely achieve high enough densities to cause significant harm to their habitats. Contrast this with the zebra mussel, a textbook invasive species from Eurasia which has cleared waterways and clogged pipes throughout North America. The zebra mussel is both widespread and found at high enough densities to have adverse effects on its habitat. Both organisms are considered invasive, yet in a generalized discussion of invasive species they do not appear to be exhibiting the same phenomenon.


Naturalized goldfish (left). Zebra mussel infestation (right).

Furthermore, use of invasive terminology can lead to misleading conclusions about the organisms themselves. As Colautti and MacIsaac (2014), authors of the paper from which this article draws heavily from, point out, the use of this language reinforces the mistaken idea that invasive species are some type of taxonomic group, that their invasive qualities are intrinsic to their being, forgetting that all nonnative species are native somewhere.

“Indeed the very terms used to describe NIS are misnomers in that nonindigenous species are actually nonindigenous populations of species. In other words, the same ‘species’ that are nonindigenous, naturalized, or invasive in one area are native somewhere else.” (Colautti and MacIsaac 2014)

Thus, Colautti and MacIsaac devised a framework to better classify nonindigenous species using a more neutral terminology. This the framework from which I will work within for the duration of this article.

Colautti and MacIsaac conceptualize nonindigenous species, referred to as “propagules” (a piece of a plant that can be snipped and planted elsewhere to form a new plant), as advancing through five stages.

First is Stage 0—the potential propagules still reside in their native “donor” habitat. The propagules enter Stage I when they are first “snipped” from their native habitat and transported elsewhere. If the propagules survive transport and release into their new environment they enter Stage II. Once introduced, propagules may achieve Stage III where they are “numerically rare” but have the potential to further establish themselves. From here, propagules can enter two diverge paths into Stage IV—become widespread (Stage IVa) or become dominant (Stage IVb). Once an organism has become both widespread and dominant, they have entered Stage V—what most people and conservation organizations would consider “invasive”.


From Colautti and MacIsaac (2014)

This new framework allows for distinction between nonindigenous species of varying ecological influence. Let’s return to our previous example. Under this framework, the goldfish would be classified as Stage IVa (widespread), while the zebra mussel would be Stage V (widespread and dominant).

So where does Magikarp fit into this framework?


Magikarp—the Invasive Pokémon

There are currently no hard-and-solid predictors of whether any given species will become invasive if introduced into a novel environment, but there are a few general traits that most successful invaders tend to have. Firstly, successful invaders typically mature early and reproduce rapidly. In essence, they adopt the reproductive strategy of freaking a lot, freaking early (censored for your children’s viewing). Additionally, good invasive species have high dispersal rates—are good at getting their offspring out into the further reaches of their habitat to become widespread and check off one box towards becoming a Stage V species.

Another good trait to have is being able to adapt to a wide range of environmental conditions. They are often tolerant of adverse conditions that other organisms would typically not thrive in, such as anoxic (low oxygen) or heavily polluted habitats. This adaptability can be achieved sometimes through phenotypic plasticity, when outward expression of certain traits changes depending on the environment (we talked more about this in Eeveelution Epigenetics). Successful invaders are also usually generalist, being able to consume a wide range of food sources and adapt to whatever happens to be lying around in their environment.

Lastly, most invasive species have an association with one species in particular—homo sapiens.

Humans introduce a lot of nonindigenous species to foreign environments. A review of nonindigenous species in the United States estimates 50,000 nonindigenous species in the US costing $137 billion annually in damages and loss of recreational value (Pimentel et al. 2000). Most are benign and are intentionally brought over, such as domesticated farm animals like dairy cows and chickens. Many are imported as pets, like the Burmese python which now infamously ravages the Florida Everglades. Others hitch a ride unintentionally, such as the zebra mussel which stowed away in the ballasts of cargo ships. As a rule of thumb, only 10% of introduced organisms will become invasive—only 4,500 of the 50,000-nonindigenous species in the US are considered invasive. This may explain why in regions abundant with nonindigenous Pokémon, only a few become invasive like Magikarp.

And Magikarp does appear to possess quite a few invasive qualities.

For starters, Magikarp seems to have fully adopted the freak-a-lot-freaking-early lifestyle. In game, Magikarp and Gyarados require the fewest egg cycles to hatch—indicative of a fast and early maturity. Additionally, the Pokédex entry for Pokémon Sun suggests Magikarp is also a rapid reproducer:

Although weak and helpless, this Pokémon is incredibly fertile. They exist in such  multitudes, you’ll soon grow tired of seeing them. (Pokémon Sun)

Pokémon Ultra Moon states that Magikarp can be found in “waters all over the world!” and this mostly rings true as Magikarp is present in every regional Pokédex except for Unova—possibly due to stricter regulations on introducing nonindigenous species since it is a US-based region. All of this would suggest high dispersal capabilities in reproducing Magikarp.

Furthermore, Magikarp displays a high tolerance across a wide range of environmental conditions. From the cold lakes of Sinnoh, to the polluted waters of Celadon City in Kanto, and the sunny shores of Alola, Magikarp thrives. Its entry from Ultra Moon speaks to this:

Thanks to their strong hold on life, dirty water doesn’t bother them at all. They live in waters all over the world! (Pokémon Ultra Moon)

Magikarp even exhibits some form of phenotypic plasticity in its ability to switch from fresh to saltwater, as Pokémon Yellow states, “It can be found swimming in seas, lakes, rivers, and shallow puddles.”

Most importantly, Magikarp has a close association with humans in the Pokémon World. In Kanto, and even strictly regulated Unova, Magikarp are sold as pets, similar to goldfish, a species of Asian carp which serves as the inspiration for Magikarp. In fact, this is a likely scenario for its introduction through the waters of the world. Tourists bought these Pokémon as pets while on vacation in Kanto and release them upon their return to their native region, as is the case with many exotic pets. Another possibility is that Magikarp was exported from its assumed native habitat of Kanto for the purposes of aquaculture else, just as several species of Asian carp were introduced into the US and Europe as foodfishes.

So where does this leave Magikarp under the framework established earlier by Colautti and MacIsaac? Well, by the evidence presented thus far, Magikarp is at least in Stage IV. Specifically, we know Magikarp is widespread (IVa). But is it dominant?

Dominance, in ecology, refers to how much biomass an organism constitutes in comparison to its competitors. In simplest terms, dominance depends on who is most numerous.

We obviously lack population data on Pokémon, so we’ll have to make do with what information we do possess—where each Pokémon can be found. I’ve taken all the fish Pokémon of each region where Magikarp can be found and compared the percent of the total region’s locations (routes, cities/towns, landmarks) that each Pokémon could be found in. And the results are not hopeful.

In Kanto, the presumed home range of Magikarp, there are only five “fish” Pokémon—Magikarp, Goldeen, Seaking, Horsea, and Seadra (yes, seahorses are fish). Of these five, two display dominance—Goldeen who can be found in 45% of locations, and Magikarp who covers 50% of Kanto. This shared dominance is to be expected in its native habitat, and further supports Kanto as being its native region


But in foreign regions, Magikarp truly makes a Splash.

In Hoenn, Magikarp competes with thirteen other fishes yet is present in 43% of locations. The closest competitor is Sharpedo at 15%, almost three times less than that of Magikarp. This trend holds for Sinnoh too, with Magikarp in 46% of locations. Native fishes like Finneon and Lumineon only have 10% coverage each. Kalos is a bit of an outlier, as it’s the only region with a pretty even distribution of fishes. There is no dominant fish and the fish with the greatest coverage is Luvdisc at 10%, greater than Magikarp in this region. This may be due in part to the massive richness found in Kalos—home to 24 different fish Pokémon, the most of any region. The greater competitions could perhaps damper the effects of Magikarp encroachment onto foreign territory.


However, in Alola, Magikarp is dominant once again with 30% coverage across these tony islands, outcompeting even Wishiwashi (17%). Furthermore, when compared with another widespread nonindigenous species who happens to be found all the same regions—Goldeen—Magikarp was found to have significantly greater coverage still.


So it does appear that Magikarp is at Stage V in at least three separate regions of the Pokémon World. But what impacts could Magikarp have on its invaded habitats.


Malicious Magikarp

Nonindigenous fishes in the US cost an estimated $1 billion annually in damages and losses. Introduced carp in particular have become a notable nuisance in American waterways. Asian carp have been known to leap up to 10 feet from the water when water motorists disturb their schools. In 2015, one man had his nose fractured and brow bones shattered by a leaping carp while inner tubbing on the Mississippi River.

An underpowered and pathetic Pokémon indeed.

Moreover, invasive carps can have devastating impacts on ecosystems. Asian carp decrease the amount of suspended vegetation in waterways and often deplete communities of benthic macroinvertebrates (Matsuzaki et al. 2009), organisms vital in the leaf breakdown process and export of organic materials and nutrients to downstream systems. Additionally, carp increases ammonium concentrations which can lead to algal blooms and subsequent anoxic conditions. Even in small numbers carp can be responsible for the deterioration of entire ecosystems. Bayer et al. (2009) found that when even carp biomass was 3-4 times lower than what is typically found in invaded systems, these fishes can reduce vegetation cover by 50%, halving waterfowl abundance in the process—all within the span of 7 years.

Further increases in carp left only 17% of the original surface vegetation and reduced waterfowl abundances to a slim 10% of original numbers.

If Magikarp is wreaking havoc anywhere near the scale of real-life carp, then the animus which Pokédex authors feel toward the Fish Pokémon is understandable—but ultimately misguided.

It is important in these discussions about invasive species to remember not to conflate the invasion of the species and the damage it does with the species itself. There are no “bad” animals just like there are no “bad” Pokémon, only bad humans who allow them to do bad things.

There is nothing intrinsically wrong with these organisms, they are just really good at doing what they do. Zebra mussels are really good at filtering water. Carp are really good at consuming vegetation. These traits would otherwise serve them well in the appropriate environment, and they serve really well in novel ones. It just happens that in these novel environments, their superb niche fulfillment happens to be detrimental to all other biota within the vicinity.

We must separate the damage from the organism and take a look in the mirror because you could say we are the most destructive invasive species—having conquered every continent and left our footprint on almost every habitat.

83% of terrestrial land is affected by human activity, and we’ve put to use 98% of Earth’s farmable land (Sanderson et al. 2002). Where oceans and mountains blocked the spread of potential invaders, humans provided a ferry, a bridge to novel worlds and novel niches. We were their vector into worlds unknown. And we are still reaping what we have sown.

So spare Magikarp your hate.

Because you’re totally pathetic, unreliable.

Happy Pokémon Day.


Accurate Pokédex Entry: A popular Kanto pet, Magikarp has since been introduced to waters all over the world! However, its rapid reproduction and high tolerance for polluted waters has allowed it to spread into almost every aquatic habitat and has become the dominant fish Pokémon in many regions, outcompeting even native species.

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Works Cited

Bajer, P., G. Sullivan, and P. Sorensen. 2009. Effects of a rapidly increasing population of common carp on vegetative cover and waterfowl in a recently restored Midwestern shallow lake. Hydrobiologia 632:235-245.

Colautti, R. I. and H. J. MacIsaac. 2014. A neutral terminology to define ‘invasive’ species. Diversity and Distributions 10:135-141.

Matsuzaki, S., N. Usio, N. Takamura, and I. Washitani. 2009. Contrasting impacts of invasive engineers on freshwater ecosystems: an experiment and meta-analysis. Oecologia 158:673-686.

Pimentel, D., L. Lach, R. Zuniga, and D. Morrison. 2000. Environmental and Economic Costs of Nonindigenous Species in the United States. BioScience 50:53-65.

Schankman, Paul. 31 Aug 2015. Pleasant Hill man injured by flying Asian carp. Fox 2 now St. Louis. http://fox2now.com/2015/08/31/pleasant-hill-man-injured-by-flying-asian-carp/. Accessed 20 Feb 2018.