Friends or Foes (part 1)

Hi everyone! Before I begin, I would like to ask you a question! When you hear the term “invasive species”, what comes across your mind? Well as for me, I think of a dangerous, aggressive and foreign animal.

My bias shows in my introductory blog post. Dr Coleman pointed it out and commented that invasive species can be native too. This is true when factors that deter them from overproducing and outcompeting resources are removed (Southern IPM Center, 2010).

A quick google search on invasive species will show a clear prejudice against them…

Screenshot of a google search on invasive species

Let us throw away our bias and foster a more objective and fair judgement towards invasive species. Do they deserve such a harsh reputation?

Invasive species are Bad

A conventional perspective is that their presence contributes to biodiversity loss. Native species are endangered due to the absence of predators to regulate invasive species population and along with invaders’ ability to modify their environment to suit their needs, this allows them to colonise the place (NWF, date unknown).

Photo of a Burmese Python © Skeeze

It is published that the loss accrued, from the implications of invasive species, is greater than $120 billion annually in the United States (FWS, 2012). Before-mentioned costs are accumulated from the mitigation of the spread of invasive species, restoration of endangered species, damages to infrastructures and decreased agricultural productivity (FWS, 2012). With a concerning loss in a capitalist society, no wonder invasive species are usually demonized.
One example is the Burmese pythons (it is one of the 4 species I drew in the header!), originally from South East Asia and was introduced into the United States as exotic pets (Lower, Shaul, Shaul and Weaver, 2018). Many buyers were unaware of the potential size they can grow to and irresponsibly released them into Florida’s Everglades (Lower, Shaul, Shaul and Weaver, 2018). Burmese pythons are flourishing in Florida because of the absence of predators and their ability to open their jaws broadly allows them to consume preys of varying sizes (Lower, Shaul, Shaul and Weaver, 2018). Their jaws enabled them to eat up an animal as big as an American crocodile (Lower, Shaul, Shaul and Weaver, 2018)!

Ecological balance is disrupted, threatening native wildlife. To counteract the ecological imbalance, over 2 decades, the government of Florida has allocated $101.2 million and $1.4 million on the restoration of Wood stork and Largo woodrat respectively (FWS, 2012).

With that in the next post, I’ll cover the positive sides of invasive species. Stay tuned!

References

Southern IPM Center, 2010, Can an native species become invasive? retrieved from

https://ipmsouth.com/2010/11/23/can-native-species-become-invasive/ 

National Wildlife Federation, Invasive species, retrieved from

https://www.nwf.org/Educational-Resources/Wildlife-Guide/Threats-to-Wildlife/Invasive-Species

FWS, 2012, The Cost of Invasive Species, retrieved from

https://www.fws.gov/verobeach/PythonPDF/CostofInvasivesFactSheet.pdf

Lower, E., Shaul, T., Shaul, K. and Weaver, E., 2018. 1.4 Invasive Species Burmese Python (Python Bivittatus) And Its Effect In Florida. [online] Ohiostate.pressbooks.pub. Available at: <https://ohiostate.pressbooks.pub/sciencebitesvolume2/chapter/1-4-invasive-species-burmese-python-python-bivittatus-and-its-effect-in-florida/#:~:text=Burmese%20pythons%20are%20having%20a,apex%20predator%20in%20the%20area.&text=Therefore%2C%20the%20population%20of%20these%20snakes%20is%20not%20being%20naturally%20controlled.> [Accessed 10 September 2020].

11 comments

  1. triciatay · September 12, 2020 at 4:32 pm ·

    Hi Lixuan!
    Interesting post regarding the implications of invasive species. Before reading your post, I’ve only known about the threat they pose to native wildlife. Hence, the economic implications were really insightful!
    The point you made about Burmese Pythons ending up as invasive species due to irresponsible buyers reminded me of how Red-eared Sliders became an invasive species in Singapore too. I guess a contributing factor would be how little pet shops educate potential owners (e.g. purchasing a correct cage/tank size)?

    • glixuan · September 14, 2020 at 4:12 am ·

      Hi Tricia!
      I’m glad this post has widened your perspective!
      Yes, that is true! I agree that it is critical to educate and provide buyers with accurate information. Prevention would greatly mitigate the spread of invasive species.
      Thankfully there are increasing sources on invasive species, you can refer to this link for more info! – https://www.invasivespeciesinfo.gov/subject/education-and-outreach
      Plus, not only is it detrimental for the environment, but it is also cruel for the animals as they’re used to the protected environment provided by humans. Releasing them into the wild exposes them to the ruthless elements of nature that they’re foreign to, thus they often end up dying…
      Lixuan

      • ENV3102 · September 16, 2020 at 2:08 pm ·

        Hi Lixuan,
        If it were true that being released into the wild constitutes cruelty to the released animals, how do you explain the amazing, global success of red-eared sliders wherever they’ve been introduced ?
        Meaning, isn’t the harm being done to the ecosystem ?
        Thanks,
        jc

        • glixuan · September 17, 2020 at 11:25 pm ·

          Hi Dr Coleman!
          It is a case by case basis, depending on the context. In the case of Red-eared sliders, they possess characteristics like high reproductive rate, big size, diverse diet and aggressive nature. Coupled with their adaptability to a large variety of aquatic environment, they can quickly colonise their new environment. Whereas others fail to adapt to the new conditions and die.
          But what I wanted to express was that regardless of whether or not releasing exotic pets into the wild pose a danger to the ecosystem, it is just irresponsible to release exotic pets into the wild.

          references
          Mara Pendergrass, 2002 retrieved from http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Red-eared%20Slider%20Turtle.html

  2. Li Zhe · September 14, 2020 at 4:11 pm ·

    Hi Li Xuan, I love your blog cover photo. Personally speaking, I find invasive species to generally deserve their label. As if species is alien and does not cause any harm to its new ecosystem, it would generally be called non-native. If it does indeed harm its new environment, then it will be labelled invasive or if they are unable to compete they would simply die out. I think it is interesting to note that the invasiveness of a species also should be contextualized depending on its new environment. I was wondering if you have any thought on this?

  3. Li Zhe · September 14, 2020 at 4:14 pm ·

    http://www.iucngisd.org/gisd/
    heres a website pretty interesting for invasive species i found it while writing about invasive species for drongo blog 🙂 hope it helps dun reply this pls ahahah

  4. Christabel · September 14, 2020 at 5:42 pm ·

    Hi Lixuan!
    Very interesting post, the sheer amount of money that invasive species can cost governments really shocked me! I have to confess that I also contributed to this problem when I was very young, and I feel very bad about now :(. It might be hard to impose regulations and fines because unless the person is caught in the act, it can be easy for people to get away with it. What are your thoughts on this? Thank you and I’m looking forward to your next post!

    • glixuan · September 15, 2020 at 1:17 am ·

      Hi Christabel!
      It’s okay as we grow we learn! And you’re not alone, I am equally guilty of that…
      Yeah, and there are high compliance costs as inspectors need to frequently and thoroughly conduct checks to ensure the law is being adhered to. I believe that provision of information like campaigns, public education and advertisements would be better as it directly addresses the root of the problem – ignorance. Furthermore, they’d not carry out such irresponsible acts because they’re aware of the potential risks and consequences and not just because of the fear of getting fined a hefty sum.
      Lixuan

  5. just2 · September 14, 2020 at 9:40 pm ·

    I’m not going to lie, I am biased towards snakes so learning that my favourite snakes, the pythons, are an invasive species does make me a little sad. I love the drawing by the way, Li Xuan!
    I would like to ask, how long does it take to determine if a species is invasive? Could I also ask for your opinion if it takes too long?

    • glixuan · September 16, 2020 at 12:27 am ·

      Hi Justin!
      Oh no… that’s sad but it’s always fun to learn more things about your favourites, am I right! I appreciate it, thank you so much!
      There is a “wait and see” method which only tends to be applied when there is high uncertainty in species spread so that if invasion ends up not damaging. Pest risk maps, which are visual information to locate the appearance and destructiveness of potential invaders, are used to ease the uncertainty in species spread and aid in decision making to instigate the removal of invaders.
      In some cases, “wait and see” method has backfired, for instance, tropical alga (Caulerpa taxifolia) in Monaco occupied a few square metres in 1984 and due to negligence it conquered several thousand hectares.
      However, with the improvement in technology and further investigations, I believe that eventually, scientists would be able to confidently predict which species have the potential to be destructive even before their arrival! There are studies on nonnative insects invading North America’s conifer trees, there was a certainty of greater than 90% to foretell which nonnative species could be potential invaders! You can find out more in this article – https://www.scientificamerican.com/article/can-we-identify-invasive-species-before-they-invade/

      references
      Sims, C. and Finnoff, D., 2013. Resource And Energy Economics. [online] Www-sciencedirect-com.libproxy1.nus.edu.sg. Available at: <https://www-sciencedirect-com.libproxy1.nus.edu.sg/science/article/pii/S0928765513000055> [Accessed 15 September 2020].

      USDA 2010, retrieved from https://www.fs.usda.gov/treesearch/pubs/35034