Y’all ever heard of locusts? Bet you have. Yes, we’re talking the numero uno, our pest magnifico, the ones famously featured in the Holy Bible as a force of famine, set upon an ancient Egyptian Pharoah as divine punishment for enslaving an entire ethnic group. Surely, the locust is the prime example of an agricultural pest, demonstrating the most dramatic, destructive pest behaviour that we know. This National Geographic webpage does a good job explaining their biology, behaviour, and significance.

 

 

Unfortunately for us, there’s been a particularly bad upsurge of desert locust activity lately, putting affected countries at huge risk of food insecurity issues, according to the Food and Agricultural Organisation of the United Nations (FAO) in their latest global response plan to the crisis (FAO, 2020). Increased rainfall, due in big part to cyclonic activity in 2018 and 2019, provided the conditions for desert locusts to thrive and spread from the Middle East to East Africa and Southwest Asia over the past 2 years (FAO, 2020). As I write this, desert locusts continue to wreak havoc (FAO, last accessed 19th September 2020).

 

Some countries, like Kenya, were caught off guard, having not experienced locust swarms in 70 years (Baskar, 2020), and have taken to spraying them down with chemical insecticides, despite potentially deleterious environmental impacts (Lacave, 2020). Meanwhile, with the aid of the FAO (Stokstad, 2020), Somalia has been using a biopesticide containing Metarhizium acridum spores to successfully control populations of locust nymphs (FAO, last accessed 19th September 2020). As the Metarhizium acridum fungus only affects locusts and their relatives (Stokstad, 2020), it is less likely to cause unintentional harm to the environment when compared to chemical insecticides.

 

The main drawback of the M. Acridum biopesticide is its low potency compared to chemical insecticides (Stokstad, 2020). It works best on young nymphs (Stokstad, 2020), while chemical insecticides can be used against flying swarms as well (Lacave, 2020). This means chemical insecticides may still be necessary to take out established adult swarms when it comes down to it.

 

And another thing. Other forms of insect pests will not be affected by the biopesticide due to its specificity. Countries may not find it appealing to keep stores of a niche insecticide just to kill locusts when there are chemical insecticides that a) are more effective (Stokstad, 2020) and b) can deal with insect pest outbreaks of other forms. Can’t really blame them, either.

 

 

 

 

 

Projected increases in overall rainfall and frequency of tropical cyclones due to global warming (Cheng, 2019) could lead to even larger locust population booms as the years go by (Cressman as cited by Agarwal & Jain, 2020). Ideally, susceptible countries should explore and plan out effective and eco-friendly solutions before the next wave arrives, and keep the usage of harmful conventional insecticides to a minimum, perhaps as an emergency option against mature swarms. Improvements to existing technology, like a more potent M. Acridum biopesticide, would definitely make that process easier. And I’m hoping organisations like the FAO will continue to support and fund such efforts as needed.

 

Soooooo yeah. Don’t enslave minorities (I’m looking at you, Pharoah) and stay safe, y’all.

 

 

 

References

1. National Geographic (n.d.). Locusts. Retrieved September 19, 2020, from https://www.nationalgeographic.com/animals/invertebrates/group/locusts/

2. Food and Agriculture Organisation of the United Nations. (2020). Desert Locust Upsurge Global Response Plan January–December 2020. http://www.fao.org/3/ca9249en/CA9249EN.pdf

3. Food and Agriculture Organisation of the United Nations. (n.d.). Desert Locust situation update 18 September 2020. Retrieved September 19, 2020, from http://www.fao.org/ag/locusts/en/info/info/index.html

4. Baskar, P. (2020, June 14). Locusts Are A Plague Of Biblical Scope In 2020. Why? And … What Are They Exactly? Retrieved September 20, 2020, from https://www.npr.org/sections/goatsandsoda/2020/06/14/876002404/locusts-are-a-plague-of-biblical-scope-in-2020-why-and-what-are-they-exactly

5. Lacave, C. (2020, February 21). Kenya opts for pesticides to contain locust infestations. Retrieved September 20, 2020, from https://www.theafricareport.com/23745/kenya-opts-for-pesticides-to-contain-locust-infestations/#:~:text=As the devastating locust invasion,possible risks to the environment

6. Stokstad, E. (2020, February 12). In Somalia, an unprecedented effort to kill massive locust swarms with biocontrol. Retrieved September 20, 2020, from https://www.sciencemag.org/news/2020/02/somalia-unprecedented-effort-kill-massive-locust-swarms-biocontrol

7. Ngumbi, E. N. (2020, February 19). Africa’s most notorious insects – the bugs that hit agriculture the hardest. Retrieved September 19, 2020, from https://theconversation.com/africas-most-notorious-insects-the-bugs-that-hit-agriculture-the-hardest-83107

8. Cheng, L., Abraham, J., Zhu, J., Trenberth, K. E., Fasullo, J., Boyer, T., . . . Mann, M. E. (2020). Record-Setting Ocean Warmth Continued in 2019. Advances in Atmospheric Sciences, 37(2), 137-142. doi:10.1007/s00376-020-9283-7

9. Agarwal, K., & Jain, S. (2020, May 27). Climate Change Brings the Worst Locust Attack in Decades to India. Retrieved September 19, 2020, from https://science.thewire.in/environment/locust-attack-india-jaipur-climate-change/

 

I’ve been doing a bunch of reading up recently, and boy, things are going swimmingly. And by that I mean we’ll all be swimming by the end of the century. Jokes aside, things have been going downhill for a while now, or I suppose uphill along the temperature graph. As we all know, global temperatures are rising (NASA, 2020). And since this is a blog about pests, we shall focus specifically on how rising temperatures affect them.

 

Turns out there’s a general trend, but it’s complicated.

 

Recent research reveals that rice, maize, and wheat crops could be under threat in the coming years as warming global temperatures favor insect pests (Deutsch et al, 2018). According to the study, the temperate zone will be especially vulnerable, while the excessively-warm lowland tropics will see insect populations decline. Which I guess would be a good thing for crop-growers in the lowland tropics, if they can stand being uncomfortable and sweaty all the time. Even so, we’ll be bringing in 10 to 25% less of the staple crops whenever the temperature rises by 1 degree (Deutsch et al., 2018).

 

One possible limitation of the above study would be in its use of a generalised model of insect metabolism in its projection, which may not capture the nuances of individual species’ responses to environmental changes. Lehmann et al. (2020) echo this sentiment. Although they agree with the general predictions of Deutsch et al. (2018) regarding increasing pest severity, Lehmann et al. (2020) demonstrates that there is great variability to many species’ responses to warming depending on location. Additionally, their findings suggest that mid-latitude areas may be warming past pests’ optimal temperatures, as opposed to lowland regions as in the findings of Deutsch et al. (2018).

 

Lehmann et al. (2020) also propose that rapid evolution of pest species could cause unpredictability in these models. It’s unavoidable, but a challenge nonetheless.

 

 

So, clearly it’s not that simple, and there are some contradictory findings that need to be addressed. But either way, the evidence suggests that pest populations may grow in many parts of the world in the near future. Deutsch et al. (2018) postulates that pest population booms in intensive agriculture could lead to increasing pesticide use in order to protect crop yields. As a consequence, there would be an increased risk to environmental and human health, and of pesticide resistance (Deutsch et al., 2018). This would be a good segue to issues on pesticide use, but we’ll cover that in later posts.

 

 

Soooooo yeah. Keep it chill and stay safe, y’all.

 

 

References

1. NASA. (2020, July 16). Global Surface Temperature. Retrieved from https://climate.nasa.gov/vital-signs/global-temperature/

2. Deutsch, C. A., Tewksbury, J. J., Tigchelaar, M., Battisti, D. S., Merrill, S. C., Huey, R. B., & Naylor, R. L. (2018). Increase in crop losses to insect pests in a warming climate. Science, 361(6405), 916-919. doi:10.1126/science.aat3466

3. Lehmann, P. D., Ammunét, T. U., Barton, M. S., Battisti, A. U., Eigenbrode, S. U., Jepsen, J. U., . . . Björkman, C. U. (2020). Complex responses of global insect pests to climate warming. Frontiers in Ecology and the Environment, 18(3), 141-150. doi:10.1002/fee.2160

 

Images

Image of a cabbage whitefly by Amada44 / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0). Retrieved from https://commons.wikimedia.org/wiki/File:Cabbage_Whitefly_-_Aleyrodes_proletella_8618.jpg

Hi everyone, Isaac here. I’m currently studying in the National University of Singapore, as a 1st-year Bachelor of Environmental Studies Major. Now that I’ve introduced myself, let’s talk about this blog.

 

I’d never have thought that I’d have to write my own blog as part of a university module, but here we are. It’s fascinating to me that this is a gradable component, and I’m looking forward to it. To me, this blog is more than just a requirement to pass, but an impetus to look into environmental issues more critically then ever, and my first-ever foray into science communication.

 

In the subsequent weeks, I’ll be writing about pests and pesticides. Perhaps you could guess from my very witty blog title. Admittedly, my interest in world affairs have waxed and waned over the years, so I can’t say my current knowledge of pesticide use is… well, current. Or accurate. But hey! I didn’t come here claiming to know everything and I’m certainly very eager to fix my ignorance! That should count for something. And I’m sincerely hoping that the things I learn over the next few months could help you, too.

 

 

Also, I get to geek out over bugs. Look at this little thing. Dis round boi. It’s a devastator of potato crops and humanity wants it dead, but I still think it’s a fascinating and cute little creature. Of course, we aren’t just gonna look at insect pests, but prepare to see a lot more of them.

 

Soooooo yeah. Stay tuned for next week’s post, and stay safe, y’all.