Following the record temperatures and devastating regional flooding of 2019, a desert locust infestation unlike anything that has been seen in seventy years has descended on Kenya. Massive swarms of billions of locusts are currently threatening to wipe out huge swaths of agriculture in the country, as well as in nearby Ethiopia and Somalia, both which are experiencing their biggest infestations of the last 25 years.
In the worst case scenario the swarms will converge into a plague. If that happens they can easily affect over 20 percent of Earth’s land area. 10 percent of the world’s population would have their livelihood endangered as insects descend on 65 of the world’s poorest countries.
One of the swarms in Kenya encompasses approximately 2400 square kilometers, making it more than twice the size of Paris. It contains an estimated 96 billion locusts, each eating their own weight in food every day. If the swarms are not dealt with, they are expected to continue moving into neighbouring countries continuing to wreak untold devastation in their wake. In fact, Uganda had their first sightings of insects on February 2nd. Unless they are stopped the rapid-breeding locusts are expected to multiply by 500 times come June.
Somalian officials have declared a national emergency as a response to these events and all of the affected countries are trying to mobilize resources to deal with the problem. There is however a critical lack of funds and equipment as Kenya only has five operational pesticide spraying planes to combat the swarms, while Ethiopia sports a meagre three. Somalia meanwhile is crippled by internal conflicts, making many areas too insecure to reach.
Affected areas and current flight paths, 17 Feb 2020 // Created by Daniel Bergdal // Map from Mapswire and data from FAO
To effectively combat the swarm and put it under control before it proliferates further, the United Nations has declared that funds of $76 million are needed to improve spraying capacity. Seeing as the last upticks of swarms in West Africa 2003-2005 destroyed harvests worth $2.5 billion this option would be a relatively cheap solution. If not dealt with, the population would be in dire need of imported food which would amount to much steeper costs.
Further emphasizing the dangers locusts pose for local vegetation and agriculture, one could point to the 1954 Locust Swarms of northern Ethiopia which consumed 100 percent of the regions green-leaf plant cover. This plague, along with that year’s drought, lead to a yearlong famine.
Aerial spraying has been the only method that has so far proven effective, but it is far from unproblematic. The chemicals used are organophosphates which, unfortunately, also cause major damage to other insect populations vital to the ecosystem. One such example being bees, the pollinators of 70 percent of our food. The pesticides, while not directly deadly, also pose a risk to the health of humans and other animals in the region.
Much research has been done on developing alternative means of combating the swarms, such as insect growth regulators and directed pathogens, but it has so far not yielded the desired results.
Adult Desert Locust // Wikimedia Commons
Attempts at control by use of natural predators and parasites has also been unsuccessful due to the locusts’ natural ability at escaping areas containing natural enemies. The fact that many locusts are eaten by birds as well as humans is also nowhere near enough to significantly reduce population sizes.
Luckily enough the aerial spraying, while being the only effective method, has indeed proven to be very successful in the task of extermination. The major issue, as previously stated, being mostly logistical for the affected countries. Another issue however lies in the fact that spraying can only be done in the morning, when the coldblooded locusts have too little energy to take flight and must stay on the ground to heat up. Thus, if the weather in the morning is unsuitable for flying aircrafts, it is impossible to perform sprayings later during the day as the massive swarms spread over vast kilometres. The swarms can also fly so thick that they force aircraft down to land by clotting up engines and splattering across the windows, preventing vision for pilots.
So why is this happening right now? Where did all these locusts come from and how could they appear so suddenly and in such quantities? The answer to this lies in their biology. The desert locusts are actually a type of grasshopper which under normal circumstances live a solitary lifestyle without causing much trouble to humans at all. It is when they get overcrowded in areas of sparse vegetation that they become gregarious animals undergoing morphological transformations that change not only their behaviour but also their very appearance. They form mass swarms of billions where the now highly social animals communicate through pheromones and move together as one great unit.
Combined pictures of the desert locust in it’s solitary grasshopper stage (top) and it’s gregarious swarming state (bottom), both young with undeveloped wings // Pixabay and Pixabay
The reason why they have gotten so numerous is partly due to hotter global temperatures as well as the weather events of the Indian Ocean dipole. The last five years, as well as 2009, have been the hottest since the industrial revolution, and hot weather is ideal for locust growth. Africa is also disproportionately affected by the increasing temperatures, with 20 of the fastest warming countries in the world all situated on the continent.
The Indian Ocean dipole’s el niño-like weather events usually occur every ten years but with rising temperatures this has become more frequent and the storms have gotten more intense. Following intense ocean heats, East Africa was hit by eight cyclones in 2019 and the horn of Africa experienced rainfalls 400 percent above its usual average. Just as locusts like it warm, they also like it wet, and thus was created the perfect conditions for them to form the mega swarms that we see today.
Desert Locusts Mating // Wikimedia Commons
The locust infestation has caused widespread panic and desperation as farmers have been seen shooting in the air and banging cans together to scare the insects with the noise, as well as starting fires to keep them away. At a press conference in Nairobi an expert had to try and convince attendees that the events was not a biblical omen for the coming “end of times”.
Fortunately, enough most of this season’s harvests have already been performed, somewhat diminishing the swarms’ impact. Herders have however been dealt a heavier blow as the vegetation that their animals feed on are being consumed en masse. If the swarms are not defeated before March’s rain and planting season, farmers will likewise have their crops ravaged. This will be utterly devastating for a region where 19 million people already live with severe food insecurity.
Daniel Bergdal
