Rise in Insect Pests Under Climate Change to Hit Crop Yields, Study Says
By Daisy Dunne
Global warming could increase both the number and appetite of insect pests, new research finds, which could pose a serious threat to global crop production.
The study finds that global warming of 2C above pre-industrial levels—which is the limit set by the Paris agreement—could cause pest-related yield losses from wheat, rice and maize to increase by 46 percent, 19 percent and 31 percent, respectively.
And each additional degree of temperature rise could cause yield losses from insect pests to increase by a further 10-25 percent, the research shows.
Losses from pest infestation are likely to be largest in China, the U.S. and France—three of the world's most important grain producers, according to the findings.
At present, around 10-16 percent of global crop production is lost to pests—including insects, fungi and bacteria.
Thousands of insect species are known to threaten food production. One of the most well-known pests, the desert locust, feeds on a wide range of crops—including rice, maize and sugarcane—and can swarm and strip a crop field within an hour.
Other insects, such as the western corn rootworm, target specific crops. The rootworm, for example, feeds on maize during both its larval and adult beetle life stages and currently costs U.S. farmers around $1bn a year in lost revenue.
The new study, published in Science, explores how climate change could alter the activity of 38 of the world's most-studied insect crop pests.
First, rising temperatures boost the rate at which insects can digest food—causing them to demolish crops at a faster rate.
Second, in temperate regions, warming temperatures could cause insects—which are ectothermic or "cold-blooded"—to become more active and, thus, more able to reproduce.
For the study, the researchers made of use of existing data on how temperature is known to affect the population growth rate, food consumption rate and overall survival of insect pests under laboratory conditions.
The researchers used this information to inform a set of models projecting yield losses from insect pests for wheat, rice and maize under different levels of temperature rise. The projections assumed that total global crop yields will remain the same as today.
The charts below show the expected crop yield loss in megatonnes per year as a result of increased insect food consumption—or "metabolic activity"—(purple triangles) and population growth (orange circles and green asterisks) for wheat (A), rice (B) and maize (C) under various levels of global temperature rise. A dashed line is used to indicate the current loss as a result of insect pests.
[Chart above] — Projected crop yield losses (megatonnes per year) as a result of increased insect metabolic activity (purple triangles) and two estimations of population growth using different demographic parameters (orange circles and green asterisks) for wheat (A), rice (B) and maize (C) under temperature rise of 1-5C above pre-industrial levels. A dashed line shows the current amount of crop losses from insect pests. Source: Deutsch et al. (2018)
The results show that, under 2C of global warming, pest-related yield losses from wheat, rice and maize increase by 46 percent, 19 percent and 31 percent, respectively, when compared to current levels of loss. Each additional degree of temperature rise could cause global yield losses from insect pests to increase by a further 10-25 percent, the results suggest.
Losses are projected to be largest for maize and wheat because these crops are mostly grown in temperate regions – where warming is expected to boost insect population numbers, the researchers say.
Rice, on the other hand, is grown mostly in tropical regions—where temperatures are already optimal for insect reproduction. Further temperature increases are therefore likely to cause small declines in insect numbers, the research finds, leading to an overall smaller effect on yield losses.
The maps below show the projected geographic pattern of insect-related yield losses for wheat (A), rice (B) and maize (C) under 2C of global warming. On the maps, dark red shows large percentage increases in crop losses while dark blue shows large decreases.
[Map above] — The projected distribution of insect-related yield losses for wheat (A), rice (B) and maize (C) under 2C of global warming. Dark red shows increased losses, while dark blue shows decreased losses. Source: Deutsch et al. (2018)
The maps show how the largest losses to crop yields in percentage terms are expected in Europe and North America, including in the U.S. and France—two of the world's largest grain producers.
Europe's wheat-growing regions—collectively the most productive in the world—could be particularly affected by losses, the results show. Up to 11 European countries, including the UK, Sweden and Ireland, could face insect-related losses of 75 percent or higher, the study finds.
Moderate losses are also projected across much of sub-Saharan Africa and southeast Asia—two regions currently facing high levels of hunger. Writing in their research paper, the authors said:
"Poor grain consumers and farming households, who account for a large share of the world's 800 million people living in chronic hunger, will suffer most."
Knowing the Enemy
The findings should serve a "call for action on climate change mitigation and adaptation," Prof. Markus Riegler, an insect biologist from Western Sydney University, writes in an accompanying perspectives article. He said:
"Everyone must be involved in change: farmers, industries, policymakers, and the wider society. There is also an increased need to focus on plant protection, particularly given that many insecticides are being banned over human and environmental health concerns."
The research offers "a global perspective" of how climate change could impact the damages caused by pests, said Prof. Christer Björkman, an insect ecologist from the Swedish University of Agricultural Sciences, who was not involved in the study. However, the study does have a few shortcomings, he told Carbon Brief:
"One is that the authors only model the pests themselves. This is a great simplification because we know their host plants and their natural enemies are affected by the same temperature changes."
"In other words, the study ignores many key ecological interactions of potentially great importance. Another [unconsidered factor is] the nutritional value of plants may change."
Research covered by Carbon Brief earlier this week found that the nutritional value of key crops including rice, wheat and maize is likely to fall as CO2 levels rise.
If crops become less nutritious, insects will have to consume more plant matter to get the nutrients they need, Björkman said, potentially raising yield losses further.
Reposted with permission from our media associate Carbon Brief.
Fifteen states are in for an unusually noisy spring.
- Millions of Cicadas Set to Emerge After 17 Years Underground ... ›
- Cicadas Show Up 4 Years Early - EcoWatch ›
EcoWatch Daily Newsletter
Deep in the woods, a hairy, ape-like man is said to be living a quiet and secluded life. While some deny the creature's existence, others spend their lives trying to prove it.
- Why Hunting Isn't Conservation, and Why It Matters - Rewilding ›
- Decline In Hunters Threatens How U.S. Pays For Conservation : NPR ›
- Is Hunting Conservation? Let's examine it closely ›
- Oklahoma Department of Wildlife Conservation | Oklahoma ... ›
- Oklahoma Bill Calls for Bigfoot Hunting Season | Is Bigfoot Real? ›
By Jon Queally
Noted author and 350.org co-founder Bill McKibben was among the first to celebrate word that the president of the European Investment Bank on Wednesday openly declared, "To put it mildly, gas is over" — an admission that squares with what climate experts and economists have been saying for years if not decades.
- Fossil Fuel Industry Is Now 'in the Death Knell Phase': CNBC's Jim ... ›
- Mayors of 12 Major Global Cities Pledge Fossil Fuel Divestment ... ›
- World's Largest Public Bank Ditches Oil and Coal in Victory for the ... ›
Nine feet tall is gigantic by human standards, but when researcher and conservationist Michael Brown spotted a giraffe in Uganda's Murchison Falls National Park that measured nine feet, four inches, he was shocked.
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="54af350ee3a2950e0e5e69d926a55d83"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/yf4NRKzzTFk?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
- Giraffe Parts Sold Across U.S. Despite Plummeting Wild Populations ... ›
- Green Groups Sue to Get Giraffes on Endangered Species List ... ›
- Conservationists Sound Alarm on Plummeting Giraffe Numbers ... ›
By Daisy Simmons
1. Stay Informed<p>A first order of business in pet evacuation planning is to understand and be ready for the possible threats in your area. Visit <a href="https://www.ready.gov/be-informed" target="_blank">Ready.gov</a> to learn more about preparing for potential disasters such as floods, hurricanes, and wildfires. Then pay attention to related updates by tuning <a href="http://www.weather.gov/nwr/" target="_blank">NOAA Weather Radio</a> to your local emergency station or using the <a href="https://www.fema.gov/mobile-app" target="_blank">FEMA app</a> to get National Weather Service alerts.</p>
2. Ensure Your Pet is Easily Identifiable<p><span>Household pets, including indoor cats, should wear collars with ID tags that have your mobile phone number. </span><a href="https://www.avma.org/microchipping-animals-faq" target="_blank" rel="noopener noreferrer">Microchipping</a><span> your pets will also improve your chances of reunion should you become separated. Be sure to add an emergency contact for friends or relatives outside your immediate area.</span></p><p>Additionally, use <a href="https://secure.aspca.org/take-action/order-your-pet-safety-pack" target="_blank" rel="noopener noreferrer">'animals inside' door/window stickers</a> to show rescue workers how many pets live there. (If you evacuate with your pets, quickly write "Evacuated" on the sticker so first responders don't waste time searching for them.)</p>
3. Make a Pet Evacuation Plan<p> "No family disaster plan is complete without including your pets and all of your animals," says veterinarian Heather Case in <a href="https://www.youtube.com/watch?v=Q9NRJkFKAm4" target="_blank">a video</a> produced by the American Veterinary Medical Association.</p><p>It's important to determine where to take your pet in the event of an emergency.</p><p>Red Cross shelters and many other emergency shelters allow only service animals. Ask your vet, local animal shelters, and emergency management officials for information on local and regional animal sheltering options.</p><p>For those with access to the rare shelter that allows pets, CDC offers <a href="https://www.cdc.gov/healthypets/emergencies/pets-in-evacuation-centers.html" target="_blank">tips on what to expect</a> there, including potential health risks and hygiene best practices.</p><p>Beyond that, talk with family or friends outside the evacuation area about potentially hosting you and/or your pet if you're comfortable doing so. Search for pet-friendly hotel or boarding options along key evacuation routes.</p><p>If you have exotic pets or a mix of large and small animals, you may need to identify multiple locations to shelter them.</p><p>For other household pets like hamsters, snakes, and fish, the SPCA recommends that if they normally live in a cage, they should be transported in that cage. If the enclosure is too big to transport, however, transfer them to a smaller container temporarily. (More on that <a href="https://www.spcai.org/take-action/emergency-preparedness/evacuation-how-to-be-pet-prepared" target="_blank" rel="noopener noreferrer">here</a>.)</p><p>For any pet, a key step is to establish who in your household will be the point person for gathering up pets and bringing their supplies. Keep in mind that you may not be home when disaster strikes, so come up with a Plan B. For example, you might form a buddy system with neighbors with pets, or coordinate with a trusted pet sitter.</p>
4. Prepare a Pet Evacuation Kit<p>Like the emergency preparedness kit you'd prepare for humans, assemble basic survival items for your pets in a sturdy, easy-to-grab container. Items should include:</p><ul><li>Water, food, and medicine to last a week or two;</li><li>Water, food bowls, and a can opener if packing wet food;</li><li>Litter supplies for cats (a shoebox lined with a plastic bag and litter may work);</li><li>Leashes, harnesses, or vehicle restraints if applicable;</li><li>A <a href="https://www.avma.org/resources/pet-owners/emergencycare/pet-first-aid-supplies-checklist" target="_blank">pet first aid kit</a>;</li><li>A sturdy carrier or crate for each cat or dog. In addition to easing transport, these may serve as your pet's most familiar or safe space in an unfamiliar environment;</li><li>A favorite toy and/or blanket;</li><li>If your pet is prone to anxiety or stress, the American Kennel Club suggests adding <a href="https://www.akc.org/expert-advice/home-living/create-emergency-evacuation-plan-dog/" target="_blank" rel="noopener noreferrer">stress-relieving items</a> like an anxiety vest or calming sprays.</li></ul><p>In the not-unlikely event that you and your pet have to shelter in different places, your kit should also include:</p><ul><li>Detailed information including contact information for you, your vet, and other emergency contacts;</li><li>A list with phone numbers and addresses of potential destinations, including pet-friendly hotels and emergency boarding facilities near your planned evacuation routes, plus friends or relatives in other areas who might be willing to host you or your pet;</li><li>Medical information including vaccine records and a current rabies vaccination tag;</li><li>Feeding notes including portions and sizes in case you need to leave your pet in someone else's care;</li><li>A photo of you and your pet for identification purposes.</li></ul>
5. Be Ready to Evacuate at Any Time<p>It's always wise to be prepared, but stay especially vigilant in high-risk periods during fire or hurricane season. Practice evacuating at different times of day. Make sure your grab-and-go kit is up to date and in a convenient location, and keep leashes and carriers by the exit door. You might even stow a thick pillowcase under your bed for middle-of-the-night, dash-out emergencies when you don't have time to coax an anxious pet into a carrier. If forecasters warn of potential wildfire, a hurricane, or other dangerous conditions, bring outdoor pets inside so you can keep a close eye on them.</p><p>As with any emergency, the key is to be prepared. As the American Kennel Club points out, "If you panic, it will agitate your dog. Therefore, <a href="https://www.akc.org/expert-advice/home-living/create-emergency-evacuation-plan-dog/" target="_blank" rel="noopener noreferrer">pet disaster preparedness</a> will not only reduce your anxiety but will help reduce your pet's anxiety too."</p>
Evacuating Horses and Other Farm Animals<p>The same basic principles apply for evacuating horses and most other livestock. Provide each with some form of identification. Ensure that adequate food, water, and medicine are available. And develop a clear plan on where to go and how to get there.</p><p>Sheltering and transporting farm animals requires careful coordination, from identifying potential shelter space at fairgrounds, racetracks, or pastures, to ensuring enough space is available in vehicles and trailers – not to mention handlers and drivers on hand to support the effort.</p><p>For most farm animals, the Red Cross advises that you consider precautionary evacuation when a threat seems imminent but evacuation orders haven't yet been announced. The American Veterinary Medical Association has <a href="https://www.avma.org/resources/pet-owners/emergencycare/large-animals-and-livestock-disasters" target="_blank">more information</a>.</p>
Bottom Line: If You Need to Evacuate, So Do Your Pets<p>As the Humane Society warns, pets left behind in a disaster can easily be injured, lost, or killed. Plan ahead to make sure you can safely evacuate your entire household – furry members included.</p>
- 5 Ways to Be an Eco-Friendly Pet Owner - EcoWatch ›
- Can Your Pets Get and Transmit Coronavirus? - EcoWatch ›