- Author: Kathy Keatley Garvey
A monarch butterfly fluttered into our pollinator garden in Vacaville yesterday and sipped nectar from a Mexican sunflower (Tithonia) as a bird looked on.
Well, sort of looked on.
The bird was decorative art. The monarch was real.
Now if that bird had been real, the monarch may have been a meal.
It would not have tasted very good, though, due to the infamous cardenolide defense, which the monarch gets in its caterpillar stage while chowing down milkweed, its host plant.
Yes, birds eat monarch butterflies, but they don't eat them like people eat potato chips.
We remember the Linda Fink-Lincoln Brower research article published in May 1981 in the journal Nature about how some birds can overcome the cardenolide defense of monarch butterflies in Mexico.
The abstract:
"Flocks of black-backed orioles (Icterus abeillei Lesson) and black-headed grosbeaks (Pheucticus melanocephalus Swainson) eat several hundred thousand monarch butterflies (Danaus plexippus L.) in the dense overwintering colonies in central Mexico, and in 1979 were responsible for over 60% of the butterfly mortality at several sites. Such predation is unusual because, during larval development the aposematically coloured monarch butterfly sequesters cardenolides from its milkweed foodplants (Asclepiadaceae). These bitter-tasting heart poisons cause vomiting in 12 species of birds in 9 families, although the domestic chicken, Japanese quail, hedgehog, mouse and sheep have been shown to be insensitive to their emetic effects. Extensive predation of monarch butterflies by birds has never been observed except in Mexico. We report here that the Mexican butterflies are weakly emetic, and that taste discrimination by orioles and cardenolide insensitivity of grosbeaks allow these birds to feed freely on monarch butterflies."
We've seen birds scatter the overwintering monarchs roosting in the eucalyptus trees at Pacific Grove, Santa Cruz, but never witnessed an all-you-can-eat buffet. They ate a few, though.
- Author: Kathy Keatley Garvey
That includes pollinator habitat.
In their paper, “Techno-Ecological Synergies of Solar Energy for Global Sustainability,” published today (July 9), the researchers propose a “techno–ecological synergy (TES), a framework for engineering mutually beneficial relationships between technological and ecological systems, as an approach to augment the sustainability of solar energy across a diverse suite of recipient environments, including land, food, water, and built-up systems.”
They provided “a conceptual model and framework to describe 16 TES of solar energy and characterize 20 potential techno–ecological synergistic outcomes of their use.”
The paper offers what is considered the most complete list yet of the advantages of solar energy. "The study also marks the launch of a partnership between the Center for Biological Diversity and UC Davis to advance a Wild Energy future, which emphasizes the potential of solar energy systems to benefit not only humans, but the entire planet," according to a UC Davis news release.
Despite solar energy's growing penetration in the global marketplace, “rarely discussed is an expansion of solar energy engineering principles beyond process and enterprise to account for both economic and ecological systems, including ecosystem goods and services,” wrote lead author Rebecca Hernandez of the UC Davis Department of Land, Air and Water Resources and the Wild Energy Initiative of the John Muir Institute of the Environment, UC Davis. She considers the first step in creating a wild-energy future is "understanding the true value of solar."
The researchers defined TES “as a systems-based approach to sustainable development emphasizing synergistic outcomes across technological and ecological boundaries…solar energy combined with TES may prove a promising solution for avoiding unintended consequences of a rapid renewable energy transition on nature by mitigating global change-type problems.”
Co-author and entomologist Leslie Saul-Gershenz, associate director of research for the Wild Energy Initiative, John Muir Institute of the Environment, said it is imperative to protect our ecological system, which includes pollinators and their required resources. Among them: nest sites, and pollen and nectar resources.
“Native pollinators face global pressure from many sources of habitat alteration, pesticide use, invasive non-native plants, and climate change,” said Saul-Gershenz, who received her doctorate in entomology from UC Davis. “We are proposing land sparing priorities in undisturbed ecosystems, such as arid lands in the Mojave and Sonoran deserts, which sustain some of the highest native pollinator species diversity in the United States. We add the valuation of these pollinators as essential resources into the calculation when selecting sites to deliver renewable energy goals to achieve true tech-ecological synergy and global sustainability.”
Solar cells, called photovoltaic (PV) solar energy, convert sunlight directly into electricity. For example, in Minnesota and Vermont, land adjacent to croplands is developed with PV solar energy, the authors noted. The low-growing flowering plants for native and managed pollinators help increase agricultural yields, reduce management (that is, mowing) costs, and confer the opportunity to produce honey and other honey-based commodities.
The researchers concluded that “achieving a rapid transition from fossil fuels to renewable energy sources on planet Earth to support human activities, in a manner benign to Earth's life support systems, is arguably the grandest challenge facing civilization today. The consequences of climate and other types of global environmental change are a cautionary flag against the extrapolation of past energy decisions.”
Hernandez initiated the research and led the conceptual design and writing of the manuscript All authors contributed to further content development and drafting of the manuscript. The team also included researchers from UC Berkeley, UC Riverside and UC San Diego, as well as scientists from Lancaster University in the United Kingdom; U.S. Fish and Wildlife Services, Sacramento; Center for Biological Services, Tucson, Ariz.; Université de Thiès, Senegal; Centers for Pollinators in Energy, Fresh Energy, St. Paul, Minn.; National Renewable Energy Laboratory, Golden, Co.; and Renewable Energy and Environmental Finance Group, Wells Fargo, San Francisco.
Look for more research on solar energy!
"Solar energy is the fastest-growing source of power worldwide," according to the UC Davis news release. "In 2019, solar is expected to provide more than 30 percent of all new U.S. electric capacity. According to the International Energy Agency, solar energy could become the largest electricity source by 2050. Solar has many advantages beyond providing power, particularly when built to maximize social, technological and environmental benefits."
- Author: Kathy Keatley Garvey
The brown planthopper, Nilaparvata lugens, or BPH, is the economically most important rice pest in Asia. It's found only in southeast Asia and Australia, but the methods that a nine-member research team used may be appropriate here in the rice-growing areas of California, says UC Davis agricultural entomologist Christian Nansen, who was part of a nine-member team that just published first-of-its-kind research. It appears in Scientific Reports of the journal Nature.
Using the sustainable pest management method known as "the banker plant system," they did field and laboratory work in China with good results: attracting alternative hosts to parasitoids of rice insect pests, can help protect a rice crop. The players: a grass species, a planthopper, and an egg parasitoid.
Research results showed that BPH densities were significantly lower in the rice fields with the sustainable pest management practice known as the banker plant system compared to control rice fields without the banker plant system, the scientists said.
“Many people are familiar with the concept of a ‘trap crop'-- a sacrificial crop which is planted mixed in with or adjacent to an economically important crop and the trap crop serves to manipulate pests away by offering them a more attractive/suitable host alternative,” said Nansen, an assistant professor with the UC Davis Department of Entomology and Nematology. “The use of banker plants in pest management is similar to the use of trap crops, but banker plants typically have multiple ecological functions.”
The researchers planted a grass species, Leersia sayanuka, next to rice. It attracted a planthopper (Nilaparvata muiri), which does not infest rice.
Rice is the stable food of more than 50 percent of the global population, and 60 percent of the Chinese population. However, scientists concur that the world's rice production needs to increase drastically over the next three decades to meet the growing food demand in Asia. Growing concern over BPH outbreaks and higher pesticide usage led to the sustainable pest management study.
Titled “Use of Banker Plant System for Sustainable Management of the Most Important Insect Pest in Rice Fields in China,” the research is unique in that it is the first published study describing the attraction of alternative hosts to parasitoids of rice insect pests. In rice systems, previously published research involved planting sesame as a nectar source to promote the establishment and persistence of a predatory bug; and studies involving parasitoids.
BPH feeds on the rice crop at all stages of plant growth and can also transmit two viruses, rice ragged stunt virus, and rice grassy stunt virus. Damage can commonly result in a 60 percent yield loss. An infestation is often called “hopper burn,” referring to yellow patches that soon turn brown.
Noting the importance of the banker plant system, Nansen said that banker plants “involve promotion of plant diversity to enhance pest self-regulatory ecosystem functions, such as predation and competition, to reduce susceptibility of agricultural crops to native and invasive pests. Also, banker plants “may provide resources, such as shelter, pollen and nectar or alternative preys to improve the establishment and persistence of beneficial insect populations used to control a specific pest.” The first successful banker plant system, developed in 1977, involved tomato as the banker plant, a parasitoid and a whitefly.
Nansen is affiliated with both UC Davis and the Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
Co-authors of the research paper include lead author Zhongxian Lu and colleagues Xusong Zheng, Yanhui Lu, Junce Tian, Hongxing Xu, all of the Zhejiang Sustainable Pest and Disease Control; and Pingyang Zhu, Facheng Zhang and Guihua Chen of the Jinhua (China) Plant Protection Station.
The study was jointly supported by the National Key Research and Development Program of China, Zhejiang Key Research and Development Program, and the Special Fund for Agro-scientific Research in the Public Interest.
- Author: Kathy Keatley Garvey
When the United Nations meets Sept. 21 in New York, they want the UN to reframe its action on the global antimicrobial drug resistance (AMR) crisis.
It's crucial. How crucial is it?
Antimicrobial drug resistance threatens both personal and planetary health and the issue is as crucial as the global threat of climate change, Carroll says.
In a paper titled “Use Antimicrobials Wisely,” published in the current edition of Nature, a nine-member international research team, including Carroll, explained their advocacy.
“We're concerned about what will happen if the proposed UN solutions focus mainly on incentives for new drug development, at a time when the drug industry itself is abandoning those efforts against infectious disease due to AMR,” said Carroll, who co-leads the international group on resistance to pesticides and antimicrobial drugs. He founded and directs the Institute for Contemporary Evolution, Davis, and is affiliated with the Sharon Lawler lab, UC Davis Department of Entomology and Nematology.
The paper, published in the Comment section, is the first product from a two-year working group sponsored by the National Socio-Environmental Synthesis Center in Annapolis, Md. “We are taking a similar socio-environmental approach in our concurrent work on pesticide stewardship,” Carroll said.
“While new drugs have a role, we think it's more important for society to learn how to steward pathogen susceptibility, so we develop that theme in the paper,” Carroll said. “And because we also depend on microbes for digestion, immunity, and general health, and microbes support ecosystem functioning through nutrient cycles and the maintenance of soil and water quality, we further argue that our AM drug habits and waste streams threaten both personal and planetary health. “
Lead authors of the paper are Peter Jorgensen of Stockholm, Sweden, and Didier Wernli of Geneva Switzerland. Jørgensen, who spent part of his Danish graduate program working with Carroll in Davis, is now a postdoctoral researcher at the Royal Swedish Academy of Science, Stockholm.
Carroll described AMR as more than a medical dilemma—it's a socio-ecological problem. “The vulnerability of pathogens to antimicrobial drugs is a communal resource, readily threatened by overuse, to be lost as a classic 'tragedy of the commons.' There is a lot of contemporary theory for social resilience in the face of socio-ecological challenges, and– linking to entomology– the early success of the pioneering management of Bt crop pest resistance evolution is an encouraging precedent.”
In its planetary health approach, the group seeks to be “more cognizant not only of preserving drug susceptibility in pathogenic microbes, but also protecting from wholesale destruction the community of microbes on which we depend for life,” Carroll said.
In the paper, the scientists pointed out that “Resistance affects animal and environmental health as well as human health, and so requires coordinated action across economic sectors. No single concern exemplifies this better than the high rate of antibiotic use in agriculture (largely as growth promoters or disease prevention).” They wrote that in the United States, 70 to 80 percent of all anti-microbials consumed are given to livestock.
An example of antimicrobial resistance involves the malaria mosquito, Anopheles gambiae. The World Health Organization (WHO) in a document, "Global Action Plan on Anti-Microbial Resistance," wrote:
"Antimicrobial resistance can affect all patients and families. Some of the commonest childhood diseases in developing countries – malaria, pneumonia, other respiratory infections, and dysentery – can no longer be cured with many older antibiotics or medicines. In lower- income countries, effective and accessible antibiotics are crucial for saving the lives of children who have those diseases, as well as other conditions such as bacterial blood infections. In all countries, some routine surgical operations and cancer chemotherapy will become less safe without effective antibiotics to protect against infections."
Expect to hear more about this alarming crisis--the global antimicrobial drug resistance crisis. Meanwhile, read the WHO Global Action Plan.
- Author: Kathy Keatley Garvey
The mosquito-borne viral disease known as “breakbone fever,” is three times more prevalent than originally thought, according to a research paper published today in Nature and co-authored by dengue expert Thomas Scott of UC Davis.
In their research paper, titled “The Global Distribution and Burden of Dengue,” Scott and the 17 other team members estimated that 350 million people are infected each year--more than triple the World Health Organization’s current estimate of 50 to 100 million.
Professor Simon Hay of the University of Oxford led the research as part of the International Research Consortium on Dengue Risk Assessment, Management and Surveillance.
“Dengue takes an enormous toll on human health worldwide, with as many as 4 billion people at risk," said Scott, a UC Davis professor of entomology and worldwide expert on the epidemiology and prevention of dengue. He chairs the mosquito-borne disease modelling group in the Research and Policy for Infectious Disease Dynamics (RAPIDD) program of the Science and Technology Directory, Department of Homeland Security, Fogarty International Center, National Institutes of Health.
“The results of our study and infrastructure that created the dengue maps fill a critical gap in the battle against dengue,” said Scott, who maintains field research programs in Iquitos, Peru, and Khamphaeng Phet, Thailand. “Prior to this, without rigorously derived dengue estimates that can be continuously updated, it was not possible to know with confidence where and when to direct interventions for greatest potential impact or to objectively assess the effectiveness of regional and global control efforts. That kind of knowledge was among the most important missing information for developing enhanced dengue prevention programs.”
The highly infectious tropical and subtropical disease is spread by the bite of an infected female Aedes aegypti, a day-biting, limited flight-range mosquito that prefers human blood to develop its eggs. Dengue is caused by four distinct, but closely related, viruses. The most severe form of disease is life-threatening dengue hemorrhagic fever or DHF.
The researchers assembled known records of dengue occurrence worldwide and used a formal modelling framework to map the global distribution of dengue risk. They then paired the resulting risk map with detailed longitudinal information from dengue cohort studies and population surfaces to infer the public health burden of dengue in 2010.
“There are currently no licensed vaccines or specific therapeutics, and substantial vector control efforts have not stopped its rapid emergence and global spread,” the researchers wrote.
Dengue has now begun to appear along the southern border of the United States, including Texas. Florida has also reported cases of dengue.
Of the 96 million clinically apparent dengue infections, Asia bears 70 percent of the burden, the research paper revealed. India alone accounts for around one-third of all infections.