09
Jan
Regulations to Protect Bees Fall Short, Scientists Call for More Attention to Native Bees
(Beyond Pesticides, January 9, 2019) It is news to approximately no one that pollinators are in trouble worldwide. A series of papers by biologists at the University of Guelph, Ontario, posits that pesticide regulations aimed at protection of honey bees fall far short of the critical task of protecting the multitude of bee species that are important pollinators of human food crops. These recent papers arose from 2017 workshops that involved 40 bee researchers from various universities, and representatives from Canadian, U.S., and European regulatory agencies, and from the agrochemical industry.
Beset by shrinking habitat, pathogens, and toxic chemical exposures, bee pollinator populations are at great risk, even as “‘our dependency on insect-pollinated crops is increasing and will continue to do so as the global population rises,’ said [Professor Nigel] Raine, [PhD], [a] co-author of all three papers recently published in the journal Environmental Entomology. . . . Protecting wild pollinators is more important now than ever before. Honeybees alone simply cannot deliver the crop pollination services we need.” There are, in fact, more than 20,000 bee species worldwide, and 3,500–5,000 bee species in North America alone.
Although regulators across many countries have focused narrowly on assessing the risk of pesticides to honey bees, many of which are “managed” for commercial pollination services, Dr. Raine notes that wild bee species — including bumblebees, mason bees, solitary bees, and others — are likely more important for food crop pollination than managed honeybees, such as those used extensively in the American West. A significant portion of those wild species live in soils as larvae and/or adults. Exposure of those species through pesticide residues in soil or food sources is essentially unstudied by researchers. The University of Guelph biologists, in their papers, call for regulators to expand their purview regarding pollinator risks, perhaps by using solitary bees and bumblebees as models.
The abstract for the papers’ publication says, “Current pesticide risk assessment practices use the honey bee, Apis mellifera L., as a surrogate to characterize the likelihood of chemical exposure of a candidate pesticide for all bee species. Bees make up a diverse insect group that provides critical pollination services to both managed and wild ecosystems. Accordingly, they display a diversity of behaviors and vary greatly in their lifestyles and phenologies, such as their timing of emergence, degree of sociality, and foraging and nesting behaviors. Some of these factors may lead to disparate or variable routes of exposure when compared to honey bees.” Pesticide exposures for wild bees can happen through their food (nectar and pollen), via airborne molecules (from spraying or volatilized through abrasion of seed coatings), in nesting substrates (especially in soils, for ground-dwelling species), in water sources, via contact with contaminated plant foliage, and even through contact with residues in the wax they produce to protect their offspring.
Angela Gradish, PhD, lead author on one of the papers and a research associate in the University of Guelph School of Environmental Sciences, adds to the argument, saying, “Everybody is focused on honeybees. . . . What about these other bees? There are a lot of unknowns about how bumblebees are exposed to pesticides in agricultural environments.” She notes, for example, that the bumblebee queen life cycle, which differs from that of the honeybee queen, may increase those queens’ exposures to pesticides while they collect food and establish their colonies. Dr. Gradish notes, “That’s a critical difference because the loss of a single bumblebee queen translates into the loss of the colony that she would have produced. It’s one queen, but it’s a whole colony at risk.” Further, other non-honeybee species may vary in body size, food consumption rates, nesting habitats and substrates, overwintering strategies, and foraging times and behaviors, among other features.
The “crash” of pollinators is happening in a wider context of biological and biodiversity loss. The lack of attention to loss in insect populations broadly was identified in a dramatic November 18, 2018 New York Times article, “The Insect Apocalypse Is Here,” which called out the staggering attrition in insect populations during the last few decades. Here in the U.S., scientists discovered relatively recently that the population of monarch butterflies has fallen by 90% in the last 20 years, and that populations of the rusty-patched bumblebee (which used to be found in 28 states) dropped by 87% in the same period. Beyond Pesticides also noted the phenomenon in its coverage of a 2017 study by a German entomological society, which found a decline in total flying insect biomass in protected areas of the country of more than 75% over a 27-year period.
The New York Times piece also quoted North Carolina State University ecologist Rob Dunn, PhD, who searched for studies on the effects of pesticide spraying on insect populations living in nearby forests, only to find there were none: “We [have] ignored really basic questions. . . . It feels like we’ve dropped the ball in some giant collective way.” The New York Times also reported a shocking reality: “A 2013 paper in [the journal] Nature, which modeled both natural and computer-generated food webs, suggested that a loss of even 30 percent of a species’ abundance can be so destabilizing that other species start going fully, numerically extinct — in fact, 80 percent of the time it was a secondarily affected creature that was the first to disappear.”
These recent papers contribute to a growing body of work that points to inadequacies in regulation of (and research on) toxic pesticides, as regards their impacts on pollinators and on the insect universe. Not only are individual pesticides poorly evaluated at the federal level (see examples here and here), but also, there is wholly insufficient attention paid to the systemic and synergistic effects of toxic pesticides on ecosystems and organisms of all sorts. Beyond Pesticides wrote extensively, in the Summer 2018 issue of its journal, Pesticides and You, about an example of such systemic impacts — the ripples, up and down a food chain, that can happen when even one species in an ecosystem is harmed. Such a disturbance in functional ecosystem balance is often called a “trophic cascade”: a series of indirect ecosystem effects set off by a change in the status or abundance of a predator or prey organism. As The New York Times wrote, “One result of [insect] loss is what’s known as [a] trophic cascade, the unraveling of an ecosystem’s fabric as prey populations boom and crash and the various levels of the food web no longer keep each other in check. These places are emptier, impoverished in a thousand subtle ways.”
At this juncture, the multitude of studies that demonstrate the huge variety and complexity of harmful impacts of pesticide exposures to pollinators makes identifying the “most important” impacts — and how to protect pollinators from them — not only a Sisyphian task, but perhaps a bit beside the point. The many studies on which Beyond Pesticides has reported in its Daily News Blog, and in its databases (see Pesticide Induced Database, Gateway on Pesticide Hazards and Safe Pest Management, Eating with a Conscience database, and the Manage Safe database), demonstrate that pesticide exposures have consequences that amount to broad and indiscriminate poisoning of, and trophic effects on, organisms and the environment. The University of Guelph’s Professor Raine commented, “‘I hope we can address shortfalls in the pesticide regulatory process. . . . Given the great variability that we see in the behaviour, ecology and life history of over 20,000 species of bees in the world, there are some routes of pesticide exposure that are not adequately considered in risk assessments focusing only on honeybees.’”
Beyond Pesticides advocates for a rapid transition to organic management practices as key to protecting pollinators and the environment. Regulatory agencies should adopt this goal and legally prohibit the use of toxic synthetic pesticides, thereby establishing a systems approach that would protect environmental and organismic — pollinator, human, and all other — health. See the Beyond Pesticides website pages on its BEE Protective program for more information on pollinator health and how to advocate for it.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: https://www.eurekalert.org/pub_releases/2018-12/uog-spr121118.php
FULLY protect our native bees!!! No half-measures!
January 14th, 2019 at 3:32 pm