09
Apr
Neonicotinoids Adversely Affect Biodiversity, According to New Report
(Beyond Pesticides, April 9, 2015) — A new report released yesterday by the European Academies Science Advisory Council on neonicotinoid insecticides finds that “[T]here is more and more evidence that widespread use of neonicotinoids has severe effects on a range of organisms that provide ecosystem services like pollination and natural pest control, as well as on biodiversity.” The report points to major declines of wild bee species, other pollinators, insect species with natural pest control functions and biodiversity indicators such as farmland birds. The report, Ecosystem Services, agriculture and neonicotinoids, finds the following:
1. There is an increasing body of evidence that the widespread prophylactic use of neonicotinoids has severe negative effects on non-target organisms that provide ecosystem services including pollination and natural pest control.
2. There is clear scientific evidence for sublethal effects of very low levels of neonicotinoids over extended periods on non-target beneficial organisms. These should be addressed in EU approval procedures.
3. Current practice of prophylactic usage of neonicotinoids is inconsistent with the basic principles of integrated pest management as expressed in the EU’s Sustainable Pesticides Directive.
4. Widespread use of neonicotinoids (as well as other pesticides) constrains the potential for restoring biodiversity in farmland under the EU’s Agri-environment Regulation.
Regarding the economic effect of natural pollination services, the report says,
The value of pollination services to agriculture is relatively straightforward to quantify compared with other ecosystem services; a study by Gallai et al. (2009) assessed the contribution of insect pollination to agricultural output worldwide, and concluded that the total annual economic value of pollination services amounts to approximately €153 billion. Recent studies on economic gains attributed to insect (particularly honey bee) pollination suggest that, across Europe, crop pollination by insects accounted for €14.6 billion ( ±â‚¬3.3 billion) annually, which equalled 12% ( ±0.8%) of the total economic value of annual crop production (Leonhardt et al., 2013).
In the USA, Losey and Vaughan (2006) estimated that native pollinators, almost exclusively bees, were responsible for US$3.07 billion of fruits and vegetables produced. Estimates of the value of species other than the honey bee are few, but the solitary bee (Megachile rotundata) — the major pollinator of alfalfa — contributed US$5.26 billion to the value of alfalfa hay in 2009 (Calderone, 2012). In the UK, the value of insect pollination was estimated at £603 million per year in 2010 (Hanley et al., 2013), while the UK NEA noted that many field crops (e.g. oilseed rape, linseed), top fruits (e.g. apples, pears, plums), soft fruits (e.g. strawberries, raspberries, blackcurrants) and vegetables (e.g. tomatoes and peas) are dependent, at least in part, on insect pollination. A recent study of the value of pollination to UK apple production showed that insects were essential for the two varieties studied and contributed £36.7 million per annum (Garratt et al., 2014). In Ireland, the economic value of insect pollination to oilseed rape was estimated at an overall value of €3.9 million per annum (Stanley et al., 2013).
The range of impacts that is considered in the report extends well beyond the considerations evaluated by the U.S. Environmental Protections when it conducts risk analysis under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) or when the U.S. Department of Agriculture considers the deregulation of genetically engineered crops under the Plant Protection Act. What is missing is an analysis of the pesticides to be used in herbicide-tolerant cropping systems that are harmful to biodiversity and ultimately plant health. The range of diversity factors as it relates to agricultural productivity includes: pollination, natural pest control, maintenance of soil fertility and farmland biodiversity and its supporting habitats, as well as flowering plants, arthropods, birds and mammals (as well as other invertebrates, fungi, protists and prokaryotes), and maintaining farmland biodiversity. According to the report, “Biodiversity and associated ecosystem processes provide ecosystem services, with many species involved in delivering more than one ecosystem service. However, overall trends in abundance and species richness for many farmland species are downward or uncertain.” The report addresses the range of species in some detail.
As a persistent pesticide, neonicotinoids disrupts the function of the soil food web, which is important ecosystem service, according to the report. The report explains that, “The soil decomposer food web plays an essential role in key ecosystem services such as soil formation, nutrient cycling and soil carbon storage (de Vries et al., 2013). In natural ecosystems, a substantial majority of primary production enters the soil where it is gradually decomposed and turned into nutrients and carbon dioxide which returns to the atmosphere. At the same time, the decomposer food web contributes to stabilisation of soil organic matter, which forms an important pool of carbon (soil contains about three times as much carbon as the atmosphere) and contributes to formation of soil aggregates and other structures essential for soil services such as water retention and purification, control of greenhouse gas emissions and erosion control (MEA, 2005).”
While defenders of neonicotinoids repeatedly point to the varroa mite and viruses as key factors in bee decline, the report indicates a concern about the increased vulnerability of bees to these factors caused by the chemicals. The report says,” Several studies have demonstrated synergistic effects of neonicotinoid residues with bee parasites and viruses. Some effects are behavioural (e.g. blocking the ability of bees to sterilise the colony and their food). Others appear related to limiting the immune response leading either to earlier infection or to increased mortality from infection. Very recent work has shown that the limitation of the immune response after exposure to neonicotinoids can promote viral replication, allowing covert infections to become overt. Such effects reduce honey bee survival and increase developmental deformities. In view of the emphasis placed by some reviewers on assigning honey bee losses to diseases and parasites, this is a critical issue
Importantly, while advocates of neonicotinoid use often tout the benefits of integrated pest management (IPM), as a credential for sensitivity to environmental concerns, the report indicates that the general principles of IPM appear to be “incompatible with the prophylactic use of neonicotinoids in seed dressing because of the following:
Ӣ only a small proportion of the insecticide enters the plant and most is released into the environment immediately;
Ӣ neonicotinoids may be applied proactively, not reactively based on just-in-time-and-place monitoring of the need for pest control; and the first priority is placed on chemicals instead of seeing them as a last resort;
”¢ principle 5 (which specifies that ”˜the pesticides applied shall be as specific as possible for the target and shall have the least side effects on human health, non-target organisms and the environment’) is also inconsistent with the many toxic effects reported for neonicotinoids on non-target organisms.
This report provides a thorough analysis, with references, of the harm that neonicotinoids wreak on biodiversity and the scientific basis for advocates who argue that they should be suspended from use.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
