Overige insecten

One of the best ways to support healthy hives and pollinator protection is to provide ample foraging. Keeping a
garden that provides not just nectar, pollen, and habitats, but also refrains from using toxic pesticides will go a long way towards helping bees and other pollinators. The most widely used garden insecticides are a class of chemicals called neonicotinoids. Attached is a list of common home and garden products containing neonicotinoids.

That this House welcomes the publication of The State of Britain's Larger Moths 2013 (attached), produced by Butterfly Conservation and Rothamsted Research; notes that Britain's moth population has declined seriously in the last 40 years, with over 60 species becoming extinct since 1900; recognises that the findings have serious implications for biodiversity, moths facilitating the pollination of many plants, constituting food for many animals, and acting as indicators of the impact of habitat loss, land-use intensification and global warming; and calls on the Government to ensure that steps are taken by all relevant departments and agencies to reverse the declines highlighted by the report and that funding is found to support concerted action for threatened moths especially those listed in section 41 of the Natural Environment and Rural Communities Act 2006, and to ensure continuation of Rothamsted Research's long-running data collection on the moth population in the UK.

Using the aquatic species Daphnia, commonly referred to as “water fleas,” scientists at North Carolina State University (NC State) determined that exposure to the insecticide pyriproxyfen impacted multiple generations, ultimately resulting in more male offspring, and causing reproductive problems in female offspring. Lead author Gerald LeBlanc, PhD, notes, “This work supports the hypothesis that exposure to some environmental chemicals during sensitive periods of development can cause significant health problems for those organisms later in life –and affect their offspring and, possibly, their offspring’s offspring.” The study, published in the journal PLoS One, provides the scientific community with new information on how organisms respond to the environmental signals resulting from pesticide exposure.

The present study evaluated the acute and chronic toxicity of imidacloprid to a range of freshwater arthropods. Mayfly and caddisfly species were most sensitive to short-term imidacloprid exposures (10 tests), whereas the mayflies showed by far the most sensitive response to long-term exposure of all seven arthropod species tested (28-d EC10 values of approximately 0.03 µg/L). The results indicated a high aquatic risk of chronic exposure of imidacloprid to mayflies.

Neonicotinoids are widely used systemic insecticides which, when applied to flowering crops, are translocated to the nectar and pollen where they may impact upon pollinators. Given global concerns over pollinator declines, this potential impact has recently received much attention. Field exposure of pollinators to neonicotinoids depends on the concentrations present in flowering crops and the degree to which pollinators choose to feed upon them. Here we describe a simple experiment using paired yellow pan traps with or without insecticide to assess whether the commonly used neonicotinoid imidacloprid repels or attracts flying insects. Both Diptera and Coleoptera exhibited marked avoidance of traps containing imidacloprid at a field-realistic dose of 1 µg L−1, with Diptera avoiding concentrations as low as 0.01 µg L−1. This is to our knowledge the first evidence for any biological activity at such low concentrations, which are below the limits of laboratory detection using most commonly available techniques. Catch of spiders in pan traps was also slightly reduced by the highest concentrations of imidacloprid used (1 µg L−1), but catch was increased by lower concentrations. It remains to be seen if the repellent effect on insects occurs when neonicotinoids are present in real flowers, but if so then this could have implications for exposure of pollinators to neonicotinoids and for crop pollination.

Changes in arable farming practices have been identified as important factors in the decline of wildlife. Significant declines in the brown hare have been recorded, associated with changes in the availability of high quality food at certain times of year. Declines in the Pipistrelle Bat are in part likely to have resulted from lower abundance of insect prey in farmland. Information on the decline of arthropods in farmland habitats has been published by the Game Conservancy Trust’s Sussex Study In the Sussex study area, between 1972 and 1990, arthropods have declined by 4.2% per annum (excluding springtails and mites), with many groups of beneficial insects, such as aphid predators and game bird food items, declining at faster rates. Bee species are particularly threatened. A range of cornfield weeds, such as corn buttercup and shepherd’s-needle, have declined markedly this century, to the extent that some species are now extinct in the UK. These annual flowers are dependent on the arable ecosystem, which is characterised by regular soil cultivation. Declines in farmland birds have been identified for a number of species characteristic of arable and mixed farmland. These birds feed on seeds, invertebrates or both, sometimes at different times of year.

This paper studied the arthropod community structure and its seasonal dynamics in alfalfa field under effects of imidacloprid. The results showed that imidacloprid more affected the species number of natural enemies rather than that of insect pests, resulting in a significant increase of the dominance concentration of both total arthropod community and pest sub-community. The numbers of dominant pests such as aphid and thrip reduced significantly at the initial stage of spraying imidacloprid, increased rapidly after 7 days, and exceeded the control after 40 days. As for the natural enemy sub-community, its species number decreased greatly and its species diversity and evenness were lower at the initial stage of spraying imidacloprid, its species number increased gradually after 7 days and approached to the level of the control thereafter, while its individual number was lower than the control all the time.

It has been postulated that a general decline in insect abundance linked with intensification of agriculture may have contributed to farmland bird decline. We analysed insect catch data from a single suction trap run for 27 years in a rural location in Scotland, and showed that insect numbers have changed significantly over time. Measures of bird density were significantly related to insect abundance. These data from a broad suite of species provide support for linked temporal change between farmland birds, invertebrate numbers and agricultural practice in Scotland.

The Government must introduce a precautionary moratorium on three pesticides linked to the decline of pollinators - imidacloprid, clothianidin and TMX – that suspends their use on flowering crops attractive to pollinators, Parliament’s cross-party green watchdog has said. Environmental Audit Committee Chair, Joan Walley MP, commented: “Defra seems to be taking an extraordinarily complacent approach to protecting bees given the vital free service that pollinators provide to our economy. If farmers had to pollinate fruit and vegetables without the help of insects it would cost hundreds of millions of pounds and we would all be stung by rising food prices. Defra Ministers have refused to back EU efforts to protect pollinators and can’t even come up with a convincing plan to encourage bee-friendly farming in the UK.” Two-thirds of wild insect pollinator species - such as bumblebees, hoverflies, butterflies, carrion flies, beetles, midges and moths - have suffered population declines in the UK. Managed honeybees have also experienced unusually high mortality rates, decreased fertility, increased susceptibility to disease and the loss of hives. Similar trends have been observed in the US and other European countries.

Surface runoff is an important process that affects the local water balance and causes soil erosion and rapid solute transport towards ditches, streams, and rivers. Surface runoff is the fastest route from field to stream and the main transport route for sediment and adsorbed contaminants, such as pesticides. It is the main contributor of pesticides to surface water bodies. The agricultural areas in The Netherlands most vulnerable to surface runoff are peat grasslands, where groundwater levels are kept close to the surface (less than 60 cm below soil surface), riverine heavy clay grasslands with low permeability and drainage by superficial trenches (less than 40 cm below soil surface), and sandy or clay soils with topsoil or subsoil compaction caused by treading, overstress due to large wheel loads of agricultural machinery, and tillage.