English

Imidacloprid was shown to act as both a larvicide and an adulticide in studies on cat fleas. Due to its probable main uptake by the flea through the nonsclerotized intersegmental membranes it rapidly reaches the site of action: the postsynaptic membrane. There, the irreversible blocking of the nACh receptors leads to a lethal hyperactivity of the nerves and muscles of the insect. Both stages are sensitive to the drug, and after contact they react in a similar fashion: they stop their jumping or (respectively) crawling movements and display the onset of rhythmic trembling of the legs and the body. This nonreversible phenomenon finally leads to the death of both flea stages. These easily visible effects correspond to the finding that imidacloprid blocks the postsynaptical nicotinic acetylcholine receptors (Abbink 1991). The latter are normally stimulated by acetylcholine that is excreted into the synaptic gap. These receptors initiate the opening of channels in the membrane to let Na+ flow into the cell. This leads to a depolarization of the terminal plate and induces the activation of an action potential. The latter causes the release of Ca2+ from vesicles and thus results in contraction of the myosin/actin complex of the sarcomeres. In normal cases the acetylcholine has a brief connection to the receptor, is subsequently released, and is rapidly hydrolyzed by a membrane-bound cholinesterase. In the case of imidacloprid the binding of the compound and the receptors is stronger; hence, a constant depolarization of the membrane occurs, inducing a tetanus of the activated muscle cell. This mode of action corresponds to the structural findings described herein, since the observed degeneration mainly involved an overall destruction of the mitochondria, damage to the nerve cells, and disintegration of the muscle, Imidacloprid initiates a constant depolarization of the nerves, which is followed by a constant activation of the muscles until the cellular energy systems (mitochondria, glycogen) are depleted and the motile proteins are destroyed.

The results show that, in the same two areas, sampled in the years 1989 and 2013, there was a dramatic fall in the number of flying insects. Using the same traps, in the same areas, significant reductions of insect populations, of more than 75%, were found. Our data confirms, that in the areas studied, less than 25% of the original number of flying insects collected in 1989, were still present in 2013.

Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long-term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long-term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long-term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change.

This is the analysis of the latest assessment of the Red List of Birds for Finland, published in January. Of the 245 Finnish breeding species evaluated, 87 (36%) are Threatened and 23 (9%) are Near Threatened. Of the Threatened species, 13 (5%) are Critically Endangered, 36 (16%) are Endangered, and 38 (16%) are Vulnerable. The numbers have gone up from the last evaluation: In 2010, 59 species (24%) were Threatened and 30 (13%) were Near Threatened. This time, 110 species (45% of all Finnish breeding species) are on the Red List, up from 89 (about 36%) in 2010 and 72 in 2000. The state of water and wetland birds is the most concerning. Half of the Finnish breeding waterbirds and nearly half of the waders are now threatened. Populations of the Tufted Duck, Garganey, Eurasian Wigeon and Northern Pintail have decreased sharply in the last decades. The situation is alarming not only for conservationists and birdwatchers, but also for hunters. Eleven out of the 17 game waterbirds in Finland are now red-listed because of a decline in population: six are Endangered, four are Vulnerable and one is Near Threatened. The number of species which can be hunted sustainably in Finland has collapsed.

A fisheries expert is warning two species unique to south-west Western Australia could face extinction. The populations of the state's only two species of aestivating fish, the salamanderfish (Lepidogalaxias salamandroides) and black stripe minnow (Galaxiella nigrostriata), which burrow into the ground and become dormant over summer, have been dramatically reduced. The ability to aestivate is similar to hibernation. Murdoch University researcher Garry Ogston said the salamanderfish was the only one of its type in the country. "In terms of the ability to aestivate, they're the only two species that do that in all of Western Australia," he said. "Some other fish species do it around the world but it's not a very typical trait, it's quite a rare trait. The salamander fish itself is actually the only member of its family, lepidogalaxias, so there are no other members related to it in that family out of any other fish anywhere in the world. He said if no action was taken, both species, which were most common around Northcliffe, were likely to disappear. "They've had quite a large range reduction, they were lost from a lot of their sites which were previously historical presence records," he said. "It was in the order of around 80 per cent for salamanderfish and just over 50 per cent for black stripe minnows, which was quite alarming. Many of the wetlands home to salamanderfish and black stripe minnow are in conservation reserves, however, others border farmlands, so working with landowners regarding fertiliser run-off, and restricting access for livestock would also be key in helping protect these pools."

The Devon Bird Atlas 2016 - unveiled today at Stover Park, near Newton Abbot - shows that since the first Atlas was published in 1988 eight species have disappeared from the county and 60 have suffered declines. The nightingale, much-loved for its beautiful song, has been lost as a breeding bird in Devon. "It is a great sadness that this wonderful songster may never be heard again in Devon," the reports authors warn. Other birds facing serious declines include the cuckoo which has seen one of the largest declines since the publication of the first Atlas in 1988. It now breeds in only 372 tetrads (2km x 2km squares on the map) compared to 1,447 in the 1977–1985 survey. Breeding Cuckoos are now almost exclusively confined to Dartmoor. The reduction in Lapwing numbers is particularly striking in Devon. Previously widespread across the county, this latest survey shows that breeding is now restricted to just two sites - the Exe Estuary RSPB reserves and southern Dartmoor. Skylarks have seen a huge decline from being recorded as breeding in 93% of the county of Devon in 1988 to only 63% during the 2007–2013 survey period.

During the growing season, neonicotinoid insecticides are frequently transported to surface water systems after rainfall events. However, detectable levels of neonicotinoids have also been found in wetlands during early spring, after ice-off but before crop seeding, representing an unexpected long-term exposure risk for aquatic organisms. This suggests long-term persistence, though origins and transport mechanisms remain unknown. We sampled 16 agricultural fields in the Canadian Prairies to investigate whether snow meltwater, particulate matter, top- (15 cm) or bottom-layer (15 cm) snow were potential sources of spring neonicotinoid contamination to receiving wetlands. Agricultural fields were selected based on the previous year’s crop: eight canola fields (clothianidin-treated seed) and eight oat fields (un-treated). We further sampled the wetlands draining those same oat and canola fields from ice-off to seeding to assess changes in neonicotinoid concentrations over time. Top-layer snow was below the limit of quantification for both canola and oat fields. Neonicotinoid concentrations (sum of clothianidin and thiamethoxam) were highest in meltwater (canola, mean: 267 ± 72.2 ng L−1; max: 633), but also detected in bottom-layer snow (oat, mean: 36.1 ± 9.18 ng L−1; max: 92.9), and soil particulate matter (canola, mean: 10.2 ± 1.82 μg/kg; max: 17.2). Concentrations in meltwater showed a stronger relationship (R2 = 0.35) with initial concentrations in wetland water than any other source type. Temporary wetland hydrology is largely fed by meltwater thus spring total neonicotinoid concentrations were higher in temporary wetlands than seasonal/semi-permanent wetlands (P = 0.003). Only clothianidin was detected in soil particulate matter samples, including from oat fields not treated the year before, confirming this compound can persist over multiple years under local field conditions. The results of this study suggest that under normal agricultural practices, wetlands in colder climates are likely to be contaminated even before seeding occurs through persistence of neonicotinoids in soil and transport by snowmelt and particulate to surface water during spring runoff.

Like many other area farmers, the Bredeson family in Harvey Township, between Grove City and Litchfield, buys corn and soybeans seeds treated with pesticides. Pesticides are designed to improve crop yields, but they have side effects, and the family has been learning more about these effects from an expert — Mark and Julie Bredeson’s own son, Michael. “He’s kind of on the cutting edge of finding that these pesticides that farmers have been using for many years have become a detrimental thing to not only agriculture but mother nature,” Julie said about Michael’s work. Michael, a 2008 Litchfield High School graduate, is pursuing his Ph.D. at South Dakota State University, where he studies the effects of pesticides on organisms, particularly linked to sunflowers, a common cash crop in South Dakota. In commentary in the Independent Review (see below), Michael writes about pesticides’ effects and the long-term implications for birds, reptiles, mammals, fish and plants. Julie and Michael said they’ve both noticed a reduction in wildlife at and near the family’s Meeker County farm over the years. As he grew older, Michael noticed a decline in good fishing holes, which he attributes to runoff from crop fields. “My life revolved around fishing on all the little lakes. A few of my great fishing spots died off, and that kind of irritated me, of course,” he said. Julie said she’s also witnessed a decline in wildlife since she was a child. “The landscape as far as our wildlife, butterflies and bees, has dramatically changed,” she said. “It’s something we need to think about.”

Even though an insect-free world sounds great to most people, it world would be detrimental to our environment in many ways. First, there we would see the starvation of insect-eating animals such as frogs, moles, birds, lizards, and spiders who feed off insects to stay alive. Next there would be the inability to naturally recycle materials through composting which reintroduces nutrients into the soil. Our world would be buried in waste from all the trash we produce without insects such as beetles and their larvae, worm-like larvae, as well as true worms like night-crawlers. Another disadvantage would be the plummeting of crop yields due to lack of pollination. The honey bee alone is responsible for pollinating almonds, apples, avocados, blueberries, cantaloupes, cherries, cranberries, cucumbers, sunflowers, watermelon and many other crops. Last and most importantly there would be a collapse in the food chain. It has been said, “many plants would disappear without insect pollinators, and entire ecosystems would collapse in the absence of insects in the food chain.” A world without insects would be no world at all; we wouldn’t exist. However, even if our planet could exist, it would lack the wonder and beautiful that nature shows us everyday. People should think about the next they say, “I hate bugs,” for its because of bugs that we are alive.