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In this study, we used two different types of bioassay, a contact filter paper toxicity bioassay and a soil toxicity bioassay, to compare the acute toxicity of twenty-four insecticides belonging to six chemical categories on earthworm species, Eisenia fetida. It was concluded that irrespective of bioassay systems, earthworms were more susceptible to neonicotinoids than to other modern synthetic insecticides.

Parts per billion of neonicotinoids in pollen are indeed infinitesimal, but they do cause adverse effects on honeybees. Luc Belzunces, a bee researcher at INRA (the French Agricultural Research Institute) in Avignon published “Discrepancy between acute and chronic toxicity induced by imidacloprid and its metabolites in Apis mellifera” (Environ. Toxicol. Chem. 20(11):2482-6) in 2001. He found an acute lethal dose of imidacloprid of only 40 nanogram per bee, much less than most other insecticides. However, his big discovery was that the lethal dose from chronic exposure to imidacloprid was 4,000 times less, “Ingesting 1 picogram a day was enough to kill a bee within 10 days”, he told INRA magazine (June 2009). “Moreover, imidacloprid degrades into 6 metabolites, some of which are even more toxic.” He said that the capacity to measure very small traces of imidacloprid in pollen now shows that the concentration is in the range of microgrammes per kg (parts per billion) of pollen and that this constitutes a risk for bees.

Luc Belzunces' conclusion was subsequently substantiated by Dr Jeff Pettis of the US Agricultural Research Service and his colleagues (published in 2012 in Naturwissenschaften DOI 10.1007/s00114-011-0881-1). Since one thing common to bee colonies that go on to collapse seems to be a greater variety and higher load of parasites and pathogens than other colonies, they wondered in particular whether neonicotinoids might be weakening the insects’ immune systems, and thus allowing infections to spread through a hive. To find out, they gave 20 hives protein food (a substitute for pollen, which is fed to developing larvae) that had been spiked with imidacloprid. In ten cases the dose was five parts per billion (ppb); in the other ten it was 20 ppb. Previous experiments have shown that neither dose perceptibly harms bees. A further ten hives were given un-spiked food as a control. Then, when the young bees emerged a few weeks later, Dr Pettis collected them and fed them with spores of a fungal parasite called Nosema. Twelve days later, he killed them and estimated the extent of their infestation. Both of the groups that had been exposed to imidacloprid harboured an average of 700,000 parasite spores in each bee. Bees from the control colonies, by contrast, harboured fewer than 200,000 spores in their bodies. The insecticide, in other words, was exposing bees to infestation, and thus to a much greater chance of dying prematurely. Similar results had been published by Cédric Alaux and his colleagues from France in 2010 (Environ. Microbiol. 12(3): 774–782). Vidau et al. (2011) showed that exposure to sublethal doses of fipronil and thiacloprid highly increased the mortality of honeybees previously infected by Nosema ceranae. PLoS ONE 6 (6):e21550.

An iconic but little-known Adirondack bird is dipping toward extinction in the state and likely can only be saved by bringing birds from Canada or other states to strengthen breeding. That is the conclusion of a new study on spruce grouse (Falcipennis canadensis), a bird common in Canada but much less so in New York and the Northeast. After decades of decline, there are now just 100 or fewer specimens in three Adirondack counties. At the turn of the century, the bird occupied as many as seven Adirondack counties. As recently as the 1970s, there were an estimated 300 birds, but numbers have steadily dwindled. The bird is now on the state endangered species list."We need to do something real soon, in the next few years," said John Ozard, head of wildlife diversity for the state Department of Environmental Conservation. Otherwise, odds now are 1-in-3 that spruce grouse will disappear from the Adirondacks by 2020, according to a DEC study released Friday.

Residents and staff of Pentlow Nursing Home took part in the Big Garden Birdwatch on January 28th and 29th - the world’s biggest bird survey organised by the RSPB. Disappointingly, for the second consecutive year, there were no sparrows recorded by residents. According to the RSPB the country has lost more than half its house sparrows Passer domesticus, and three-quarters of its starlings Sturnus vulgaris. Lesley Wick, manager at Pentlow Nursing Home, said: “Our residents really enjoy our garden and part of that enjoyment is the bird life. We have reported our findings back to the RSPB, which helps create a 'snapshot' of bird numbers in each region and highlight any dramatic declines.”

A threatened bird, rarely seen in the south, has been recorded and ringed by the West Wilts Bird Ringing Group. Volunteers, who were working in Wiltshire Wildlife Trust’s Ravens-roost Wood nature reserve, near Malmesbury, recorded and ringed a first-year male lesser spotted woodpecker Dendrocopos minor – the smallest and rarest of the three woodpeckers which can be found in Britain. Once common, the tiny woodpeckers are said to have suffered a massive decline of over 50 per cent in the past 25 years. According to the RSPB, there are only about 1,400-2,900 breeding pairs of lesser spotted woodpeckers in the UK.

Bacteria have led to the death of hundreds of millions of house finches since they jumped species and started an epidemic in the 1990s. Mycoplasma gallisepticum infected poultry before it adapted to the house finch Carpodacus mexicanus population. The bacteria are responsible for the red, swollen, crusty eyes of a sick house finch, which leaves it unable to survive.

As an aid to testing hypotheses for the causes of colony failure we have developed a compartment model of honey bee colony population dynamics to explore the impact of different death rates of forager bees on colony growth and development. The model predicts a critical threshold forager death rate beneath which colonies regulate a stable population size. If death rates are sustained higher than this threshold rapid population decline is predicted and colony failure is inevitable. The model also predicts that high forager death rates draw hive bees into the foraging population at much younger ages than normal, which acts to accelerate colony failure.

I haven’t seen a little owl for a while, and on checking my records on Birdtrack I am slightly surprised to find that I didn’t see a little owl Athene noctua in either 2011 or 2010 so it really is some time ago. So the next question has to be – is it just me? The State of the UK’s Birds for 2011 shows that little owls have decined in numbers by 40% in the last 40 years, with most of that decline since 1990. So it’s probably not just me. Given that little owls are farmland species that depend on invertebrates such as large insects and earthworms it may not be surprising that they are declining but I expect someone will blame their decline on the badger if we wait long enough!