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The eastern spruce budworm, Choristoneura fumiferana Clem., (hereafter budworm) is responsible for the largest areas of insect-caused disturbance in North America, and as such, is an important part of spruce–fir forest change and succession. The insectivorous forest bird community shows large and rapid responses to budworm outbreaks. There is good evidence that there are budworm-linked species (bay-breasted, Cape May, and Tennessee warblers) that respond to budworm outbreak much more strongly and consistently than other species, probably through increased productivity of local populations when budworm are abundant. There also appears to be a more widespread positive bird community response to budworm outbreak that involves many more species.

Neonicotinoid insecticides like thiacloprid enter agricultural surface waters, where they may affect predator-prey interactions, which are of central importance for ecosystems as well as the functions these systems provide. The effects of field relevant thiacloprid concentrations on the leaf consumption of Gammarus fossarum (Amphipoda) were assessed over 96 h (n = 13-17) in conjunction with its predation on Baetis rhodani (Ephemeroptera) nymphs. The predation by Gammarus increased significantly at 0.50-1.00 ug/L. Simultaneously, its leaf consumption decreased with increasing thiacloprid concentration. As a consequence of the increased predation at 1.00 ug/L, gammarids’ dry weight rose significantly by 15% compared to the control. At 4.00 ug/L, the reduced leaf consumption was not compensated by an increase in predation causing a significantly reduced dry weight of Gammarus (~20%). These results may finally suggest that thiacloprid adversely affects trophic interactions, potentially translating into alterations in ecosystem functions, like leaf litter breakdown and aquatic terrestrial subsidies.

Most literature on birds and rice (Oryza sativa) focuses on the non-growing period and little is known about the influence of management practices during cultivation. A review found that the main factors affecting species composition and abundance in rice fields during the growing season were water level, flooding period, rice plant structure and size, and pesticide use. Highest bird density and diversity occurred at intermediate water levels (10–20 cm). Early flooding and late drying favored waterbird density and diversity, and the stopover of migrating species. Taller plants, at higher densities, reduced prey availability to most waterbirds but favored smaller species. Pesticides and herbicides have been shown to be toxic to birds and reduce food resources.

Invertebrates are an essential food source for most farmland birds yet their relative abundance and biomass in the most commonly grown arable crops are poorly understood. Dvac suction sampling was used to determine the abundance, biomass and community composition of those invertebrate groups considered important in the diet of farmland birds for the commonest arable crops. Approximately 40 fields were sampled at the edge and mid-field over 2 years in three different locations in England. In cereals, the fauna was primarily comprised of Araneae (10%), Coleoptera (30%) and Hemiptera (58%), whereas the oilseed rape fauna was dominated by Coleoptera (65%) and peas and potatoes by Hemiptera (89%). Beans contained a high proportion of Coleoptera (39%) and Hemiptera (49%). Aphididae were the most abundant family (20–86% of total), although in oilseed rape and beans, Chrysomelidae, Curculionidae and Nitidulidae formed ca 20% of the fauna. Aphids only formed a small proportion (7%) of the total biomass, except in peas (32%).

During the past 50 years, the human population has more than doubled and global Agricultural production has similarly risen. However, the productive arable area has increased by just 10%; thus the increased use of pesticides has been a consequence of the demands of human population growth, and its impact has reached global significance. Although we often know a pesticide´s mode of action in the target species, we still largely do not understand the full impact of unintended side effects on wildlife, particularly at higher levels of biological organization: populations,
communities, and ecosystems. In these times of regional and global species declines, we are challenged with the task of causally linking knowledge about the molecular actions of pesticides to their possible interference with biological processes, in order to develop reliable predictions about the consequences of pesticide use, and misuse, in a rapidly changing world.

Great Smoky Mountains National Park is using systemic imidacloprid to treat eastern hemlocks (Tsuga canadensis [L.] Carr.) infested with the exotic insect, hemlock woolly adelgid (Adelges tsugae Annand). This study investigated effects of these treatments on insectivorous birds and hemlock canopy arthropod assemblages in the context of food availability for insectivorous birds. Six pairs of treated and untreated hemlock sites were studied in 2007. Territories of three hemlock-associated Neotropical migratory foliage-gleaning bird species were mapped in these six sites, and relationships between bird territory density and hemlock foliar density were examined. Canopy arthropods were sampled by clipping mid-canopy hemlock branches in each paired site. Arthropods were identified to order or suborder and categorized into bird prey guilds and non-target herbivorous insect guilds.

A study investigated whether cytogenetic damage increased through prolonged pesticide exposure in n = 117 children, aged 7-11 years, living in rural areas of intensive agriculture; controls being n = 87 children from an agri-tourism region without pesticide exposure. DNA Single-Strand Breaks (SSB) were detected by the Comet assay in whole fresh blood samples together with ‘formamidopyrimidine DNA-glycosylase (FPG)-sensitive sites' with the bacterial FPG protein in isolated lymphocytes. Micronuclei (MN) levels were measured by the cytokinesis-block MN assay. Acetylcholinoesterase (AChE) and Pseudocholinesterase (PChE) activities were used as biomarkers of exposure. Subjects exposed to pesticides had significantly higher AChE and PChE activities than controls, although average levels were well below the biological exposure limit. In addition, those exposed to pesticides had significantly higher levels of steady-state FPG sites and SSB levels (p < 0.001), as well as MN levels. A positive correlation was found between PChE activity and FPG-sensitive sites and also between MN levels and FPG-sensitive sites, (both p < 0.01). In conclusion, despite the relatively low pesticide exposures in the test group of children, significant biological/developmental effects were detected.

In 2006, New England states started observing a disturbing trend in the local population of bats — a fatal new fungus was killing off thousands of bats across several species lines. Seven years later, more is known about White Nose Syndrome, but the fungus that has decimated local bat populations continuous to vex researchers. And the impact is alarming: the small brown bat, once the most common bat in the Northeast, may not be found regionally within 12 years if the spread of the fungus can’t be contained.

Scientists from the RSPB, Scottish Natural Heritage (SNH) and Natural Research have revealed the startling decline in bird populations in the State of UK Birds 2013 report. The mountain species dotterel (Charadrius morinellus), one of the rarest breeds in Britain – with two-thirds living in the Cairngorms – has declined by about 40 per cent in just over a decade. The results found that the estimated number of dotterels had fallen from 630 breeding males in 1999, to just 423 breeding males in 2011, continuing a longer-term decline since the first survey in 1987-88, which estimated the number of breeding males at 981. Other declines of population include the lapwing, a bird of farmland and wetland which has endured a 41 per cent population decline since 1995. The snipe, a wetland bird, has seen its breeding range shrunk by 31 per cent over the last 40 years. The population of grey partridge – another farmland bird – has declined by 53 per cent since 1995, while the corn bunting population has declined by 34 per cent since 1995. The turtle dove, which is not native in Scotland, has suffered a 51 per cent decline in the rest of the UK over the last 40 years. Mark Eaton, of RSPB, said: “Scotland’s Highlands provide an important home for dotterel and the species’ presence offers a good indicator of the health of our mountain landscapes. To see such a significant drop in their numbers over the past three decades is deeply concerning.

Some of Britain's most familiar countryside birds have plummeted in numbers since the 1990s, and some species have disappeared from parts of the UK, according to an authoritative annual report. Numbers of the farmland-dwelling grey partridge have halved since 1995, while the turtle dove has declined by 95%. The yellow wagtail, which inhabits farm and wetland, has declined by 45% over the same period. The State of the UK's Birds report, from the RSPB, the British Trust for Ornithology (BTO), the Wildfowl & Wetlands Trust and several UK government nature bodies, shows that of the UK's 107 most widespread and common breeding birds, 16 species have declined by more than a third since 1995, including the willow tit, starling, cuckoo, lapwing and wood warbler.