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Animas River trout in decline. Fewer young browns particularly worrisome

The number of brown and rainbow trout in the Animas River swimming through Durango has declined, according to an ongoing study.In particular, a decline has been noted in fish from 32nd Street to the Lightner Creek confluence with the Animas, said Jim White an aquatic biologist with Colorado Parks and Wildlife, who worked on the fish survey. This is the first time the area hasn’t met the Gold Medal standard for large fish since 1996, White said. Colorado Parks and Wildlife stocks the Animas with both kinds of trout, and the stocking practices have not changed in about 20 years. However, the most recent survey in September revealed a worrisome decline in both young and large brown trout compared with prior years, White said. “We’re concerned over the absence of these young brown trout,” he said.

The Steep Decline of Atlantic Coast Swallows

There are four species of swallows found in Maritime Canada: bank swallow (Riparia riparia), barn swallow (Hirundo rustica), cliff swallow (Petrochelidon pyrrhonota) and tree swallow (Tachycineta bicolor). Population trends for these species and other aerial insectivores (birds that feed almost exclusively on flying insects while in flight) show rapid declines in the last 40 years. These declines are greater than any other group of birds in North America and are particularly severe in northeastern North America.The total population size of each species is unknown, but over the last 40 years there have been significant population declines and these declines are greatest in the Maritimes. It is estimated that bank swallow population in Canada has declined by 98%, with 31% lost in the last 10 years. The rate of decline is similar for the barn swallow, with a loss of 75% of the population, including 30% in just the last 10 years.

Reflections on Christmas Day - The Vital Legacy of John Muir (1838-1914)

Humanity is the product of the same processes as all other species that have dwelt on Earth, with our well-being inextricably tied to the health of the biosphere. Contemporary science has confirmed nature’s myriad links, but as early as 1911 John Muir poetically expressed ecology’s central insight. “When we try to pick out anything by itself,” Muir wrote in My First Summer in the Sierra, “we find it hitched to everything else in the Universe.” The twin ideas of evolutionary kinship and ecological connectivity are profoundly disruptive to the delusion of human exceptionalism, that somehow the rules don’t apply to us, that our cleverness is boundless, even to the point of transcending biological limits. One hundred years after his death, John Muir’s legacy could not be more vital. Inspired by the love he felt for the wild world, today’s vision for the future of conservation—and the future of the Earth—is one of planetary rewilding, where a scaled-back human civilization is embedded in a matrix of wildness, and where at least half of the globe is left to nature. It is a vision both idealistic and achievable: Broad swaths of green and blue— beautiful, untrammeled, evolution-supporting lands and waters encircling the Earth, where wild life and people flourish together.

Another insectivorous bird facing extinction in the US

When they’re not dining on the population explosions of caterpillars, they eat other insects, frogs, lizards, crickets, cicadas and other streamside dwellers. They’ve almost vanished from the Southwest — including Arizona. So the U.S. Fish and Wildlife Service wants to list the wide-ranging, quickly-disappearing, stream-loving western yellow-billed cuckcoo (Coccyzus americanus) as an endangered species — likely adding one more layer of protection for — and restrictions on — streams in Rim Country. The federal government has proposed listing 80 protected streamside areas as critical habitat for the robin-sized bird, including Tonto Creek, the Verde River and other small streams like the East Verde, Fossil Creek and other Rim Country streams. Population surveys suggest the Western Cuckcoo continues to decline by about 1.5 percent annually. The estimated 15,000 breeding pairs in California in the late 19th century had declined to about 30 pairs by 1986. The thousands of pairs in Arizona had declined to 200 pairs in the same period. Biologists aren’t sure how many pairs remain in the southwest now.

Impact of a widely used insecticide on soil microorganisms - nitrifying and N2-fixing bacteria are sensitive to imidacloprid

Imidacloprid is one of the most commonly used insecticides in agricultural practice, and its application poses a potential risk for soil microorganisms. The objective of this study was to assess whether changes in the structure of the soil microbial community after imidacloprid application at the field rate (FR, 1 mg/kg soil) and 10 times the FR (10 × FR, 10 mg/kg soil) may also have an impact on biochemical and microbial soil functioning. The obtained data showed a negative effect by imidacloprid applied at the FR dosage for substrate-induced respiration (SIR), the number of total bacteria, dehydrogenase (DHA), both phosphatases (PHOS-H and PHOS-OH), and urease (URE) at the beginning of the experiment. In 10 × FR treated soil, decreased activity of SIR, DHA, PHOS-OH and PHOS-H was observed over the experimental period. Nitrifying and N2-fixing bacteria were the most sensitive to imidacloprid. The concentration of NO3− decreased in both imidacloprid-treated soils, whereas the concentration of NH4+ in soil with 10 × FR was higher than in the control. Analysis of the bacterial growth strategy revealed that imidacloprid affected the r- or K-type bacterial classes as indicated also by the decreased eco-physiological (EP) index. Imidacloprid affected the physiological state of culturable bacteria and caused a reduction in the rate of colony formation as well as a prolonged time for growth. Principal component analysis showed that imidacloprid application significantly shifted the measured parameters, and the application of imidacloprid may pose a potential risk to the biochemical and microbial activity of soils.

How pesticides (neonicotinoids) change navigation, recruitment, and learning behavior of bees

Navigation in honeybees is studied with the help of a special radar that allows to trace the flights of individual bees over kilometers. In a typical experiment, the bees were trained to a feeder or they follow a dancing bee. Then we equipped one bee with a radar transponder and released it at a site within the range of the explored area. First, the animal performs a straight flight that would have brought it back from the feeder to the hive (vector flight) would it not have been transported to a different site. In the case of the dance follower, the bee performs the vector information transmitted in the dance, as described by Karl von Frisch and followers. Then the bee loops around (search flight), followed by a straight return flight to the hive (homing flight). We carried out the experiments in an area where the skyline of the horizon or a beacon at the hive did not guide the bees’ navigation. Thus, the bees referred only to the pattern of landmarks on the ground. We show that the memory structure used by the bees can be best conceptualized as a cognitive map storing the geometric relations of landmarks and important locations. Sublethal doses of neonicotinoids interfere selectively with the homing flight component based on this cognitive map memory, reducing the probability of successful returns to the hive. Chronic exposure to the neonicotinoid Thiacloprid reduces the attractiveness of a feeding site and the rate of recruitment.

Neonicotinoid-Contaminated Puddles of Water Represent a Risk of Intoxication for Honey Bees

In recent years, populations of honey bees and other pollinators have been reported to be in decline worldwide. A number of stressors have been identified as potential contributing factors, including the extensive prophylactic use of neonicotinoid insecticides, which are highly toxic to bees, in agriculture. While multiple routes of exposure to these systemic insecticides have been documented for honey bees, contamination from puddle water has not been investigated. In this study, we used a multi-residue method based on LC-MS/MS to analyze samples of puddle water taken in the field during the planting of treated corn and one month later. If honey bees were to collect and drink water from these puddles, our results showed that they would be exposed to various agricultural pesticides. All water samples collected from corn fields were contaminated with at least one neonicotinoid compound, although most contained more than one systemic insecticide. Concentrations of neonicotinoids were higher in early spring, indicating that emission and drifting of contaminated dust during sowing raises contamination levels of puddles. Although the overall average acute risk of drinking water from puddles was relatively low, concentrations of neonicotinoids ranged from 0.01 to 63 µg/L and were sufficient to potentially elicit a wide array of sublethal effects in individuals and colony alike. Our results also suggest that risk assessment of honey bee water resources underestimates the foragers' exposure and consequently miscalculates the risk. In fact, our data shows that honey bees and native pollinators are facing unprecedented cumulative exposure to these insecticides from combined residues in pollen, nectar and water. These findings not only document the impact of this route of exposure for honey bees, they also have implications for the cultivation of a wide variety of crops for which the extensive use of neonicotinoids is currently promoted.

An Overview Comparing Results from Two Decades of Monitoring for Pesticides in the Nation’s Streams and Rivers, 1992–2001 and 2002–2011

This report provides an overview of the U.S. Geological Survey National Water-Quality Assessment program and National Stream Quality Accounting Network findings for pesticide occurrence in U.S. streams and rivers during 2002–11 and compares them to findings for the previous decade (1992–2001). In addition, pesticide stream concentrations were compared to Human Health Benchmarks (HHBs) and chronic Aquatic Life Benchmarks (ALBs). The comparisons between the decades were intended to be simple and descriptive. Trends over time are being evaluated separately in a series of studies involving rigorous trend analysis. During both decades, one or more pesticides or pesticide degradates were detected more than 90 percent of the time in streams across all types of land uses. For individual pesticides during 2002–11, atrazine (and degradate, deethylatrazine), carbaryl, fipronil (and degradates), metolachlor, prometon, and simazine were detected in streams more than 50 percent of the time. In contrast, alachlor, chlorpyrifos, cyanazine, diazinon, EPTC, Dacthal, and tebuthiuron were detected less frequently in streams during the second decade than during the first decade.

Pesticides in U.S. Streams and Rivers: Occurrence and Trends during 1992–2011

During the 20 years from 1992 to 2011, pesticides were found at concentrations that exceeded aquatic-life benchmarks in many rivers and streams that drain agricultural, urban, and mixed-land use watersheds. Overall, the proportions of assessed streams with one or more pesticides that exceeded an aquatic-life benchmark were very similar between the two decades for agricultural (69% during 1992−2001 compared to 61% during 2002−2011) and mixed-land-use streams (45% compared to 46%). Urban streams, in contrast, increased from 53% during 1992−2011 to 90% during 2002−2011, largely because of fipronil and dichlorvos. The potential for adverse effects on aquatic life is likely greater than these results indicate because potentially important pesticide compounds were not included in the assessment. Human-health benchmarks were much less frequently exceeded, and during 2002−2011, only one agricultural stream and no urban or mixed-land-use streams exceeded human-health benchmarks for any of the measured pesticides. Widespread trends in pesticide concentrations, some downward and some upward, occurred in response to shifts in use patterns primarily driven by regulatory changes and introductions of new pesticides.

Finnish water fowl populations plummet

The populations of most types of Finnish water fowl have been declining steadily and aggressively for many years, a new study shows. The results of the study, conducted by the Finnish Game and Fisheries Research Institute (RKTL) and the Finnish Museum of Natural History, were published in the European Journal of Wildlife Research. Species of water bird whose numbers are swiftly dwindling include the widgeon (Anas penelope), the northern pintail (Anas acuta), the garganey (Anas querquedula), the tufted duck (Aythya fuligula), the pochard (Aythya ferina) and the coot (Fulica atra). Researchers say the drops are due to changes in the birds’ habitat; feeding becomes difficult for water fowl in hypertrophic or polluted waters. The research centre calls the population depletion a ”mystery,” since extra nutrients in the waters should make it easier for birds to feed. Shifts in the food chain may also affect the nutritional intake of young fowls, and small mammalian predators or other birds can eat the young of other species or destroy their nests.