The large‐scale removal of mammalian invasive alien species in Northern Europe

Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (<10 km²), but few from more extensive areas. We review 15 large‐scale removals (mean area 2627 km²) from Northern Europe since 1900, including edible dormouse, muskrat, coypu, Himalayan porcupine, Pallas' and grey squirrels and American mink, each primarily based on daily checking of static traps. Objectives included true eradication or complete removal to a buffer zone, as distinct from other programmes that involved local control to limit damage or spread. Twelve eradication/removal programmes (80%) were successful. Cost increased with and was best predicted by area, while the cost per unit area decreased; the number of individual animals removed did not add significantly to the model. Doubling the area controlled reduced cost per unit area by 10%, but there was no evidence that cost effectiveness had increased through time. Compared with small islands, larger‐scale programmes followed similar patterns of effort in relation to area. However, they brought challenges when defining boundaries and consequent uncertainties around costs, the definition of their objectives, confirmation of success and different considerations for managing recolonisation. Novel technologies or increased use of volunteers may reduce costs. Rapid response to new incursions is recommended as best practice rather than large‐scale control to reduce the environmental, financial and welfare costs. © 2016 Crown copyright. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

A single sea lamprey attack causes acute anemia and mortality in lake sturgeon

The effects of sea lamprey Petromyzon marinus parasitism on hematological variables have not been quantified for lake sturgeon Acipenser fulvescens. Our study objectives were to (1) assess changes in lake sturgeon hematology immediately after a single sea lamprey attack and after a 2-week recovery period and (2) assess changes in the histological condition of major hematopoietic organs. Lake sturgeon from four size-groups (470-570, 570-650, 650-760, and 950-1,500 mm fork length) were individually subjected to a sea lamprey attack in a series of 55 experimental trials. Survival of lake sturgeon after a single sea lamprey attack was size dependent, with fish in smaller size-groups exhibiting higher direct and indirect mortality than individuals in larger size-classes. The most sensitive blood chemistry variable was hematocrit: each 1% decline in hematocrit resulted in a 5.1% increase in mortality risk. Other important variables were plasma protein level, with a 10-g/dL decline resulting in a 4.2% increase in mortality risk; and hemoglobin, with a 1-g/dL decline resulting in a 2.9% increase in mortality risk. Most of the surviving lake sturgeon were unable to restore hemoglobin, hematocrit, and plasma protein to pre-attack levels by the end of the 2-week recovery period. We developed an index of histological spleen condition, which indicated that short-duration (< 5-d) sea lamprey attachments depleted red blood cell reserves faster than longer-duration attacks. Our study results indicate that sea lamprey parasitism has the potential to induce acute anemia in lake sturgeon and that nonlethal attacks on smaller (< 760-mm) fish can have serious physiological implications.     

Resistance to glyphosate in Lolium rigidum

Annual ryegrass (Lolium rigidum) is a widespread and important weed of Australia and populations of this weed have developed resistance to most major herbicides, including glyphosate. The possible mechanisms of resistance have been examined in one glyphosate-resistant Lolium population. No major differences were observed between resistant and susceptible biotypes in respect of (i) the target enzyme (EPSP synthase), (ii) DAHP synthase, the first enzyme of the target (shikimate) pathway, (iii) absorption of glyphosate, or (iv) translocation. Following treatment with glyphosate, there was greater accumulation of shikimate (derived from shikimate-3-Pi) in susceptible than in resistant plants. In addition, the resistant population exhibited cross-resistance to 2-hydroxy-3-(1,2,4-triazol-1-yl)propyl phosphonate, a herbicide which, although structurally similar to glyphosate, acts at an unrelated target site. On the basis of these observations we speculate that movement of glyphosate to its site of action in the plastid is involved in the resistance mechanism. © 1999 Society of Chemical Industry     

Differences in water-use efficiency among perennial forages used by the dairy industry under optimum and deficit irrigation

The cost and scarcity of water is placing increasing pressure on Australian dairy farmers to utilise water for forage production as efficiently as possible. This study aimed to identify perennial forage species with greater water-use efficiency (WUE) than the current dominant species, perennial ryegrass (Lolium perenne L.). Fifteen perennial forage species were investigated under optimum irrigation and two deficit irrigation treatments, over three years at Camden, NSW, on a brown Dermsol in a warm temperate climate. Under optimal irrigation, there was a nearly twofold difference in mean WUE_t (total yield/evapotranspiration) between forages, with kikuyu (Pennisetum clandestinum Hochst. ex. chiov.) having the highest (27.3 kg ha⁻¹ mm⁻¹) and birdsfoot trefoil (Lotus corniculatus L.) the lowest (14.8 kg ha⁻¹ mm⁻¹). Kikuyu was also the most water use efficient forage under the extreme deficit irrigation treatment, although its mean WUE_t declined by 15% to 23.2 kg ha⁻¹ mm⁻¹, while white clover (Trifolium repens L.) in the same treatment had the largest decline of 44% and the lowest WUE_t of only 8.8 kg ha⁻¹ mm⁻¹. In order to maximise WUE for any forage, it is necessary to maximise yield, as there is a strong positive relationship between yield and WUE_t.     

Evidence for extreme partitioning of copper into a magmatic vapor phase

The discovery of copper sulfides in carbon dioxide- and chlorine-bearing bubbles in phenocryst-hosted melt inclusions shows that copper resides in a vapor phase in some shallow magma chambers. Copper is several hundred times more concentrated in magmatic vapor than in coexisting pantellerite melt. The volatile behavior of copper should be considered when modeling the volcanogenic contribution of metals to the atmosphere and may be important in the formation of copper porphyry ore deposits.     

Identification of trout and salmon bloods by simple immunological technique and by electrofocusing patterns of red cell enzyme superoxide dismutase

Species identification of animal bloods is readily achieved by immunological tests. Differentiation among fish species on this basis is more difficult although considerable success has been achieved on the basis of both inter- and intra-specific differences in their serum proteins. This report describes a method for the identification of the different species of fish within the Salmonidae family and some coarse fish families on the basis of an immunological test and electrofocusing patterns of the enzyme superoxide dismutase from the red cell. The immunological technique relies on the development of a specific anti-trout (Salmonidae) serum which is used initially to differentiate the blood of a Salmonidae from other freshwater fish. Further discrimination, within the Salmonidae, is made on the basis of the different polymorphic forms of the enzyme superoxide dismutase separated in a pH 2.5 to 8 gradient. Using this technique, it is possible to differentiate among salmon, sea/brown trout, char, cheetah trout, and a number of varieties of rainbow trout.