Transatlantic migration by post-breeding puffins: a strategy to exploit a temporarily abundant food resource?

The distribution of Atlantic puffins (Fratercula arctica) from Skellig Michael, south-west Ireland, was investigated using geolocation loggers between the 2010 and 2011 breeding seasons. All tracked birds travelled rapidly west into the North Atlantic at the end of the breeding season in August, with the majority undertaking transatlantic trips from Ireland to the Newfoundland-Labrador shelf. The furthest distance from the colony reached by each bird was not influenced by body mass or sex and was achieved in approximately 20 days. By October, all birds had moved back to the mid Atlantic where they remained resident until returning to the breeding colony. The most parsimonious explanation for the rapid, directed long-distance migration is that birds exploit the seasonally high abundance of prey [e.g., fish species such as capelin (Mallotus villosus) and sandlance (Ammodytes spp.)] off the Canadian coast, which is also utilised by large populations of North American seabirds at this time. Once the availability of this short-term prey resource has diminished, the tracked puffins moved back towards the north-east Atlantic. A relationship between relative abundance of puffins and zooplankton was found in all winter months, but after correcting for spatial autocorrelation, was only significant in November and January. Nevertheless, these results suggest a potential switch in diet from mainly fish during the breeding and early post-breeding periods to zooplankton over the remaining winter period. This study suggests that puffins from south-west Ireland have a long-distance migration strategy that is rare in breeding puffins from the UK and identifies a key non-breeding destination for puffins from Ireland. This has implications for the susceptibility of different breeding populations to the effects of possible climatic or oceanographic change.     

Photocatalytic formation of hydrogen peroxide over highly porous illuminated ZnO and TiO2thin film

The photocatalytic formation of hydrogen peroxide over ZnO and TiO₂thin films has been investigated in aqueous phase in the presence of molecular oxygen as an electron acceptor. These films are highly porous and showed enhanced catalytic activity in the photochemical formation of hydrogen peroxide. The amount of H₂O₂formed during 2 hour light illumination is 4–6 μM and the rates of formation of hydrogen peroxide of both the films are almost comparable. The yield of hydrogen peroxide increases with the increase in irradiation time and a trend of steady state concentration of H₂O₂is observed in the case of TiO₂thin film. Photodissolution of ZnO particles is observed in some extent during the process of prolonged UV light illumination.     

Diurnal migration and vertical distribution of phyllosoma larvae of the western rock lobster Panulirus cygnus

Studies off the west coast of Australia showed that the phyllosoma larvae of Panulirus cygnus George undergo a diurnal vertical migration, with light as an important factor influencing the depth distribution of all 9 phyllosoma stages. The early stages (I to III) occurred at the surface at night regardless of moonlight intensity, whereas late stages (VI to IX) concentrated at the surface only on nights with less than 5% of full moonlight. Midday peak densities of early-stage larvae occurred in the 30 to 60 m depth range while those of mid (IV to VI) and late stages were in the 50 to 120 m range. Depths of peak densities of larvae increased with distance offshore. The limits of vertical distribution of the phyllosoma remained within ranges of illuminance which were estimated to be in the order of 50 to 250 E m^-2 sec^-1 for early stages, 20 to 200 E m^-2 sec^-1 for mid stages and 5 to 50 E m^-2 sec^-1 for late stages. Minimal rates of net vertical movement were estimated for the larvae. Early stages exhibited mean net rates of ascent and descent of 13.7 and 13.0 m h^-1, respectively, while the rates for mid stages were 16.0 and 16.6 m h^-1 and for late stages 19.4 and 20.1 m h^-1. Diurnal migrations and vertical distribution are shown to have a vital role in the relationships between circulation in the south-eastern Indian Ocean and the transport and dispersal of the phyllosoma larvae. The diurnal migrations of early stages place them at the surface at night, when offshore vectors of wind-driven ocean-surface transport dominate, and below the depth of wind-induced transport during the day, when offshore vectors are small or negative, thus accounting for their offshore displacement. Mid and late stages, because of their deeper daytime distribution and absence from the surface on moonlight nights, are predominantly subject to circulation features underlying the immediate surface layer. This is hypothesized to account for the return of the phyllosoma to areas near the continental shelf edge by subjecting them to a coastward mass transport of water which underlies the immediate surface layer.The western rock lobster is referred to as P. longipes or P. longipes cygnus in some of the literature quoted; these are synonymous with P. cygnus.     

Effect of combined application of methyl isothiocyanate and chloropicrin on their transformation

Combining several soil fumigants to increase the broad spectrum of pest control is a common fumigation practice in current production agriculture. In this study, we investigated the effect of combined application of chloropicrin and methyl isothiocyanate (MITC) on their transformations and persistence in the environment. In aqueous solution, no direct reaction between MITC and chloropicrin occurred and relatively slow rates of hydrolysis of these compounds were observed in aquatic environments free of suspended solids. The transformation of chloropicrin, however, was accelerated in aqueous solution with MITC because of a reduction reaction with bisulfide (HS(-)), which is a by-product of MITC hydrolysis. In soil, when fumigants were applied simultaneously, the degradation of MITC was suppressed under the bi-fumigant application due to the inhibition of soil microbial activity and a possible abiotic competition with chloropicrin for a limited number of reaction sites on the surface of soil particles. However, the degradation rate of chloropicrin was significantly enhanced in the bi-fumigant soil system, which was primarily attributed to the reaction of chloropicrin and HS(-). Two sequential application approaches were developed to investigate the feasibility of the combined application of metam sodium (parent compound of MITC) and chloropicrin in soil and assess their potential effects on environmental fate. For both application sequences, the degradation of chloropicrin was accelerated and that of MITC, as a major breakdown product of metam sodium, was inhibited in soil.     

The costs and benefits of radon remediation programmes in existing homes: case study of action level selection

Radon gas can be present within buildings at sufficiently high levels that it becomes a health risk. Such levels can be reduced, and so radon remediation programmes in the home in UK Affected Areas should result in reduced risks to the population. This paper considers the benefits and costs of the domestic radon remediation programme in Northamptonshire, UK, and considers the implications of the choice of Action Level, in view of the adoption of different levels in many countries. A programme with a higher Action Level will cost less, and target those most at risk, but will be less cost effective. In addition, a higher Action Level leaves a higher residual dose and risk to the remaining population. Such doses are higher than and inconsistent with the radiation dose limits for the general public in the EU Basic Standards Directive.     

A critical comparison of the cost-effectiveness of domestic radon remediation programmes in three counties of England

Radon remediation programmes in domestic dwellings were carried out in five areas, from three counties of England, and the total costs obtained. A single company, which abided by the Code of Practice of the Radon Council of Great Britain, carried out the remediation. The dose savings from the programmes were calculated and used to estimate the number of lung cancers averted. The data obtained allowed the cost-effectiveness of the remediation programmes in each area to be calculated. The remediation programmes in three areas (Northants 2, 3 and North Oxfordshire) were cost-effective whereas those in two areas (Northants 1 and North Somerset) were not. To be cost-effective, the Northants I and North Somerset areas would need to increase the number of householders that carried out remediation, if they were over the UK Action Level. Health policy makers should concentrate their resources on communities in areas where there is a significant proportion of dwellings above the UK Action Level and where the number of properties being remediated is low.     

Consistency of implications of three role stressors across four countries

Relationships between role stressors (ambiguity, overload, and conflict), anxiety, commitment (affective and continuance), and turnover intention were examined. These variables were measured via a survey of 1396 nurses in a total of 15 hospitals in Hungary, Italy, the United Kingdom, and the United States. Three role stressors were expected to predict anxiety and indirectly predict intention to leave. Anxiety was expected to predict affective and continuance commitment, and anxiety, affective commitment, and continuance commitment were expected to predict intention to leave the hospital. Although mean score differences were expected across countries, direction of the relationships between variables were expected to be the same, which would indicate consistency regarding the implications of three role stressors across countries. AMOS's structural equations modeling program was used to test a multi‐group manifest variable path analysis. Results yielded support for the proposed relationships (NFI = 0.93; TLI = 0.89). It was tentatively concluded that stress is a culture‐general process. Copyright © 2005 John Wiley & Sons, Ltd.     

The effect of habit as a behavioural response in risk reduction programmes

A company's decision to implement a risk reduction programme must take account of employees' behavioural responses to the target risk. Hazard reporting by train drivers is examined in semi-structured interviews and a questionnaire study. It is suggested that the behavioural response of drivers, in terms of writing a report, depends on how the hazard is perceived. The response to “trivial” and “routine” hazards is habitual non-reporting, being characterized by a lack of risk evaluation. However, hazards that are evaluated as posing a significant risk are reported. Possible ways of breaking habitual responses to hazards, using behavioural change programmes, are discussed, and it is argued that management commitment is essential for their success.