CONVERGENCE OF THE G-7: A COINTEGRATION APPROACH

Income convergence among the G-7 countries was demonstrated using Theil's inequality (entropy) index. G-7 convergence was also found for three potential factors of influence on economic growth: government expenditure, investment expenditure, and industrial employment. Pairwise cointegration tests indicated that income inequality was cointegrated with the other three inequality measures for the time period of 1950-88. Finally, Johansen's I(2) multi-cointegration tests indicated that three of the four inequality measures (i.e. income, investment expenditure, and industrial employment) were cointegrated suggesting that there exists a long-run equilibrium between the inequality in income, investment expenditure, and industrial employment.Agricultural and Food Policy,

Heated aquatic microcosms for climate change experiments

Ponds and shallow lakes are likely to be strongly affected by climate change, and by increase in environmental temperature in particular. Hydrological regimes and nutrient cycling may be altered, plant and animal communities may undergo changes in both composition and dynamics, and long-term and difficult to reverse switches between alternative stable equilibria may occur. A thorough understanding of the potential effects of increased temperature on ponds and shallow lakes is desirable because these ecosystems are of immense importance throughout the world as sources of drinking water, and for their amenity and conservation value. This understanding can only come through experimental studies in which the effects of different temperature regimes are compared. This paper reports design details and operating characteristics of a recently constructed experimental facility consisting of 48 aquatic microcosms which mimic the pond and shallow lake environment. Thirty-two of the microcosms can be heated and regulated to simulate climate change scenarios, including those predicted for the UK. The authors also summarise the current and future experimental uses of the microcosms

Shining new light on mammalian diving physiology using wearable near-infrared spectroscopy

Investigation of marine mammal dive-by-dive blood distribution and oxygenation has been limited by a lack of non-invasive technology for use in freely diving animals. Here, we developed a non-invasive near-infrared spectroscopy (NIRS) device to measure relative changes in blood volume and haemoglobin oxygenation continuously in the blubber and brain of voluntarily diving harbour seals. Our results show that seals routinely exhibit preparatory peripheral vasoconstriction accompanied by increased cerebral blood volume approximately 15 s before submersion. These anticipatory adjustments confirm that blood redistribution in seals is under some degree of cognitive control that precedes the mammalian dive response. Seals also routinely increase cerebral oxygenation at a consistent time during each dive, despite a lack of access to ambient air. We suggest that this frequent and reproducible reoxygenation pattern, without access to ambient air, is underpinned by previously unrecognised changes in cerebral drainage. The ability to track blood volume and oxygenation in different tissues using NIRS will facilitate a more accurate understanding of physiological plasticity in diving animals in an increasingly disturbed and exploited environment

Dynamic habitat corridors for marine mammals: intensive use of a coastal channel by harbour seals is modulated by tidal currents [abstract]

Dynamic habitat corridors for marine mammals: intensive use of a coastal channel by harbour seals is modulated by tidal currents [abstract

Increased metabolic rate of hauled-out harbor seals (Phoca vitulina) during the molt

Harbor seals (Phoca vitulina) live in cold temperate or polar seas and molt annually, renewing their fur over a period of approximately four weeks. Epidermal processes at this time require a warm skin and therefore to avoid an excessive energy cost at sea during the molt, harbour seals and many other pinnipeds increase the proportion of time hauled out on land. We predicted that metabolic rate during haulout would be greater during the molt to sustain an elevated skin temperature in order to optimize skin and hair growth. To examine this, we measured post-haulout oxygen consumption (V̇O2) in captive harbor seals during molt and post-molt periods. We recorded greater V̇O2 of seals while molting than when the molt was complete. Post-haulout V̇O2 increased faster and reached a greater maximum at 40 minutes during the molt. Thereafter, V̇O2 decreased but still remained greater suggesting that while metabolic rate was relatively high throughout haulouts, it was most pronounced in the first 40 minutes. Air temperature, estimated heat increment of feeding (eHIF) and mass also explained 15.5% of V̇O2 variation over 180 minutes post-haulout, suggesting that the environment, feeding state and body size influenced the metabolic rate of individual animals. These results show that moulting seals have greater metabolic rates when hauled out, especially during the early stages of the haulout period. As a consequence, human disturbance that changes the haulout behaviour of molting seals will increase their energy costs and potentially extend the duration of the molt

Type-II micro-comb generation in a filter-driven four wave mixing laser [Invited]

We experimentally demonstrate the generation of highly coherent Type-II micro-combs based on a microresonator nested in a fiber cavity loop, known as the filter-driven four wave mixing (FD-FWM) laser scheme. In this system, the frequency spacing of the comb can be adjusted to integer multiples of the free-spectral range (FSR) of the nested micro-resonator by properly tuning the fiber cavity length. Sub-comb lines with single FSR spacing around the primary comb lines can be generated. Such a spectral emission is known as a “Type-II comb.” Our system achieves a fully coherent output. This behavior is verified by numerical simulations. This study represents an important step forward in controlling and manipulating the dynamics of an FD-FWM laser

Sympatric seals, satellite tracking and protected areas : habitat-based distribution estimates for conservation and management

Analysis was funded by the UK Government Department for Business, Energy and Industrial Strategy (BEIS; OESEA-16-76/OESEA-17-78) with support from the Natural Environment Research Council (NERC; INSITE Phase II NE/T010614/1 EcoSTAR), EU INTERREG (MarPAMM), and the Scottish Government (MMSS/002/15). DJFR’s contribution was funded by NERC National Capability Funding (NE/R015007/1). WJG was supported by INSITE Phase I (MAPS). Telemetry tags and their deployment were funded in the UK by BEIS (and previous incarnations), NERC, Marine Scotland, Scottish Government, NatureScot, SMRU, SMRU Instrumentation Group, Marine Current Turbines, Ørsted, the Met Office, the Zoological Society of London (ZSL), the Crown Estate, Highlands & Islands Enterprise, Moray Firth Renewables Limited (MORL), Beatrice Offshore Windfarm Limited (BOWL), SITA Trust, BBC Wildlife Fund and the Hampshire & Isle of Wight Wildlife Trust. Tags and their deployment in Ireland were funded by Inland Fisheries Ireland, the Department of Communications, Marine and Natural Resources, the Higher Education Authority of Ireland, the National Geographic Society, the Department of Agriculture, Food and the Marine, and the National Parks and Wildlife Service. UK aerial surveys conducted by SMRU were funded by NERC (NE/R015007/1), NatureScot, the Department for Agriculture, Environment and Rural Affairs (Northern Ireland), Marine Current Turbines, Marine Scotland, Natural England, and Scottish Power. Aerial surveys in Ireland were funded by the Department for Tourism, Culture, Arts, Gaeltacht, Sport and Media.Marine predator populations are crucial to the structure and functioning of ecosystems. Like many predator taxa, pinnipeds face an increasingly complex array of natural and anthropogenic threats. Understanding the relationship between at-sea processes and trends in abundance at land-based monitoring sites requires robust estimates of at-sea distribution, often on multi-region scales. Such an understanding is critical for effective conservation management, but estimates are often limited in spatial extent by spatial coverage of animal-borne tracking data. Grey (Halichoerus grypus) and harbour seals (Phoca vitulina) are sympatric predators in North Atlantic shelf seas. The United Kingdom (UK) and Ireland represents an important population centre for both species, and Special Areas of Conservation (SACs) are designated for their monitoring and protection. Here we use an extensive high-resolution GPS tracking dataset, unprecedented in both size (114 grey and 239 harbour seals) and spatial coverage, to model habitat preference and generate at-sea distribution estimates for the entire UK and Ireland populations of both species. We found regional differences in environmental drivers of distribution for both species which likely relate to regional variation in diet and population trends. Moreover, we provide SAC-specific estimates of at-sea distribution for use in marine spatial planning, demonstrating that hotspots of at-sea density in UK and Ireland-wide maps cannot always be apportioned to the nearest SAC. We show that for grey seals, colonial capital breeders, there is a mismatch between SACs (where impacts are likely to be detected) and areas where impacts are most likely to occur (at sea). We highlight an urgent need for further research to elucidate the links between at-sea distribution during the foraging season and population trends observed in SACs. More generally, we highlight that the potential for such a disconnect needs to be considered when designating and managing protected sites, particularly for species that aggregate to breed and exhibit partial migration (e.g. grey seals), or spatial variation in migration strategies. We demonstrate the use of strategic tracking efforts to predict distribution across multiple regions, but caution that such efforts should be mindful of the potential for differences in species-environment relationships despite similar accessible habitats.Publisher PDFPeer reviewe

Heated aquatic microcosms for climate change experiments

We are experiencing global climate change (e.g. Houghton et al. 1996; Huanget al. 2000). One of the main features of this change is a significant andcontinuing rise in temperature, attributable at least in part to anthropogenicenhancement of the greenhouse effect (Kerr 2000). The projected magnitudeand rapidity of this phenomenon is cause for major concern about how thebiosphere will respond