Influence of industrial light pollution on the sea-finding behaviour of flatback turtle hatchlings

2014 ◽  
Vol 41 (5) ◽  
pp. 421 ◽  
Author(s):  
Ruth L. Kamrowski ◽  
Col Limpus ◽  
Kellie Pendoley ◽  
Mark Hamann
Keyword(s):  
Cloud Cover ◽  
Industrial Development ◽  
Large Scale ◽  
Marine Turtle ◽  
Artificial Light ◽  
Moon Phase ◽  
Light Levels ◽  
Combination Of Methods ◽  
Industrial Lighting ◽  
Nesting Beaches

Context Numerous studies show that artificial light disrupts the sea-finding ability of marine turtle hatchlings. Yet very little has been published regarding sea-finding for flatback turtles. Given the current industrialisation of Australia’s coastline, and the large potential for disruption posed by industrial light, this study is a timely investigation into sea-finding behaviour of flatback turtle hatchlings. Aims We investigate sea-finding by flatback turtle hatchlings in relation to ambient light present in areas of planned or ongoing industrial development, and evaluate the fan and arena-based methods that are frequently used for quantifying hatchling dispersion. Methods Using a combination of methods, we assessed the angular range and directional preference of sea-finding hatchlings at two key flatback turtle rookeries, Peak and Curtis Islands, during January–February 2012 and 2013, and at Curtis Island in January 2014. Relative light levels at each site were measured using an Optec SSP-3 stellar photometer, and moon phase, moon stage and cloud cover were also recorded. Key results We found no evidence of impaired hatchling orientation, and observed very low levels of light at Peak Island. However, at Curtis Island, hatchlings displayed reduced sea-finding ability, with light horizons from the direction of nearby industry significantly brighter than from other directions. The sea-finding disruption observed at Curtis Island was less pronounced in the presence of moonlight. Conclusions The reduced sea-finding ability of Curtis Island hatchlings was likely due to both altered light horizons from nearby industry, as well as beach topography. Both methods of assessing hatchling orientation have benefits and limitations. We suggest that fan-based methods, combined with strategically placed arenas, would provide the best data for accurately assessing hatchling sea-finding. Implications Sky glow produced by large-scale industrial development appears detrimental to sea-finding by flatback turtle hatchlings. As development continues around Australia’s coastline, we strongly recommend continued monitoring of lighting impacts at adjacent turtle nesting beaches. We also advise rigorous management of industrial lighting, which considers cumulative light levels in regions of multiple light producers, as well as moon phase, moon-stage, cloud cover and time of hatchling emergence. All these factors affect the likelihood of disrupted hatchling sea-finding behaviour at nesting beaches exposed to artificial light-glow, industrial or otherwise.

scholarly journals Assessing coastal artificial light and potential exposure of wildlife at a national scale: the case of marine turtles in Brazil

2020 ◽  
Vol 29 (4) ◽  
pp. 1135-1152 ◽  
Author(s):  
Liliana P. Colman ◽  
Paulo H. Lara ◽  
Jonathan Bennie ◽  
Annette C. Broderick ◽  
Juliana R. de Freitas ◽  
...  
Keyword(s):  
Nest Site Selection ◽  
Marine Turtle ◽  
Conservation Strategies ◽  
Brazilian Coast ◽  
Light Pollution ◽  
Artificial Light ◽  
Turtle Species ◽  
Marine Turtles ◽  
Light Levels ◽  
Nesting Beaches

AbstractCoastal areas provide critical nesting habitat for marine turtles. Understanding how artificial light might impact populations is key to guide management strategies. Here we assess the extent to which nesting populations of four marine turtle species—leatherback (Dermochelys coriacea), olive ridley (Lepidochelys olivacea), hawksbill (Eretmochelys imbricata) and two subpopulations of loggerhead (Caretta caretta) turtles—are exposed to light pollution across 604 km of the Brazilian coast. We used yearly night-time satellite images from two 5-year periods (1992–1996 and 2008–2012) from the US Air Force Defense Meteorological Satellite Programme (DMSP) to determine the proportion of nesting areas that are exposed to detectable levels of artificial light and identify how this has changed over time. Over the monitored time-frame, 63.7% of the nesting beaches experienced an increase in night light levels. Based on nest densities, we identified 54 reproductive hotspots: 62.9% were located in areas potentially exposed to light pollution. Light levels appeared to have a significant effect on nest densities of hawksbills and the northern loggerhead turtle stock, however high nest densities were also seen in lit areas. The status of all species/subpopulations has improved across the time period despite increased light levels. These findings suggest that (1) nest site selection is likely primarily determined by variables other than light and (2) conservation strategies in Brazil appear to have been successful in contributing to reducing impacts on nesting beaches. There is, however, the possibility that light also affects hatchlings in coastal waters, and impacts on population recruitment may take longer to fully manifest in nesting numbers. Recommendations are made to further this work to provide deeper insights into the impacts of anthropogenic light on marine turtles.

scholarly journals Large-scale deregulation of gene expression by artificial light at night in tadpoles of common toads

2021 ◽  
Author(s):  
Morgane Touzot ◽  
Tristan Lefebure ◽  
Thierry Lengagne ◽  
Jean Secondi ◽  
Adeline Dumet ◽  
...  
Keyword(s):  
Gene Expression ◽  
Large Scale ◽  
Bufo Bufo ◽  
Artificial Light ◽  
Light At Night ◽  
Light Levels ◽  
Immune Challenges ◽  
Physiological Pathways ◽  
Low Levels ◽  
Dose Dependent

Artificial light at night (ALAN) affects numerous physiological and behavioural mechanisms in various species by potentially disturbing circadian timekeeping systems. Although gene-specific approaches have already shown the deleterious effect of ALAN on the circadian clock, immunity and reproduction, large-scale transcriptomic approaches with ecologically relevant light levels are still lacking to assess the global impact of ALAN on biological processes. Moreover, studies have focused mainly on variations in gene expression during the night in the presence of ALAN but never during the day. In a controlled laboratory experiment, transcriptome sequencing of Bufo bufo tadpoles revealed that ALAN affected gene expression at both night and daytime with a dose-dependent effect and globally induced a downregulation of genes. ALAN effects were detected at very low levels of illuminance (0.1 lux) and affected mainly genes related to the innate immune system and, to a lesser extend to lipid metabolism. These results indicate that a broad range of physiological pathways is impacted at the molecular level by very low levels of ALAN potentially resulting in reduced survival under environmental immune challenges.

scholarly journals Cloud obstruction and snow cover in Alpine areas from MODIS products

2014 ◽  
Vol 18 (11) ◽  
pp. 4579-4600 ◽  
Author(s):  
P. Da Ronco ◽  
C. De Michele
Keyword(s):  
Snow Cover ◽  
River Basin ◽  
Cloud Cover ◽  
Large Scale ◽  
Snow Water Equivalent ◽  
Practical Interest ◽  
Computational Effort ◽  
Po River ◽  
Average Value ◽  
Po River Basin

Abstract. Snow cover maps provide information of great practical interest for hydrologic purposes: when combined with point values of snow water equivalent (SWE), they enable estimation of the regional snow resource. In this context, Earth observation satellites are an interesting tool for evaluating large scale snow distribution and extension. MODIS (MODerate resolution Imaging Spectroradiometer on board Terra and Aqua satellites) daily Snow Covered Area product has been widely tested and proved to be appropriate for hydrologic applications. However, within a daily map the presence of cloud cover can hide the ground, thus obstructing snow detection. Here, we consider MODIS binary products for daily snow mapping over the Po River basin. Ten years (2003–2012) of MOD10A1 and MYD10A1 snow maps have been analysed and processed with the support of a 500 m resolution Digital Elevation Model (DEM). We first investigate the issue of cloud obstruction, highlighting its dependence on altitude and season. Snow maps seem to suffer the influence of overcast conditions mainly in mountain and during the melting period. Thus, cloud cover highly influences those areas where snow detection is regarded with more interest. In spring, the average percentages of area lying beneath clouds are in the order of 70%, for altitudes over 1000 m a.s.l. Then, starting from previous studies, we propose a cloud removal procedure and we apply it to a wide area, characterized by high geomorphological heterogeneity such as the Po River basin. In conceiving the new procedure, our first target was to preserve the daily temporal resolution of the product. Regional snow and land lines were estimated for detecting snow cover dependence on elevation. In cases when there was not enough information on the same day within the cloud-free areas, we used temporal filters with the aim of reproducing the micro-cycles which characterize the transition altitudes, where snow does not stand continually over the entire winter. In the validation stage, the proposed procedure was compared against others, showing improvements in the performance for our case study. The accuracy is assessed by applying the procedure to clear-sky maps masked with additional cloud cover. The average value is higher than 95% considering 40 days chosen over all seasons. The procedure also has advantages in terms of input data and computational effort requirements.

scholarly journals Geographical Change of the Japanese National Land in the 200 Years Using INŌ’s Map with GIS

2019 ◽  
Vol 1 ◽  
pp. 1-2
Author(s):  
Yuji Murayama ◽  
Yuki Iwai
Keyword(s):  
Political System ◽  
Industrial Development ◽  
Large Scale ◽  
Geographic Information ◽  
Point Of View ◽  
The Political ◽  
Spatial Transformation ◽  
Survey Line ◽  
The Difference ◽  
The 19Th Century

<p><strong>Abstract.</strong> This presentation discusses the regional changes quantitatively in the 200 years through the overlay analysis of the present map and the INŌ’s map made by Tadataka INO in 1821 (Figure 1). INO surveyed the coastline and major roads on foot. He investigated not only survey lines, but also various geographic information such as rivers, lakes, mountains, village names, castles, temples, administrative boundaries, etc. Visualizing all of the 214 sheets of the INŌ’s large-scale map with Geographic Information Systems (GIS), we can analyse the national land condition seamlessly at the end of the Edo era.</p><p>Methodological point of view, we have serious problems including the scale, projection, identification of geographic features and so on, when we compare the old map with the present. In this connection, digitalizing the INŌ’s map as the GIS data is very useful to examine the spatial transformation scientifically during the 200 years. The digital INŌ’s map was constructed by employing the geo-reference function of GIS with the triangulation method. The survey line was converted into the line feature of vector data, and the place names were converted into the point feature of raster data. The distance of the survey line was measured by GIS-based geometric operation.</p><p>We obtained the following findings. The distributions of villages, ports, and facilities in western Japan were denser than those in eastern Japan in the 19th century. This was caused not only by the difference in natural environment and landform but also by socioeconomic factors including the locations of the castle towns and industrial activities. The regional structure has been dramatically transformed by the modernization of the political system, transportation system, and industrial development in reclaimed areas (Figure 2). It is concluded that most parts of changes in regional characteristics have been attained by overcoming the natural constraints. However, the difference in the political system has also been influential to the formation of the present regional system.</p>

scholarly journals Capitalismo distrettuale, localismi d'impresa, globalizzazione

2008 ◽  
Keyword(s):  
Industrial Development ◽  
Large Scale ◽  
International Markets ◽  
Scope Economies ◽  
North East ◽  
The North ◽  
Productive System ◽  
Dimensional Growth ◽  
It Revolution ◽  
Made In

From the late Sixties on, industrial development in Italy evolved through the spread of small and medium sized firms, aggregated in district networks, with an elevated propensity to enterprise and the marked presence of owner-families. Installed within the local systems, the industrial districts tended to simulate large-scale industry exploiting lower costs generated by factors that were not only economic. The districts are characterised in terms of territorial location (above all the thriving areas of the North-east and Centre) and sector, since they are concentrated in the "4 As" (clothing-fashion, home-decor, agri-foodstuffs, automation-mechanics), with some overlapping with "Made in Italy". How can this model be assessed? This is the crucial question in the debate on the condition and prospects of the Italian productive system between the supporters of its capacity to adapt and the critics of economic dwarfism. A dispassionate judgement suggests that the prospects of "small is beautiful" have been superseded, but that the "declinist" view, that sees only the dangers of globalisation and the IT revolution for our SMEs is risky. The concept of irreversible crisis that prevails at present is limiting, both because it is not easy either to "invent", or to copy, a model of industrialisation, and because there is space for a strategic repositioning of the district enterprises. The book develops considerations in this direction, showing how an evolution of the district model is possible, focusing on: gains in productivity, scope economies (through diversification and expansion of the range of products), flexibility of organisation, capacity to meld tradition and innovation aiming at product quality, dimensional growth of the enterprises, new forms of financing, active presence on the international markets and valorisation of the resources of the territory. It is hence necessary to reactivate the behavioural functions of the entrepreneurs.

scholarly journals REFLECTANCE RECONSTRUCTION OF HYPERSPECTRAL IMAGE BASED ON GAUSSIAN SURFACE FITTING

2020 ◽  
Vol XLIII-B3-2020 ◽  
pp. 1365-1369
Author(s):  
S. Lyu ◽  
C. Huang ◽  
M. Hou
Keyword(s):  
Light Source ◽  
Large Scale ◽  
Diffuse Reflectance ◽  
Hyperspectral Image ◽  
Surface Fitting ◽  
Artificial Light ◽  
Hyperspectral Reflectance ◽  
Reconstruction Accuracy ◽  
Artificial Light Source ◽  
Gaussian Surface

Abstract. Different from the field of remote sensing, artificial lights are often utilized as the energy source for spectral imaging in the ground hyperspectral applications. The kind of double-spot light source is widely adopted in some large scale ground hyperspectral applications. However, it is hard to reach a satisfied lighting without difference in light intensity in many cases although the lamps are tuned carefully. Therefore, a reflectance calibration of hyperspectral imaging based on the data of diffuse reflectance standard and Gaussian surface fitting is proposed in this paper. The purpose is to improve the reconstruction accuracy of hyperspectral reflectance image by minimized the error caused by the uneven illumination of artificial light source. The method has a higher accuracy than traditional one according to the experiment results.

scholarly journals Does behaviour affect the dispersal of flatback post-hatchlings in the Great Barrier Reef?

2017 ◽  
Vol 4 (5) ◽  
pp. 170164 ◽  
Author(s):  
Natalie Wildermann ◽  
Kay Critchell ◽  
Mariana M. P. B. Fuentes ◽  
Colin J. Limpus ◽  
Eric Wolanski ◽  
...  
Keyword(s):  
Great Barrier Reef ◽  
Early Life ◽  
Marine Turtle ◽  
Life Stages ◽  
Barrier Reef ◽  
Early Life Stages ◽  
Turtle Species ◽  
Local Water ◽  
Natator Depressus ◽  
Nesting Beaches

The ability of individuals to actively control their movements, especially during the early life stages, can significantly influence the distribution of their population. Most marine turtle species develop oceanic foraging habitats during different life stages. However, flatback turtles ( Natator depressus ) are endemic to Australia and are the only marine turtle species with an exclusive neritic development. To explain the lack of oceanic dispersal of this species, we predicted the dispersal of post-hatchlings in the Great Barrier Reef (GBR), Australia, using oceanographic advection-dispersal models. We included directional swimming in our models and calibrated them against the observed distribution of post-hatchling and adult turtles. We simulated the dispersal of green and loggerhead turtles since they also breed in the same region. Our study suggests that the neritic distribution of flatback post-hatchlings is favoured by the inshore distribution of nesting beaches, the local water circulation and directional swimming during their early dispersal. This combination of factors is important because, under the conditions tested, if flatback post-hatchlings were entirely passively transported, they would be advected into oceanic habitats after 40 days. Our results reinforce the importance of oceanography and directional swimming in the early life stages and their influence on the distribution of a marine turtle species.

Corporate Structure, Industrial Development, and Structural Change in South Africa

2021 ◽  
pp. 348-374
Author(s):  
Pamela Mondliwa ◽  
Simon Roberts
Keyword(s):  
South Africa ◽  
South African ◽  
Industrial Development ◽  
Large Scale ◽  
Economies Of Scale ◽  
Corporate Structure ◽  
Continuity And Change ◽  
Economic Concentration ◽  
And Control

The orientation of large corporations is at the heart of how countries develop. These firms make large-scale investments and realize economies of scale and scope, as well as make long-term commitments to the learning and research necessary to build capabilities required for industrial development. In many industries and sectors the large firms have key technologies, govern access to markets, and control material inputs which can shape the structure of an economy. The chapter reviews the changing corporate structure in South Africa focusing on the implications for industrial development, the evolving internationalization of South African businesses, and the political economy of economic policy. While the South African economy has remained highly concentrated, the corporate structure has altered in fundamental ways. The chapter identifies key elements of continuity and change to explain the implications of the continued high levels of economic concentration for the economy through the lens of the corporate structure.

scholarly journals Synoptic-scale controls of fog and low-cloud variability in the Namib Desert

2020 ◽  
Vol 20 (6) ◽  
pp. 3415-3438 ◽  
Author(s):  
Hendrik Andersen ◽  
Jan Cermak ◽  
Julia Fuchs ◽  
Peter Knippertz ◽  
Marco Gaetani ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Cloud Cover ◽  
Large Scale ◽  
Marine Boundary Layer ◽  
Synoptic Scale ◽  
Namib Desert ◽  
Data Set ◽  
Air Masses ◽  
Low Cloud ◽  
Low Cloud Cover

Abstract. Fog is a defining characteristic of the climate of the Namib Desert, and its water and nutrient input are important for local ecosystems. In part due to sparse observation data, the local mechanisms that lead to fog occurrence in the Namib are not yet fully understood, and to date, potential synoptic-scale controls have not been investigated. In this study, a recently established 14-year data set of satellite observations of fog and low clouds in the central Namib is analyzed in conjunction with reanalysis data in order to identify synoptic-scale patterns associated with fog and low-cloud variability in the central Namib during two seasons with different spatial fog occurrence patterns. It is found that during both seasons, mean sea level pressure and geopotential height at 500 hPa differ markedly between fog/low-cloud and clear days, with patterns indicating the presence of synoptic-scale disturbances on fog and low-cloud days. These regularly occurring disturbances increase the probability of fog and low-cloud occurrence in the central Namib in two main ways: (1) an anomalously dry free troposphere in the coastal region of the Namib leads to stronger longwave cooling of the marine boundary layer, increasing low-cloud cover, especially over the ocean where the anomaly is strongest; (2) local wind systems are modulated, leading to an onshore anomaly of marine boundary-layer air masses. This is consistent with air mass back trajectories and a principal component analysis of spatial wind patterns that point to advected marine boundary-layer air masses on fog and low-cloud days, whereas subsiding continental air masses dominate on clear days. Large-scale free-tropospheric moisture transport into southern Africa seems to be a key factor modulating the onshore advection of marine boundary-layer air masses during April, May, and June, as the associated increase in greenhouse gas warming and thus surface heating are observed to contribute to a continental heat low anomaly. A statistical model is trained to discriminate between fog/low-cloud and clear days based on information on large-scale dynamics. The model accurately predicts fog and low-cloud days, illustrating the importance of large-scale pressure modulation and advective processes. It can be concluded that regional fog in the Namib is predominantly of an advective nature and that fog and low-cloud cover is effectively maintained by increased cloud-top radiative cooling. Seasonally different manifestations of synoptic-scale disturbances act to modify its day-to-day variability and the balance of mechanisms leading to its formation and maintenance. The results are the basis for a new conceptual model of the synoptic-scale mechanisms that control fog and low-cloud variability in the Namib Desert and will guide future studies of coastal fog regimes.

scholarly journals A Global Analysis of Anthropogenic Development of Marine Turtle Nesting Beaches

2020 ◽  
Vol 12 (9) ◽  
pp. 1492
Author(s):  
Sarah J. Biddiscombe ◽  
Elliott A. Smith ◽  
Lucy A. Hawkes
Keyword(s):  
Global Analysis ◽  
Earth Satellite ◽  
Google Earth ◽  
Coastal Development ◽  
Marine Turtle ◽  
Intergovernmental Panel ◽  
Sea Levels ◽  
Marine Turtles ◽  
Coastal Squeeze ◽  
Nesting Beaches

The Intergovernmental Panel on Climate Change predicts that sea levels will rise by up to 0.82 m in the next 100 years. In natural systems, coastlines would migrate landwards, but because most of the world’s human population occupies the coast, anthropogenic structures (such as sea walls or buildings) have been constructed to defend the shore and prevent loss of property. This can result in a net reduction in beach area, a phenomenon known as “coastal squeeze”, which will reduce beach availability for species such as marine turtles. As of yet, no global assessment of potential future coastal squeeze risk at marine turtle nesting beaches has been conducted. We used Google Earth satellite imagery to enumerate the proportion of beaches over the global nesting range of marine turtles that are backed by hard anthropogenic coastal development (HACD). Mediterranean and North American nesting beaches had the most HACD, while the Australian and African beaches had the least. Loggerhead and Kemp’s ridley turtle nesting beaches had the most HACD, and flatback and green turtles the least. Future management approaches should prioritise the conservation of beaches with low HACD to mitigate future coastal squeeze.

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