Summer survey of dugong distribution and abundance in Shark Bay reveals additional key habitat area

2006 ◽  
Vol 33 (3) ◽  
pp. 243 ◽  
Author(s):  
David K. Holley ◽  
Ivan R. Lawler ◽  
Nicholas J. Gales
Keyword(s):  
Large Scale ◽  
Aerial Survey ◽  
Seasonal Migration ◽  
Population Estimate ◽  
Entire Region ◽  
Shark Bay ◽  
The North ◽  
Exmouth Gulf ◽  
First Time ◽  
Summer Survey

The first standardised summer aerial survey of dugongs within Shark Bay in Western Australia, and the fourth in a series of surveys of this area, was undertaken during February 2002. This survey returned a population estimate of 11 021 ± 1357 (s.e.), a result similar to the first two winter surveys in 1989 and 1994 but considerably lower than the 1999 survey. Distribution was markedly different in this survey compared with all previous surveys, which were conducted during winter, confirming that dugongs within Shark Bay undertake a seasonal migration driven by changes in sea surface temperature. In addition to this distribution pattern it was identified that 24% of the population during summer occurred within an area known as Henri Freycinet Harbour. That is, while dugongs have been reported in this south-western region of the bay previously in summer, this is the first time that the substantial size (2629 ± 780, s.e.) of the summer dugong population has been quantified. Differences in the population estimate between the 1999 survey and this survey may be explained through large-scale movement patterns of dugongs between Shark Bay and Ningaloo Reef and Exmouth Gulf to the north, patterns that should be considered in the management of dugongs for the entire region.

Offshore Claims and Problems in the North Sea

1965 ◽  
Vol 59 (3) ◽  
pp. 505-522 ◽  
Author(s):  
Richard Young
Keyword(s):  
North Sea ◽  
Large Scale ◽  
Geneva Convention ◽  
Legal Principles ◽  
The North ◽  
Legal Problems ◽  
The North Sea ◽  
The Subject ◽  
First Time ◽  
Economic Considerations

The possible presence of very large petroleum and natural gas reserves in the area beneath the North Sea is currently the subject of intense investigation. If confirmed, as seems likely in at least some localities, this occurrence will raise legal problems of considerable interest and complexity. For the North Sea is not merely an oilfield covered by water: for centuries it has been one of the world's major fishery regions and the avenue to and from the world's busiest seaports. Thus all three of the present principal uses of the sea—fishing, navigation, and the exploitation of submarine resources—promise to meet for the first time on a large scale in an area where all are of major importance. The process of reconciling the various interests at stake will provide the first thoroughgoing test of the adequacy and acceptability of the general principles laid down in the 1958 Geneva Convention on the Continental Shelf and should add greatly to the practice and precedents available in this developing branch of the law. In the present article an attempt is made to review some of the geographical and economic considerations involved in the North Sea situation, to note some of the technical and legal developments that have already taken place, and to consider these elements in the light of the various interests and legal principles concerned.

Change in abundance of dugongs in Shark Bay, Ningaloo and Exmouth Gulf, Western Australia: evidence for large-scale migration

2004 ◽  
Vol 31 (3) ◽  
pp. 283 ◽  
Author(s):  
Nick Gales ◽  
Robert D. McCauley ◽  
Janet Lanyon ◽  
Dave Holley
Keyword(s):  
Marine Protected Areas ◽  
Large Scale ◽  
Population Demographics ◽  
Shark Bay ◽  
Ningaloo Reef ◽  
Aerial Surveys ◽  
Large Numbers ◽  
Plausible Hypothesis ◽  
Exmouth Gulf ◽  
Regional Abundance

The third in a series of five-yearly aerial surveys for dugongs in Shark Bay, Ningaloo Reef and Exmouth Gulf was conducted in July 1999. The first two surveys provided evidence of an apparently stable population of dugongs, with ~1000 animals in each of Exmouth Gulf and Ningaloo Reef, and 10 000 in Shark Bay. We report estimates of less than 200 for each of Exmouth Gulf and Ningaloo Reef and ~14 000 for Shark Bay. This is an apparent overall increase in the dugong population over this whole region, but with a distributional shift of animals to the south. The most plausible hypothesis to account for a large component of this apparent population shift is that animals in Exmouth Gulf and Ningaloo Reef moved to Shark Bay, most likely after Tropical Cyclone Vance impacted available dugong forage in the northern habitat. Bias associated with survey estimate methodology, and normal changes in population demographics may also have contributed to the change. The movement of large numbers of dugongs over the scale we suggest has important management implications. First, such habitat-driven shifts in regional abundance will need to be incorporated in assessing the effectiveness of marine protected areas that aim to protect dugongs and their habitat. Second, in circumstances where aerial surveys are used to estimate relative trends in abundance of dugongs, animal movements of the type we propose could lead to errors in interpretation.

Evidence of 8.2-ka event in Southeast Asia inferred from marginal marine sediments off Kallang River Basin, Singapore

2021 ◽  
Author(s):  
Yama Dixit ◽  
Stephen Chua ◽  
Yu Ting Yan ◽  
Adam Switzer
Keyword(s):  
River Basin ◽  
Marine Sediments ◽  
Large Scale ◽  
Southern Oscillation ◽  
Signal Propagation ◽  
Warm Pool ◽  
Seasonal Migration ◽  
Monsoon Circulation ◽  
Tropical Regions ◽  
The North

<p>The Maritime Continent (MC) is located within the Indo-Pacific Warm Pool, which is known as the largest area of warm sea surface temperatures with the highest rainfall on Earth that drives the global atmospheric and hydrologic circulation. The complex climatic system of the MC is controlled by large-scale phenomena such as the seasonal migration of the Intertropical Convergence Zone which causes the northwest and southeast monsoon circulation in the region as well as tropical Indo-Pacific climate phenomena, the Indian Ocean Dipole in the west and the El Niño-Southern Oscillation operating to the east of the MC. In addition to interactions of these climate phenomena, their influence varies across the region due to island topography and ocean–atmosphere fluxes. Despite dedicated efforts, a comprehensive picture of the impacts of abrupt climate events such as the ‘8.2 ka event’ during the Holocene on the MC has proved elusive. Here we use sedimentology and stable isotopes of benthic foraminifera collected from the marginal marine sediments off the Kallang River Basin, Singapore to reconstruct paleoenvironmental history of the early-mid Holocene. Owing to the high sedimentation rate (~4.4 mm/yr), the timing and nature of the ‘8.2 ka event’ was examined in detail in this region making this an invaluable and unique archive to study up to sub-centennial changes. Comparison of the Kallang record with other high-resolution marine and absolutely dated terrestrial archives speleothems revealed that the timing of the onset of ‘8.2 ka event’ in the western IPWP region lags the cooling in the North Atlantic and that of Asian and Indian monsoon failure, by ~100years possibly implying a north-south signal propagation. The termination of the ‘8.2 ka event’, however may have occurred near synchronously between high and low tropical regions at ~7.96ka BP possibly linked via both atmospheric and oceanic processes.</p><p> </p>

scholarly journals Dusky sharks (Carcharhinus obscurus) undertake large-scale migrations between tropical and temperate ecosystems

2018 ◽  
Vol 75 (9) ◽  
pp. 1525-1533 ◽  
Author(s):  
Matias Braccini ◽  
Simon de Lestang ◽  
Rory McAuley
Keyword(s):  
Large Scale ◽  
Fork Length ◽  
Austral Summer ◽  
Seasonal Migration ◽  
Marine Predator ◽  
Marine Predators ◽  
The North ◽  
Large Scale Network ◽  
Carcharhinus Obscurus ◽  
Scale Network

Understanding the large-scale migrations of marine predators can allow better representation of their population dynamics. The migration biology of dusky sharks (Carcharhinus obscurus), a cosmopolitan large marine predator with very low resilience to fishing, was quantified using a large-scale network of acoustic receivers deployed across Western Australia. Time-series plotting of individual shark detections and modified logistic modelling were used to determine the timing of acoustically tagged sharks’ seasonal migration, the proportion of the population migrating, and the size at which sharks start to migrate. Large (>200 cm fork length) dusky sharks migrated between areas closed (north) and open (south) to commercial shark fishing. There was limited evidence that smaller sharks occurred in the northern study area, whereas several larger individuals of both sexes undertook repeated north–south displacements, moving between disparate ecosystems within the Indian Ocean (21.7°S–35.4°S) and covering round-trip distances of 2000–3000 km per migratory event. For migrating individuals, the probability of occurring in the north was high in the austral winter–spring and low (males) to moderate (females) during the austral summer–autumn.

Characterization and evolution of spearfishing in Madeira archipelago, Eastern Atlantic

2020 ◽  
Vol 33 ◽  
pp. 15
Author(s):  
Roi Martínez-Escauriaza ◽  
Claudio Vieira ◽  
Lídia Gouveia ◽  
Nuno Gouveia ◽  
Margarida Hermida
Keyword(s):  
Fish Species ◽  
Young Men ◽  
Coastal Areas ◽  
Teleost Fishes ◽  
The North ◽  
Southeast Coast ◽  
Madeira Archipelago ◽  
First Time

Data obtained from licenses of spearfishers and surveys conducted in 2004 and 2017 allowed for the analysis, for the first time, of the practice of spearfishing in the Madeira archipelago. Only a small percentage of the population practices spearfishing, mostly local young men. Most of them practice the activity with a partner throughout most of the year and along most of the island's coastal areas, although preferentially along the North and Southeast coast. Results show how, in recent years, despite the population of spearfishers decreasing, the abundance in the annual catch potentially increased, probably due to the higher investment of time in this activity. It has been observed that many fishers complement their catches with manual collecting of invertebrates. Overall, 40 teleost fishes and also 4 crustaceans and 8 molluscs were identified. The most frequently captured fish species were parrotfish and white seabream, while limpets were the most collected invertebrates in both selected periods.

Why Has There Been No People’s Power Rebellion in North Korea?

2018 ◽  
pp. 1-34
Author(s):  
Andrew Jackson
Keyword(s):  
Rural Areas ◽  
North Korea ◽  
Large Scale ◽  
Political Elite ◽  
Information Control ◽  
Al Jazeera ◽  
The North ◽  
New Information ◽  
Effective System ◽  
The Right

One scenario put forward by researchers, political commentators and journalists for the collapse of North Korea has been a People’s Power (or popular) rebellion. This paper analyses why no popular rebellion has occurred in the DPRK under Kim Jong Un. It challenges the assumption that popular rebellion would happen because of widespread anger caused by a greater awareness of superior economic conditions outside the DPRK. Using Jack Goldstone’s theoretical expla-nations for the outbreak of popular rebellion, and comparisons with the 1989 Romanian and 2010–11 Tunisian transitions, this paper argues that marketi-zation has led to a loosening of state ideological control and to an influx of infor-mation about conditions in the outside world. However, unlike the Tunisian transitions—in which a new information context shaped by social media, the Al-Jazeera network and an experience of protest helped create a sense of pan-Arab solidarity amongst Tunisians resisting their government—there has been no similar ideology unifying North Koreans against their regime. There is evidence of discontent in market unrest in the DPRK, although protests between 2011 and the present have mostly been in defense of the right of people to support themselves through private trade. North Koreans believe this right has been guaranteed, or at least tacitly condoned, by the Kim Jong Un government. There has not been any large-scale explosion of popular anger because the state has not attempted to crush market activities outright under Kim Jong Un. There are other reasons why no popular rebellion has occurred in the North. Unlike Tunisia, the DPRK lacks a dissident political elite capable of leading an opposition movement, and unlike Romania, the DPRK authorities have shown some flexibility in their anti-dissent strategies, taking a more tolerant approach to protests against economic issues. Reduced levels of violence during periods of unrest and an effective system of information control may have helped restrict the expansion of unrest beyond rural areas.

Information And Map-Made Control With The Functions Of Business Analytics For Urban Management

2019 ◽  
pp. 72-78
Keyword(s):  
Large Scale ◽  
Information Support ◽  
Urban Management ◽  
Business Analytics ◽  
Administrative District ◽  
The North ◽  
Model Of Management ◽  
Complex Development ◽  
Coordination System ◽  
Key Aspects

The key aspects of the process of designing and developing an information and cartographic control tool with business analytics functions for the municipal level of urban management are considered. The review of functionality of the developed tool is given. Examples of its use for the analysis and monitoring of implementation of the program of complex development of territories are given. The importance of application of information support of management and coordination at all levels of management as an integral part of the basic model of management and coordination system of large-scale urban projects of dispersed construction is proved. Information and map-made tool with business intelligence functions was used and was highly appreciated in the preparation of information-analytical and presentation materials of the North-Eastern Administrative District of Moscow. Its use made it possible to significantly optimize the list of activities of the program of integrated development of territories, their priority and timing.

Scheming

2018 ◽  
Author(s):  
Seán Damer
Keyword(s):  
Social Class ◽  
Housing Policy ◽  
Large Scale ◽  
Class Structure ◽  
Local Council ◽  
Housing Scheme ◽  
Post War ◽  
First Time ◽  
The Voice ◽  
House Building

This book seeks to explain how the Corporation of Glasgow, in its large-scale council house-building programme in the inter- and post-war years, came to reproduce a hierarchical Victorian class structure. The three tiers of housing scheme which it constructed – Ordinary, Intermediate, and Slum-Clearance – effectively signified First, Second and Third Class. This came about because the Corporation uncritically reproduced the offensive and patriarchal attitudes of the Victorian bourgeoisie towards the working-class. The book shows how this worked out on the ground in Glasgow, and describes the attitudes of both authoritarian housing officials, and council tenants. This is the first time the voice of Glasgow’s council tenants has been heard. The conclusion is that local council housing policy was driven by unapologetic considerations of social class.

Sphagnum mosses (Sphagnaceae, Bryophyta) of mires Chefandzar and Masota in North Ossetia (Caucasus)

2018 ◽  
Vol 52 (2) ◽  
pp. 455-462 ◽  
Author(s):  
G. Ya. Doroshina ◽  
I. A. Nikolajev
Keyword(s):  
Plant Communities ◽  
The Other ◽  
North Caucasus ◽  
Sphagnum Mosses ◽  
Greater Caucasus ◽  
The North ◽  
First Time ◽  
North Ossetia

Sphagnum mires on the Greater Caucasus are rare, characterized by the presence of relict plant communities of glacial age and are in a stage of degradation. The study of Sphagnum of Chefandzar and Masota mires is carried out for the first time. Seven species of Sphagnum are recorded. Their distribution and frequency within the North Caucasus are analyzed. Sphagnum contortum, S. platyphyllum, S. russowii, S. squarrosum are recorded for the first time for the study area and for the flora of North Ossetia. The other mosses found in the study area are listed.

Materials to the lichen flora of Samurskiy Ridge (high mountainous Dagestan)

2018 ◽  
Vol 52 (2) ◽  
pp. 397-406
Author(s):  
A. B. Ismailov ◽  
G. P. Urbanavichus
Keyword(s):  
North Caucasus ◽  
Lichenicolous Fungi ◽  
Greater Caucasus ◽  
Altitudinal Range ◽  
The North ◽  
New Findings ◽  
Mountainous Landscapes ◽  
First Time ◽  
Lichen Flora

The lichens and lichenicolous fungi of high mountainous landscapes of Samurskiy Ridge were studied in altitudinal range 2400–3770 m a. s. l. for the first time and 112 species are recorded. Among them 33 species, 10 genera (Arthrorhaphis, Baeomyces, Calvitimela, Epilichen, Lambiella, Psorinia, Rufoplaca, Sagedia, Sporastatia, Tremolecia) and 4 families (Anamylopsoraceae, Arthrorhaphidaceae, Baeomycetaceae, Hymeneliaceae) are new for Dagestan, six species (Buellia uberior, Carbonea atronivea, Lecanora atrosulphurea, Lecidea fuliginosa, L. swartzioidea, Rhizoplaca subdiscrepans) are reported for the first time for the Greater Caucasus and two species (Acarospora subpruinata and Rhizocarpon postumum) — for the North Caucasus. Most of the new findings were collected from 3500–3770 m a. s. l.

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