Stable isotope profiles in sperm whale teeth: variations between areas and sexes

2007 ◽  
Vol 87 (2) ◽  
pp. 621-627 ◽  
Author(s):  
Sónia Mendes ◽  
Jason Newton ◽  
Robert J. Reid ◽  
Alexandros Frantzis ◽  
Graham J. Pierce
Keyword(s):  
Stable Isotope ◽  
Indian Ocean ◽  
Mediterranean Sea ◽  
Marked Change ◽  
Sperm Whale ◽  
Population Substructure ◽  
Isotopic Ratios ◽  
Physeter Macrocephalus ◽  
The Indian Ocean ◽  
The Mediterranean

Sperm whale (Physeter macrocephalus) teeth were used to investigate whether variation in the chronological profiles of carbon and nitrogen stable isotope ratios along dentine growth layers could reflect differences in ontogenetic movements and/or dietary shifts in animals from different regions and sexes, as well as to show the differences in the isotopic environments experienced by these animals. Absolute isotopic ratios ranged from -14.1 to -11.0‰ for carbon and 10.8 to 18.1‰ for nitrogen, with the whale from the Indian Ocean, the two from the Mediterranean Sea and the female from the Azores presenting the most different median isotopic ratios. The Icelandic and the Indian Ocean males showed the expected decrease in δ13C around the age of ten, denoting male segregation from natal groups. For the latter, this was larger by almost twofold compared to other teeth, probably due to the much stronger latitudinal gradient in planktonic δ13C in the southern hemisphere. The Mediterranean Sea whales exhibited the lowest median δ15N values, probably reflecting the oligotrophy of this sea, while the male showed a marked change in isotopes around the age of 20 that could indicate a move to the eastern basin or a temporal change in basal isotopic signatures. The Atlantic females did not show a marked change in δ13C as expected since they stay in low latitudes throughout their lives. Stable isotope profiles in whale teeth can be used to investigate differences in the timings of ontogenetic movements and dietary history between individuals and sexes, and the biogeochemistry of different regions inhabited, and have the potential to allow inferences to be made about population substructure.

Ectoenzymatic activity in surface waters: A transect from the Mediterranean Sea across the Indian Ocean to Australia

2006 ◽  
Vol 53 (9) ◽  
pp. 1517-1532 ◽  
Author(s):  
C. Misic ◽  
M. Castellano ◽  
M. Fabiano ◽  
N. Ruggieri ◽  
V. Saggiomo ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Mediterranean Sea ◽  
Surface Waters ◽  
The Indian Ocean ◽  
The Mediterranean

Summer social distribution of sperm whales (Physeter macrocephalus) in the Mediterranean Sea

2004 ◽  
Vol 84 (3) ◽  
pp. 675-680 ◽  
Author(s):  
Violaine Drouot ◽  
Alexandre Gannier ◽  
John C. Goold
Keyword(s):  
Mediterranean Sea ◽  
Sperm Whale ◽  
Northern Region ◽  
The Body ◽  
Southern Region ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
The North ◽  
Social Distribution ◽  
The Mediterranean

Sperm whale social distribution was investigated in the Mediterranean Sea, using data collected during summer surveys from 1997 to 2002. Variations in the size of sperm whale schools/underwater aggregations were assessed using both visual and acoustic data. Individual body lengths were estimated acoustically, using the click inter-pulse intervals. Regional comparisons were undertaken, taking the 41° parallel as a north/south boundary. In the southern region, schools of up to seven sperm whales were sighted and calves were relatively frequent. The animals ranged between 8·6 m and 13·1 m long. In the northern region, school sizes were significantly smaller, with a maximum of three whales sighted at the surface. However, the acoustic survey showed that sperm whales form loose aggregations of up to five animals in certain areas. Whales detected in the north were 12·6 m long on average, and the body size range was relatively small. This summer survey demonstrated a segregation of males, in the north, from larger schools including calves, which seemed to be confined to the southern region.

scholarly journals Assimilation of radar altimeter data in numerical wave models: an impact study in two different wave climate regions

2007 ◽  
Vol 25 (3) ◽  
pp. 581-595 ◽  
Author(s):  
G. Emmanouil ◽  
G. Galanis ◽  
G. Kallos ◽  
L. A. Breivik ◽  
H. Heiberg ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Mediterranean Sea ◽  
European Space Agency ◽  
Wave Climate ◽  
Altimeter Data ◽  
Radar Altimeter ◽  
The Indian Ocean ◽  
Numerical Wave ◽  
The Mediterranean ◽  
Wave Models

Abstract. An operational assimilation system incorporating significant wave height observations in high resolution numerical wave models is studied and evaluated. In particular, altimeter satellite data provided by the European Space Agency (ESA-ENVISAT) are assimilated in the wave model WAM which operates in two different wave climate areas: the Mediterranean Sea and the Indian Ocean. The first is a wind-sea dominated area while in the second, swell is the principal part of the sea state, a fact that seriously affects the performance of the assimilation scheme. A detailed study of the different impact is presented and the resulting forecasts are evaluated against available buoy and satellite observations. The corresponding results show a considerable improvement in wave forecasting for the Indian Ocean while in the Mediterranean Sea the assimilation impact is restricted to isolated areas.

Seismic Refraction Experiments in the Indian Ocean and in the Mediterranean Sea

Nature ◽  
1953 ◽  
Vol 172 (4377) ◽  
pp. 535-537 ◽  
Author(s):  
T. F. GASKELL ◽  
J. C. SWALLOW
Keyword(s):  
Indian Ocean ◽  
Mediterranean Sea ◽  
Seismic Refraction ◽  
The Indian Ocean ◽  
The Mediterranean

The Red Sea

2012 ◽  
Author(s):  
Lucy Blue
Keyword(s):  
Indian Ocean ◽  
Mediterranean Sea ◽  
Red Sea ◽  
Traditional View ◽  
Maritime Trade ◽  
Archaeological Record ◽  
Maritime Traffic ◽  
The Indian Ocean ◽  
The Mediterranean ◽  
Insight Into

The Red Sea has been always an important highway for maritime trade and shipping. The prevailing winds greatly influence the way that ancient seafarers navigate these waters, contributing to the traditional view that the Red Sea served as a barrier to maritime communications. Despite this, frequent maritime traffic, and remarkably few shipwrecks have been discovered in this region. This article addresses limited shipwreck evidence and draws on a range of diverse evidence, in order to provide some insight into the maritime archaeological record of the Red Sea. It summarizes the available maritime archaeological records regarding the Red Sea. However, there is much more to be discovered and learned about this region as it has stimulated maritime contact, communication and trade along the waterway, and opening channels to the Indian Ocean and the Mediterranean Sea.

scholarly journals MIDDLE EAST AND NORTH AFRICA AS A PART OF CHINESE STRING OF PEARLS STRATEGY

2020 ◽  
pp. 60-71
Author(s):  
Aghavni HARUTYUNYAN
Keyword(s):  
Middle East ◽  
Indian Ocean ◽  
Mediterranean Sea ◽  
North Africa ◽  
Persian Gulf ◽  
Development Economic ◽  
The Indian Ocean ◽  
The Mediterranean ◽  
The Persian Gulf ◽  
String Of Pearls

Launched by Chinese President Xi Jinping in 2013, the One Belt, One Road initiative (OBOR), which consists of land (EBSR) and sea routes (MSR), aims to connect Asia and Europe through the Middle East, Africa and Central Asia. The MSR strategy focuses on creating Chinese strongholds or “naval posts” with military or geopolitical influence along the Indian Ocean littoral, the Persian Gulf and the Mediterranean Sea, called a “String of Pearls” - similar to the “Dual Use Logistics Facility”. It is related to Beijing’s need for geostrategic security of the “choke points” and maritime [oil and trade] routes critical of its development and based on China’s need to establish an increased level of influence and advanced presence along the sea routes through the use of investment, port development, economic, political, diplomatic and military means. China hopes to contribute to strengthening regional security on the southern gateway from the Indian Ocean to the Red Sea and the Suez Canal, one of the world’s biggest shipping lanes and a pivotal part of the MSR. Today the Chinese energy security policy has been militarized by creating a navy and deploying troops to protect and implement energy and infrastructure projects in the Middle East and North Africa region. It is an important hub for the two OBOR routes due to its strategic location at the intersection of land and sea roads connecting Asia, Africa and Europe, and the three most important economic maritime regions: the South China Sea, the Persian Gulf, and the Mediterranean Sea.

scholarly journals Model study of the circulation of the Miocene Mediterranean Sea and Paratethys: closure of the Indian Gateway

2013 ◽  
Vol 9 (4) ◽  
pp. 4385-4424 ◽  
Author(s):  
A. de la Vara ◽  
P. Th. Meijer ◽  
M. J. R. Wortel
Keyword(s):  
Indian Ocean ◽  
Mediterranean Sea ◽  
Mediterranean Basin ◽  
Water Exchange ◽  
Ocean Dynamics ◽  
Atmospheric Forcing ◽  
The Indian Ocean ◽  
The Mediterranean ◽  
Indian And Atlantic Oceans ◽  
The Mediterranean Basin

Abstract. The early Mediterranean Sea and the Paratethys were both connected to the Indian Ocean until the Early/Middle Miocene, when the convergence of the Eurasian and African-Arabian plates caused the constriction and final closure of the Indian Gateway. Although little is certain concerning the timing of the closure and the consequences that it entailed, it is broadly accepted that it had a large effect on water properties and ocean dynamics on the regional and global scales and, in that way, may have also played a role in the evolution of climate. The purpose of this work is to investigate the palaeocirculation of the Mediterranean Sea and the Paratethys during different stages of closure and the impact of this event on the water exchange between the Mediterranean and the adjacent Indian and Atlantic oceans. To this extent we use a regional ocean model and an Early Miocene palaeogeographic map. In addition to varying the depth of the Indian Gateway, different sets of values for the atmospheric forcing have been applied in order to check the robustness of our results and to understand the role of the temperature and net evaporation on the marine circulation and the strait dynamics. The series of experiments performed shows that, with an Indian Gateway ranging from 1000 to 460 m deep, the Mediterranean accommodates anti-estuarine exchange to the Indian and Atlantic oceans. The shoaling of the Indian Gateway results in a progressive decrease in the water exchanged between the Indian Ocean and the Mediterranean basin, and increases the spatial extension of the Atlantic inflow. When the gateway is as shallow as 220 m, there is no effective water exchange between the Indian Ocean and the Mediterranean basin, suggesting that the gateway may have been closed in an oceanographical sense, even while a water passage was still in existence. On a basinal scale, closure results in a rearrangement of the circulation pattern which leads to changes in salinity and temperature in both the Paratethys and the Mediterranean Sea. On the global scale, closure implies the disappearance of a source of dense outflow into the Indian Ocean which could have played a role in the development of the East Antarctic Ice Sheet. The additional experiments show that the response to gateway shoaling is largely independent of the assumed atmospheric forcing.

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