نتایج جستجو برای: marine mammals

تعداد نتایج: 134570  

2013

Brucella infections have recently been recognized in seals, sea lions, walruses, dolphins, porpoises, whales and an otter. This organism appears to be widespread in marine mammals, and has probably been endemic in these populations for a long time. The clinical significance is uncertain. A few infections have been associated with placentitis/abortions, neonatal mortality, meningoencephalitis, a...

2015
Qiuling Yang Yishan Su Zhigang Jin Guidan Yao

In oceans, the limited acoustic spectrum resource is heavily shared by marine mammals and manmade systems including underwater sensor networks. In order to limit the negative impact of acoustic signal on marine mammals, we propose an environmentally friendly power control (EFPC) scheme for underwater sensor networks. EFPC allocates transmission power of sensor nodes with a consideration of the ...

2006
P. T. Madsen P. Tyack

The demand for renewable energy has led to construction of offshore wind farms with high-power turbines, and many more wind farms are being planned for the shallow waters of the world’s marine habitats. The growth of offshore wind farms has raised concerns about their impact on the marine environment. Marine mammals use sound for foraging, orientation and communication and are therefore possibl...

2001
Ron Abileah

A new era of commercial high-resolution imagery from space began late in 1999 resulting in resolution that is now sufficient to resolve marine mammals. This encouraged investigating the use of satellite imagery for marine-mammal population census and related studies. The question was raised: Can marine mammals be reliably detected above sensor noise and ocean clutter? To answer this question, a...

Journal: :Marine pollution bulletin 2016
Christine Erbe Colleen Reichmuth Kane Cunningham Klaus Lucke Robert Dooling

Underwater noise, whether of natural or anthropogenic origin, has the ability to interfere with the way in which marine mammals receive acoustic signals (i.e., for communication, social interaction, foraging, navigation, etc.). This phenomenon, termed auditory masking, has been well studied in humans and terrestrial vertebrates (in particular birds), but less so in marine mammals. Anthropogenic...

2015
Olaf Boebel Daniel P. Zitterbart

Growing concerns that aquatic noise produced during naval exercises and offshore seismic surveys may be harmful to marine mammals, have led an increasing number of regulating agencies to request mitigation measures when issuing permits for such surveys in their nations’ EEZ. The most common measure is to implement a “marine mammal watch”, a team of observers that scans the ship’s environs for s...

Journal: :Journal of toxicology and environmental health. Part A 2008
Chiharu Mori Brenda Morsey Milton Levin Timothy S Gorton Sylvain De Guise

Organochlorines (OC) are lipophilic and stable, and therefore accumulate in tissues of top predators, such as marine mammals. While the immunomodulatory effects of individual OC have been studied in lab animals, their effects in other species (such as marine mammals) and the possible interactions between chemicals in mixtures are not well understood. This study investigated the immunomodulatory...

Journal: :Reviews of environmental contamination and toxicology 2008
Takashi Kunito Reiji Kubota Junko Fujihara Tetsuro Agusa Shinsuke Tanabe

Although there have been numerous studies on arsenic in low-trophic-level marine organisms, few studies exist on arsenic in marine mammals, seabirds, and sea turtles. Studies on arsenic species and their concentrations in these animals are needed to evaluate their possible health effects and to deepen our understanding of how arsenic behaves and cycles in marine ecosystems. Most arsenic in the ...

2001
Michael A. Perez W. Bruce McAlister

One important aspect of the management of commercial fisheries in an ecosystem context involves understanding the diet and consumption rates of fish species by their natural predators. Such knowledge allows for comparison of commercial fish catches with consumption through predation by species groups such as marine mammals. For the Bering Sea, the limited data available only allows a preliminar...

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