Molecular mechanism links temperature with sex determination in some fish species

Researchers have found the epigenetic mechanism that links temperature and gonadal sex in fish. High temperature increases DNA methylation of the gonadal aromatase promoter in females.

Sunlight and bunker oil a fatal combination for Pacific herring

The 2007 Cosco Busan disaster, which spilled 54,000 gallons of oil into the San Francisco Bay, had an unexpectedly lethal impact on embryonic fish, devastating a commercially and ecologically important species for nearly two years, reports a new study.

Sea cucumbers: Dissolving coral reefs?

Coral reefs are extremely diverse ecosystems that support enormous biodiversity. But they are at risk. Carbon dioxide emissions are acidifying the ocean, threatening reefs and other marine organisms. New research analyzed the role of sea cucumbers in portions of the Great Barrier Reef and determined that their dietary process of dissolving calcium carbonate (CaCO3) from the surrounding reef accounts for about half of at the total nighttime dissolution for the reef.

Ocean acidification: Some organisms already experiencing ocean acidification levels not predicted to be reached until 2100

Ocean acidification research is a relatively new study topic as scientists have only appreciated the potential extent of acidification within the last decade. As greenhouse gas emissions have accelerated in the past century, the oceans have taken up about a third of the carbon dioxide produced by human activities. That excess beyond natural levels increases amounts of carbonic acid in seawater. New research shows that some organisms are already experiencing ocean acidification levels not predicted to be reached until 2100.

Belize protected area boosting predatory fish populations

A 14-year study in an atoll reef lagoon in Glover's Reef, Belize has found that fishing closures there produce encouraging increases in populations of predatory fish species. However, such closures have resulted in only minimal increases in herbivorous fish, which feed on the algae that smother corals and inhibit reef recovery.

How diving marine mammals manage decompression

How do marine mammals, whose very survival depends on regular diving, manage to avoid decompression sickness or "the bends?" Do they, indeed, avoid it?

Will Antarctic worms warm to changing climate?

Researchers are examining tiny worms that inhabit the frigid sea off Antarctica to learn not only how these organisms adapt to the severe cold, but how they will survive as ocean temperatures increase.

Barracuda babies: Novel study sheds light on early life of prolific predator

Marine biologists shed light on the larval stage of the barracuda, as well as several other closely related species.

Nitrogen from humans pollutes remote lakes for more than a century

Nitrogen derived from human activities has polluted lakes throughout the Northern Hemisphere for more than a century and the fingerprint of these changes is evident even in remote lakes located thousands of miles from the nearest city, industrial area or farm. The findings are based on historical changes in the chemical composition of bottom deposits in lakes using an approach similar to aquatic archeology.

140 new species described by California Academy of Sciences in 2011

In 2011, researchers at the California Academy of Sciences added 140 new relatives to our family tree. The new species include 72 arthropods, 31 sea slugs, 13 fishes, 11 plants, nine sponges, three corals, and one reptile. They were described by more than a dozen Academy scientists along with several dozen international collaborators.

Life on Kosterhavet's seabed analyzed

Kosterhavet National Park was created to provide a haven for both protected species and nature lovers. Now researchers have analyzed species living on the seabed (benthic species) in the marine national park to determine which marine areas require special protection.

Elephant seal travels 18,000 miles

Scientists tracked a southern elephant seal for an astonishing 18,000 miles -- the equivalent of New York to Sydney and back again.

Comprehensive view of the status of Atlantic bluefin tuna

Bluefin populations on both sides of the Atlantic Ocean have declined precipitously since 1950, according to a new study. The model estimates the number of Atlantic bluefin tuna remaining in the ocean and projects future population sizes based on alternative management scenarios. The new model is revolutionary in its ability to account for population overlap (mixing) of this highly migratory animal on the North Atlantic foraging grounds.

Expanding dead zones are shrinking tropical blue marlin habitat

Scientists sound an alarm that expanding ocean dead zones are shrinking the habitat for high value fish such as marlins, other billfish and tunas in the tropical northeast Atlantic Ocean. Without taking this phenomena into account, scientific fish stock assessments could provide false signals that stocks are healthy, when in fact they are not, thus allowing overfishing that further depletes these fish stocks.

The physics behind great white shark attacks on seals

A new study examines the complex and dynamic interactions between white sharks and Cape fur seals in False Bay, South Africa; Offers new insights on physical and biological factors underlying predator-prey interactions in marine environment.

Genetic markers help feds enforce seafood regulations

New discoveries in "marine forensics" will allow federal seafood agents to genetically test blue marlin to quickly and accurately determine their ocean of origin. The test is needed to ensure that the blue marlin sold in US seafood markets were not taken from the Atlantic Ocean. Regulation of Atlantic blues reflects overfishing and a troubling drop in population.

Sandeels with a full stomach swim for a longer time

Researchers have shed light on the peculiar behavior of the commercially and ecologically valuable sandeel.

Marine predators in trouble

Iconic marine predators such as sharks, tunas, swordfish, and marlins are becoming increasingly rare under current fishing trends, say researchers.

When the heat's on, some fish can cope: Certain tropical species have greater capacity to deal with rising sea temperatures than thought

Australian scientists have discovered that some tropical fish have a greater capacity to cope with rising sea temperatures than previously thought – by adjusting over several generations. The discovery sheds a ray of hope amid the rising concern over the future of coral reefs and their fish under the levels of global warming expected to occur by the end of this century.

Global warming changes balance between parasite and host in fish

Worms infecting fish grow four times faster at higher temperatures and manipulate the behavior of fish.