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Gulf of Mexico Dead Zone Severely Impairs Reproduction in Atlantic Croaker, Researchers Find

By Guest PostJune 16, 2011Environment, Scienceandrogens, aromatase, atlantic croaker, coast of louisiana, coastal regions, dead zone, enzyme, estrogens, female sex hormones, fish population, gulf of mexico, hypoxic area, hypoxic coastal zone, hypoxic dead zone, impairment of reproductive output, low oxygen waters, male sex hormones, marine animals, marine science, marine scientist, masculinized, neuroendocrine function, ovarian masculinization, oxygen levels, peter thomas, reproductive impairment, saydur rahman, second largest seasonal hypoxic zone, sperm and eggs, the university of texas at austin, thomas and rahman, world

AUSTIN, Texas — Atlantic croaker living in the large Gulf of Mexico “Dead Zone” exhibit severe reproductive impairment with potential long-term impacts on the fish’s population abundance, researchers from The University of Texas at Austin’s Marine Science Institute have found.

Males and females were found to produce dramatically fewer sperm and eggs. In addition, females in the hypoxic Dead Zone waters were masculinized — some 20 percent actually produced sperm in their ovaries. The sex ratio was also heavily skewed toward males in the hypoxic area. (more…)

Scientists Discover Fossil of Giant Ancient Sea Predator

By Guest PostMay 27, 2011Scienceancient sea creatures, anomalocaridid creature, anomalocaridids, biodiversification, cambrian animals, cambrian explosion, cambrian period, complex ecosystems, deep-water, derek briggs, fossils, marine animals, marine fauna, marine predators, morocco, ordovician period, paleontologists, peter van roy, sea floor, sediment clouds

Paleontologists have discovered that a group of remarkable ancient sea creatures existed for much longer and grew to much larger sizes than previously thought, thanks to extraordinarily well-preserved fossils discovered in Morocco.

The creatures, known as anomalocaridids, were already thought to be the largest animals of the Cambrian period, known for the “Cambrian Explosion” that saw the sudden appearance of all the major animal groups and the establishment of complex ecosystems about 540 to 500 million years ago. Fossils from this period suggested these marine predators grew to be about two feet long. Until now, scientists also thought these strange invertebrates-which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth-died out at the end of the Cambrian. (more…)

Crocodiles 168 Times More Dangerous Than Sharks

By PravdaDecember 14, 2010General, Natureakvatoria, angola, bandundu, bees, cancun, cockpit, congo, croc attacks, crocodiles, daniel philemotte, elephants, hendrik coetzee, hippos, kinshansa, lagoon, lauren faille, malaria, marine animals, Mexico, mosquito, predators, salt water crocodile, shark attacks, sharks, south african guide, stewardess, threat to humans, ukraine, yalta

The fears connected with shark attacks are stronger in the world today than those related to much more dangerous predators – crocodiles. However, crocodiles pose a greater threat to humans than sharks do.

A crocodile snatched Hendrik Coetzee, a South African guide, 35, from his kayak while he led an American expedition into the heart of Congo last week. Two American tourists could only watch the scene in horror as the guide was killed and eaten by the predator. They paddled to safety unharmed. Coetzee’s body has not been recovered.

Stories about croc attacks are just as terrible as they are hopeless. Experts say that it is possible to stay to fight off a shark, but it is much more difficult or even impossible to rescue themselves from an attacking croc. (more…)

Tag Archives: marine animals

Gulf of Mexico Dead Zone Severely Impairs Reproduction in Atlantic Croaker, Researchers Find

Scientists Discover Fossil of Giant Ancient Sea Predator

Crocodiles 168 Times More Dangerous Than Sharks