Earth ChangesS


Ship-induced Waves Affect Snails, Crabs And Insect Larvae In Sandy Lakes And Rivers

Snails, crabs, insect larvae - the shores of rivers and lakes are populated by thousands of small animals that play an important role in the food chain of the freshwater ecosystem. They eat the leaves, among other things, which fall into the water, and so keep the waters clean.

©iStockphoto/Brent Bossom
Okanagan Lake in Kelowna, British Columbia, Canada. Waves affect snails and insect larvae more on sandy shores than shores with tree roots or reeds.

Up to 10,000 organisms can be found on a square meter of water bottom, of which a lot are also terrestrial insect larvae. Scientists call the whole group macrozoobenthos - these are all invertebrates living on the bottom and still visible with naked eyes. Researchers at the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) now study the impact that ship-induced waves can have on these small animals.

The larva of Calopteryx splendens, a dragonfly, crawls on a stone in shallow water. Then operates Friederike Gabel the wave machine. A wave, comparable to that of a sport boat, runs along the three-metre-long canal.

The larva is washed out - "detached" say the researchers - and paddle around several minutes helplessly in the water until it found again the "solid ground" under its feet. "If they stay suspended in the water, the larvae take the risk to be eaten" explains F. Gabel, a specialist of the effect of waves on invertebrates. In addition, the larva spent energy to fix them back, which has negative effects on their growth and reproduction. The researchers fear that ship-induced waves increase larval mortality and subsequently biodiversity, which would have a long-term effect on the ecological quality of rivers and lakes.


Explorers Find Hundreds Of Undescribed Corals, Other Species On Familiar Australian Reefs

Hundreds of new kinds of animal species surprised international researchers systematically exploring waters off two islands on the Great Barrier Reef and a reef off northwestern Australia -- waters long familiar to divers.

©Gary Cranitch, Queensland Museum, 2008
Ctenophore, or comb jelly, collected off Wassteri Reef, Heron Island.

The expeditions, affiliated with the global Census of Marine Life, help mark the International Year of the Reef and included the first systematic scientific inventory of spectacular soft corals, named octocorals for the eight tentacles that fringe each polyp.

The explorers have released some initial results and stunning images from their landmark four-year effort to record the diversity of life in and around Australia's renowned reefs.

Bizarro Earth

5.0 Magnitude Earthquake shakes south Iran

Tehran - A magnitude 5 earthquake struck southern Iran on Wednesday near the port of Bandar Abbas, site of a major oil refinery, Iranian media reported, without mentioning any casualties or damage.

The same region was hit by a 6.1 magnitude earthquake last week that killed at least seven people.

The U.S. Geological Survey (USGS) estimated the magnitude of Wednesday's quake at 5.2 and said it happened at 9:13 p.m. local time (1643 GMT).

Iran's official IRNA news agency said the quake hit the island of Qeshm off the coast and cut electricity there. People had rushed onto the streets, it said, giving no further details.

USGS said it struck 40 km (25 miles) southwest of Bandar Abbas.


Indonesia: Moderate earthquake strikes Waingapu

Bengkulu - A tectonic earthquake measuring 5.0 on the Richter scale jolted East Nusa Tenggara town of Waingapu at 5:38 local time on Wednesday morning, Meteorology and Geophysics Agency (BMG) said.


India: Earthquake measuring 4.7 shakes Maharashtra

There was an earthquake in the State if Maharashtra, India with the magnitude of 4.7 on the Richter scale.


No 2008 record for Arctic sea ice

The ice has covered a larger area this year, though much has been thinner

Sea ice in the Arctic appears to have passed its minimum extent for 2008 without breaking last year's record.

The US National Snow and Ice Data Center (NSIDC) says the ice covered 4.5 million sq km (1.7 million sq miles) at its lowest point on 12 September.

Last year's minimum was 4.1 million sq km (1.6 million sq miles).

This summer's ice cover was the second lowest since satellite records began 30 years ago, which NSIDC says emphasises the "strong negative trend".

Comment: For a long range view, we recommend this.

Bizarro Earth

Volcanic ash blankets Papua New Guinea's Rabaul

Volcanic activity in the Papua New Guinea town of Rabaul is now at its highest point since the devastating eruption of 1994 which wiped out two thirds of the town.

Up to 40 centimetres of volcanic ash blankets the community and surrounding mountains.

Up to 40 centimetres of volcanic ash blankets the community and surrounding mountains.

There are concerns the oncoming wet season rains will create mudslides.

Ima Itikarai from the Rabaul Observatory says ash on rooftops is also a problem because it turns to mud in rains, collapsing some homes.


Gilchrist, the village that Ike wiped off the Texas map

The sunset is beautiful in Gilchrist - within just a few minutes the sky goes from red to indigo and then to a wide range of grey before turning the black of night.

single house
©EPA/Smiley N. Pool
A single house is left standing on the waterfront near Gilchrist, Texas, USA on 14 September 2008 following the destruction along the Texas coast. As Hurricane Ike slowed to a tropical depression after carving a path of destruction through Texas, rescuers were using everything from dump trucks to boats and helicopters to reach stranded residents.

Arrow Down

House approves offshore drilling

WASHINGTON - The House voted late Tuesday to open waters off the Atlantic and Pacific coasts to oil and gas drilling but only 50 or more miles out to sea and only if a state agrees to energy development off its shore.

Better Earth

Whale Songs Are Heard For First Time Around New York City Waters

For the first time in waters surrounding New York City, the beckoning calls of endangered fin, humpback and North Atlantic right whales have been recorded, according to experts from the Bioacoustics Research Program at the Cornell Lab of Ornithology and the New York State Department of Environmental Conservation (DEC).

humpback whale
©iStockphoto/Eric Carr
A humpback whale (Megaptera novaeangliae) breaching. Its long pectoral fins, tubercles, and ventral grooves that run from the lower jaw to the umbilicus are visible.

"This is an exciting time for New Yorkers. Just think, just miles from the Statue of Liberty, the Empire State Building, Carnegie Hall and Times Square, the great whales are singing," says Chris Clark, the Director of the Bioacoustics Research Program at the Cornell Lab of Ornithology. "These are some of the largest and rarest animals on this planet trying to make a living just a few miles from New York's shores. It just goes to show us that there are many important and wonderful discoveries to be made about the living world right here, right in our back yards."

"With data generated by acoustic monitoring, we can better understand New York's role in the life history of these endangered whales and make more informed conservation decisions," says James Gilmore, chief of the DEC's Bureau of Marine Resources. "This is especially important for the survival of right whales."