Wildlife

Bats vs. Turbines

A new study estimates that more than 600,000 bats are killed each year by the rotation of wind turbines in the continental United States.

Wildlife experts say those deaths are in addition to the large numbers of the flying mammals that are being killed by white-nose syndrome, which is caused by a fungus that has spread rapidly to bat caves and mines across North America.

Writing in the journal BioScience, University of Colorado researcher Mark Hays notes that the actual number of bat deaths from the turbines could be much higher than the conservative estimate of 600,000.

The majority of bat species produce only one young per year, meaning that their populations are slow to recover.

Most bats don’t die from actual contact with the turbines since their sonar allows them to avoid the blades.

But subtle changes in barometric pressure created by the rotating blades cause the bats’ capillaries to burst, resulting in deadly internal hemorrhaging.

Birds’ circulatory systems are different from that of bats, keeping them from being victims of such “barotrauma.”

Most bat deaths occur when winds are relatively light because bats can’t fly in high winds. And since most turbines shut down when winds go below about 9 mph anyway, experts say increasing the “cut-in speed” to 11 mph would reduce bat deaths by at least 44 percent.

As much as 93 percent of bat fatalities due to turbine barotrauma could be avoided if the cut-in speed was lifted to 15.6 mph, experts say.

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Disease

New Flu Strain Jumps from Birds to a Human in Asia

A young woman in Taiwan has contracted a new strain of influenza A, which is very similar in structure to the H7N9 bird flu that killed 45 people and infected 139 other in China last year. The H6N1 strain is believed to have come from infected poultry and reacts to the same drugs that combat other strains of bird flu, like Tamiflu and Relenza, according to Taiwan’s Centres for Disease Control.

Researchers there say H6N1 is widespread in poultry but no reported cases of transmission to humans have been found.

The Taiwanese patient fully recovered, and no trace of the virus was found in the 36 people with whom the woman had close contact.

Volcanos

Roundup of Global Volcanic Activity:

Etna (Sicily, Italy): The New SE crater has calmed down. Only very occasionally, a weak glow appeared from the summit vent at night, suggesting deep-seated activity still occurs from time to time.

Klyuchevskoy (Kamchatka): Activity has generally decreased over the past days. VAAC Tokyo reported a possible eruption early today, producing a small ash plume rising to 17,000 ft (5.1 km), i.e. a few hundred meters tall. Webcam images at that time are cloudy, but otherwise show the volcano is mostly quiet.

Sakurajima (Kyushu, Japan): Activity seems to increase and decrease in cycles of approximately a week’s length. After the series of stronger explosions on 24-25 Nov, the past days have been calmer with fewer and less intense explosions (1-2 per day, ash plumes to 8,000 ft).

Sinabung (Sumatra, Indonesia): Visual activity has decreased. Ash emissions have become less intense and less frequent. However, this could be only a pause, and the risk of larger explosions that can occur unexpectedly remains high.

Dukono (Halmahera): A dense SO2 plume is visible on the latest NOAA satellite data, suggesting that (the ongoing) activity (weak to moderate strombolian explosions) is elevated at the moment.

Popocatépetl (Central Mexico): CENAPRED reports no changes in activity. The number of explosive emissions of gas/steam and minor amounts of ash is very low (less than 10 per day). Weak glow remains visible at night and SO2 emissions elevated.

A volcano-tectonic quake of magnitude 2.2 was recorded yesterday at 04:33 local time.

Santa María / Santiaguito (Guatemala): Activity has been mainly effusive during the past days; no or few explosions occurred yesterday. The volcano observatory reports abundant avalanches from the active lava flows mainly on the NE side of the Caliente lava dome.

Pacaya (Guatemala): INSIVUMEH reports continuing weak strombolian activity. Small ash plumes at altitudes of 2.5-2.7 km drift up to approx. 10 km mainly to the SE.

Fuego (Guatemala): No significant changes in activity have occurred. The volcano produces small to moderate strombolian-type explosions with ash plumes rising up to about 800 m. The lava flows are no longer active.