SustyVibes

Too hot for flying bats and male birth

What sounds like a line from the Book of Revelation is in fact currently happening in Australia. It’s not a sign of the impending Apocalypse (hopefully) but of an extreme heat wave that has gripped the country. The bats in question – gray-headed flying foxes – can weigh as much one kilogram (2.2 lbs.) with a wingspan of up to one meter (3.3 feet).

They mainly eat nectar, pollen and fruit and are a common sight in south-eastern Australia. But they don’t fare well when temperatures rise significantly above 30 degrees celcius (86 F). Australia’s south-east has been experiencing a serious heat wave in recent days with thermometers showing readings as high as 47.8 C. As a result, the megabats, young ones in particular, have been dropping from the skies. Dead. At last count, 204 animals had been killed by the heat.

In the northern part of Australia’s Great Barrier Reef. Warm temperatures there have led to a massive gender shift among sea turtles. This is due to the fact that sea turtles are among those species whose gender is determined by the temperature the eggs are exposed to during incubation. When it’s colder, they become male, when it’s warmer, they become female. A new study has found a staggering 99.1 percent of juveniles and 99.8 percent of subadults in that part of the ocean are now female, as well as 86.8 percent of adults.

By comparison, the population around the southern Great Barrier Reef is only 65 to 69 percent female. Unless the waters start to cool in the coming years, it may soon be “women only” for the turtles. That could have a devastating effect on the population once the juveniles reach adulthood and find very few, if any, male turtles to mate with.

 

Source: DW