From John Ray's shorter notes




20 December, 2015

Crocodile baloney

The Warmists never stop.  Always a new scare.  This time its crocs that are going to eat you as a result of global warming.  Why?  Because global warming will drive them towards the cooler waters of Southern Australia.  Just one problem:  Crocs are reptiles and they LIKE warmth. The warmer they are, the more active they are.  So where are they generally found?  In TROPICAL Australia -- around Cape York Peninsula and the Top End.  It's the HOTTEST part of Australia that they like.  They vote with their feet to show the best habitat for themselves. No wonder those who know crocodiles well in the wild dismiss the laboratory study reported below

And I have done my usual trick of looking up the underlying academic journal article (Diving in a warming world: the thermal sensitivity and plasticity of diving performance in juvenile estuarine crocodiles (Crocodylus porosus)).  When I do that, I often find that the authors have concluded what they wanted to conclude regardless of what their results show.  And so it seems here too.  I note the following sentence in the Abstract: "Maximal dive performances, however, were found to be thermally insensitive across the temperature range of 28–35°C".  Come again?  28–35°C is the temperature range they studied and the central claim of the article is that crocs can't stay underwater for long if the water is hot.  Yet that sentence asserts the exact opposite.  I give up!

The little lady whose Ph.D. research the article was based on -- Essie Rodgers -- would appear to have been very poorly supervised



Essie


Saltwater crocodiles may be forced to migrate from the north of Australia to the southern states because of global warming.

A University of Queensland study has found the man eaters may be ill-equipped to adjust to rising water temperatures, prompting them to migrate to cooler environments.

The researchers found the higher water temperatures hindered their diving ability, putting the young crocs at risk from predators.

Professor Craig Franklin of the university's School of Biological Sciences said they have found crocodiles are not hardwired to adapt to water temperatures – unlike other cold blooded animals.

'It's likely that if the water is too hot, crocodiles might move to cooler regions, or will seek refuge in deep, cool water pockets to defend their dive times,' he said.

Lead author for the study, PhD student Essie Rodgers, said the study showed increases in water temperatures severely shortened crocodiles diving times.

'Crocodiles are ectothermic animals – where environmental temperatures strongly influence their body temperatures,' she said.

The lethal temperature for crocodiles is in the high 30s to low 40s, making water a critical refuge for the reptiles to avoid dehydration.

Experts have cast doubt on the study, with Crocodylus Park expert Grahame Webb telling NT News the prehistoric animals are highly resilient.

'They've been through plenty of dramatic changes in temperature and they've gone through that okay,' he said.

'I think its important to be careful with these doomsday predictions.'

SOURCE






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