Tell me the old old story about wicked mankind and coral reefs

I have been hearing the story at the bottom of this post all my life (and I am now in my 70th year) but it has remained just theory.  At least global warming gets a rest this time, I suppose.

If someone measured agricultural runoff and correlated coral damage with it, I might believe it  -- but there are no such studies. And I think I know why.  At least a third of the Great Barrier Reef runs alongside Cape York Peninsula, which has no significant agriculture  -- and there are changes in the reef there too.

Note that the data for the study below was from one small island  -- while the reef is 1500 miles long!  They don't call it the "Great" barrier reef for nothing.  And Pelorus is actually a popular diving spot for coral reef exploration so is anything but  blighted!  I shouldn't laugh.

I wonder what Hoagy (Prof. Ove Hoegh-Guldberg), Australia's no.1 coral doomster, has got to say about this?  He seemed to fall into a depression for a couple of years when his own research showed that coral reefs bounce back rapidly from damage but he has started squeaking up again lately.  But his evasiveness shows what slime he is.

While I am talking about it, I might as well mention another recent bit of alarmism headed "Coral recovery may not herald the return of fishes on damaged coral reefs" by Bellwood et al.  That sounds pretty alarming, does it not?   In fact it's just Bellwood's attempt to ingratiate himself with the alarmists.   The paper is essentially a reprise of an earlier paper with some awkward findings.    Let me quote:

"We found no decrease in diversity, richness or abundance in reef fishes over the 12-year study period. Indeed, as in most previous studies,  the three main metrics, species richness, diversity (H0) and total abundance showed no response to a major disturbance (in this case the 1998 coral bleaching event).

So what gives? What Bellwood actually found was that a disturbance altered the *makeup* of the fish community.  Some species became relatively more abundant and other species less so. And overall there were MORE fish! Not quite what you might expect from his more recent heading! 

You have to feel rather sorry for scientists who are under such pressure to be "correct" but it is a pity that truth tends to get lost in the process

The influx of Europeans to Australia had a catastrophic effect on the Great Barrier Reef as far back as 90 years ago, before tourism and climate change made an impact, new research claims.

A study found that run-off of pesticides and fertiliser from farms near the Queensland coast clouded the waters of the reef, killing off its natural coral and drastically changing its ecology.

The change was disastrous for many of the animal species that lived in the reef, and for the nearby coastline since the native species had weakened the surf as it came crashing in from the Pacific Ocean.

The study, published yesterday in the Proceedings of the Royal Society, suggests that humans had disrupted the ecology of the Great Barrier Reef decades before climate change and reef tourism.

'There was a very significant shift in the coral community composition that was associated with the colonisation of Queensland,' study co-author John Pandolfi of the University of Queensland told LiveScience.

The European colonisation of Queensland began in the 1860s, with settlers hacking down forests to make space for farming. By the Twenties, rivers were pouring huge quantities of fertiliser and pesticides into the ocean.

To find out the impact that this early European colonisation had on the Great Barrier Reef, Professor Pandolfi's team drilled sediment cores 6.5 to 16.5ft deep into the reef off Pelorus Island, off the Queensland coast.

The professor told LiveScience that when coral dies, new coral sprouts on the skeletons and ocean sediments eventually bury them in place. The story of the reef can thus be reconstructed by dating the sediment layers.

The team found that for a millenium prior to the arrival of the European colonists, the reef was dominated by the massive, three-dimensional Acropora coral.

This species grows up to 16ft high and 65ft across, forming a labyrinthine network of nooks and crannies for marine life to inhabit, Professor Pandolfi said.  'They're like the big buildings in the city, they house a lot of the biodiversity,' he told LiveScience.

However, from the Twenties onwards, the impact of humans on the environment began to stifle the Acropora and sometime before the mid-Fifties it had stopped growing altogether - replaced by a slow-growing, spindly coral called Pavona.

The University of Queensland team believes that the polluted run-off from the new farms over time clouded the pristine waters off the coast, poisoning the native species. They also believe that same pollution fed an algae that smothered the native coral species' attempts to regenerate.

Several recent studies have shown that climate change and snorkellers have proved catastrophic for coral, with one finding that half the Great Barrier Reef has died off in the past 50 years.

But Professor Pandolfi and his colleagues' findings suggest that man has been damaging that reef and others for much longer than previously thought. The professor, however, says his work also suggests that the problem has a straightforward solution - reduce polluted run-off into the ocean.

'Any kind of measures that are going to improve the water quality should help those reefs to recover,' he added.

SOURCE