[Coral-List] global threats drive coral declines of world reefs, not local impacts

[Douglas Fenner]

       I just discovered this article.  They found that coral cover does
not correlate with local human populations, a proxy for local human
impacts.  That implies that world coral declines are primarily driven by
global threats, not local threats.  There are obvious local impacts on
corals that we do need to address, of course, the evidence of that is
abundant.  But for the world's corals as a whole, not only is global
warming crucial to reduce, but it is nearly the whole ball game.  The
results for macroalgae are similar, there is a statistically significant
effect on both by population due to the large sample size, but for both, it
is tiny and so ecologically unimportant.

They point out that it is very different with reef fish, local
human effects are the dominant impacts on reef fish populations, with loads
of evidence it correlates with distance from humans, distance to large
markets, closed vs open fishing areas, etc.  And of course, loss of coral
and rugosity also reduces fish.  So the results of this study are specific
to corals and macroalgae and largely don't extend to fish.

 Bruno, J.F. and Valdivia, A. 2016. Coral reef degradation is not
correlated with local human population density. Scientific Reports 6:
29778, 7pp.

https://www.nature.com/articles/srep29778      open-access


Cheers, Doug

-- 
Douglas Fenner
Lynker Technologies, LLC, Contractor
NOAA Fisheries Service
Pacific Islands Regional Office
Honolulu
and:
Coral Reef Consulting
PO Box 997390
Pago Pago, American Samoa 96799-6298  USA

Costanza, R. 2023. To build a better world, stop chasing economic growth.
Nature 624: 519-521.   https://www.nature.com/articles/d41586-023-04029-8

Fossil fuel air pollution kills 5 million people world-wide per year
https://www.yahoo.com/news/research-shows-disturbing-between-millions-200000257.html

World's richest 1% emit as much as 5 billion people
https://makerichpolluterspay.org/climate-equality-report/

Huge expansion of fossil fuels planned, will be very destructive
https://www.theguardian.com/environment/2023/nov/08/insanity-petrostates-planning-huge-expansion-of-fossil-fuels-says-un-report

"without policy changes, the world will heat up enough by the end of the
century that more than 2 billion people will live in life-threatening hot
climates"         Will you be in that area???
https://www.yahoo.com/news/scientists-sounding-alarm-dangerous-problem-123000792.html

World subsidies for fossil fuels reached an all-time high of over $1
TRILLION in 2022, the last year for which data is available.  The subsidies
MUST end.

https://blogs.scientificamerican.com/observations/fossil-fuel-subsidies-must-end/