Saturday, January 17, 2015

Marine Extinctions - Paper!

Click for detail!


In brief, they postulated that compared to the terrestrial biota, there had been comparatively few - and that after having had a closer look at two controversial species, I could find zero evidence for any marine Fishes that had gone extinct during the anthropocene.
But obviously there has been a grave reduction in numbers all the way to local extinctions, meaning that many populations are now so severely depleted that they have accumulated extinction debt; and having thus lost much of their resilience and faculty to adapt, an environmental catastrophe like Climate Change could well push them over the brink.

And now this is largely being confirmed in this paper.
Synopsis here.
And I cite.

On many levels, defaunation in the oceans has, to date, been less severe than defaunation on land.
Developing this contrast is useful because our more advanced terrestrial defaunation experience can serve as a harbinger for the possible future of marine defaunation (3). Humans have had profoundly deleterious impacts on marine animal populations, but there is still time and there exist mechanisms to avert the kinds of defaunation disasters observed on land. Few marine extinctions have occurred; many subtidal marine habitats are today less developed, less polluted, and more wild than their terrestrial counterparts; global body size distributions of extant marine animal species have been mostly unchanged in the oceans; and many marine fauna have not yet experienced range contractions as severe as those observed on land.

We are not necessarily doomed to helplessly recapitulate the defaunation processes observed on land in the oceans: intensifying marine hunting until it becomes untenable and then embarking on an era of large-scale marine habitat modification. However, if these actions move forward in tandem, we may finally trigger a wave of marine extinctions of the same intensity as that observed on land. Efforts to slow climate change, rebuild affected animal populations, and intelligently engage the coming wave of new marine development activities will all help to change the present course of marine defaunation. We must play catch-up in the realm of marine protected area establishment, tailoring them to be operational in our changing oceans. We must also carefully construct marine spatial management plans for the vast regions in between these areas to help ensure that marine mining, energy development, and intensive aquaculture take important marine wildlife habitats into consideration, not vice versa. All of this is a tall order, but the oceans remain relatively full of the raw faunal ingredients and still contain a sufficient degree of resilient capacity so that the goal of reversing the current crisis of marine defaunation remains within reach. 

The next several decades will be those in which we choose the fate of the future of marine wildlife.
Indeed, there is hope.
And like I said back then, there is a role, small or big, that each of us can play in order to ensure that the worst case scenario does not eventuate.

And what about the Sharks?
Re-read this report by the IUCN and this paper by Christine!

Let' do it!

H/T The Ambassador aka the Saffron Pimpernel!

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