Mass extinction

This summer I had my first dive for 3 yrs due to an arm injury and was shocked how quickly the ocean around my house on Rakino Island has degraded. We dived on a scallop bed I have survived on for 12 years and didn't get a meal. Three divers were in the water for 60 mins and we saw 1 crayfish/ lobster where in the past we would see dozens of all sizes. 

On last year's NZ speaking tour of NZ with Professor Guy McPherson I spoke about how in 25 years of sailing I have watched our oceans die.

What's New

"We're not talking about a few dead fish littering your local beach. Mass die-offs are individual events that kill at least a billion animals, wipe out over 90 percent of a population, or destroy 700 million tons—the equivalent weight of roughly 1,900 Empire State Buildings—worth of animals."

This is an obvious extinction event. No osterich that ever put it's head in the sand survived, nor will we. At least we could face up to our fate if we were told the truth.

Mass Animal Die-Offs Are on the Rise, Killing Billions and Raising Questions

Huge animal die-offs, along with disease outbreaks and other population stressors, are happening more often

Long-spined sea urchins, which have nearly vanished from the Caribbean, march across a seabed.

National Geographic,

13 January, 2015

We're not talking about a few dead fish littering your local beach. Mass die-offs are individual events that kill at least a billion animals, wipe out over 90 percent of a population, or destroy 700 million tons—the equivalent weight of roughly 1,900 Empire State Buildings—worth of animals.

And according to new research, such die-offs are on the rise.

The study, published this week in the Proceedings of the National Academy of Sciences, is the first to examine whether mass die-offs have increased over time.

Researchers reviewed historical records of 727 mass die-offs from 1940 to 2012 and found that over that time, these events have become more common for birds, marine invertebrates, and fish. The numbers remained unchanged for mammals and decreased for amphibians and reptiles. (See "What's Killing Bottlenose Dolphins? Experts Discover Cause.")

Disease, human-caused disturbances, and biotoxins—like the red tides caused by algae that are prevalent along American coastlines—are three major culprits.

Why It Matters

Big die-offs can permanently change food webs. Ninety-nine percent of the sea urchin Diadema antillarum disappeared from the Caribbean in 1983 thanks to a pathogen. The herbivore's vanishing act paved the way for an algal invasion of reefs, smothering corals.

Massive die-offs can also endanger human activities like farming by disrupting insects that pollinate plants, like bees.

"Such events can reshape the ecological and evolutionary trajectories of life on Earth," the study authors write. (See "Why Are Millions of Starfish 'Melting'?")

The Big Picture

It's unclear what's making diseases more common or why red tides happen more often. Climate change and environmental degradation are some contenders.

Researchers also don't know why die-off rates differ between animal groups. The scientists may have missed some die-off events, giving the impression of steady or declining rates in mammals, amphibians, and reptiles. Or, these groups may not be as affected as fish, birds, and marine invertebrates.

What's Next

What's clear is that lack of coordinated attention from scientists is a problem, the study authors say. In fact, "at this time, the vast majority of [mass die-offs] are presented in newspapers," they write.

There needs to be better monitoring of these events, they say, since that's the only way we'll know how much trouble life on Earth is in.

Jeremy Jackson: Ocean Apocalypse