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Amazing Iceberg

Icebergs sometimes are lined. When glaciers flow, they can pick up and carry sediment with them and stretch it into long, thin bands formed where two glaciers meet (http://tmblr.co/Zyv2Js10MmSTx).

Those lines of dark ice can endure even when glaciers reach the sea – dark, sediment-rich layers alternating with cleaner, almost-pure ice layers.

This photo has the added beauty of the ice appearing deep blue, which occurs in very old ice that has most of the air squeezed out (http://tmblr.co/Zyv2Js15BxVJM). The white color in glaciers is produced by light bouncing off the edges of air bubbles included in the ice; when most of those have been compacted or squeezed out from being pushed to the bottom of a heavy glacier, the ice changes color and will appear this deep blue color when exposed.

Quick question...is the bird in front of the iceberg really there, or is that a reflection?

-JBB

Where do whales go when they die: Part Two

This is a continuation of the original "Where do whales go when they die?" post. If you have not read it yet, you can find it here: http://on.fb.me/1AtyZVr

The Effects of Whaling on Whale Fall Communities

When the effects of whaling are discussed, subjects that tend to be of concern are those whose changes can be easily tracked. These include, but are not limited to, changes such as habitat destruction, trophic cascade, exploitation, etc.. After the discovery of these whale fall communities by Smith and colleagues in 1987, marine biologists began to wonder how whaling has affected these deep-sea communities. But, because of how recently these communities were discovered, there is no data to compare current diversity and richness to those before whale exploitation. Between 1920 and 1986, over a million whales were hunted, resulting in the extinction of the Atlantic grey whale, and a 95% reduction in humpback whales. The biggest issue in regards to whale fall communities is that after around 1910, very few carcasses are released back into the water. Species that survive in whale fall communities will live and breed within the vicinity of the carcass. Individuals will breed and their offspring will leave the carcass to search for neighbouring whale falls, or, if the individual lives longer than the resources available, it too will leave in a search for new communities. Many of the scavenger species and chemoautotrophic species rely on whale falls being within a reachable distance of each other in order to survive. It has been assumed then, that those most reliant on whale falls have gone extinct, while the generalists have survived. Though no numbers can be definitively presented, researchers believe there could be a significant reduction in chemoautotrophs.

Whale fall communities and their role in deep-sea ecosystems is still a very new branch of marine biology. Though data is limited, the affects of whaling on deep-sea communities can be easily predicted. Whaling not only effects the environment in ways we can see, but in ecosystems that have only just come within our reach. This may be a good example for many other species as well; the relationships among species and the environment is very complex, it is difficult for humans to fully grasp what damage is done by our exploits.

~Rosie

Image credit: http://discovermagazine.com/2013/september/16-deep-sea-secrets

References and further reading: http://bit.ly/1HV5GA8