Tuesday, March 15, 2005

Bad News

Bythograea care of Peter Batson
ENN: Whaling Moratorium Likely to Be Dumped:
WELLINGTON, New Zealand — The 1986 international moratorium on commercial whaling is likely to be rescinded in the next few years, New Zealand's commissioner to the International Whaling Commission has warned.

Some whale species have recovered to levels were small harvests would not be harmful. Other species are still far below their historical population levels. I'm talking less than 1% of the level before industrialized whaling. The continued existence of whales in our oceans is a testament to the IWC's success, and it needs more time. This is a situation where endangered species protections can make a huge difference.

One interesting point about the effects of whaling is that the drop in population from their historical levels has had unknowable effects on the social structure of whale populations, and has almost surely changed the ecology of the oceans.

Think about it. We know whales are huge. Estimates from the Bering Sea indicate that there has been an 82% reduction in whale biomass in the last 200 years. Sperm whales went from being 74% of whale biomass to being 32%. It is estimated that there were 200-500,000 sperm whales in the North Pacific back then. Current estimates are around 15,000. A male sperm whale weighs ~27 tons (54,000 pounds or 24,500 kilograms). We aren't talking about a small change. These whales ate a lot, pooped a lot, and when they died, left a lot for scavengers.

That sounds trivial, but whale skeletons are one of the key sources of new organic material at the bottom of the ocean. Crabs and other mobile species at ocean vents use whale carcasses as fueling stations when they migrate between vent systems. Other than those carcasses, there's nothing to eat around there.

Fewer whales means fewer carcasses, which means less food for migrating deep sea species, which means they either die or fail to migrate. If they don't migrate, they don't get new genetic material, and inbreeding problems crop up. If predators and scavengers don't reach new vent systems, the ecology of these poorly understood ecosystems is changed.

The vent systems are cool for a couple reasons, and we covered them at the Evolution Project recently. Instead of deriving energy from sunlight and conversion of carbon dioxide and water to carbohydrates, there are bacteria at the vents which use hydrogen sulfide (H2S). This is a slight tweak on the system used by photosynthetic bacteria and algae. Since vent systems are similar to conditions where some believe life originated, those bacteria are very interesting.

A bunch of cool species have evolved to feed off of the bacteria, or even to have symbiotic relationships with them. By understanding those ecosystems we better understand the origins of life, as well as adaptations which may help us grow food in space. Plus, these animals and bacteria are simply amazing. They are just fascinating places.

It would be a shame if New Zealand and Japan's hunger for whale meat were to harm these amazing outposts of life.

Stay Hungry” by Talking Heads from the album More Songs About Buildings And Food(1978, 2:40).