Canada geese fly in a 'V' formation to reduce their energy costs. Each bird is able to take advantage of the reduced wind resistance behind the lead birds. To avoid turbulence they fly at high altitudes.
Messages from Rotting Fish
Messages from Rotting Fish A 300 year old record left on lake bottoms in the
decomposing bodies of salmon is described today in the journal
"Science" by a team of Canadian and American scientists. It charts
the abundance of sockeye salmon back to 1700, the most complete
record yet. The sediments confirm for the first time that climate
and ocean conditions are potent natural forces driving salmon
numbers. There were dramatic swints-- associated with prolonged
cool and warm periods in salmon populations long before commercial
fishermen started hauling the fish out of the sea by the tonne.
That is not to deny that overfishing has had some very harmful
effects. The sediments reveal that a critical feedback loop in the
life cycle of salmon breaks down when too many fish end up in
fishermen's nets. In decades of heavy fishing the sediments
indicate a shortage of carcasses and shortage of nutrients and
zooplankton for young fish which has contributed to a long term
crash in salmon numbers. OCTOBER 27, 2000
Cool Articles
