May 27, 2009

Ocean life in olden days is detailed

Census of Marine Life historians meeting in Vancouver, Canada, say they have reconstructed images of past sea life that boggle the imagination.

The researchers said they used such sources as old ship logs, literary texts and tax records to reconstruct what life in the ocean was like prior to the early 1800s.

Before oil hunters harpooned whales by the hundreds, the ocean around New Zealand teemed with about 27,000 southern right whales - roughly 30 times as many as today, the scientists said.

And about the same time, U.K. researchers say large pods of blue whales and orcas, blue sharks and thresher sharks darkened the waters off Cornwall, England, herds of harbor porpoise pursued fish upriver and dolphins regularly played in inland waters.

Researchers James Barrett and Jen Harland of Cambridge University, Cluny Johnstone of York University and Mike Richards from the Max Planck Institute in Germany say a shift from eating locally-caught freshwater species to marine fish species occurred about the year 1000.

Maria Lucia De Nicolò of the University of Bologna said the real revolution in marine fishing occurred during the mid-1600s when pairs of boats began dragging nets.

The reconstructions of ocean life in olden days is being presented in Vancouver this week during a Census of Marine Life meeting, part of the second Oceans Past conference.