Atlantic Ocean. The earliest document to mention the use of whale oil
or blubber by the Basques dates from 670. In 1059, whalers from
Lapurdi are recorded to have presented the oil of the first whale they
captured to the viscount. Apparently the Basques were averse to the
taste of whale meat themselves, but did successful business selling
it, and the blubber, to the French, Castilians and Flemings. Basque
whalers used longboats or traineras which they rowed in the vicinity
of the coast or from a larger ship.
Study unlocks history of the seas
By Mark Kinver
Science and environment reporter, BBC News
Medieval fishermen first took to the open seas in about AD1,000 as a
result of a sharp decline in large freshwater fish, scientists have
suggested.
They say the decline was probably the result of rising population and
pollution levels.
The study forms part of a series that examines the impact of humans on
life beneath the waves throughout history.
The findings will be presented at a Census of Marine Life (CoML)
conference in Canada, which begins on Tuesday.
"Fish bones are found in archaeological sites... all around the north-
western part of Europe," said co-author James Barrett, from Cambridge
University's McDonald Institute for Archaeological Research.
"What we have done is to start to piece together some of the
information that has been gathered."
This involved looking at the fish bones to determine what species they
came from, and from what time period.
“ One of the straightforward hypotheses is that freshwater fish were
no longer sufficient to satisfy demand ”
Dr James Barratt, University of Cambridge
Dr Barrett observed: "At the end of the first millennium AD there is
this wholesale shift in emphasis from reliance on freshwater fish
towards marine species."
"It is not rocket science, it is just literally looking at the
proportion of species that are obligatory freshwater ones, such as
pike... and which ones are obligatory sea fish, such as cod and
herring."
As for understanding what caused the shift, Dr Barratt said that it
would be inappropriate to attempt to identify a single cause.
"But when you look very carefully at the freshwater fish bones from
the York site, where a big collection was gathered, you can see that
the length of the fish are decreasing through time," he told BBC News.
"Certainly, one of the straightforward hypotheses is that freshwater
fish were no longer sufficient to satisfy demand.
"This was likely to have been for two reasons; one was because there
had been a reduction in the availability of freshwater fish as a
result of overfishing, or from things such as people building dams for
water mills.
"The second thing would have been that there would have simply been
more people."
Dr Barrett added that around this period there was a rapid expansion
of towns and cities in north-western Europe.
"So this meant that there was an increased pressure on freshwater
fish, and there was an increase in demand that probably could not have
been satisfied even if the supply had remained stable."
Dr Barrett's team's study will be one of a number of research projects
that formed part of the CoML's History of Marine Animal Populations
(HMAP).
The project aims to address a number of questions, including how the
diversity and distribution of marine animals have changed over the
past 2,000 years, and what factors forced or influenced these changes.
Professor Poul Holm, the global chairman of the HMAP project, said
that the history of marine animals had been one of the great unknowns.
But recent scientific advances was allowing researchers to gain a
better understanding, he added.
"We now know that the distribution and abundance of marine animal
populations change dramatically over time," he explained.
"Climate and humanity forces changes and while few marine species have
gone extinct, entire marine ecosystems have been depleted beyond
recovery.
"Understanding historical patterns of resources exploitation and
identifying what has actually been lost in the habitat is essential to
develop and implement recovery plans for depleted marine ecosystems."
Many of the findings by HMAP researchers will be presented at the
Oceans Past II Conference, which is begins on Tuesday at the
University of British Columbia, Vancouver, Canada.
COML, which began back in 2000, is an international research programme
involving thousands of scientists from around the world.
The goal of the decade-long endeavour is to assess and explain the
diversity, distribution and abundance of marine life in the world's
seas and oceans.
The publication of the first complete global Census of Marine Life is
scheduled for October 2010.
Story from BBC NEWS:On BBC
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