12.10 Erosion Triggered by Earthquake and Tsunami
213
of experienced craftsmen. A change to locally sourced stone from varieties traded
before the tsunamis over considerable distances he attributes to the drowning of
coastal-dwelling canoe-builders and navigators.
There can be little doubt that the 1450 tsunamis had a devastating impact on
food resources with a consequent escalation of starvation and conflict over land and
resources. Losses of skills and expertise and knowledge are to be expected in any
society suffering severe demographic loss. Some population losses may well have
followed directly from the catastrophic earthquakes and tsunamis of the mid-15th
century but this alone is unable to account for major population decline in 15th
century New Zealand. There is skeletal evidence establishing low life-expectancy
and severe population decline covering the 600-year period from AD 1180 to AD
1769 to which the skeletons belong. This evidence will be studied in Chapter 14.
A 600-year demographic decline suggests the primacy of climate-driven population
losses undoubtedly amplified by losses through the nationwide tsunamis of AD 1220
and AD 1450.
How many would have been drowned in these tsunamis is unclear. The correlation between tectonic and volcanic activity and tsunamis must have been well known
to Maori. Amongst coastal tribes, recognizing signs of an impending tsunami must
have been part of traditional knowledge vital to survival. Maori dogs may well have
headed to high ground well ahead of a tsunami, as dogs in Japan do today, effectively giving a tsunami warning to coastal tribes. A ten-year-old English schoolgirl,
holidaying in Indonesia at the time of the 2004 tsunami, reputedly saved hundreds
of lives by recognizing the rapid retreat of the tide that precedes a tsunami and persuading people to leave the beach. A school project gave her the knowledge to save
herself and many others. Kevin Krajick [30] notes that while up to 300,000 people are thought to have died in the Indian Ocean tsunami of 2004, “the indigenous
seafaring Moken people of Thailand almost all survived. Their traditions warn that
when the tide recedes far and fast – as happens before a tsunami – a man-eating
wave is coming and everyone should run. They did.”
Passing on knowledge relevant to survival is of course one of the major
roles for tradition. Knowledge relating to impending earthquakes and tsunamis
must have been carefully preserved and transmitted in a country where recent
research estimates nationwide tsunamis can be expected to occur every 500
years [26].
It is easy to see how the devastating cumulative destruction of biota caused by
both wet erosion periods, the extreme cold of the Little Ice Age and by two tsunamis
in 1220 and 1450 with nationwide impact, would have created a demographic crisis
in Little Ice Age New Zealand. In the next chapter we draw on evidence relating to
Maori pa, derived both from early European accounts of pa and from modern field
archaeology, to establish that even in the richest areas there were massive population
losses in New Zealand during the Little Ice Age. In Chapter 14 we show through
statistical analysis of skeletal evidence that in the Little Ice Age the demographic
crisis faced in New Zealand was perhaps as extreme as that anywhere else in the
world.
213
of experienced craftsmen. A change to locally sourced stone from varieties traded
before the tsunamis over considerable distances he attributes to the drowning of
coastal-dwelling canoe-builders and navigators.
There can be little doubt that the 1450 tsunamis had a devastating impact on
food resources with a consequent escalation of starvation and conflict over land and
resources. Losses of skills and expertise and knowledge are to be expected in any
society suffering severe demographic loss. Some population losses may well have
followed directly from the catastrophic earthquakes and tsunamis of the mid-15th
century but this alone is unable to account for major population decline in 15th
century New Zealand. There is skeletal evidence establishing low life-expectancy
and severe population decline covering the 600-year period from AD 1180 to AD
1769 to which the skeletons belong. This evidence will be studied in Chapter 14.
A 600-year demographic decline suggests the primacy of climate-driven population
losses undoubtedly amplified by losses through the nationwide tsunamis of AD 1220
and AD 1450.
How many would have been drowned in these tsunamis is unclear. The correlation between tectonic and volcanic activity and tsunamis must have been well known
to Maori. Amongst coastal tribes, recognizing signs of an impending tsunami must
have been part of traditional knowledge vital to survival. Maori dogs may well have
headed to high ground well ahead of a tsunami, as dogs in Japan do today, effectively giving a tsunami warning to coastal tribes. A ten-year-old English schoolgirl,
holidaying in Indonesia at the time of the 2004 tsunami, reputedly saved hundreds
of lives by recognizing the rapid retreat of the tide that precedes a tsunami and persuading people to leave the beach. A school project gave her the knowledge to save
herself and many others. Kevin Krajick [30] notes that while up to 300,000 people are thought to have died in the Indian Ocean tsunami of 2004, “the indigenous
seafaring Moken people of Thailand almost all survived. Their traditions warn that
when the tide recedes far and fast – as happens before a tsunami – a man-eating
wave is coming and everyone should run. They did.”
Passing on knowledge relevant to survival is of course one of the major
roles for tradition. Knowledge relating to impending earthquakes and tsunamis
must have been carefully preserved and transmitted in a country where recent
research estimates nationwide tsunamis can be expected to occur every 500
years [26].
It is easy to see how the devastating cumulative destruction of biota caused by
both wet erosion periods, the extreme cold of the Little Ice Age and by two tsunamis
in 1220 and 1450 with nationwide impact, would have created a demographic crisis
in Little Ice Age New Zealand. In the next chapter we draw on evidence relating to
Maori pa, derived both from early European accounts of pa and from modern field
archaeology, to establish that even in the richest areas there were massive population
losses in New Zealand during the Little Ice Age. In Chapter 14 we show through
statistical analysis of skeletal evidence that in the Little Ice Age the demographic
crisis faced in New Zealand was perhaps as extreme as that anywhere else in the
world.