Rodents — they love climate change
Rats and mice have been our unwelcome travelling companions for many centuries. Wherever we humans have migrated on our evolutionary journey, these adaptable little rodents have migrated with us.
They have shared our houses, food and even our beds. In turn, we have trapped, shot, poisoned and even eaten them in their millions but they are still with us changing their lifestyles and populating our modern homes, towns and cities with impunity.
This year they have appeared in greater numbers in Waikato and other regions than we have seen for many years.
In native forests, these regular rat and mice plagues are associated with mast years; the years when some trees produce large numbers of seeds, providing a greater than usual food supply.
As a result, rodent numbers explode. This year, however, is not a mast year. So what has created the significant increase in rodent numbers?
The answer may be in dramatic changes to weather patterns.
Last September was the wettest for many years – Hamilton Airport measured
1271mm of rain since the beginning of the year, which is the highest January-to-September tally since records began in
1935.
This year is already on the way to being the wettest in more than 80 years, with bigger floods and heavier downpours throughout most of the country than ever before.
The year before, 2016 was also the hottest year ever recorded at the Earth’s surface and this year temperatures have been almost as high.
Hot, moist conditions are ideal for rodent survival, with lots of feed production through the months when usual shortages create a natural mortality.
Could it be that, like the recent dramatic weather bombs which have devastated many parts of the country, rat and mouse plagues are result of equally dramatic changes in the world’s climate?
The debate about climate change, or global warming as some call it, has created more ill-informed argument, pseudoscience, superstition and ignorant comment than almost any other subject in recent years.
Reliable science tells us that the world’s climate has been changing for countless millions of years. That science also shows that, until the development of civilised human society and technology, most of those changes occurred over hundreds of thousands of years.
Archaeologists tell us that, on the few occasions when the world’s climate and temperature changed suddenly, the impact on some life forms was catastrophic.
Those species which could not adapt fast enough disappeared into extinction.
About 50 years ago, scientists predicted that the increase in carbon dioxide in the atmosphere, as a direct result of the combustion of coal and oil over a relatively short 200 years, would cause global warming.
The amount of carbon in the world has not changed, but most of it was locked up in fossil fuels.
Since the start of the Industrial Revolution just over 200 years ago and the invention of the internal combustion engine a little more than 100 years ago, we have dug up and burnt countless billions of tons of coal and oil, releasing all that stored carbon dioxide into the atmosphere at an ever-increasing rate.
Lead author of a new study on climate change Dr Lijing Cheng recently discovered that sea surface temperatures are increasing rapidly, which is affecting weather and climate through more intense rains and rising land surface temperatures.
The new research has quantified how much the Earth has warmed over the past 56 years due principally to human activity and the combustion of fossil fuels.
That has taken carbon, in the form of coal and oil, and added it in the form of carbon dioxide to the atmosphere at everincreasing rates. That increase of more than 40 per cent, with most since 1980, has trapped heat in the Earth’s system, warming the entire planet to the point where it can now be reliably measured.
Most governments throughout the world accept that there is a problem and that something needs to be done, but they have done nothing but talk, simply because too many influential people refuse to accept that there is a problem at all.
Many still claim that climate change is all a big hoax, in spite of measurable and dramatic weather changes and rising sea levels.
Will they still be claiming that when we are launching the lifeboats?
Planet Earth is possibly not at risk from climate change, but human life as we know it probably is, simply because we are collectively too stupid to adapt as readily as the rats and mice which plague us.