New Zealand's forest area has declined by 65% and wetland areas by 85% since human settlement. Photo / Getty Images
As a kid I loved dinosaurs. I still have the book my parents bought, featuring vivid pictures and exciting descriptions.
The coolest part was a timeline, running across the bottom of each page. Over 100 million years, the creatures became more diverse, exciting and extraordinary. And then, on the last page, it all stopped. The dinosaurs, along with many other creatures and plants on earth, were gone.
The finger of suspicion has been pointed at an asteroid impact, large enough to cause a sudden and cataclysmic change to earth's climate and resulting in the fifth mass extinction. Many plants and animals perished and it took millions of years for life on earth to recover.
It is happening again. Species are dying out across the globe at a frightening pace, far in excess of the normal rate; some say 10,000 times faster.
The latest news comes from a study by the Stanford Woods Institute for the Environment last month, but Google 'Mass Extinction' and you'll find a slew of references going back many years.
"A whole range of really broad global drivers are causing quite a lot of disruption," says Andrea Byrom - director of the Biological Heritage National Science Challenge. "That includes land use intensification, climate change, invasive species, nitrous oxide pollution and degrading water quality."
This time, we humans are to blame.
"Human-induced climate change is happening, no doubt about that, and all life on earth will be affected. The unsustainable and inequitable loss of biological diversity, over the last 45 years, is of much greater significance than climate change," says Ian Spellerberg, Emeritus Professor of Nature Conservation at Lincoln University.
"So mass extinctions is just a very small part of the ongoing loss of diversity in nature."
Why is biodiversity so important for New Zealand?
"Pollination, soil fertility, variety and quantity of food, water and air quality is in serious trouble," Spellerberg comments. "The status of our fauna and flora is being eroded, especially plant species. Polluted streams can have a high organic load and only a few species can tolerate that." Other organisms will be gone from the stream, taking their biodiversity with them.
He sees biodiversity as a measure of nature's health, with forestry and agriculture dependent on genetic diversity.
Byrom agrees. Locally, species may provide medicines that we haven't discovered, and 'ecosystem services' such as flowers for pollination. "They are keeping our critical life-supporting systems ticking over."
Biodiversity provides climate stability, disease-control, cultural diversity, environmental knowledge, food-chain stability and oxygen too. This is the message from Stewart Brand, president of the Long Now Foundation, co-founder of the Revive and Restore project in San Francisco and admirer of New Zealand's efforts in island conservation.
"Here in New Zealand DoC [the Department of Conservation] do an extraordinarily wonderful job. We are often leading the way in terms of dealing with invasive species, biosecurity, island refuges," adds Spellerberg.
Pest eradication on Great Mercury Island off the Coromandel coast has supported long-term success for native geckos, giant tusked weta, tuatara, kaka, kakariki, New Zealand dotterel, taiko (petrels) and other sea birds, as well as 50 native land snail species.
DoC's Te Maruia Waka Huia programme is protecting native biodiversity in the Maruia Valley beech forest in South Island. As well as possum, rat and stoat control, feral goats and invasive weeds are tackled. Pest numbers have dropped dramatically and native species such as the whio (blue duck) are recovering.
"The state of nature has declined over the last 45 years, despite the growth in resources and organisations trying to conserve nature," says Spellerberg. He, like Byrom, would like to see more support for DoC.
Spellerberg also believes lack of awareness is an issue and more information is needed. For example, he would like to see regular state of the environment measures, just like weather and stock market reports.
Awareness of what is a native plant and what is a weed may be about to receive a helping hand. With funding from WWF NZ, a team at the University of Otago are working on a development of their Flora Finder smartphone app that will let you identify invasive weeds and even tell you how to deal with them.
However Byrom thinks more action is needed. "It requires policy interventions. As you can see with our ability to deal with climate change, we're not doing very well. The Government doesn't sign up to things that have teeth. We need to be more explicitly balancing economic drivers with environmental drivers, building the environmental side of the balance sheet a lot more."
You don't have to leave it to others. DoC has resources on their web site that can help you build a weta hotel, attract birds and lizards to your garden, track pests and even make your cat conservation friendly.
The scientists agree, humans are the asteroid. How much of an impact we make, depends on us.
Mass extinction refers to an extinction affecting a great many different groups of organisms occupying diverse and wide-spread environments.
Scientists agree that we are now entering a period of mass extinction - the sixth in the world's history. The fifth wiped out the dinosaurs, along with more than half of the species on earth, 65 million years ago.
Loss of biodiversity is even more important than total extinction - biodiversity is a measure of nature's health. The loss of an organism from a local ecosystem can have a significant damaging effect, even if that organism is still able to survive elsewhere on earth.
New Zealand's forest area has declined by 65% and wetland areas by 85% since human settlement about 700-800 years ago. On the lowlands of the Canterbury Plains, for example, less than 0.5% of the plains still support native vegetation.
Biodiversity is important for soils, waterways and the sea, as well as forests, wetlands and mountain areas. Many organisms depend on each other in a local ecosystem. Healthy soils and waterway are needed for agriculture. We could lose the soils we need to grow crops, the natural predators that control pests, and the pollinators that are needed for the survival of flowering plants (including fruit trees) if our native biodiversity is harmed.
NZ has a good international reputation for protection of our environment - for example island habitats and pest eradication.
DoC has had a number of successful conservation programmes; pest-free islands, the battle for our birds, conservation services programmes, robins return project and others. Some say DoC could do more with increased funding.
The Government has announced a funding programme to conserve the kiwi, aiming for a 2% increase in numbers instead of a 2% decline. This not only helps the kiwi, a much-loved national icon, the programme is likely to have benefits for the local habitats where kiwi live; a collateral benefit to the ecosystem
Currently information and key statistics that indicate the natural health of the NZ environment is collected independently by individual organisations. The Environmental Reporting Bill is going through Parliament and will provide for the collation and publication of this in one forum, but there is concern about political interference
You can help. Find out more through bodies such as DoC, the National Wetland Trust, WWF NZ, New Zealand Plant Conservation Network, Forest & Bird or your local conservation groups.
DoC has resources on what you can do as an individual; including activities that are literally in your own back yard. Check out bit.ly/1eUfIYV
Know your enemy. A new app is coming that will help you identify invasive weeds and tell you what to do with them
The Environmental Defence Society, an organisation focused on resource management professionals is running a Conference - Wild Things: addressing terrestrial, freshwater and marine biodiversity loss. 12-13 August, Auckland; Check out edsconference.com
This global challenge series has been made possible with support from Lincoln University. Lincoln University is among our more progressive on these issues, with three overarching organisational goals; to feed the world; protect the future; and live well. It's with these three goals in mind that every Lincoln course is now designed, and first and second-year students are required to undertake courses in understanding global challenges and the opportunities that lie in solving them.
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Treatment has been limited to psychiatrists and paediatricians until now.