Nature's Indomitable Spirit: New Zealand wilding pines, a reminder about the will to survive

Was just finishing a short opinion piece by Brian Taylor for New Zealand's Otago Daily Times about how best to deal with the wilding pines that spread throughout both the north and south islands. Wilding pines, also referred to as wilding conifers, are invasive species of pine trees, the result of a combination of early settlers stripping indigenous scrubland for agriculture and cattle grazing which provided a fertile base for various imported pine tree species to explode across the valleys and hillsides.

With New Zealand spending millions of dollars annually to try to stem the tide of the ever-expanding wilding pines, Taylor was questioning the wisdom of current strategies. Yes, the pines are an invasive species that is altering the natural landscape and the result is both an economic and environmental threat, but it's a result due in part to man providing the trees with the initial foothold. Taylor questioned whether current land management use - grazing and burning techniques to maintain economically important grasslands - would forever be at odds with wilding pines and whether there could be other natural buffers developed to help manage the pines' growth and expansion, rather than the felling of mature trees and removal of seedlings which has not yielded hoped for results.

Interesting article but what caught my attention most of all was Taylor's description of nature's tenacity, as it is applicable to all environments - land or sea, plant or animal.

"Mother Nature can be a rather intractable old matriarch, and no matter how strenuously Man tries to thwart her advances, she will invariably be the clear winner in a marathon. After all, she has been around far longer than mankind and has not survived millions of years by simply taking a back seat when threatened. She is a formidable contestant, smart, very smart in fact, versatile, highly adaptable, and loves a challenge. When the chips are down, she will always be one jump ahead, ever ready to override our mistaken endeavours by taking control of regeneration her way.

She abhors nudity and will make sure that all of her domain remains well covered. There will be no bare spots for her, no sir. Pull out a weed and see what she does, she will plant another one straight back and will continue to do so as long as we constantly annoy her by perpetuating our misguided attempts at laying the ground bare."

Taylor is describing nature's will to survive. Despite all that can be heaped upon it, whether through natural occurrences or man-made interference, nature will do what it can, do whatever is necessary to carry on. It will adjust; it will adapt. But what we must keep in mind is that to evolve and continue its existence, nature can make some cold, harsh decisions - such as extinctions if that's what it takes. And that can involve the loss of the smallest insect all the way up to the largest mammals in the sea. And it can include us just as easily. For all our accomplishments and all our self-importance, if we push nature too far, it can shake us off like a bad case of fleas.

After pondering whether New Zealand could adopt land management policies that work with nature rather than continually fighting it, Taylor closes with a thoughtful reminder about ecological perspective - in whose playground we are briefly being allowed to roam.

"We live in a mere moment of time in the history of the planet. It has constantly evolved throughout the ages, and will continue to do so long after we have gone. We are able to exist on earth only because nature provides us with all our needs for survival. Yet in this modern world of rapidly diminishing forest cover, some are still prepared to promote the age-old slash and burn mentality - in this case, 'for the good of the view, rather than for the good of the planet'.

Maybe it is time we reconfigured our response strategies and embraced greater biodiversity, which is, after all, the key to a balanced and healthy ecosystem."

Here, here.

Source: Otago Daily Times

Predators and Prey: study finds important changes in behavior from overfishing

When explaining the impact of commercial overfishing (or, for that matter, terrestrial hunting) on the predator-prey relationships in an ecosystem, conservationists will often talk in terms of changes in population of various species and it is often portrayed as a domino-like effect. This may make it easier for the layperson to understand - a singular, straight line chain of events - but scientists know that the reality of it is a lot more complex. They will speak in terms of a cascade effect, a bit like a nuclear chain reaction, where one event impacts several others, each impacting several others, and so on.

Because of that complexity, there is still a lot that we do not know as to what happens to an entire marine ecosystem when key predators are eliminated through overfishing. We have a tendency to look at just population numbers, but a recent paper in Ecology documented evidence of changes in prey foraging behavior and how this can have a pervasive effect across an entire reef system.

Researchers focused on the northern Line Islands in the South Pacific and studied the foraging behavior patterns of numerous species, using one pristine reef as a baseline for comparison to other areas that were impacted in various degrees by a loss of key predators through local fishing.

The predator-prey relationship is much more than "the big fish eats the little fish." Fundamentally, that may be true but there are also factors such as when and where prey forage that enter into the equation. Some animals maintain certain depth ranges or preferred areas around the reef, or they had particular times of day when they would venture out to feed - all offering a certain level of risk and effecting behavior designed to give them the best chance of survival.

The researchers in the Line Islands found that, with the loss of a predator, prey behavior changed over multiple species, and this, in essence, really upsets the applecart of ecological balance. In fact, the article proposed that, while there can certainly be changes in population numbers of various prey species (which can include predators of smaller species - remember, just about everybody is eating somebody else in the ocean), the changes in foraging behavior could be the more important issue with its effects rippling through the entire complex web of relationships that help to make up a healthy marine ecosystem.

We live in a very complex world, but we have a tendency to prefer our answers or solutions to be neat and simple. Unfortunately, nature hasn't successfully evolved over millions of years in a straight "A + B = C" fashion. With each day, scientists are learning more about that complexity and what profound effects we are having on it.

You can order the complete article from Ecology.