Is plant diversity on the skids? The scales of biodiversity loss

Paraguay2bImagine you want to monitor changes in plant diversity, to see whether diversity is increasing or decreasing over time. What spatial scale would you study?

Would you search for changes at the global scale, or at continental, regional or local scales? More importantly, would you expect to see the same trend or different trends if you examined changes at many scales?

At the global scale, biological diversity on Planet Earth is on the skids. Thousands of species face extinction and over a thousand hectares of forest are cleared every hour. Species diversity is falling because species are going extinct faster than new species can evolve. And we’re causing it.

At the continental scale, we see the opposite pattern. Continue reading

From Ballarat with love: Great biodiversity videos

Norm cartoonNothing on TV this weekend? Then watch a biodiversity video, or perhaps eight of them!

Last month the University of Ballarat hosted the excellent Biodiversity Across The Borders conference. Videos of many of the talks have just been posted on the University’s video site.

The opening speaker, Professor David Lindenmayer, kick-started the day with a fantastic talk on ‘Effective ecosystem restoration and management’. David’s talk includes many new findings from his group’s research on woodland restoration, and the video is a definite ‘must see’. I gave a talk on ‘Natural regeneration: connecting regional Australia’. An earlier blog contained a different version of the talk which I taped at home. This live, conference video includes a Google Earth ‘fly-over’ tour and loads of bad jokes, which weren’t in the earlier version. Continue reading

Rewilding Australia? A feral contemplation

I appreciate the irony, but huddled by the heater, I just read my first e-book on an iPad –  on how to better engage with nature.

Feral Monbiot cover


The book, Feral: Searching for Enchantment on the Frontiers of Rewilding, is a fascinating account of optimistic and dysfunctional approaches to nature conservation. The author, George Monbiot, argues that many conservation policies – especially in the UK – intentionally maintain impoverished ecosystems from the past, rather than creating diverse, dynamic ecosystems for the future. In their place, he advocates Rewilding. In his words,

… rewilding, unlike conservation, has no fixed objective: it is driven not by human management but by natural processes. There is no point at which it can be said to have arrived…. Rewilding… does not seek to control the natural world, to re-create a particular ecosystem or landscape, but – having brought back some of the missing species – to allow it to find its own way.

Feral is a fascinating and at times an irritating book. You can read many excerpts online (here, here, here and here), watch an animation of his main argument, view a TedTalk video, and see the author and opponents interviewed on BBC TV. If nothing more, Monbiot is a brilliant self-publicist, and he sells optimism really well. But PR aside, what does a book about conservation in Europe have to interest a reader in Australia? Continue reading

Natural regeneration: connecting regional Australia


Want to re-connect fragmented landscapes? Where would you start? With natural regeneration of course.

Natural regeneration of native trees and shrubs is abundant in many regions, where it provides valuable habitat and linkages between patches of native vegetation. Last week I gave a talk at the Biodiversity Across The Borders conference in Ballarat in a session on landscape connectivity, on behalf of my co-authors Lisa Smallbone and Alison Matthews. Our talk covered four topics.

  1. Why do we get extensive natural regeneration in some regions?
  2. Where do we find lots of natural regeneration in Victoria?
  3. How valuable is natural regeneration for birds?
  4. How can we incorporate natural regeneration in connectivity planning?

If  you didn’t get to last week’s conference, you can now watch the video of the talk, courtesy of YouTube.

Continue reading

Dense old trees: bitter and twisted ‘charismatic megaflora’

Suppressed trunk inverseWe all know an old paddock tree when we see one: broad, deep, canopy; sagging, tangled branches; broken boughs full of hollows. The classic woodland tree. But how do you recognize an old tree that grew – not in the open – but in a closed, dense stand? It won’t have a big, wide canopy nor a thick, wide trunk if its growth was suppressed by neighbors. Continue reading

Wetland quiz: answers revealed

2006 wetland closeupHow wrong can I be? I blithely predicted that last week’s quiz was far simpler than the previous one, but few readers guessed the correct answer. To re-cap, the question was: which species colonized the eastern side of Little Wallenjoe Swamp? Continue reading

Growback 6: A wetland quiz

canal & creek

It’s been a while since the last ecology quiz. This month’s puzzle should be a lot simpler than the last one.

A century ago, an irrigation channel, 100s of kilometers long, was built. The channel crossed many creek-lines, altering the natural flow patterns. In the photo above, two creeks run to the north (top). The creek on the left now banks up south of the channel, and a weir wall regulates flows to the north. The weir reduces flows along the creek and affects a string of intermittent wetlands further downstream. Continue reading