Fabulous
Guest
Six years ago, Lesley Hughes published a paper blowing the whistle on what a fraction of a degree of warming was doing to the natural world. Now, with international scientists about to release a report anticipating temperature increases of three to five degrees in the next century, Dr Hughes is looking ahead to what will be required to rescue species.
Things like enlarging the national parks network or changing land-use patterns to allow plants and animals to move where they must to find conditions for survival as temperature and rainfall change. And even uprooting plants and animals from places where they no longer thrive and moving them somewhere they might have a chance.
"I think the single most important management strategy we can put in place is to connect up, or improve or reconnect, areas of habitat that have been fragmented," says Dr Hughes, a specialist on the impact of climate change at Sydney's Macquarie University. She is also a key contributor to the next report of the Intergovernmental Panel on Climate Change. The first section of the report, the most authoritative summary on the state of the planet yet produced, will be released in Paris on Friday.
"The next hurdle is to decide what to do about it. For me the bottom line is to stop species going extinct. So we need to focus on what we can do to improve opportunities for species to adapt."
One option for some species would be to move them to places where they might survive a strategy long employed to save big animals on the brink of extinction in such places as Africa. "A lot of ecologists and conservationists are very resistant to the notion of engineering the environment," Dr Hughes says. "In a perfect world we would not do it, but if the alternative is to lose a species, then we need to be broadminded enough to do that."
But it is a last-ditch option, and not desirable or even possible for most species, says Dr Hughes, particularly given that all species rely for their existence on other species in some way, and climate change is already eroding some of those relationships. She cites the example of oaks in the Netherlands now producing their spring leaves earlier. The caterpillar that feeds on those leaves is also coming out earlier to capitalise on the growth, but the bird that feeds the caterpillars to its young has yet to get the message. By the time the birds' young hatch, the food source is well past its peak.
In 2000, Dr Hughes published research in the journal Trends in Ecology and Evolution, which drew on a wide range of isolated data on various species bird migration rhythms, plant growth and shifts in habitat of creatures from butterflies to mammals and found the physiology, distribution and phenology (the timetable for budding, breeding etc) of species was already affected by the changing atmosphere.
"The most sobering thought is that even if only a fraction of the examples reviewed here are indeed a result of the enhanced greenhouse effect, they have occurred with warming levels at only one-fifth, or less, of those expected over the next century," the paper concluded.
In Australia, these changes have emerged from a warming of just 0.8 degrees recorded since 1910. "It doesn't sound like much, but temperature is used as a trigger in lots of events in species' life cycles like flowering or laying eggs or hatching," Dr Hughes says. "Fairly modest increases to temperature are already causing quite big advances in when things happen during the year. Spring comes earlier, lots of plants are flowering earlier, we've found lots of birds migrating to Australia earlier and leaving later, insects are hatching earlier. All those temperature-sensitive events are quickening up."
Dr Hughes was co-author, with Macquarie colleagues, of another report last year which found that Australian migratory birds were, like birds in Europe, arriving an average 3½ days earlier and leaving later.
"The take-home message is that small temperature changes have had big impacts," she says. "So translate that to what may happen in the next century, with maybe five or six times the warming we've already had, and our natural world will really change profoundly."
http://www.theage.com.au/news/natio...-species/2007/01/30/1169919337164.html?page=2
Things like enlarging the national parks network or changing land-use patterns to allow plants and animals to move where they must to find conditions for survival as temperature and rainfall change. And even uprooting plants and animals from places where they no longer thrive and moving them somewhere they might have a chance.
"I think the single most important management strategy we can put in place is to connect up, or improve or reconnect, areas of habitat that have been fragmented," says Dr Hughes, a specialist on the impact of climate change at Sydney's Macquarie University. She is also a key contributor to the next report of the Intergovernmental Panel on Climate Change. The first section of the report, the most authoritative summary on the state of the planet yet produced, will be released in Paris on Friday.
"The next hurdle is to decide what to do about it. For me the bottom line is to stop species going extinct. So we need to focus on what we can do to improve opportunities for species to adapt."
One option for some species would be to move them to places where they might survive a strategy long employed to save big animals on the brink of extinction in such places as Africa. "A lot of ecologists and conservationists are very resistant to the notion of engineering the environment," Dr Hughes says. "In a perfect world we would not do it, but if the alternative is to lose a species, then we need to be broadminded enough to do that."
But it is a last-ditch option, and not desirable or even possible for most species, says Dr Hughes, particularly given that all species rely for their existence on other species in some way, and climate change is already eroding some of those relationships. She cites the example of oaks in the Netherlands now producing their spring leaves earlier. The caterpillar that feeds on those leaves is also coming out earlier to capitalise on the growth, but the bird that feeds the caterpillars to its young has yet to get the message. By the time the birds' young hatch, the food source is well past its peak.
In 2000, Dr Hughes published research in the journal Trends in Ecology and Evolution, which drew on a wide range of isolated data on various species bird migration rhythms, plant growth and shifts in habitat of creatures from butterflies to mammals and found the physiology, distribution and phenology (the timetable for budding, breeding etc) of species was already affected by the changing atmosphere.
"The most sobering thought is that even if only a fraction of the examples reviewed here are indeed a result of the enhanced greenhouse effect, they have occurred with warming levels at only one-fifth, or less, of those expected over the next century," the paper concluded.
In Australia, these changes have emerged from a warming of just 0.8 degrees recorded since 1910. "It doesn't sound like much, but temperature is used as a trigger in lots of events in species' life cycles like flowering or laying eggs or hatching," Dr Hughes says. "Fairly modest increases to temperature are already causing quite big advances in when things happen during the year. Spring comes earlier, lots of plants are flowering earlier, we've found lots of birds migrating to Australia earlier and leaving later, insects are hatching earlier. All those temperature-sensitive events are quickening up."
Dr Hughes was co-author, with Macquarie colleagues, of another report last year which found that Australian migratory birds were, like birds in Europe, arriving an average 3½ days earlier and leaving later.
"The take-home message is that small temperature changes have had big impacts," she says. "So translate that to what may happen in the next century, with maybe five or six times the warming we've already had, and our natural world will really change profoundly."
http://www.theage.com.au/news/natio...-species/2007/01/30/1169919337164.html?page=2
