wild places | wild happenings | wild news
make a difference for our wild places

home | links | search the site
  all articles latest | past | articles by topics | search wildnews
wild news on wildsingapore
  The Herald 28 Jul 06
How global warming has thrown nature into disarray
Alan MacDermid
Thanks to alert from Joseph Chun

SCOTLAND'S wildlife food chains are being thrown out of sync by global warming, putting thousands of creatures at risk of starvation, scientists warned yesterday.

A new study shows that animals and plants are responding to climate change, but some more rapidly than others. The result could be a disastrously late lunch for fish species ultimately dependent on the the most basic plankton at the bottom of the chain.

The disturbing findings appear in a new report prepared by the Centre for Ecology and Hydrology and published by Scottish Natural Heritage.

CEH investigators found that of more than 500 spring and summer biological events, such as wild birds laying eggs, emergence of aphids or butterflies, and flowering of plants, 74% show some evidence of being earlier. A quarter of the total were significantly earlier and only three per cent were significantly later.

The authors warn that the different rates of change in species could mean that food chains may become out of balance or "de-synchronised". The report states: "Some species will inevitably suffer from these changes, whilst some others will benefit."

Aphids appear to be particularly responsive to climate change, as scientists are now first catching them on average 16 days earlier than at the start of a 34-year period of recording.

The seasonal cycles of many types of marine plankton, the food for many other species in the sea, are also becoming earlier, with one particular species advancing its seasonal peak nearly four weeks since the 1950s. Yet diatoms, a particular group of plankton which are the bases of the marine food chain, have been slower to react.

Tim Sparks, one of the authors of the report, said: "This could be very important because it may eventually lead to certain groups that are dependent on diatoms, missing the main pulse of food. This could have a knock-on effect on species higher up the food chain, such as commercially important fish species."

Professor Colin Galbraith, director of scientific and advisory services at SNH said: "This is the most comprehensive report yet on the timing of biological events related to climate change in Scotland. If we needed any more proof that climate change is a reality then it is contained within these pages.

"These results show that species are responding at different rates to the effects of warming temperatures on land, air, freshwater and sea, and this could ultimately mean that timings of natural events will become so out of balance as to affect food webs and competition between species. The challenge now is to develop conservation plans which will help vulnerable species adapt to these continuing changes here in Scotland, as well as supporting ongoing international initiatives to reduce carbon emissions."

The report, Natural Heritage Trends of Scotland: Phenological Indicators of Climate Change, which was produced for SNH by the CEH shows that: Butterflies were arriving 7.6 days earlier over a 28 years of monitoring, but moths advanced by an average 5.1 days over a 31-year period. Birds were on average nesting four days earlier than 38 years ago, but some have shown stronger trends than others – for example, records of the first eggs laid by dippers (small birds found feeding and nesting along rivers) in Scotland, have advanced by about nine days.

These changes appear to be linked to temperature rises in the environment.

Phenology, the study of regular events in nature's calendar, is one of the most accurate indicators of climate change, as biological events happen every year at around the same time.

links
Related articles on Wild shores and Global warming
about the site | email ria
  News articles are reproduced for non-profit educational purposes.
 

website©ria tan 2003 www.wildsingapore.com