Migratory Birds Struggle to Adapt to New Climate
It’s a sad fact that climate change has already begun in earnest, and will continue for some time even after we shut down the fossil-fuel machine. Though turning off the tap to minimize the damage is still a first priority, we need to face the likelihood that we’re going to be living in a new world no matter what we do. A number of studies that have come out this past week focus on the way birds, insects, plants and freshwater fish are adapting.
A Swedish survey of 20 years of data on migratory birds suggests that European species have been adapting to warmer temperatures, but not enough. Set temperatures are approximately 250 km more to the north than at the beginning of this period. What this means is that since average temperatures for a particular time of year are warmer throughout the continent, migratory routes should also adjust. Specifically, each species should be shortening its trips south during the winter, and spending their summers farther north than previously.
But what the Swedish group has discovered is that, although bird species have been moving northwards, they haven’t been adjusting their routes as quickly as the climate itself has been changing. In fact, they’ve only adjusted their wintering and summering spots by half the distance they should have in order to maintain the same living temperatures. The danger is that the health of the birds will be badly affected if they don’t learn to move to a better temperature range for their physical needs.
The group also looked at butterfly migration patterns, and found them to be out of sync with the birds. Since caterpillars and butterflies are a food source, this is also likely to have deleterious effects on both bird and insect species. It’s not a stretch from there to consider a domino effect, where caterpillar/butterfly populations get out of control, plants are damaged, other animals relying on those plants starve, etc.
On Canada’s West Coast, scientists are working on a long-term study on how plant life on British Columbia’s Mt. Arrowsmith is affected by climate change. The project originally began in 2006 and was supposed to have surveys every five years, but the 2011 survey was delayed due to lack of funding. Instead, the first report will be in 2016, and will likely show more dramatic changes as a result of the greater lapse in time.
Temperature sensors have been replaced and data has been collected, but the survey of the plants themselves are still a few years away. However, none of the data will go to waste, they assure us. The ecological insights will surely be invaluable, all the more so in that the data cannot be collected quickly.
Lastly, UK scientists working in Iceland have discovered that the effects of climate change may be very similar across a broad number of ecosystems. By comparing otherwise identical geo-thermally heated streams, they were able to measure the effects of varying temperature in otherwise identical ecosystems.
They discovered that carbon respiration varied predictably with temperature changes. They suspect this will hold whatever the particular combination of species. Thus, existing aquatic ecosystems where the organisms resident do not change, will likely be affected the same way metabolically by an increase in temperature. This will likely have other effects on the eco-dynamics of the species in turn.
Photo credit: Ken Thomas