Image: Wikimedia Commons/Mikul
Canada's bird populations have a new predator: climate change.
According to "The State of Canada's Birds," the first comprehensive report on the state of Canadian avian species, Canadian bird populations have declined by an average of 12 percent since 1970. While some species are thriving, 44 percent of Canada's more than 460 bird species are losing numbers.
Grassland birds, migratory shorebirds and birds that eat insects in flight are in the steepest decline. Each of these groups has decreased by more than 40 percent and some individual species have decreased by more than 90 percent, such as the prairie-dwelling McCown's longspur, which is now considered to be "at risk."
Climate models predict that the Canadian prairies will experience increased drought, which could strip away habitat for waterfowl. Farther north, flooding and fires are expected to jeopardize bird populations in the Canadian boreal forest.
The early arrival of spring in recent years has also caused experts to worry that migratory birds will return to Canada after their food supply has peaked.
The problem of synchrony
"One of the concerns is ... that climate change is happening so fast it's throwing out of synchrony the food supply and the cycle of migration," said Ted Cheskey, manager of bird conservation programs at the nonprofit Nature Canada and an author of the report, led by the multistakeholder group the North American Bird Conservation Initiative.
Although they are still relatively common species, aerial insect feeders, like barn swallows and chimney swifts, have declined by 64 percent compared with previous levels. Some experts attribute the fall to a climate shift that has caused insect populations to peak earlier in the year, limiting what adults can feed their young.
Arctic bird species are also having a tough time. The Arctic is changing faster than anywhere in the world, and that could have significant impacts on nesting practices and the overall survival of Arctic birds, given changes in food availability, increases in the number of predators and more frequent severe weather events.
Climate change is already affecting Arctic ecosystems at a rate the authors say could outpace the ability of some bird species to adapt.
However, some bird populations are soaring. The snow goose population, for instance, has increased by more than 300 percent, although the birds are now degrading Canada's salt marshes. Overall, 33 percent of Canadian bird species have experienced growth since 1970.
Arctic shorebirds plummet
Of those under threat, shorebirds that nest in the Arctic have fared the worst. Overall, shorebird populations have dropped by 60 percent, and 10 species are in severe decline. Experts say the fall is largely due to the degradation of resting sites along winter migratory routes, spurred in part by climate change.
Only about 20 percent of Canada's bird population stays in the country year-round, which makes the preservation of avian habitat a continental issue, said Cheskey. Building bird populations back up to previous levels will require collaboration across national borders, he said.
The authors conclude that protecting areas vital to bird survival that are also most resistant to climate change will help reduce the harmful impacts of human activity on bird populations.
"We know birds are good indicators of overall ecosystem health, so we want to use protecting those bird populations as a means of protecting ecosystems for us, as well," said Cheskey. "We are all part of the same ecosystem."
A similar report on climate change and the state of bird species in the United States was published in 2010.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500.
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10 Comments
Add Comment"44 percent of Canada's more than 460 bird species are losing numbers."
Reply | Report Abuse | Link to thisWell duh! Statistics theory would predict that randomly 50% of species would lose numbers and 50% gain. 44% means that fewer species are losing numbers than should be expected.
PokerPlayer Says: Over the last 15 years there has been no statistically significant warming...
Reply | Report Abuse | Link to thisTrent Says: The 1980's were warmer than the 1970's. The 1990'were warner than the 1980's. The 2000's were warmer than the 1990's.
Here is NASA temperature graph that gives the lie to your assertion.
NASA Temperatures:
http://data.giss.nasa.gov/gistemp/graphs_v3/
Pokerplayer Says: ...did not match those predicted by the climate models.
Trent Says: Idiocy. You demonstrate a complete and utter lack of competence when discussing this issue. Climate models since Svante Arrhenius have predicted correctly:
1. That the Arctic would warm faster than anywhere else in the world.
2. Nights would warmer faster days.
3. Winter warms more than summer.
And that is just what the primitive pen and paper models from the 19th century predicted. All of the above phenomena and have been observed in the late 20th and early 21st century.
Later in the 20th century climate models predicted the following observations that:
1. The stratosphere would cool while the troposphere warms.
2. Storm tracks are pulled more pole ward.
3. That the Hadley Cells would expand.
Now you have been informed of all this many time before with links to the predictions and observation and yet you persist in falsely claiming otherwise. The only reasonable explanations for this otherwise utterly inexplicable behavior is that you are either incompetent or lying. So which is it?
Disagree? Then let us discuss using peer reviewed empirically based science why you disagree. Please provide a comprehensive science based explanation that explains ALL of the PREDICTED and OBSERVED phenomena listed above. If the models are inaccurate how it it that they got so much right? What empirically based predictions can you provide that will support your comprehensive alternative hypothesis?
Geo-Jelly-Brain Says: Well duh! Statistics theory would predict that randomly 50% of species would lose numbers and 50% gain. 44% means that fewer species are losing numbers than should be expected.
Reply | Report Abuse | Link to thisTrent Says: Tell me more about your expertise in wildlife population dynamics using science based sources please. I always amazed that so many fake skeptics are experts in EVERYTHING /s.
@Geo-Jelly-Brain,
Reply | Report Abuse | Link to thisSo that is a no then on providing a substantive response to your assertion? I am not surprised. When the going get tough the fake skeptics resort to distraction.
Anyone willing to bet that Geo-Jelly-Brain will never ever provide peer reviewed substantiating article on wildlife population studies? I thought not.
Thank you Trent1492 for fighting the good fight against the embarrassing ignorance (or well-compensated trolling) of climate change deniers. The science is settled-climate change is real, ongoing, destructive to most of the biosphere, and has the potential to get much, much worse. Anyone claiming otherwise either needs to rationally explain why nearly every climate scientist in the world (and all of their published research) is wrong or to reevaluate their mistaken position on this critical issue. I suspect that neither is likely to happen.
Reply | Report Abuse | Link to thisThanks Dylan for the kind words.
Reply | Report Abuse | Link to this"Climatewire and unScientific American "Seriously?
Reply | Report Abuse | Link to thisFreeper style comments have no business being in a fact based rational environment like here and braindamaged pun-y name calling should left in the kindergarden playground. We can't afford antropological climate change denial so let the trolls die of attention starvation.
Well said! To my knowledge, "geojellyroll" has never responded with any credible proof of any assertion he makes. He even seems incapable of participating in a rational discussion, let alone constructing a logical argument. I have my own theories about the psychology of such posters: that their only satisfaction is from seeing their views posted publicly.
Reply | Report Abuse | Link to thisIt is high time that those of us who prefer to engage in serious discussion should take back these comment pages. I have already hinted to SciAm that a moderator and some house rules are desperately needed, but so far to no avail. Personally, I would like to see revoked the commenting privileges of cranks and curmudgeons who persistently pollute these discussions with their utter garbage.
Geojellyroll,
Reply | Report Abuse | Link to this"Statistics Theory" would NOT "predict that randomly 50% of species would lose numbers and 50% gain" as you claimed.
You have somehow inferred that whether a species loses or gains population is a flip of a coin. Statistics is not a biological science. Nature determines if a species (or whatever biological classicafication -- in this case, the Class Aves (i.e. birds)) gains or loses population, not statistics.
What you said is analogous to having said that since the human species is gaining (or in the future could be losing) in population, then 50% of the races would lose numbers and 50% would gain numbers. Then claim that's due to statistics.
Your logic makes no sense. Hopefully, you will understand your error and apologize for your "Well duh!" insult to the author.
Pokerplayer, meteorology and climatology are two separate sciences. G - L - O - B - A - L.
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