Saturday, December 12, 2009

drinking snow

Did you mother ever tell you not to drink snow? Well, apparently their mothers did not tell these birds… These hardy birds presumably don’t have to worry too much about lowering their body’s core temperature by taking a little snow, and if your diet is dry like seeds (or the fruit you’ve been eating is dry and shriveled) then a little water is very important to aid digestion...

Cedar Waxwing




Red Crossbill - female


Red Crossbill - male



Ruffed Grouse




These Red Crossbills and Ruffed Grouse are both drinking snow that has accumulated on a branch and has perhaps been compacted or melted a little and refrozen to ice, in which case it will have more water content that powdered snow…

Friday, December 4, 2009

Birds and climate change and, well, change...

There is an interesting little summary piece on the Birdlife International page today about the impact on birds of climate change. You can read this at: http://www.birdlife.org/news/news/2009/12/climate_impacts.html

Here in Manitoba, we have seen northward shifts in particular of aspen parkland species. For example, I recently documented Yellow-throated Vireo in the Porcupine Mountains, a good 200km north of even the most current range maps. In and around The Pas, where land clearing for agriculture has created parkland like habitat, other parkland species like Black-billed Cuckoo are starting to show up, again well north of their expected range. Trembling aspens themselves are apparently growing faster and are encroaching on new areas at a rapid rate.

Notice anything special about the bird in the photo below?


You might if you had been studying them in the U.K since the 1960s! This is Blackcap, a type of Old World warbler. Since the 1960s some Blackcaps breeding in Germany, began changing their migration. Instead of going southwest to Spain, they went northwest to southern England. There have been many articles written about that fascinating phenomenon. It is also one of those cases that demonstrate the important partnership between birdwatchers and scientists. It is precisely because there are so many birdwatchers in every corner of the British Isles that this phenomenon was so well documented. But the story doesn't end there...

We are also starting to learn of the truly staggering pace at which birds can react to seemingly subtle changes in their environment. An interesting piece came out in the Globe and Mail summarising the findings of a recent study demonstrating how the population of Blackcaps that migrate to the U.K have made subtle changes to their bill shape and wing shape in just a few decades. The authors concluded that this was thanks to the combined effects of climate change and… wait for it... bird feeders! Really makes one think of the impact of even seemingly innocuous behaviour like putting up a bird feeder. Read the following for more details: http://www.theglobeandmail.com/news/technology/science/british-birds-rapid-evolution-signals-human-impact/article1387804/

It is amazing what a difference a few degrees makes… and the cumulative pressures on birds from so much and so many types of change, change, change is staggering!

Tuesday, December 1, 2009

Another one on the wrong list!

With the announcement today of the latest round of COSEWIC (Committee On the Status of Endangered Wildlife in Canada) assessments, Manitoba has gained yet another bird on the wrong list – the list of threatened species. And, not surprisingly the newly listed species is a grassland bird – the grassland specialist being probably the most threatened group of birds by habitat, at least in North America.

The species in question is the Chestnut-collared Longspur, a species that breeds in our native prairie (in Canada in Alberta, Saskatchewan and Manitoba). The species has suffered severe population declines since the 1960’s. Like so many grassland birds, the Chestnut-collared Longspur is threatened by loss and fragmentation of native grasslands from the usual array of anthropogenic developments and their influences on the landscape.

More details on this new round of assessments can be found at http://www.cosewic.gc.ca/eng/sct0/index_e.cfm?#results

A few photos of the Chestnut-collared Longspur in community pastures with native hay in western Manitoba are included below. You can appreciate the rich colours of this well marked species but you will also notice in the first photo how the cryptic patterning on the back works well as camouflage in the grasslands. In the second and third photo you can see the elongated toes that gives the four species in the genus Calcarius their English name (longspurs). In Manitoba this species once bred as far east as Winnipeg, including at sites near the present day airport. Unfortunately, this species has not only declined in our province but also has experienced a dramatic collapse of the periphery of their range. These days, you need to go almost all the way to the Saskatchewan border to see one (at least to the Brandon area anyway). The same is true for other grassland specialists like Baird’s Sparrow, Burrowing Owl and Sprague’s Pipit. These birds are in urgent need of our assistance to try and win back the prairies that we are losing at such as alarming rate!