American Barn Owl in Vancouver

One of the highlights of my recent visit to Vancouver for the International Ornithological Congress and the COSEWIC (Committee On the Status of Endangered Wildlife in Canada) Bird Specialist Subcommittee meeting was seeing 10 Barn Owls. My international friends may be surprised by this because Barn Owls are common globally, and American Barn Owls are also common on this continent. Most of Canada, however, is beyond the range of the species. The only two areas where Barn Owls occur regularly in Canada are in southern Ontario (the eastern population is almost extirpated and listed as Endangered in Canada) and southwest British Columbia (listed as Threatened in Canada).  This magnificent Barn Owl (three photos below) on a day roost (presumably a female based on colouration and the size and extent of spotting), glowing red in the smoky air wafting over the city from northern forest fires, left a lasting impression on the whole committee. Note how powerful the talons of these owls, so useful is dispatching large rodents, are:

(American) Barn Owl (Tyto alba pratincola OR Tyto furcata pratincola), British Columbia, Canada, © Christian Artuso.

Northern Hawk Owls (Surnia ulula) and their young

Northern Hawk Owl (Surnia ulula), adults and fledglings, Manitoba, Canada, © Christian Artuso.

Although the Northern Hawk Owl is a common species in Manitoba and I have seen as many as 43 in a single day, it is not all that often that I get to enjoy watching a family interact. The past two years though have brought great opportunities to observe pairs with 2 – 4 young. 

Here are two photos of one of the breeding pairs, hunting to bring food for their young. This pair brought in two voles in less than 15 minutes during this observation. As the second photo shows, they are not too proud to perch on wires if these provide a good vantage over a prey-rich meadow. They are also mostly diurnal (these photos in the early morning).

 

And here are the two youngsters this pair was feeding (another pair recently had four hungry mouths to feed).  You can see that they are quite well developed but they still sport a little down on teh top of the head.

A better look at each of the two youngsters as they shuffled perches (photos are taken from a distance and heavily cropped)

I got lucky to catch this youngster in mid call, not long after it had been fed a vole (I was not quick enough to photograph the prey delivery, which was over with in a matter of seconds).

And here are two photos of a youngster taking off when the adult came in with a vole. One short call from the adults and the youngster flew approximately 50 m to an open perch where the prey was delivered.

Another Northern Hawk Owl in a different location was observed in an interesting behaviour, flicking its tail up and down. There were small passerines in the area and this seemed to incite mobbing behaviour. 

 Enjoy!

Owls and vehicles

Slow down, you move too fast...

Owls fly low and slow. They have evolved that way over millions of years and it serves them well for hunting. Their adaptations for silent flight not only offer them stealth, they also allow them to use their exceptional hearing in mid-flight, either by hovering over a sound made by a prey unseen or cruising slowly over meadows to detect the rustling of prey. These fine-tuned adaptations have worked for millions of years… and then came roads and the motor vehicle. Roads dissect habitat and owls must often cross them. Owls may be attracted to roadsides as the ditches and grassy verges provide good hunting opportunities in certain contexts. Automobiles travel faster and are more ubiquitous than anything the owls have had to contend with over their millions of years of evolution. The results can be quite devastating. Our species desperately needs to learn to slow down for life!

If you are interested in this topic, there are studies trying to determine roadkill hotspots (in order to devise prevention strategies) such as:

https://link.springer.com/article/10.1007/s11252-015-0465-5

https://onlinelibrary.wiley.com/doi/abs/10.1111/ibi.12593

http://www.cesam.ua.pt/files/Gomes_etal_2008%20owls_2008.pdf

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0079967

http://dspace.uevora.pt/rdpc/bitstream/10174/21237/1/Thesis_FINAL_CORRECTED.pdf

If you would like to participate, there are several iNaturalist projects documenting roadkill, in order to assist with such analyses, such as:

https://inaturalist.ca/projects/roadkill 

https://inaturalist.ca/projects/roadkills-of-texas

https://inaturalist.ca/projects/wildlife-diseases-morbidity-and-mortality

https://inaturalist.ca/projects/italian-road-mortality

https://inaturalist.ca/projects/roadkill-s-afr

https://inaturalist.ca/projects/wildlife-on-roads-in-ontario

Long-eared Owl (Asio otus), roadkill, July 2018, Manitoba Interlake, Canada.

On the vision of Barn Owls

“Humans are not so different from birds as you may think”:
Yoram Gutfreund, neuroscientist at Technion Israel Institute of Technology.

A new study   https://www.nytimes.com/2018/07/03/science/owls-vision-brain.html   shows that Barn Owl use “higher level processing” in visual perception (as do humans and chimpanzees, although in a different part of the brain). I thought this worth sharing after other discussions on the similarity of owl vision to human vision.

Yoram Gutfreund is speaking about visual perception in the above quote; however, it sums up other recent findings about animals and how they perceive the world more broadly, including the concept of animal cognition. I find humans to be extremely resistant to any notions of comparability with animals, even despite, for example, the growing body of evidence regarding the intellectual abilities of “bird brains” and increasingly convincing evidence of “theory of mind” in animals (once perceived as a uniquely human trait and still vehemently denied by some who cling to the notion of human superiority). I think this is why this type of study and this finding, which seems somewhat "obvious" perhaps, is new and previously little investigated.

To illustrate this post, I am sharing my photo of three immature Barn Owls (Tyto alba tuidara) exploring their world in a rural yard in southeastern Brazil. This photo was taken shortly after dusk using the existing lights of the farmyard and a single flash bounced off the building and underexposed (i.e. weak and indirect lighting). We found the owls by chance by their calls and we left the area quickly to allow the parents to feed them uninhibited but I was delighted to meet the welcoming homeowner and to learn that he appreciated having the owls around (as Barn Owls are not welcome everywhere - see other posts with the label "owls" for more on that topic).