Santa Marta Screech-Owl described to science

The Santa Marta Screech-Owl has finally been described as Megascops gilesi by Niels Krabbe. First "discovered" in 2007, I took the photo below in 2008. It took 10 years from discovery to description! See: https://www.hbw.com/new-species/santa-marta-screech-owl for a short write-up or read the full paper at: http://asociacioncolombianadeornitologia.org/wp-content/uploads/2017/12/16eA08.pdf.

Citation 
Krabbe, N. 201. A new species of Megascops (Strigidae) from the Sierra Nevada de Santa Marta, Colombia, with notes on voices of New World screech-owls. Ornitología Colombiana 16: eA08-1.

Snowy Owl, globally Vulnerable

The Snowy Owl has recently been listed as globally VULNERABLE. See: http://datazone.birdlife.org/species/factsheet/snowy-owl-bubo-scandiacus or http://www.iucnredlist.org/details/22689055/0. Population size and the extent of the declines are both poorly understood; however, despite the uncertainty, there is sufficient evidence for a listing of Vulnerable. We don’t really know why the numbers are declining but reduced food supply (perhaps due to climate change) and the high rate of collisions with vehicles and infrastructure have been suggested.

Shorebird conundrum

So, in terms of conservation, which of these shorebirds in the top row and bottom left and bottom centre is not quite like the others (the photo in the bottom right hand is a clue)? This quizz pertains to a newly published study that showed high survivability in 6 species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014: American Golden Plover, Dunlin, Semipalmated Sandpiper, Western Sandpiper, Red-necked Phalarope, and Red Phalarope with one important difference. The conclusion of the paper is that the main conservation concern may be at stopover sites or wintering sites, see: rhttp://www.bioone.org/doi/10.1642/AUK-17-107.1 ... scroll down to see the answer:
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This study looked at breeding and survivorship of six species: Western Sandpiper (top left), Dunlin (top centre), American Golden-Plover (top right), Semipalmated Sandpiper (bottom left), Red-necked Phalarope (bottom centre) and also Red Phalarope (not pictured). They showed good breeding success and high survivorship in all except the arcticola subspecies of Dunlin. So how does the arcticola Dunlin differ from the others? Well, it breeds in North America but it winters in Asia and uses the East Asian Flyway (all of the others stay within the Americas). Stop-over sites in the East Asian Flyway have deteriorated so drastically and there is so much habitat loss that it affects survivorship. This is a major problem not just for these Dunlin but also for many Asian shorebirds such as the Spoon-billed Sandpiper (the clue is the bottom right photo of a Dunlin beside a Spoon-billed Sandpiper, a photo that I took in South Korea). It goes to show that even if all is well on the breeding grounds, a species can encounter great danger elsewhere in its range (on migration or on the wintering grounds). It is important to remember this connectivity and its consequences when we talk about Canadian Species At Risk.

Great Horned Owl (Bubo virginianus) colour in Manitoba, Canada

I live in Manitoba, Canada within the range of the subarcticus subspecies of Great Horned Owl. Of the many hundreds I have seen here, where they are common and easy to see, especially in the Prairie Pothole region, the vast majority have a pale colouration. The bird on the right of the photo collage below would be a fairly typical example in my neck of the woods though some are paler than this, some darker, and some have slightly warmer tones, i.e. more warm buff or even a rufous wash to the pale areas of their plumage. Every so often I find a Great Horned that is so warmly coloured (like the one in the photo on the left of this collage) that it makes me wonder if it could be an individual of the nominate subspecies that has dispersed north. I am especially curious when I find such birds in fall at a time of year when dispersal is most likely to occur, especially natal dispersal. Natal dispersal is when young owls gain independence from their parents and vacate the territories and home ranges of their parents in search for a place to call their own. Of course they have a lot in store for them ahead, including surviving the toughest time of their lives, their first winter, before they can claim a territory and find a partner. Natal dispersal (the distance from an owl’s birth place to the site of its first reproductive effort) is sometimes short but can sometimes be hundreds of kilometres. Dispersal during food shortages can sometimes also be distant. Fall/winter is therefore the time when one might chance upon an admixture of subspecies as a product of dispersal. It might even be possible that such far dispersing birds find a mate of a different subspecies (subspecies can by definition interbreed) and to produce “intergrade” offspring but it is extremely difficult to prove that for a species with such a clinal range of colouration as the Great Horned Owl (from the super dark birds of the west coast to some pale northern birds that could almost be mistaken for a Snowy Owl to some of the intensely rufous birds of the wet and warm parts of the range). We have seen some fascinating pairing of light and dark birds in Alberta, for example. The rufous individual Great Horned shown in the left photo of this collage was photographed recently just 175 metres away from the site where the other photo was taken and the markings reveals that this bird is not one of the local nesting pair. My best guess is that this bird is a dispersing individual whose presence will not be tolerated for very long by the resident guardians of our cottontail-rich neighbourhood. With this colouration, it is tempting to speculate that this bird comes from within the range of B. v. virginianus but we will likely never know.      

For a little context, the rufous bird on the left is being mobbed by crows and on alert for that reason. The pale bird on the right was perched near the river but within sight of a well-used public trail and was keeping an eye on the passers-by, including one with a small dog (dogs are often perceived as a threat to the young instead of a potential snack if you are wondering). Both photos are taken at a distance of greater than 50 metres and heavily cropped.