New study reveals Varied Thrush as a species that is disproportionately vulnerable to window strikes on the west coast of Canada

A new study about bird window collisions out of UBC by Environment Canada biologists Krista DeGroot et al. reveals that Varied Thrushes are the species most often affected by window strikes in the west coast of Canada. This study showed for the first time, that during winter, Varied Thrushes are 77 times more likely to be involved in fatal window strikes.

Collision mortality is extremely high at UBC. More than 10,000 collision deaths occur per year at UBC. It was 4 times higher in the fall than a study done by Hager et al. in 2017 at college campuses across North America. This shows that window collision rates will also be high at homes and at other campuses and buildings in the Vancouver area and along the Pacific Coast.


In contrast to studies conducted elsewhere in North America, collision mortality in winter was as high as mortality during the spring migratory period at UBC.


This has detrimental implications for the large resident and overwintering populations of terrestrial birds in southwestern BC, including the Varied Thrush.

To read this interesting study that was just published by Oxford “Year-round monitoring at a Pacific coastal campus reveals similar winter and spring collision mortality and high vulnerability of the Varied Thrush,” please click HERE

Varied Thrushes are the species most likely to be involved in window strikes - Photo: Melissa Hafting


Comments

Post a Comment

Popular Posts

Dowitcher Identification

Image
Birders notoriously find it difficult to tell Short-billed and Long-billed Dowitchers apart. I have got a request to do an identification explanation on them so here goes, I hope it will be helpful. Short-billed Dowitchers and Long-billed look so similar. Using their habitat is helpful but not diagnostic. Short-billed Dowitchers tend to prefer Salt water and brackish water and Long-billed Dowitchers tend to prefer fresh water. However, I have OFTEN seen Short-billeds in freshwater and Long-billeds in brackish and salt water. Therefore, DO NOT rely on habitat. Another feature many people will tell you to rely on is spotting on the side of the flanks of Short-billeds and barring on the side of Long-billeds. Usually this is a mark that you can use but it is not always as distinct as you like. I have seen Short-billeds with a barred appearance to the flanks. It is only at the side of the breast where you have to look for this diagnostic feature for the spots on a Short-billed and t...
Read more

Hawk Identification Tips from every angle (Sharpie vs Cooper and Red-tailed Subspecies)

Image
I get several questions about the difference between accipiters. The most common ones are between Sharp-shinned Hawks and Cooper's Hawks and between Cooper's Hawks vs Northern Goshawks (to a lesser degree). Next, I get many questions dealing with a certain race of buteos the Western Red-tailed Hawk and Harlan's. So I thought I would do a post on these to help answer those questions. I will deal with Cooper's and Sharpies and not Goshawks because they are much more common here and look much more alike. My friend John Reynolds inspired me to write this up. COOPER'S AND SHARP-SHINNED HAWKS EYE COLOUR - YELLOW OR ORANGE? RED? Normally a juvenile Cooper's hawk has a bright yellow eye and a Juvie Sharpie has a orange eye but some cooper's can have a dull yellow eye that looks a bit orangish. Cooper's Hawks usually only transition to the orange eye colour when they are sub adults, so in good light, it's a very very reliable feature. However you ...
Read more

STINT IDENTIFICATION

Image
As per request, here are some tips that I hope will be helpful in identifying and differentiating Red-necked Stint from Little Stint. I will also do a brief intro on Long-toed and Temminck's Stint... if you build it they will come right?😉 Red-necked and Little Stints look very much alike in worn breeding plumage. The amount of Red on the face, throat and breast in Red-necked Stint is vary variable). They look even more alike in non-breeding plumage, that is why it is essential to learn structural differences to separate the two. They are similar to Semipalmated Sandpipers as well as Sanderlings. Both species are often confused for Red-necked Stints. Little Stints rarely get confused with Sanderling because they have a hind toe which helps differentiate it from this species. Sanderlings in breeding or worn breeding are usually confused with Red-necked Stints but they are much larger than Red-necked Stints. Let's first start with Bills in this complicated ID proces...
Read more

*Updated - The most famous Red-tailed Hawk is eating fish on the ground just like a Bald Eagle!

Image
Update - There are plans in the works to make a documentary film on this young Red-tailed Hawk who thinks he's an Eagle. You can read the latest news about that on CBC HERE . Watch this incredible footage of the little Red-tailed Hawk who grew up in a family of three Eaglets and 2 Bald Eagle Parents. He is imprinted now on Bald Eagles. He looks and acts just like one, as you can see here in the video below. He is standing over a large salmon carcass, just like a Bald Eagle would and he's eating the decaying flesh. Red-tailed Hawks like to eat voles and rabbits etc. not fish! Imprinting is usually irreversible according to raptor expert David Bird. However, I hope it's reversible so that he doesn't attempt to mate with a Bald Eagle, as the Eagle would kill him because it would view him as a Hawk. Eagle expert David Hancock said that the bird will likely starve and get killed by an eagle. He said this possibly can be prevented if someone grabs it and takes it to O...
Read more

1 year since I lost my father

Image
My dad and I whom I miss terribly. One year on since I lost him. Today would have been my mother's bday. Her name was Valerie and it is also the first year anniversary of the death of my beloved father, Arne. There is not a day that goes by where I don't think of them. Now for ever more the day of his death will be connected to her birthday, a very sad day but in a way that connection is beautiful to tie them together. My beautiful family before we lost both parents. I put flowers down at their grave to celebrate them both today. I hate that it is one year since I told him I loved him and hugged him. I miss him so very much. I miss his voice, his love and guidance and support. The ground for me feels shakier without his guidance and safety. I hate I will never see him again or talk to him again. Can't believe how quick time passes. This is why it is so important we treasure every single day to the fullest and tell those we love them. I will never forget the day he passed aw...
Read more