Tag Archives: jackdaw

Of Jackdaws

[youtube http://www.youtube.com/watch?v=fYwRMEomJMM]

A juvenile western jackdaw (Corvus monedula spermologus) is served water by some nice humans in Supetar, Croatia.

While jackdaws are still listed as in the genus Corvus (with other crows) in most literature, many workers argue that the two species of jackdaw (western, C. monedula, and daurian, C. dauuricus) should be in their own genus Coloeus.  Indeed, they have long been listed in the ‘sub-genus’ Coloeus and a 2007 paper looking at the genetic diversity, using mitochondrial DNA of certain species of corvids, supports the assertion that jackdaws should be in their own genus.  In fact, the International Ornithological Union and Birds of South Asia: The Ripley Guide by Rasmussen and Anderton both list them as genus Coloeus.

Semantics aside, these small corvids have long been recognized as being morphologically distinct from the rest of the genus Corvus.  They are small (the smallest of genus Corvus) and very sociable; as evidenced by this video.  They are a common urban bird and thrive just as well in human dominated landscapes as they do in remote landscapes, like a number of other corvids.  However, jackdaws also differ from other crows in that they nest in crevices/holes, much to the distress of many a chimney-owner.

And while I’m on the topic of crows that are proposed as distinct from the others, another sub-genus, Corvultur, has been previously proposed for the fan-tailed raven (C. rhipidurus), white-necked raven (C. albicollis), and thick-billed raven (C. crassirostris) due to their close geographical relationship and unusually thick bills.  However, this division is not very robust, and a 2012 study placed white-necked and thick-billed ravens as closely related, but fan-taileds sorted out closer to pied crows (C. albus) and then common ravens (C. corax) and brown-necked ravens (C. ruficollis).  However, unlike the Corvultur, both jackdaw species still remained very distinct from the rest of genus Corvus, forming the most basal group.

All of that said…I hope you enjoy this video of a jackdaw getting a nice cool drink of water after coercing some primates into opening a bottle and pouring a cap-full for it.

(Preview image for this post by John Haslam from Dornoch, Scotland.)

Corvid Noses

Mostly because I can, and also because it is a pet peeve of mine.NO NOSTRILS!!!

Quote from: Madge, S. and Burn, H. 1999. Crows & Jays. Princeton University Press, New Jersey. [link]

Photo credits:

Black Currawong: JJ Harrison via Wikimedia Commons
Australian magpie: Aviceda via Wikimedia Commons

Blue Jay: DickDaniels via Wikimedia Commons
Green Jay: Alan Wilson via Wikimedia Commons
Eurasian Jay: Mark Medcalf via Wikimedia Commons
Clark’s Nutcracker: Jason Popesku via Wikimedia Commons
Black-Billed Magpie: David Merrett via Wikimedia Commons
Green Magpie: Thomas Ruedas via Wikimedia Commons
Rufous Treepie: Jon Connell via Wikimedia Commons
Pander’s Ground-Jay: Alastair Rae via Wikimedia Commons
Alpine Chough: Ken Billington via Wikimedia Commons

Common Raven: David Hofmann via Wikimedia Commons
American Crow: cuatrok77 hernandez via Wikimedia Commons
Jackdaw: Tony Hisgett via Wikimedia Commons
House Crow: J.M.Garg via Wikimedia Commons
Jungle Crow: aomorikuma via Wikimedia Commons
White-Billed Crow: Josep del Hoyo via The Internet Bird Collection
New Caledonian Crow: original author unknown via Google Search
Pied Crow: Lip Kee Yap via Wikimedia Commons
White-Necked Raven: Greg Hume via Wikimedia Commons
Thick-Billed Raven: original author unknown, via Wikimedia Commons
White-Necked Crow: ZankaM via Wikimedia Commons
Australian Raven: Brett Donald via Wikimedia Commons

Rook: Andreas Trepte
Grey Crow: Brian J. Coates via The Internet Bird Collection
Grey Crow: mehdhalaouate via The Internet Bird Collection

Mobbing Predators

Oh no, a not-corvid!  However, I thought I’d share what has been keeping me so busy.  Meet Rusty, my red-tailed hawk (Buteo jamaicensis), beautifully photographed by my friend Melissa Penta

My husband and I obtained our apprentice falconry licenses and Rusty here is our first bird.  He’s a juvenile (hatched in the wild this April or May) and was trapped in January.  He’s a small male and his personality has made him an absolute delight to work with.  If you have any questions about falconry, feel free to ask, however, since this IS a corvid blog, I’m going to briefly talk about the relationship between these guys and corvids.

I’m sure if you have spent any time observing or reading about crows you know they exhibit mobbing behavior.  This means they dive-bomb, peck, chase, and scream at predators they find threatening, even going after predators many times their own size.  (I have certainly been mobbed during banding season!)  What makes it “mobbing” behavior is that they recruit family, friends, and neighbors to help them drive the predator away, or anything perceived as a threat, no matter how seemingly benignSmaller crows will even mob bigger crows.  It’s not just the crows that do this, many corvids show this behavior such as magpies and jays (but seriously, what won’t jays scream at?), however, this post will focus on crows.

This behavior often looks quite dickish, as many times the target of the crows’ ire is simply sitting still in a tree or trying to eat a meal.  However, raptors are quite a threat to crows.  Even if one may seem too small to be a threat you need to keep in mind that raptors are quite powerful for their size (here is a video of a sparrowhawk on a jackdaw; please note this is a predator/prey interaction video and it may be distressing to sensitive viewers…though spoiler alert, the jackdaw survives).  Even cousins aren’t sacred as ravens are often chased off as vigorously as a raptor because they can certainly be a threat (here is a juvenile raven eating a fledgling crow).

So, is it a mystery why crows might act so defensively to any predator/threat they see?  Not really.  I find anti-predator behaviors quite interesting.  When mobbing occurs (note: this is also seen in other animal taxa, not limited to corvids or even birds) you don’t just see kin helping kin, you sometimes see entire communities of unrelated individuals banding together to make their neighborhoods safer.  Sounds a lot like what we do!

So as I fly Rusty and hunt small game with him I fully expect to get some crow visitors who are none too pleased to have a hawk in their domain (in fact we’ve already had a few at a local park), but in the end, can we really blame them?