Tag: impale

Loggerhead Shrike Attempting To Impale A Grasshopper

Shrikes are well-known for impaling their prey on sharp projections like thorns or barbed wire as a means of food storage – they’re called “butcher birds” for good reason.  I suspect the behavior to do so is innate but to become skilled at it takes practice. This past summer I found this Loggerhead Shrike on a fence on the Montana farm where I grew up.  It had already captured the grasshopper when I arrived on the scene. First, my standard disclaimer for behavioral sequences.  This bird was strongly sidelit so I seldom got a catch light and the light was harsh.  To compensate, I did more processing with these images than I normally do because my intent is to show the behavior as well as possible, even though image quality suffered from the processing.   Almost immediately I could see that the shrike was going to attempt to impale the grasshopper on the barb just below and in front of the beak of the bird.     Impaling prey apparently isn’t an easy task.     From all the contortions the bird went through…     I’d assume that part of the problem was the awkward angle the shrike was at…     to get proper leverage to complete the task.     At one point the bird nearly fell off the fence.     After a few moments the shrike gave up, turned its back on me with the grasshopper between its legs (and a gob of grasshopper on its bill) and seemed to contemplate what…

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A Few Recent Loggerhead Shrikes

There’s always a few Loggerhead Shrikes that winter-over on Antelope Island and I find them to be fascinating subjects.   Their approachability is very unpredictable but occasionally they’ll allow me to get close, especially when it’s very cold in the mornings or if they’re about to hack up a pellet.  These are images I was able to get in the last few weeks. ***Note: The last image in this post is graphic.  If your sensibilities might be offended by such a photo please stop scrolling before you get to the last (6th) image.    1/3200, f/5.6, ISO 500, 500 f/4, 1.4 tc This bird was practicing its springtime melodic repertoire a few weeks early (image taken on 2/5/12).  It was a relatively warm, sunny morning and it was singing its little heart out (if you can call shrike calls “singing”).        1/2000, f/6.3, ISO 400, 500 f/4, 1.4 tc With their black masks these shrikes always remind me of little bandits and they have an attitude to go along with that perception.  They get their name from their unusually large head (loggerhead means “block head”).        1/8000, f/5.6, ISO 500, 500 f/4, 1.4 tc I like the soft, even light and the setting in this image even though the twigs in front of the bird may not be ideal for some.        1/640, f/7.1, ISO 640, 500 f/4, 1.4 tc  I’m including this shot just for fun.  I liked the fluffy, relaxed pose to go along with the yawn.        1/1250, f/7.1, ISO 500, 500…

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Birds, Spiders, Brine Flies and Mercury Contamination on Antelope Island

Last Sunday I found this Northern Shrike on Antelope Island enthusiastically singing away as if spring were already in full bloom.  Their predatory habits and interesting behaviors make them a favorite species for me but when I got home that day I read an article in the Salt Lake Tribune that made me wonder just how healthy their populations near the Great Salt Lake really are.    North end of Antelope Island, 2/5/12 The reason for my concern is a bit complex but I’ll summarize:  For over 100 years smelting operations have been responsible for high levels of elemental mercury in the Great Salt Lake and its sediments.  Microorganisms in the lake convert the mercury to methyl mercury which is the toxic form of the element that can be absorbed by tissues of living things.  Brine fly larvae living in the lake then absorb the methyl mercury and when they hatch the adult flies are consumed by spiders living in the vegetation around the lake.  Finally, those spiders are eaten by the many bird species living and nesting along the shoreline.  But very little is known about the movement of mercury compounds through Great Salt Lake ecosystems, including the possible effects of toxic methyl mercury on birds so Westminster College’s Great Salt Lake Institute was recently awarded a $250,000 grant from the W.M. Keck Foundation to study its possible effects.      Antelope Island causeway, 8/29/11 The number and total biomass of brine flies in late summer around the lake literally boggles the mind but this shot should give you some idea.  It was taken in late August of…

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