{"id":30565,"date":"2015-04-08T06:04:09","date_gmt":"2015-04-08T12:04:09","guid":{"rendered":"http:\/\/www.featheredphotography.com\/blog\/?p=30565"},"modified":"2015-04-08T06:31:09","modified_gmt":"2015-04-08T12:31:09","slug":"the-physical-transformation-of-displaying-male-sage-grouse","status":"publish","type":"post","link":"https:\/\/featheredphotography.com\/blog\/2015\/04\/08\/the-physical-transformation-of-displaying-male-sage-grouse\/","title":{"rendered":"The Physical Transformation of Displaying Male Sage Grouse"},"content":{"rendered":"

The physical transformation of\u00a0displaying male Greater Sage-Grouse would make a metamorphosing butterfly proud.<\/p>\n

Note: Each of these images was taken approximately two weeks ago in Wayne County, Utah. All but the first image were taken on an active lek.<\/em><\/p>\n

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\"sage<\/p>\n

\u00a01\/3200, f\/6.3, ISO 500, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

This is what the adult male looks like during breeding season\u00a0when it isn’t displaying.\u00a0 Note the black on chin and throat (absent in the female), extremely long tail and\u00a0yellow fleshy comb above the eye (less conspicuous in female though this male’s comb can’t be seen well here).<\/p>\n

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\"sage<\/p>\n

1\/1250, f\/7.1, ISO 800, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

But when the male is on the lek performing his strut display he almost looks like a different species. The tail becomes fanned and erect, the breast distended, yellow eye-combs\u00a0erect and more obvious and\u00a0long filoplume feathers arising from the back of the neck are exposed. He then inflates part of his esophagus contained in a muscular bag at the bottom of his neck<\/p>\n

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\"sage<\/p>\n

\u00a01\/1250, f\/7.1, ISO 800, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

Here’s a front view at about the same stage of the display as the previous image. There are two yellowish patches of bare skin (cervical apteria) on the lower throat and breast that at this point are still hidden but…<\/p>\n

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\"sage<\/p>\n

\u00a01\/800, f\/9, ISO 800, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

they soon become inflated and highly conspicuous.\u00a0These air sacs bulge repeatedly as he heaves the esophageal expansion up and down during the display (all the time keeping his outreached wings stiffly at his sides). Sound production coincides with this expansion and deflation of the air sacs. The expanded air sacs provide a\u00a0matronly look (IMO)…<\/p>\n

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\"sage<\/p>\n

\u00a01\/800, f\/9, ISO 800, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

and if you click your shutter at just the right moment that\u00a0look is exaggerated.<\/p>\n

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\"sage<\/p>\n

\u00a01\/800, f\/6.3, ISO 1600, Canon 7D, Canon<\/em> EF500mm f\/4L IS II USM +1.4 tc, not baited, set up or called in<\/strong><\/p>\n

A side view shows that the air sacs briefly resemble two inflated balloons giving the poor guy a distinctly bosomy appearance.<\/p>\n

The sounds\u00a0made during the display are both vocal and nonvocal. The nonvocal portion (a “plopping” sound called an air sac pop)\u00a0is produced and amplified by the inflated air sacs. The entire sound array can be heard here<\/a>.<\/p>\n

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Research shows that though there are typically many grouse of both sexes on the lek most of the females mate with the same one or two males. From BNA Online:<\/p>\n