{"id":106492,"date":"2022-01-23T06:18:33","date_gmt":"2022-01-23T13:18:33","guid":{"rendered":"https:\/\/www.featheredphotography.com\/blog\/?p=106492"},"modified":"2022-01-23T08:59:55","modified_gmt":"2022-01-23T15:59:55","slug":"male-common-goldeneye-a-hunting-hat-trick","status":"publish","type":"post","link":"https:\/\/featheredphotography.com\/blog\/2022\/01\/23\/male-common-goldeneye-a-hunting-hat-trick\/","title":{"rendered":"Male Common Goldeneye – A Hunting Hat Trick"},"content":{"rendered":"

In this series we’ll see why birds that eat crayfish usually shake them violently before swallowing them. It’s a behavior that pays off.<\/p>\n

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Yesterday morning this young male Common Goldeneye proved to be an excellent hunter, even at his relatively young age. In just a few minutes I watched and photographed him as he caught and ate three crayfish. This is crayfish #1.<\/p>\n

Most birds I see with crayfish prey shake the stuffing out of them before eating them, which is what this guy was doing. The purpose of shaking them is partly to stun or kill the crayfish but it often has another purpose that will become evident later in this post.<\/p>\n

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Soon after this photo was taken he turned his back to me and swallowed the crayfish.<\/p>\n

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Four minutes later he’d captured crayfish #2. I was lucky because each time he caught one he swam closer to me in order to avoid other birds near the shore that might steal his prize.<\/p>\n

One thing surprised me. There were lots of gulls nearby and usually gulls will attempt to steal prey, including crayfish, from other birds. But on this morning I never saw any such attempts. The gulls just sat on the water and ignored him and I don’t know why.<\/em><\/p>\n

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As soon as he got far enough away from the shore and other birds he…<\/p>\n

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began his shaking routine with crayfish #2.<\/p>\n

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This time he kept it up for quite a while.<\/p>\n

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Soon the crayfish wasn’t moving much and eventually I thought…<\/p>\n

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it might be dead. But he continued to shake it and…<\/p>\n

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for good reason. 36 shots later at least one of the primary weapons of crayfish, two large pinching chelipeds or pincers, appeared to be primed for action. Even the much smaller pincers on the walking legs were open and apparently in defensive mode.<\/p>\n

For those who may be interested, this crayfish is almost certainly a male. Crayfish “tails” (their abdomen really) have a pair of backward-pointing swimmerets on the ventral side of each segment and on males the anterior pair are enlarged and hardened. Even though the abdomen of this crayfish is kinda torn up it does appear to be a male.\u00a0<\/em><\/p>\n

After some more shaking the goldeneye turned his back to me (again) and swallowed the crayfish.<\/p>\n

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So, let’s move on to crayfish #3 which he caught about four minutes after swallowing crayfish #2. Not long after he captured this one I was lucky enough to document another reason why…<\/p>\n

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birds shake crayfish so violently, especially those crayfish with large pincers.<\/p>\n

Besides being potentially dangerous the chelipeds are large and stick out from the body, making it difficult to swallow the crayfish whole with them still attached. So one of the purposes of shaking is to amputate the chelipeds. Here we see one of them flying off at upper right.<\/p>\n

In the next shot in the burst that pincer was…<\/p>\n

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still flying through the air, which is an indication of just how violent the shaking was.<\/p>\n

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With both big pincers gone he…<\/p>\n

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gobbled it down. This time he forgot to completely turn his back to me.<\/p>\n

I’ve photographed Pied-billed Grebes using a similar shaking technique<\/a><\/span><\/span> to remove the chelipeds many times but I believe this was the first time I captured it in Common Goldeneyes.<\/p>\n

What’s good for the goose is good for the gander. Or something like that…<\/p>\n

Ron<\/p>\n

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Note: Here’s what Cornell has to say about this technique in Pied-billed Grebes. I suspect much of it applies to other crayfish-eating birds, including Common Goldeneyes.<\/em><\/p>\n

“Pinches and handles crayfish as it does fish. Removes larger claws by holding appendage in bill just behind claw, and vigorously shaking until claw breaks off. Swallows crayfish tailfirst; remaining appendages fold alongside prey body, facilitating swallowing”.<\/em><\/p>\n

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In this series we’ll see why birds that eat crayfish usually shake them violently before swallowing them. It’s a behavior that pays off. (14 photos)<\/p>\n

Continue reading<\/span><\/i><\/a> <\/p>\n","protected":false},"author":2,"featured_media":106501,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[334,376,392],"tags":[2847,3728,1168,91,2019,6143,6142,211,6140,6139,6141,311,3727],"class_list":["post-106492","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-birds","category-common-goldeneyes","category-feeding-bird-behaviors","tag-bucephala-clangula","tag-chelipeds","tag-claws","tag-common-goldeneye","tag-crayfish","tag-hat-trick","tag-how-to-tell-sex-of-crayfish","tag-male","tag-pincers","tag-shaking-prey","tag-swimmerets","tag-utah-2","tag-walking-legs"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/featheredphotography.com\/blog\/wp-content\/uploads\/2022\/01\/common-goldeneye-9663-ron-dudley.jpg","jetpack_shortlink":"https:\/\/wp.me\/p1zzJh-rHC","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/posts\/106492","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/comments?post=106492"}],"version-history":[{"count":5,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/posts\/106492\/revisions"}],"predecessor-version":[{"id":106543,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/posts\/106492\/revisions\/106543"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/media\/106501"}],"wp:attachment":[{"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/media?parent=106492"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/categories?post=106492"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/featheredphotography.com\/blog\/wp-json\/wp\/v2\/tags?post=106492"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}