My last weekend at the beach was mainly spent on the beach, however, on Saturday morning I got in a few hours birding, visiting the estuary mouth where I saw my first
Yellow-crowned Night-heron roosting in a tree, three
Collared Plovers, and a flock of c.15
Tricoloured Munias flew over.
Waders consisted of c.30
Semipalmated Plovers, four
Wilsons Plovers, 14
Least Sandpipers, four
Willets, one
Whimbrel, two
Ruddy Turnstone, and six
Sanderling. On Sunday morning, it appeared like there was a small feeding frenzy offshore, with fish leaping two metres clear out of the sea, being chased by whatever predators lurked below. On a couple of occasions,
Magnificent Frigatebirds swooped down to catch the fish in mid-air. Also in attendance were four
Brown Boobys and eight
Royal Terns.
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| Yellow-crowned Night-heron |
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| Royal Tern |
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| Neotropic Cormorant |
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| Wilson's Plover |
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| Collared Plover, Least Sandpipers, Semipalmated Plovers and Royal Terns |
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| Chestnut-mandibled Toucan |
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| Looking south just after sunrise. |
Great captures and cool blog! I initially noticed your "neotropic cormorant vs fish" shot. Wow that looks like a pretty big/wide fish (do you know what kind?) caught and staring down the bird's throat here!
ReplyDeleteSo in the end the Cormorant really managed to gulp that entire thing down okay? Does the fish put up a good fight, if eaten, does the unlucky prey get swallowed wriggling as well?!
Hi! Thank you! The fish is some sort of flatfish. As to the species, I have no idea. It took the cormorant about 2 minutes to swallow it. The fish wasn't actually wriggling that much, but was still alive. Birds like cormorants are used to eating fish like this on a daily basis and are specially adapted with very wide gapes and elastic skin in their neck that can accommodate a large fish being swallowed. They also always swallow fish head first so that the scales don't cause any friction. I have however seen mergansers try to swallow a flatfish for 10 minutes before realising it was too big and give up!
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DeleteOh insteresting! That must be some hungry bird!
Still, it seems difficult to me that the Cormorant can deal with this large fish! So the bird was actually able to fit that whole thing down its long/skinny throat completely somehow?? I have never witnessed an event like this before.
I feel somewhat perplexed over how it actually happens, wouldn't the fish stand a chance of escaping or even damaging (it’s sharp fins, wriggling, biting, etc.) the bird's throat/stomach if eaten in that condition?!
It’s hard for me to imagine that the resistant fish (wouldn't the prey also go into a desperate "survival mode" once it realized that it hit the stomach?) doesn't turn around inside the elastic gullet and how the bird can keep down/digest such an object with no issues?
I don't have much knowledge about these events and am mostly curious, I appreciate any feedback/explanation.
Sorry for all of the questions, have a good week ;)
With a flatfish, the flat "fins" either side of the body are quite flexible so would easier to swallow than you would think. It also wouldn't surprise me if the birds sometimes bite the fishes head to subdue any wriggling. Obviously, the longer the fish stays out of water, the weaker its muscles will become. I imagine cormorants have valves in their stomachs which would allow the fish in, but stop it from escaping back out.
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