“I managed to observe a Purple Heron (Ardea purpurea) in action after about an hour of waiting. Correct me if I’m wrong – the prey seems to be an eel. [Note: Marcus Ng a.k.a. budak – see comment below – has identified the eel as Oriental Swamp Eel or Monopterus albus.]
“This Purple Heron was observed standing in shallow water next to reeds on the bank of a pond in Lorong Halus. It was very patient and stayed in the same position with minimal movement for close to 50 minutes. It stretched and extended its long neck when it caught sight of preys.
“There were two episodes of false alarm where either the prey got away before it can strike or it lost sight of the prey.
“When it finally strike into the water, it was at lightning speed. It had caught an eel that put up a fierce struggle by coiling itself round the predator’s bill.
“Flustered, the heron dropped its prey into the water. However, the prey had no chance to get away.
“Plunging its head into the water, the prey appeared to be speared. There was blood oozing out from a wound on the underside of the prey.
“The heron manipulated with its prey, holding it near its head and swinging it by quick twisting movement.
“When the prey did not put up further resistance, it was washed a few times. The prey was then gulped down the heron’s throat head-first.
“After the heavy meal, the heron was observed drinking and gaping a few times. Not sure whether this and its odd posture with neck expanded help it to digest.”
Kwong Wai Chong
Singapore
5th April 2015
budak
eel looks like Monopterus albus swamp eel http://www.ecologyasia.com/verts/fishes/asian-swamp-eel.htm
YC
Thanks Marcus for the ID.
Lee Chiu San
Two points.
First, Monopterus albus bites viciously, as anyone who has ever fished for them will know. If the heron had felt that it had not managed to get a grip close enough to the head to prevent being bitten, the prudent thing to do at that stage would have been to drop the eel and try to grip it in a safer position, which is what the heron did.
Second, the distension of the neck could have been caused by the eel. It could still have been alive after being swallowed, and could be thrashing around in the heron’s gullet, causing the odd posture.
Anyone who does not believe that prey can still live inside a bird should try feeding whole, wriggling mealworms to baby birds. They will chew their way out of the bird, killing it in the process. Most (not all) adult birds have the sense to bash mealworms to death before attempting to swallow them.
Why was the heron not afraid of the eel trying to chew its way out? Fortunately for the bird, eels have needle-like teeth for grasping prey, not chisel-like teeth for chewing their way out.
YC
Thanks for the above. We are still learning…
Kyle
Amazing series! That looks like a big eel staring down its captors throat here! So in the end the bird won the struggle and was really able to gulp down the whole thing okay?? Does the prey put up a good fight, if eaten, does the unlucky/desperate fish get swallowed wriggling all the way as well?! It wonder if it would stand a slim chance of escaping its stomach if eaten in that condition?