This blog introduces the breeding and child-rearing struggle of little grebes in Inokashira Park in 2017 with photos.
Threats approaching from below the surface
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The clear water in June is getting cloudy day by day.
Blue-green algae also occur in places where the flow is slow, and it seems that water purification has not caught up with the high temperature and sunny days.
On August 5, only three chicks can be found in the nest of the gourd bridge, the little grebe for the first time in three days.
There were no chicks on the feathers of the returning parent bird, and one chick seems to have been killed by a foreign enemy.
No one has seen it, so the detailed cause is unknown.
Perhaps it is difficult to catch fish and shrimp in the water, the frequency of feeding parent birds is decreasing.
I also feel that the proportion of insects that feed on them has increased.
It seems that the cause is that the water has become muddy.
Parent birds are often hungry or leave their nests to leave their chicks in search of food and often find it difficult to return.
It's an action that wasn't seen until a few days ago.
Taking such a chance, an incident happened to the chicks.
Three chicks followed the parent birds that fed the chicks and left the nest.
The chicks are probably hungry.
The parent bird didn't seem to notice the chicks that were chasing after him, so he went somewhere far away.
The parent bird may be hungry too.
As it was, all three remaining chicks floated on the surface of the water in an unprotected state.
There, a black shadow slowly creeping up from under the water.
The black shadow gradually approached the chicks from a distance of about 10 meters.
Also, the muddy water delayed the chicks from realizing that they were in danger.
(The picture above is the moment when the chicks notice the creeping shadow and run away all at once.)
As the chicks realized the danger and ran away, the black shadow caught one chick at a tremendous speed.
It wasn't the last chick that was late to escape, but the chick that escaped first, or conversely, the chick that approached the blackest shadow and quickly noticed and escaped.
It must have been locked on by the black shadow.
I try to escape with the last power,
The chick struggled to escape and raised her head to the surface several times.
However, the turtle dived deeply, and the hope soon came to me.
The remaining two chicks remain stunned and are in a state of daze until their parents return, drifting on the surface of the water.
I couldn't even return to the nearby nest.
I was worried that they would be attacked again, but after a while, the parent bird returned and returned to the nest, and the chicks escaped the difficulty.
The parent bird seemed to notice that the number of chicks had decreased by one, and dived into the surrounding area and underwater to search for chicks.
The true identity of the black shadow is the exotic red-eared slider.
Perhaps the first one to disappear must have been killed by this guy.
Anyway, he is relentlessly wandering around the grebe's nest with his head out.
It occupies the taste or is definitely wandering around the nest aiming at the chicks.
The parent bird also seems to know that the turtle is the culprit, and tries to get rid of the turtles that roam around the nest.
It would be difficult for the parent bird to be bitten by the turtle, so it's a little sloppy.
A parent bird and a waist that are wary of turtles approaching the nest
Red-eared slider that sticks out of the water and relentlessly roams around the nest
Two alien species were exterminated in the pond of Inokashira Park.
However, those who could not be exterminated quickly increased in number due to their strong fertility.
It is said that there is a plan for shaving this winter, and it will be held regularly once every few years after that.
At that time, I would like you to get rid of this outpatient turtle.
But while the water is being drained, the little grebe also has to blame somewhere.
Trouble continues.
The red-eared slider is imported in large quantities as a red-eared slider, and the number is roughly 100,000 a year.
It's cute when it's small, but as it grows up, it smells and is ferocious, and it's hard to keep it.
Red-eared sliders are more fertile than native turtles, and native turtles have lost competition and are reducing their numbers.
Little Grebe, who lost two chicks, don't repeat the same mistake.
The little grebe of Nanai Bridge, which was in danger of being attacked by a cormorant, was protected by a parent bird, and as of August 5 (2027), three chicks are growing safely.
All the photos this time were taken with Panasonic G DMC-GH4 in 4K video and captured as photos.
I hope to upload a video of this event someday.
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to be continued
It's been a while since I wrote the blog, but I made a video of what happened at that time, or rather the life history of this pair.
It is a masterpiece that exceeds 30 minutes.
If you are interested, please take a look.
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