[Tweeters] killer grebe, curious otter
dennispaulson at comcast.net
Mon Apr 25 15:54:58 PDT 2016
I just returned from Magnuson Park, where I saw some astonishing things. Walking near the shore of the shore lagoon (closest pond to the lake), where I conduct a weekly dragonfly survey, I first scared out of the reeds 2 small Mallard ducklings, then soon thereafter a Pied-billed Grebe. I was surprised to see both—the ducklings without a mother and the grebe in dense vegetation right at the shore. I watched the ducklings paddle their way toward the W end of the pond out from the shore vegetation, and they then moved farther out into the open water. As I watched them, a big splash occurred and one of the ducklings disappeared. I thought “who put a largemouth bass in this pond?” But then a Pied-billed Grebe surfaced at the spot. I was trying to get a photo so didn’t see exactly what happened after that except I could see one duckling hurrying back into the vegetation.
A few minutes later, a female Mallard came in calling constantly and swam past me along the shore. She was obviously looking for her downy young, and I finally saw one of them swimming with her. But one, not two. They made their way farther along the shore, the female calling all the time, and then there was another commotion in the cattails, and the female and young rushed out of them. And there was the grebe again, had come up just behind them. The two of them made their way quickly back down the shore and passed right in front of me. The grebe stayed at its side of the pond. I presume it was a male, as it called frequently.
Meanwhile, a grebe, I think the same one, flew past in front of me, splashing along the water without really leaving it. I was frustrated that I didn’t have a single-lens reflex with long lens to follow it, as flight photos of Pied-billed Grebes are probably almost as rare as grebe’s teeth. But then another one flew from a different spot, and I tried in vain to follow it with the Canon SX50, a camera not meant for that job. I wondered what was going on, when the first grebe flew toward me again (!) from where it had landed earlier. Then I saw the reason—a River Otter surfaced right where that grebe had been. The otter played around in the western end of the pond, swimming toward me to check me out each time it surfaced, and this I did manage to photograph. I concluded it was the otter, swimming underwater, that had freaked out the two grebes.
The otter finally disappeared, and I suspect it went through the big culvert under the road to the next pond. Shortly after that, I found the second duckling floating dead with some down missing from its head. At least one of the grebes is a duckling killer, and I wonder if that’s why there were only two ducklings when I first saw them, as the average clutch size of a Mallard is upwards toward 10. I suspect the grebe(s) may have killed them one by one. Of course, an alternative conclusion would be that a River Otter in the pond could cause the same loss, but my money is on the grebe(s).
I saw nothing like this last summer, when both bird species and their young shared the pond seemingly in piece. This was the first otter I’ve seen there in six years of dragonfly surveys. Oh yes, I found a California Darner and quite a few Pacific Forktails.
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