Greetings all,

I had a little time left over this afternoon so I decided to run around Green Lake instead of my usual neighborhood run.
Light rain, 40-some degrees F., few people there at that time (about 2:45 PM).
Earlier this week I spoke with Gayle Garman and Richard Fleming, who walk the lake regularly and they had mentioned a few of the things I saw this afternoon. Well over two dozen Pied-billed Grebes. About 40 Common Mergansers. The highest number of Hooded Mergansers I've ever seen at the lake. Two groups of 12-15 and one group around 20.

The last group was actively hunting in the shallows in the bay in the northwest corner. As I ran up I thought I saw two Pied-billed Grebes mixed in with the hoodies, so I slowed down and followed the group (at a slight distance) for a good five minutes as they worked their way along shore. There were at least 3 Pied-billed Grebes moving along and diving among the group of hoodies. I've never seen pied-billes join any other diving bird during foraging and actually, back in 1999 the literature only mentioned pied-bills associating with Tricolored Heron and Snowy Egret, feeding near them, although they may feed cooperatively with the Snowy Egrets. There also is one report of Boat-tailed Grackles working the shoreline while pied-bills worked the shallows, mutually benefiting when grasshopper nymphs trying to escape one predator would fall prey to the other. I've been trying to keep up with pied-bill litetrature, but have not come across any feeding association reports since 1999. So to my knowledge this is the first reported instance of pied-bills and hoodies, if not cooperating, then at least hunting in synchrony. The grebes would dive at the same time as the majority of mergansers. During my brief observation I only saw three hoodies come up with prey items (cannot vouch for how many prey items either species swallowed under water). All three mergansers came up with slender fish, about the length of their bills, but because I had no vision-enhancing-devices along, I don't know any more about what prey they may have been after (other than 'fish').

All of this only goes to show how easy it is to see something that (when reported) adds to our knowledge of bird behavior.

Apparently there's a log floating way out in the lake. Again, my vision isn't that good, but I deduced this from the fact that there was a line of 20+ cormorants standing in the middle of the lake (there are no structures out there to my knowledge). Presumably they're all Double-crested Cormorants, since I've only seen a single Pelagic Cormorant on the lake once during the 20 years when I lived near the lake and spent many hours bird watching there.

Besides some 60 Gadwalls, about 100 American Wigeons (I'm told there is at least one male Eurasian among them but I didn't see him today), American Coots, Mallards, a few Northern Shovelers, a Bald Eagle on the island, a Cooper's Hawk trying to evade the numerous crows on their way to their communal roost at Forster Island (Arboretum) fleeing low into Lower Woodland Park (accipiter larger than a crow, with long rounded tyail and head protruding well in front of the wings' leading edge; I'm again playing the odd here with my id.), the only other bird of note (to me) was an adult Green Heron perched less than a foot over water in a small tree along the southwest shore (within 10 feet of the path). This was between where Kirkwood Pl. N. and Kenwood Pl. N. meet the lake.

Quite rewarding. I've got to do this more often.

Cheers,
Martin Muller, Seattle
martinmuller at msn.com

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