Saturday, March 21, 1998

White phase Reddish Egret in El Agallito

A white phase Reddish Egret was studied carefully for half an hour at El Agallito beach, Chitré, the first report of that color phase from Panama. Also seen were a flock of Stilt Sandpipers.

    An adult Reddish Egret was studied carefully for half an hour at El Agallito at dusk on Saturday, march 21st by Delicia and Darién Montañez. The observations were made from very short range, and all the fieldmarks could be seen well, eliminating all other possibilities. Even though we are not aware of any previous sightings of white phase Reddish Egrets from Panama, and the fact that it is "unlikely in Panama" (Ridgely, 1989), we are convinced of the accuracy of our identification.
    It was about 6:00 P.M, and the tide was beginning to rise. After walking out to the water’s edge two times to watch a small flock of terns we were exhausted. We were very disappointed there were no Inca Terns, so I said I would settle for any bird new-for-Panama. I was so tired I would settle for a Reddish Egret. Once we got to the building, we stopped for a while to catch our breath before calling for a cab. We sat on the ledge on the outside of the parapet of the "Jardín El Agallito", looking out to sea.
    We first noticed the egret by its strange behavior. It was foraging in a shallow pond not 10 meters away from us, running after small fish. It moved constantly, sometimes opening its wings while on the chase, but stopping every now and then to preen. Since I have seen various species of herons and egrets catch fish this way, I didn’t expect anything totally unusual, but I watched through my binoculars anyway. I was jokingly announcing I was watching a Reddish Egret when I noticed its pink bill. Naturally, we got as close as we could, and watched it as long as we could, but it was getting dark fast, and we had to leave after 30 minutes of close scrutiny. This bird foraged actively and just kept moving, but at all times was closer than 15 meters from us, sometimes getting as close as 4 m. We were using Leica 10x42 and Bushnell 8x42 binoculars and, since the sun was just about to set, the diffuse light provided very good observation conditions.
    When we first saw it, it was all alone in the pond, but after a while a Snowy Egret joined it, and then an adult Tricolored Heron also showed up. Some times we were able to get all three of them on the same field of view, and the differences were evident. This bird was slightly larger than the others, but still smaller than a Great Egret, and looked bulkier overall. Its plumage was completely white, with long plumes on its head, neck and back that gave the bird a shaggy, unkept look. These long plumes were also white, but seemed to have a slight yellowish tinge. The bill was about as long as that of the other egrets, but was stouter, especially at the base. A third of it was dull pink, and the tip was black. The bare facial skin around the eye was greenish yellow, turning grayish-blue on the lores; and its irises were bright yellow. The legs were grayish-black, turning slate-gray on the tibia. Once it flew out of the water, and we could clearly see that its toes were also black. This combination of markings eliminate all of the other similar herons: Great Egrets are larger, and have a bright yellow bill in all plumages.
    The Snowy Egret is smaller, its bill is thinner and all black, and its facial skin and toes are yellow. Immature Little Blue Herons are also smaller, don’t have long plumes, their black-tipped bills are blue-gray, and their legs are greenish-yellow. The only reference to the basic plumage of the Reddish Egret I have found states that "non-breeding adults... have dark bills" (Griggs, 1997). I presume this bird is molting into alternate plumage, thus its bill is not "pink... with a black tip" but black with pink on the base. That would also explain the absence of long plumes on its breast shown on all pictures of breeding adults.
    Early in the morning of Sunday, march 22nd we returned for a second look and to try to get a picture, but the bird was not there. The tide was still going down, and the pond where the egret had been now hosted a solitary Snowy Egret, also running with wings half open. The pond was much larger and deeper now, obviously because of the receding tide. This pond fills a slight depression and always has water on it, but can get very small (and crowded with fish) just before high tide refills it. So maybe the best times to feed, and to find birds, on it is when the tide is rising. This egret would be amazingly easy to overlook, especially from a distance, and visitors to the area should beware that it is chock full of Snowy and Great Egrets, and that both Snowies and Tricolored Herons forage in a ‘drunken’ fashion like the Reddish. Also, there’s a large number of salt and shrimp ponds in the "albinas" right next to the beach, and the egret might prefer to visit any of these spots. And even though these ponds are scattered over a large area, it’s still smaller than the Aguadulce salinas.
    Quotes from:
    Griggs, Jack L. All the birds of North America. 1997.
    Ridgely, Robert S. A guide to the birds of Panama. 2nd edition, 1989.
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    Also seen at El agallito were a flock of 12 Stilt Sandpipers on Saturday. Early on Sunday there were about 50 Stilt Sandpipers roosting in the ponds to the left of the main road. A White-winged Dove perched briefly on the wires on Sunday, and a pair of Common Ground-Doves were seen on the road to Sarigua on Saturday.

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