Mystery Hummer Purveys Perplexity / July 2000

Vol. 1, No. 2 July 2000
Mystery Hummer Purveys Perplexity

Back in early January, when Alex Villegas e-mailed the results of the 1999 Monteverde Christmas Bird Count, a mental red flag was quickly hoisted as I read the words: Blue-tailed Hummingbird.

This species (Amazilia cyanura) is included in A Guide to the Birds of Costa Rica based on Paul Slud's 1958 sighting at La Selva and "a specimen taken October 1904 near San José." Its normal range extends from southern Mexico to southern Nicaragua and it is considered accidental in Costa Rica.

Alex was off on tour when I read the CBC results, but I checked with Julio Sánchez to see if he had heard of the sighting. He hadn't, but it turned out that there was a report of this species from 1998 by Jay VanderGaast who observed and photographed an individual at the Hummingbird Gallery feeders in Monteverde. My curiosity more or less satisfied by this bit of information, I left it at that . . . until I happened to be going through some of my own slides in April.

In July 1994, I had taken a number of hummingbird photos at the aforementioned gallery and had labeled two of them "Stripe-tailed Hummingbird" based on the large rufous patches in the wings. At the time, Blue-tailed Hummingbird never crossed my mind as a possibility. However, while sorting through the slides and looking at them with a hand lens, I realized that the bird in my two photos had a decidedly steely blue-black tail and in one of the photos its wings and tail are spread with no white showing in the rectrices! Had I photographed a blue-tail without realizing it?!

I took the slides to the National Museum to show Julio Sánchez. The museum doesn't have any skins of A. cyanura, but we compared my photographed individual with all of the male Stripe-tailed Hummingbird (Eupherusa eximia) specimens -- none of which showed any hint of blue in the tail. We examined them under both the fluorescent lighting of the laboratory and natural lighting and the black tail feathers showed only coppery-green tinges, never blue. Still, since the species in question is so rare in Costa Rica and the white in a stripe-tail is not necessarily obvious from a dorsal view of the tail, there was a lingering doubt as to the identity of the bird in my photos.

On June 30, I was in Monteverde and had a good, long, close-up look at several of the Stripe-tailed Hummingbirds that were at the Hummingbird Gallery feeders. Again, no trace of blue in the tails. Coincidentally, I ran into Leonardo Chaves who was also staying at the Hotel Fonda Vela and he mentioned having seen at least one individual that appears to have a bluish tail, but definitely has all the white coloration of a typical stripe-tail. [Ever since hearing of VanderGaast's sighting, Leonardo has been closely scrutinizing the feeder visitors each time he goes to Monteverde.] That tidbit only added more uncertainty to the identity issue.

As it turned out, the Blue-tailed Hummingbird that was reported for the Monteverde CBC wasn't seen at those feeders, but rather was sighted by the bridge beyond Guacimal (on the road coming up from Sardinal) by Gary Diller and Toby Wallace. Gary also told me that he saw this species in 1989 at Palo Verde while birding with Mike Tidwell from Fresno, CA. Alex Villegas likewise confided that he thought he had seen a Blue-tailed Hummingbird while birding along the ox-bow lake road in Carara some years back, but given the rarity of the bird wasn't sure if that could really be what they were looking at (even though they had a scope view of a perched bird).

This echoes my dilemma in calling the bird in my photos a Blue-tailed Hummingbird. It also makes me wonder how often one might have actually seen a rare species but simply glossed over it assuming it to be a far more common, similar species?!

Male Prairie Warbler Makes Visit to Monteverde

Early this year, a handsome male Prairie Warbler (Dendroica discolor) could be found regularly feeding on cooked rice put out to attract agoutis and other wildlife at the Monteverde Cloud Forest Lodge. This species normally winters from Florida through the West Indies, but occasional individuals are known to stray into various parts of Central America. The bird that wintered in Monteverde was no doubt a lifer for many who were fortunate enough to get to view it. According to Leonardo Chaves' field notes, he first was informed of and saw it in late January. When speaking recently by phone with Alex Villegas, he mentioned the bird being there in March. Having visited Monteverde in mid-February, it's saddening to think that word of this species never reached me until May or June. This problem underscores the need for a more efficient "hot-line" method than the casual word-of-mouth system that exists here in Costa Rica.

Charlie Checks In With Choice Info

After not having seen Charlie Gómez in years, we ran into each other at La Virgen del Socorro on April 8. The children and I were birding with Winnie Orcutt, Ron Boyd, and some friends and were on our way back up the track after a good morning -- although we hadn't found the Lanceolated Monklet (Micromonacha lanceolata) we'd been hoping to see along the forest trail just before the bridge where Winnie had had one several weeks earlier -- when we encountered Charlie and two other birders on their way down the dirt road.

Following the usual pleasantries, Charlie told us of a pair of Tiny Hawks (Accipiter superciliosus) that were nesting just outside the La Selva gate. He also reported seeing two Red-throated Caracaras (Daptrius americanus) in the forest at La Selva -- a great sighting indeed since, as there have been no observations in recent years, this species had been thought to be extirpated from the area!

They also had good fortune during their visit to Selva Bananito Lodge logging a total of four Great Jacamars (Jacamerops aurea)! And likewise, along the Río Tuis above Rancho Naturalista they got to see a Lanceolated Monklet.

This chance meeting led to a lengthy telephone conversation about a week later in which Charlie mentioned two interesting sightings from earlier in the year: Wedge-tailed Grass-Finch (Emberizoides herbicola) and Bay-winged Hawk (Parabuteo unicinctus), both at Isla Damas just north of Quepos. The former represents a significant northward extension of the species' limited distribution in southwestern Costa Rica, and the latter is a sighting a bit further south than this raptor is usually found within the country (i.e., Carara).

Follow-up notes: The boys and I drove down to La Selva that same afternoon to check the Tiny Hawk nest. It was about 100 meters off to the left, across a field from the entrance to La Selva, and consisted of a fairly substantial mass of sticks, at least 30 cm. wide (estimated relative to the size of the adult birds at the nest) and 10 cm. high, situated at the very top of a nearly leafless tree perhaps some 20 to 25 meters tall. The nest construction seemed similar to the one previous Tiny Hawk nest I had seen about 12 years ago in Tortuguero, but the exposed placement differed from the other nest which had been built high among the leafy branches of a "Cativo" tree (Prioria copaifera) located at the edge of evergreen forest.

Through the telescope (20x) we could see each of the adults when they visited the nest, but were unable to observe the nestlings. When I returned a week later with Paul Coopmans and the April Birdquest tour group, we never saw any activity at the nest during two hours of birding the area by the gate. In a recent visit to La Selva (June 26 - 28), Joel Alvarado, a resident station naturalist, told me that no one actually knew if the young fledged successfully or not. He did say that he, too, had seen the pair of Red-throated Caracaras not far out on the Three Rivers Trail (STR) about a week after Charlie Gómez had "re-discovered" them.

Western Slaty-Antshrike Update

My mention of Western Slaty-Antshrike (Thamnophilus atrinucha) in the previous newsletter got some response. Paul Murgatroyd reported also seeing this species in Santa Rosa when he visited there in December 1999. And Keith Taylor obligingly added that, "Although not in literature, it has also been recorded at Palo Verde and near Skutch's." On two separate occasions some ten years ago, I thought I saw this species at Carara, but again going back to the that-species-shouldn't-be-here syndrome, I was reluctant to believe that the birds were really Western Slaty-Antshrikes (though I don't know what else they could have been). The looks were fairly brief and the birds were amidst vines or foliage, but they didn't appear to be Dusky Antbirds (Cercomacra tyrannina) or White-winged Becards (Pachyramphus polychopterus), the two most closely patterned species that are common at Carara.

Anyone else out there have anything to add regarding the Pacific slope whereabouts of this species in Costa Rica?

And Speaking of Whereabouts . . . What About Those Invaders from the South?

Keith Taylor also inquired about the status of Veraguan Mango (Anthracothorax veraguensis) in southwestern Costa Rica since it is included on the bird list put out by the Asociación Ornitológica de Costa Rica (AOCR) and also on the one I have on my website. Good question. Knowing of no country reports for this species, I checked with Julio Sánchez, but he wasn't aware of any sightings here either (confirmed or otherwise). Perhaps at present this mango should best be considered hypothetical for Costa Rica.

That question got me to wondering about the status of several other species suspected of sooner or later working their way up here from neighboring Panama. Here's what Julio told me:

Apparently there have been sightings of two species mentioned in the field guide as good candidates for range expansions into Costa Rica: Sapphire-throated Hummingbird (Lepidopyga coeruleogularis) and Savanna Hawk (Buteogallus meridionalis), however, both need confirmation.

On the Caribbean side of the country, Wing-banded Antbirds (Myrmornis torquata) have been reported by several observers at Rara Avis within the last year or so. And a Swallow Tanager (Tersina viridis) was photographed at Caño Palma Biological Station near Tortuguero a few years back, and also supposedly seen close to the Panama border (Gandoca?).

Paul Coopmans sent this note about Red-breasted Blackbird (Sturnella militaris): "Just doing Panama tour report, and noticed in the field guide that at the time of the latter's going to press, there apparently were no records yet for Bocas del Toro, where we saw it right near Chiriqui Grande. I just wondered if there are any records for Caribbean Costa Rica yet.

"Just heard from George Angher this species was seen near Changuinola in 1995, so I'd be very surprised if by now - 5 years later - it would not yet be present in the Sixaola area."

Actually, yes, there is one report of this icterid on the Caribbean side of Costa Rica. In October 1998, Hernán Araya saw a compact group of more than 40 birds, including adults, juveniles and apparently one albino, foraging in a swampy field east of El Carmen de Siquirres. [Published in V.3, N.1 of ZELEDONIA, the bulletin of the AOCR.] Was this a post-migratory movement, or has the Red-breasted Blackbird now established itself on the Atlantic side of the country?

Paul also made the following mention of Yellow-headed Caracara (Milvago chimachima): "This is another one I recently saw right near Chiriqui Grande in Panama, so I guess you can expect this one to reach Caribbean Costa Rica pretty soon."

As far as I know, we're still waiting, but I have seen this species in the western end of the Central Valley. My first record was of a pair of birds at the I.C.E. catchment pond in San Miguel de Turrucares during the December 1996 Grecia CBC. We also found them there in September and December 1998. Another recent sighting was in October 1999 at El Rodeo.

Two Potential New Country Records

The Clapper Rail (Rallus longirostris) sighting that was reported in the first newsletter remains unconfirmed. A group of North American birders, including Bob Fisher, saw this species at the edge of mangroves along the Gulf of Nicoya near Costa de Pájaros. Apparently, everyone got good looks, but no one had a camera with them -- even Bob, who usually takes his camera everywhere! Julio Sánchez later went looking for it, but without success.

Giovanni Bello reports having seen a Swallow-tailed Gull (Creagrus furcatus) off Golfito while working aboard the M/V Temptress. He's seen it following the ship at night on two occasions now, but no one has taken any photographs.

Cocos Island Trip Still in the Works

How would you like to be able to say that you've seen several birds that Phoebe Ssinger never saw? Well, a trip out to Cocos Island would be one way to go about it. (Phoebe was planning on visiting Cocos with Paul Coopmans in April, had it not been for her tragic death in Madagascar late last year.)

Finally, I want to say how truly gratifying it was to receive so many kind comments from readers of the first newsletter, even my own sister, who's not a birder, said she liked it! And not one person used the "reply" option to remove themselves from the mailing list (just too polite?).

If I can just take a moment to toot my own horn, there was a nice article about the family's interest in birdwatching that appeared in a Sunday supplement of the La Nación newspaper back in May. Anyone interested in reading the story (in Spanish) can access the online version here.

I hope that you've enjoyed this newsletter and welcome any comments at gonebirding@lycos.com or if you're in Costa Rica, feel free to give me a ring at 293-2710.

Wishing you all great birding,

Richard Garrigues

http://www.angelfire.com/bc/gonebirding/index.html