This forum post came up while doing a general internet search on the St. Vincent Solitaire (Myadestes (genibarbis) sibilans). I thought I’d provide a few thoughts and updates.
I have had some experience with the Jamaican (solitarius) and Hispaniolan (montanus) solitaires- vocally, their songs and calls are similar in structure and complexity, but there are differences - to my ears, the former sounds a little more melodic, with richer, deeper, and more rounded tones; the latter sounds more sibilant, strident, and mechanical with greater use of higher frequencies (there are few examples of solitaires online- the best available are on Bird Songs in Jamaica by Reynard and Sutton. From what I’ve read, montanus is more similar vocally to the birds from Dominica, Martinique, and St. Lucia.
Visually, the Jamaican bird is rather uniformly darker, has a less distinct malar stripe with just 2 small spots of white just below the gape and on the chin, and very faint if any paler streaking on the auriculars. The solitaire on DR is paler especially below, has more white on the chin and on side of throat and shows a distinct dark malar stripe, and shows paler streaking on the auriculars. Montanus is apparently more similar in appearance to the birds from Dominica, Martinique, and St. Lucia. Some good comparison photos of montanus and solitarius are at:
http://www.kingsnake.com/westindian/metazoa17.html
The Jamaican Solitaire was shown to be more distantly related to other populations of the Rufous-throated Solitaire group in:
Miller, M., Bermingham, E., and Ricklefs, R. 2007. Historical Biogeography of the New World Solitaires
(Myadestes Spp.). The Auk 124(3):868–885.
They state “In the case of M. genibarbis, the largest phylogeographic break occurs between the population on Jamaica and populations on Hispaniola, Dominica, Martinique, and St. Lucia (4.1%); the maximum divergence between Hispaniolan and Lesser Antillean populations was 0.9%.” They go on state: “A plausible scenario for the colonization and spread of Myadestes in the West Indies posits the roughly contemporaneous arrival of the lineage in Cuba (M. elisabeth) and either Hispaniola or Jamaica (M. genibarbis). Following a moderately long period of evolutionary independence, M. genibarbis expanded its range to include the second island. Then, well after the initial differentiation of Jamaican and Hispaniolan populations, Myadestes spread from Hispaniola to colonize the Lesser Antilles. The absence of M. genibarbis from Puerto Rico and the northern Lesser Antilles indicates either that former populations on these islands have become extinct, probably within the past 0.5 million years given the relatively low level of differentiation between Hispaniolan and Lesser Antillean populations (<1.0%), or that Myadestes colonized the Lesser Antilles by long-distance dispersal, bypassing these islands. Under either hypothesis, what is clear is that geographic range expansion and long-distance dispersal of Myadestes in the West Indies are transient population phases interspersed by relatively long phases of population differentiation.”
They also state: “Our study revealed significant phylogenetic differentiation below the species level in M. genibarbis and M. ralloides. In the case of M. genibarbis, the deepest phylogeographic break separates the Jamaican population from the rest of the sampled West Indian islands. One taxonomic solution would be to follow Ridgway (1907) and recognize the Jamaican Solitaire, Myadestes solitarius Baird, as specifically distinct from other populations of M. genibarbis.”
Sadly, they did not include sibilans (likely specimen available) nor do they even discuss this form in the text or in their discussion of how the islands may have been colonized which is surprising given that this island population is at least as distinctive as the Jamaican Solitaire and is worthy of mention.
The following paper may be of interest- it is available from the Biodiversity Heritage Library includes a colored plate illustrating the heads of the 6 Rufous-throated Solitaire populations:
Stejneger, L.H. 1882. Synopsis of the West Indian Myadestes. Proceedings of the United States National Museum, Vol.5, pp. 15-27, plate 2.
The specimen of montanus Stejneger had access to may have been a first-year bird, since the bird described and illustrated lacks any white on the chin or below the gape as well as pale streaking on the auriculars. These would all be present in an adult Hispaniolan solitaire.
Niels- Did you happen to get any recordings or photos of the St. Vincent Solitaire- although the bird is well illustrated in several places I can find no photographs (in print or on the internet) and there is but one poor quality recording on the Macaulay Library.
