Tepui Wren (Troglodytes rufulus) vocalizations
The Tepui Wren is a poorly known species in the genus Troglodytes found only on remote Tepuis in Venezuela, Brazil, and Guyana. Since it is one of the few tepui specialties that does not occur on the easily accessible and frequently birded Sierra de Lema in Southeastern Venezuela, it has been seen by very few birders, and relatively little is known about its vocalizations.
The most frequently referenced vocaliztion of Tepui Wren is described in Hilty as "a ser. of high, thin, silvery notes delivered in a slow, choppy manner, slick . . seeleet, . . seet . . slick . . t'slick . . slick . . seeleet . .", while Handbook of the Birds of the World (HBW) describes it as "a series of high, thin whistled twitters, sometimes continued for several seconds, sometimes disjunct separate phrases". Birds of Northern South America (BoNSA) says the calls are unknown.
While on a trek to Cerro Roraima in southeastern Venezuela during the summer of 2008 I observed and recorded a number of Tepui Wrens. Here I will describe the several different types of vocalizations I obtained from them, some of which are apparently not described elsewhere.
Simple Song
This is the song of disjunct phrases described in Hilty and HBW. Far an away this was the most frequently heard vocalization from Tepui Wren during the time I spent with them, and functions, I believe, as their primary territorial song. When singing it birds were usually high up in short shrubs (which nonetheless was the tallest vegetation at most the sites where I saw the species). Response to playback of the song was usually immediate and aggressive.
04-07-2008 Cerro Roraima, Bolivar, Venezuela © Andrew Spencer
Among the birds I recorded this song was made up of two different phrases, given in a random pattern. In every bird I recorded one of the phrases was sometimes repeated, in some cases for many times in a row, but the other was never repeated. Below, for example, are four different individuals I record, in which "B" is the phrase sometimes repeated, and "A" is the one never repeated:
Bird 1:
ABABABABBA BABBABBBAB ABBBBABBAB BBABBBBABA BABABBBABB A
Bird 2:
BBABABBABB BBABABABBB BBBBABBABB ABBBBBABBB BBABBBABAB ABBBBB
Bird 3:
BBBBBBABBB BBABABBBBB BBBBBBBBBB BBB
Bird 4:
ABABABBABA BABABBABAB AB
02-07-2008 Cerro Roraima base camp, Bolivar, Venezuela © Andrew Spencer
The song of this species is rather unlike the songs of other members of the genus Troglodytes (at least the ones I have access to recordings of) in that it has much shorter phrases (but see below), and is "choppier" in overall sound.
Complex Song
I heard this vocalization relatively rarely from birds on Roraima. Most often it seemed to be given in agitated situations - I heard birds doing it in response to playback by me, in response to me being close to a juvenile bird, and in response to a conspecific nearby. I also heard it a couple of times without any apparent aggressor nearby.
02-07-2008 Cerro Roraima base camp, Bolivar, Venezuela © Andrew Spencer
This sound is of a lower amplitude than the primary song, slightly higher pitched overall, and much faster and run together. In this final characteristic it is more like the songs of other members of the genus Troglodytes.
All the birds I recorded giving the complex song, except for the one mentioned in the possible song duet below, interspersed the complex song with shorter song phrases, or just switched entirely to the simple song.
02-07-2008 Cerro Roraima base camp, Bolivar, Venezuela © Andrew Spencer
I once heard a pair of birds giving what could be a duet, where one bird was giving the primary song, and another on the other side of me giving the complex song. I watched these same two birds interacting immediately after the singing bout, and they did not appear to be behaving as neighboring males, but more as a breeding pair of bird. While I am not absolutely certain that what they were doing was a song duet, it seems like a plausible explanation.
Calls
I also managed to record at least three types of calls from Tepui Wrens on Roraima. I only heard two birds giving calls, and I think that this species calls relatively rarely compared to other members of the genus. Even when responding to playback, pishing, and even in the company of dependant juveniles, they would mostly not call.
The two birds I did record calling were (I think) near a juvenile or nests; both were seen carrying food. As such I think the calls I recorded from them were highly agitated calls.
There is also a single recording of a calling bird from Guyana on the Macaulay Library website (this is also the only recording of this species available on the web other than my own) that matches the first call type described below.
ML124922 11/04/2001, Guyana, recorded by Brian O'Shea
What I think is the primary call note of Tepui Wren is a fairly low pitched, rough "tchik", given singly or in a short series as a chatter. I only recorded a couple of these calls from one bird, but the ML cut is a series of this call type without any other vocalization. This call is quite similar to the primary calls of several other species of Troglodytes.
04-07-2008 Cerro Roraima, Bolivar, Venezuela © Andrew Spencer
A second call type recorded was a variable length, but longer, high bandwidth (=raspy) call. Aspects of this call (such as duration, pitch change) were variable, but as a whole it sounds very similar to the alarm calls of several other Troglodytes species, somewhat higher pitched than the analogous call in House Wren, but somewhat lower pitched than in Mountain Wren.
04-07-2008 Cerro Roraima, Bolivar, Venezuela © Andrew Spencer
The final call type I recorded may just be a variation on the one above. It had a couple of rather high-pitched (compared to the two calls above) short tinkling notes followed by a shorter, clipped version of the harsh alarm call. The bird giving these calls interspersed them with some of the complex song phrases, a couple of simple song phrases, and some of the harsh alarm calls described above.
04-07-2008 Cerro Roraima, Bolivar, Venezuela © Andrew Spencer
Both birds I recorded calling mixed their calls with complex song, and a couple of simple song phrases. ML# 134922 on the other hand is just a series of call notes; I suspect that the highly agitated state of birds I recorded accounts for the wide variety of call types and mixing with song that I recorded.
04-07-2008 Cerro Roraima, Bolivar, Venezuela © Andrew Spencer
Note on the plumage of this species
The illustration of Tepui Wren in Hilty does not match what the birds actually looked like on Roraima. While it may match one of the multitude of other subspecies of Tepui Wren, the ones on Roraima were clearly grayish breasted, not entirely rufescent as per Hilty. BoNSA does not illustrate the nominate subspecies; the ones on Roraima looked most like the wetmorei illustration in the book, though with slightly less extensive and slightly paler gray on the underparts.
We also observed a few juvenile birds on the Tepui. They did not match the illustrations of juveniles in BoNSA, rather they were uniformly dark brown with no scaling apparent. You can see a poor picture of a juvenile taken on our trek to Roraima here. They all appeared to be older juveniles, though, so I don't know how that affected the plumage we observed.