Along the Alder Trail on the Schoodic Peninsula this past June, perched high in the shrubs and small trees — yes, in the proverbial “catbird seat” — a Gray Catbird sat singing his rambling phrases. As I happily recorded him, I heard the nasal “peent” call of a Common Nighthawk, yet when I looked to the sky where I would expect to see a Common Nighthawk — an acrobatic aeralist — there was none. By the fourth “peent” call, it occured to me that it might be the catbird that was making imitations of the calls of the a Common Nighthawk calls, and my jaw dropped! Could it really be? So, after processing the sound file, and looking at the spectrogram, I took the question to my informal “community of practice.” Here is the discussion that followed.
LS: Very weird and serious inquiry here for my birding friends. Can you listen 3 times? Cause the question needs real good scrutiny and that includes looking at the spectrogram (below). Has this Gray Catbird included a Common Nighthawk “peent” in its repertoire? Seriously. It seems so when looking and listening; but it also seems unbelievable. Is it coincidence? I mean, it – the possible CONI – never overlaps other bird sounds, (like the Song Sparrow, Alder Flycatcher, & Herring Gull). Though of course the call is shorter, the energy level seems about the same, and the spacing too. I need critical opinions with reasons why or why not to help me understand – like, “that kind vocalization would not be possible for a Gray Catbird.” Help, dear friends!
RL: Fine Catbird recording. I suspect the “Nighthawk” peents are only Nighthawk in our imagination, and are just part of the Gray Catbird’s regular repertoire.
LS: Not so sure about that because the spectrogram looks just like the peent calls of the nighthawk, know what I mean? — so, that is, it is not just my imagination that it sounds just like a nighthawk. (I know CONI because in 2017 I looked at every single CONI recording in the Macaulay Library and Xeno Canto as part of research on a unique CONI call).
LS: And I know there are some catbirds that have more extensive repetoires (age/expereince I suspect). So, for instance I remember GB told us about a catbird in Sierra Nevada.
LS: I do see what you mean now RL, as far as whether or not the birds knows it is mimmicing a CONI. Is that what you mean?
BW: Cool. Iʼm not necessarily a Gray Catbird expert, but I canʼt think of any reason why your hunch is not correct.
GB: No you’re not nuts. While they’re not perfect imitations, there is reason to believe that is what they are. I assume you’ve heard the dissection of the Gray Catbird song from Carman Valley, an uncommon bird in California. That individual was a particularly accurate mimic among catbirds.
WH: From the tempo of the phrasing and the fact that there is never an overlap with the “nighthawk,” I would have to say that it is indeed the GRCA mimicking the peent calls of a CONI. Since this individual was recorded where there are a lot of CONIs, I would say it is very likely that he would mimic commonly heard, loud calls from another species. Nice catch getting this recording. It would be interesting to see if these “peents” are found in other GRCA songs from areas where there are no to very few CONIs.
RC: I see no reason to doubt that these nighthawk-like sounds are part of the catbird’s repertoire. The amplitude and temporal relationships with surrounding song elements certainly are consistent with this being part of the catbird’s performance. I know of no reason to doubt that a catbird could make such a sound. As to whether it actually *is* mimicry of a nighthawk—hard to say, as RL suggests, but sounds pretty good to me! And BTW– nice recording!
LS: OH, OH OH!!! a second recording — 7 minutes later shows it again! Will post here as soon as it is processed!
LS: Here is the second recording (below) of the same bird seven minutes later, but further down the trail! These also have calls that look like CONI but I suspect are the catbird again!
BM: The second recording really seems to suggest that this is a gray catbird imitating a CONI. The first CONI sound on this track actually sounds like an imitation because it has a slight blend of other, less CONI-like tones, which Iʼve often found indicative of a less than perfect imitation. Overall, though, if weʼre going with GRCA Iʼd say the singer is a very good imitator! Given the temporal spacing and relatively similar amplitude between the catbird sounds and the CONI sounds, I am also inclined to agree with the statements of other folks on this thread. You already have plenty of expert input of course!
LS: Thanks, BM. In the 2nd recording, I could not see the bird. In the first, I could see the bird sporadically (until it flew away). However, I did not see the birds “lips” move (Ha ha ha! so to speak) when the sounds were being made.
MY: Nice CONI mimicry.
ED: I know I’ve heard NOMO doing that, so I don’t see why GRCA couldn’t.
LG: I’m with other folks. The “CONI” call falls right in the rhythm of the GRCA song, never overlaps, and has the same magnitude. Also, the GRCA song elements before and/or after the CONI are similar in all cases.
LS: THANKS, AGAIN, everyone!
RL: Your supposition is good.
LS: Thanks, RL! I so appreciate your experience and knowledge, without that my supposition has little value.
And, that’s a wrap, a community of practice, albeit informal, in action. Of course, Birds of the World, is a great resource too, but I also truly value the opportunity to discuss mysteries with others.