Question: Vocalizations and Species limits (1 Viewer)

[Mysticete]

Hey folks,

This question has been bugging me for a bit, and I was hoping some folks here might have a better idea of the answer.

We know that for many birds vocalizations are important, and are in fact a key trait that limits interbreeding and thus a good indicator for species status. With of course the caveat that in some species song and calls are quite plastic or are learned.

Obviously however they are important in night birds, songbirds in general, and so forth. My question is, are there specific groups where vocalizations are NOT important? Kind of feels like they don't matter a whole lot to ducks for instance. But I was wondering what other groups would vocalizations not be very helpful?

 

[Jim LeNomenclatoriste]

Corvus corone and Corvus cornix have the same cry, the same for Passer domesticus, hispaniolensis and italiae at first sight.

 

[Mysticete]

In this case I was wondering on a broader, say family or order level. There are of course species pairs and such that are so recently diverged that vocal differences are slight.

 

[lgonz1008]

Some basal bird groups don't seem to have calls matter much into it, waterfowl as you mentioned, but also seems to extend to most ratites (Kiwis being the exception because nocturnal). I'd say parrots also fit into it, since most species have relatively similar calls, tend to be found in different regions and calls to distinguish them only seems to matter when they are in places that were brought in by human intervention (such as all the Psittacara parakeets in South Florida).

 

[jurek]

All songbirds with song dialects, several song types or big individual / geographic variability of song should fit the description. Since one will say that in birds which have huge individual variability of color, color does not matter during breeding, the same reasoning fits all birds with big variability of sounds.

Large gulls were heavily studied why they don't hybridize, and they recognize each other by color of eye and eye-ring. So I guess not by call (although long calls of large gulls are different for every species).

Herons, storks, ibises, cormorants, pelicans, waterfowl, terns, auks I guess. And of course, birds which don't call during courtship, like Ruff and Great Bustard.

 

[Mysticete]

All songbirds with song dialects, several song types or big individual / geographic variability of song should fit the description. Since one will say that in birds which have huge individual variability of color, color does not matter during breeding, the same reasoning fits all birds with big variability of sounds.

Large gulls were heavily studied why they don't hybridize, and they recognize each other by color of eye and eye-ring. So I guess not by call (although long calls of large gulls are different for every species).

Herons, storks, ibises, cormorants, pelicans, waterfowl, terns, auks I guess. And of course, birds which don't call during courtship, like Ruff and Great Bustard.

Yeah I was thinking Gulls after I posted. I never hear people debate the merits of gull call type in the way they do slight plumage variations.

With Gulls and ducks, it's interesting that calls are less important to them and that they also seem to hybridize the most readily with one another. coincidence or correlation?

 

[DMW]

It's an interesting question, and perhaps going off on a slight tangent, I think one of the more remarkable aspects of bird biology is the apparent persistence of songs over long periods of time, even within Passerines. Even long-isolated sedentary populations typically have similar or even very similar songs. It makes me think of songs as almost gene-like in their hereditary nature.

 

[MiddleRiver]

I heard a cool lecture by a researcher in US who has looked at Mockingbirds song in areas where high levels of ambient noise occur. Seems if they can't hear natural sounds well, something is lost in their repertoire. No one really knows long term effects of this noise pollution :-(

 

[MiddleRiver]

It's an interesting question, and perhaps going off on a slight tangent, I think one of the more remarkable aspects of bird biology is the apparent persistence of songs over long periods of time, even within Passerines. Even long-isolated sedentary populations typically have similar or even very similar songs. It makes me think of songs as almost gene-like in their hereditary nature.

But it makes sense if young are learning from parents.
Human accents are learned at early age. I was told by a neurophysiologist that 'accent' and language acquisition is largely determined by age 7 or so in humans (granted this was based on research back in mid 70's when I was in university).
Where we live in VA (US) black caps and carolina chickadees overlap and song specificity is drifting/hybridizing.

 

[DMW]

But it makes sense of young are learning from parents.
Human accents are learned at early age. I was told by a neurophysiologist that 'accent' and language acquisition is largely determined by age 7 or so in humans (granted this was based on research back in mid 70's when I was in university).
Where we live in VA (US) black caps and carolina chickadees overlap and song specificity is drifting/hybridizing.

I'm not saying it doesn't make sense, rather that it's remarkable that learned songs can be passed down through so many generations with such accuracy and, in many cases, so little variation.

 

[pbjosh]

Corvus corone and Corvus cornix have the same cry, the same for Passer domesticus, hispaniolensis and italiae at first sight.

While it is easy to analyze song and call when they are extremely divergent I think it is much harder to analyze when they are very similar. Of course similar song and positive playback response (trials of which are themselves problematic in the extreme) don’t actually mean the birds would interbreed (or if they would, to what degree) though similar songs do admittedly look damning and require more proof if a case is to be made for separation I think in cases of adjoining or fully sympatric similar sounding birds genetics can tell us more than human yardsticking of “sounds the same to me and I played A to B and B responded.” I mean if I yell at my neighbor he understands and responds but I don’t want to make babies with him 🤣

 

[pbjosh]

Some basal bird groups don't seem to have calls matter much into it, waterfowl as you mentioned, but also seems to extend to most ratites (Kiwis being the exception because nocturnal). I'd say parrots also fit into it, since most species have relatively similar calls, tend to be found in different regions and calls to distinguish them only seems to matter when they are in places that were brought in by human intervention (such as all the Psittacara parakeets in South Florida).

There are plenty of cases of sympatric parrots, macaws, and parakeets in the wild that are damned hard / if not impossible to do on call.

 

[pbjosh]

Yeah I was thinking Gulls after I posted. I never hear people debate the merits of gull call type in the way they do slight plumage variations.

With Gulls and ducks, it's interesting that calls are less important to them and that they also seem to hybridize the most readily with one another. coincidence or correlation?

Do we actually know that the calls don’t matter to them?

With ducks at least there is a genetic predisposition to infidelity (all your eggs in one basket is a poor strategy with such high nest failure rates) which presumably leads to cross species breeding.

So a willingness to have exotic partners might not mean that the call isn’t important. For flock migration, say, it could be critical just to speculate.

 

[pbjosh]

It's an interesting question, and perhaps going off on a slight tangent, I think one of the more remarkable aspects of bird biology is the apparent persistence of songs over long periods of time, even within Passerines. Even long-isolated sedentary populations typically have similar or even very similar songs. It makes me think of songs as almost gene-like in their hereditary nature.

I marvel at this also. Things like the (relative) heterogeneity of song in Eurasian Wren (vs extreme wren diversification in New World wrens and the song variation in House Wren), in comparison with something like the Schiffornises (where a recent paper suggests we can double the number of species) which all have recognizably schiffornis songs but where there is very solid song fidelity regionally but more regional diversity than current species limits suggest. Really cool aspects of biology and some taxonomic headaches in there (House Wren again, not to mention Sedge/Grass Wren).

 

[Jon.Bryant]

While it is easy to analyze song and call when they are extremely divergent I think it is much harder to analyze when they are very similar.

This is an interesting point. What we as humans think are similar sounds, may be very different to birds which seem to live (or at least analyse sound on a different time scale). For example a chick Sandwich Tern can recognise its parent voice, whereas I think all Sandwich Terns sound the same, and even suspect I would struggle to find any difference in a sonogram. For the Eurasian Magpie split, I understand the number and spacing of the chack notes was important, but I struggle to count the notes in real time.

I am pretty sure that the courtship call of Gadwall is very distinct from Mallard, and I have never heard of a Gadwall Mallard hybrid, so perhaps even in ducks (where species are visually similar) voice is important.

Gull definitely have different vocals and Merlin easily identifies my flight calls of Yellow-legged Gull. It is just they are not very distinct to mere humans (who often complain of being tone deaf in any case).

 

[Jon.Bryant]

I would also add that many crows are very distinct even to my ears - say Rook and Carrion Crow (and of course Raven - and even Chihuahua Raven seemed unique when I last heard it).

On a tour to PNG the tour guide was very good on parrot vocalisations (very useful for fly-bys) and from my recordings the very experienced Phil Gregory had a good idea of the parrot or parakeet species involved (without of course being able to see the bird in question). And I suspect that now, automated systems (such as Merlin) will outperform even the exceptional hearing of very experienced and amazing individuals.

Are there any birds or families that don’t really vocalise at all, and hence obviously don’t use call for courtship or pair bonding? I can’t think of any off the top of my head (but have a dim feeling that I have read of a species or two that are practically silent).

 

[Jon.Bryant]

Finally corvids are quite interesting. For example Carrion Crow calls can be extremely variable (and very strange at times). Corvids perform well on intelligence test, and it would be interesting to study if these calls have any ‘meaning’. The strange Carrion Crow calls seem to be uttered periodically by birds and are not a dialect.

Chough (another distinct Corvid call) does seem to have very distinct regional dialects - with birds that I recorded in Bhutan recently, very different to the calls I am familiar with in the U.K.

 

[pbjosh]

Getting back to parrots, Jon, my experience is more New World. I struggle tremendously / do not rate my own heard only judgements with the “non blue” large Macaws, with the “standard” Amazons - ie not Yellow-headed/naped/etc, and particularly with Pyrrhura and Touit where there is overlap.

I am very, very far from the best field birder / Neotropic “ear” I know but these are groups where I have seen people who I consider far better than me by ear still make a ton of audio ID errors. Really hard species pairs/groups in there.

 

[Mysticete]

Finally corvids are quite interesting. For example Carrion Crow calls can be extremely variable (and very strange at times). Corvids perform well on intelligence test, and it would be interesting to study if these calls have any ‘meaning’. The strange Carrion Crow calls seem to be uttered periodically by birds and are not a dialect.

Chough (another distinct Corvid call) does seem to have very distinct regional dialects - with birds that I recorded in Bhutan recently, very different to the calls I am familiar with in the U.K.

I can't speak for Carrion Crows, but I want to say there is research done on either/both Ravens and American Crows suggesting that specific calls have specific meaning. Although this is all vague memory so I can't recall how "specific" a call is.

 

[Mysticete]

Getting back to parrots, Jon, my experience is more New World. I struggle tremendously / do not rate my own heard only judgements with the “non blue” large Macaws, with the “standard” Amazons - ie not Yellow-headed/naped/etc, and particularly with Pyrrhura and Touit where there is overlap.

I am very, very far from the best field birder / Neotropic “ear” I know but these are groups where I have seen people who I consider far better than me by ear still make a ton of audio ID errors. Really hard species pairs/groups in there.

I want to say my guide in Ecuador was usually able to ID parrots fly-bys by calls, although that might be in part knowing the expected species for a given site and knowing the basic differences between genera, versus able to sort out ad id a, say specific species of Amazona, by call