Limits...
Chick Begging Calls Reflect Degree of Hunger in Three Auk Species (Charadriiformes: Alcidae).

Klenova AV - PLoS ONE (2015)

Bottom Line: I found that almost all measured acoustic variables contain information about the chick's state in all studied species.The effect of food deprivation on most acoustic variables exceeded both the effects of individuality and species.As parents do not need to check individuality of the chick in the burrow, which they find visually during the day time, the chicks could use all of the acoustic variables to communicate about their nutritional needs.

View Article: PubMed Central - PubMed

Affiliation: Department of Vertebrate Zoology, Faculty of Biology, Lomonosov Moscow State University, Vorobievy Gory, 1/12, Moscow, 119234, Russia.

ABSTRACT
Begging behaviour is an important element in the parent-offspring conflict; it has been studied in many avian species. However, the majority of the studies have been entirely based on the call counts, and they agreed that vocal activity was a good indicator of chick's nutritional need and/or condition. Fewer researches were dedicated to the temporal-frequency variables of the begging calls themselves and they showed contrary results. Here begging behaviour in three burrow nested, uniparous species of auks (Alcidae) was studied. These objects provide an opportunity to study the signalling value of begging calls in the absence of important confounding factors such as nestling competition and predation pressure. I recorded calls of individual chicks in two conditions: during natural feeding and after experimental four-hour food deprivation. I found that almost all measured acoustic variables contain information about the chick's state in all studied species. The hungry chicks produced calls higher in fundamental frequency and power variables and at higher calling rate compared to naturally feeding chicks. The effect of food deprivation on most acoustic variables exceeded both the effects of individuality and species. In all studied species, the frequency variables were stronger affected by hunger than the calling rate and call durations. I suppose that such strong change of acoustic variables after food deprivation can be explained by absence of vocal individual identification in these birds. As parents do not need to check individuality of the chick in the burrow, which they find visually during the day time, the chicks could use all of the acoustic variables to communicate about their nutritional needs.

No MeSH data available.


Related in: MedlinePlus

Spectrograms of calls in the vocal repertoires of auk chicks.(A) calls of crested auklet chicks, (B) chirp and weep calls of parakeet auklet chicks and (C) chirp and weep calls of horned puffin chicks. Spectrograms were created with a 1024-point FFT, Hamming window, frame 25% and 98.43% overlap.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4633236&req=5

pone.0140151.g001: Spectrograms of calls in the vocal repertoires of auk chicks.(A) calls of crested auklet chicks, (B) chirp and weep calls of parakeet auklet chicks and (C) chirp and weep calls of horned puffin chicks. Spectrograms were created with a 1024-point FFT, Hamming window, frame 25% and 98.43% overlap.

Mentions: According to visual inspection of spectrograms of chick calls, I recognized two main call types in the vocal repertoires of parakeet auklet and horned puffin chicks, and one highly variable call type in crested auklet chicks (Fig 1); [30]. Chirp calls of parakeet auklet and horned puffin chicks were brief, usually uttered rapidly and rhythmically in series, and their spectrograms had the appearance of an inverted U; weep calls were more than three times longer than chirp calls and were given at irregular intervals, sometimes interspersed with series of chirp calls. Weep calls of parakeet auklet and horned puffin chicks were modulated in frequency only slightly. In the vocal repertoire of crested auklet chicks, extremes of brief and long calls resembled chirp and weep calls (respectively) of the other species, but they simply defined the end points of a continuum, and could not be considered as two distinct call types (Fig 1); [30]. Chirp and weep calls of my study species are similar to brief “peep” and long “screech” calls reported for chicks of the Atlantic puffin (Fratercula arctica) [26] and brief “chirp” and long “peep” calls of chicks of the rhinoceros auklet (Cerorhinca monocerata) [9]. Both chirp and weep calls occurred in all recordings.


Chick Begging Calls Reflect Degree of Hunger in Three Auk Species (Charadriiformes: Alcidae).

Klenova AV - PLoS ONE (2015)

Spectrograms of calls in the vocal repertoires of auk chicks.(A) calls of crested auklet chicks, (B) chirp and weep calls of parakeet auklet chicks and (C) chirp and weep calls of horned puffin chicks. Spectrograms were created with a 1024-point FFT, Hamming window, frame 25% and 98.43% overlap.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4633236&req=5

pone.0140151.g001: Spectrograms of calls in the vocal repertoires of auk chicks.(A) calls of crested auklet chicks, (B) chirp and weep calls of parakeet auklet chicks and (C) chirp and weep calls of horned puffin chicks. Spectrograms were created with a 1024-point FFT, Hamming window, frame 25% and 98.43% overlap.
Mentions: According to visual inspection of spectrograms of chick calls, I recognized two main call types in the vocal repertoires of parakeet auklet and horned puffin chicks, and one highly variable call type in crested auklet chicks (Fig 1); [30]. Chirp calls of parakeet auklet and horned puffin chicks were brief, usually uttered rapidly and rhythmically in series, and their spectrograms had the appearance of an inverted U; weep calls were more than three times longer than chirp calls and were given at irregular intervals, sometimes interspersed with series of chirp calls. Weep calls of parakeet auklet and horned puffin chicks were modulated in frequency only slightly. In the vocal repertoire of crested auklet chicks, extremes of brief and long calls resembled chirp and weep calls (respectively) of the other species, but they simply defined the end points of a continuum, and could not be considered as two distinct call types (Fig 1); [30]. Chirp and weep calls of my study species are similar to brief “peep” and long “screech” calls reported for chicks of the Atlantic puffin (Fratercula arctica) [26] and brief “chirp” and long “peep” calls of chicks of the rhinoceros auklet (Cerorhinca monocerata) [9]. Both chirp and weep calls occurred in all recordings.

Bottom Line: I found that almost all measured acoustic variables contain information about the chick's state in all studied species.The effect of food deprivation on most acoustic variables exceeded both the effects of individuality and species.As parents do not need to check individuality of the chick in the burrow, which they find visually during the day time, the chicks could use all of the acoustic variables to communicate about their nutritional needs.

View Article: PubMed Central - PubMed

Affiliation: Department of Vertebrate Zoology, Faculty of Biology, Lomonosov Moscow State University, Vorobievy Gory, 1/12, Moscow, 119234, Russia.

ABSTRACT
Begging behaviour is an important element in the parent-offspring conflict; it has been studied in many avian species. However, the majority of the studies have been entirely based on the call counts, and they agreed that vocal activity was a good indicator of chick's nutritional need and/or condition. Fewer researches were dedicated to the temporal-frequency variables of the begging calls themselves and they showed contrary results. Here begging behaviour in three burrow nested, uniparous species of auks (Alcidae) was studied. These objects provide an opportunity to study the signalling value of begging calls in the absence of important confounding factors such as nestling competition and predation pressure. I recorded calls of individual chicks in two conditions: during natural feeding and after experimental four-hour food deprivation. I found that almost all measured acoustic variables contain information about the chick's state in all studied species. The hungry chicks produced calls higher in fundamental frequency and power variables and at higher calling rate compared to naturally feeding chicks. The effect of food deprivation on most acoustic variables exceeded both the effects of individuality and species. In all studied species, the frequency variables were stronger affected by hunger than the calling rate and call durations. I suppose that such strong change of acoustic variables after food deprivation can be explained by absence of vocal individual identification in these birds. As parents do not need to check individuality of the chick in the burrow, which they find visually during the day time, the chicks could use all of the acoustic variables to communicate about their nutritional needs.

No MeSH data available.


Related in: MedlinePlus