Advertisement

Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

The dynamics of parental care in Choughs(Pyrrhocorax pyrrhocorax)

Die Dynamik elterlicher Investition bei der Alpenkrähe(Pyrrhocorax pyrrhocorax)

Summary

The dynamics of parental investment throughout the nestling stage and the factors affecting it were studied in the Chough(Pyrrhocorax pyrrhocorax), a species whose patterns of apportioning parental care are largely unknown. The occurrence of important trade-offs between the sexes, among the different activities of parental care and between parents' survival and current offspring survival were estimated. The parental contributions of both sexes were assessed mainly in terms of food provisioning rate and nest attendance time. Only the female brooded young nestlings while the two sexes contributed equally in food deliveries and nest sanitation. Nestling age greatly affected nest attendance time. The female spent a long time brooding in the first 10 days after hatching. Both sexes increased attendance towards the end of the nestling stage. Conversely, feeding rate and feeding rate per nestling remained approximately constant throughout the nestling period. Nestlings in smaller broods received more feeding visits than those in larger broods. The shape of the per-nestling feeding rate curve was ‚concave-up’, supporting Nur's (1984) ‚trade-offs model’ rather than the Lack-Gibb hypothesis. Maintaining a high feeding frequency in broods already above the modal value might be disadvantageous, implying few benefits and large energy costs (i.e. the reduction of the parents' residual reproductive value). Female brooding time in relation to brood size showed the same decreasing ‚concave-up’ trend line. Short-term trade-offs proved to be important determinants of the dynamics of parental care. Specifically, the distance from the feeding areas greatly affected the delivery rate: pairs spent a disproportionately longer time foraging in more distant patches than in closer ones. Diurnal variations and changes owing to weather conditions were also examined.

Zusammenfassung

Der elterliche Aufwand und die geschlechtliche Verteilung des Brutaufwandes bei Alpenkrähen ist weitgehend unbekannt. Ziel der Arbeit war es deshalb, die verschiedenen Aktivitäten der elterlichen Brutversorgung und deren Konsequenzen für die Überlebensverhältnisse der Eltern und des Nachwuchses näher zu untersuchen. Die Fütterung der Brut und die Anwesenheit und Betreuung am Nest standen im Mittelpunkt. Während nur das Weibchen brütete, teilten sich die Eltern die Jungenaufzucht und die Pflege des Nestes etwa gleichmäßig, wobei das Nestlingsalter einen erheblichen Einfluß auf die Nestversorgung hatte. In den ersten 10 Tagen huderte das Weibchen intensiv. Beide Eltern steigerten ihre Brutpflege zum Ende der Nestlingszeit. Dagegen blieben die Fütterungsrate und die Anzahl Fütterungen je Nestling über die gesamte Nestlingszeit in etwa konstant. Junge in kleineren Bruten erhielten mehr Fütterungen als solche in großen. Der Verlauf der Abhängigkeit der Fütterungen je Nestling von der Brutgröße stützt mehr die Hypothese von Nur (1984) als die von Lack und Gibb. Die Aufrechterhaltung einer hohen Fütterungsrate auch bei großen Bruten dürfte nachteilig sein, da sie nur wenig Nutzen bei einem hohen Aufwand (Beeinträchtigung der späteren Brutmöglichkeiten) bringt. Der Huderaufwand des Weibchens zeigt in etwa denselben Zusammenhang mit der Brutgröße. Kurzzeitige elterliche Entscheidungen scheinen eine wichtige Rolle in der Regulation der elterlichen Brutpflege zu spielen. Dabei kommt gerade der räumlichen Lage der Nahrungsplätze eine große Bedeutung zu: an weiter entfernt gelegenen Nahrungsplätzen verbrachten die Eltern unverhältnismäßig mehr Zeit als an nahen Futterplätzen. Daneben haben die Tageszeit und das Wetter einen Einfluß auf die elterliche Brutfürsorge der Alpenkrähen.

This is a preview of subscription content, log in to check access.

References

  1. Bedard, J. & Meunier, M. (1983): Parental care in the savannah sparrow. Can. J. Zool. 61: 2836–2843.

  2. Biermann, G.C. & Sealy P. (1982): Parental feeding of nestling yellow warblers in relation to brood size and prey availability. Auk 99: 332–341.

  3. Bignal, E. (1994): Chough. In: Tucker G.M. & Heath M.F. (eds.): Birds in Europe, their conservation status. Cambridge.

  4. Bignal, E.M. & Curtis, D.J. 1989: Choughs and land-use in Europe. Clachan, U.K.

  5. Bignal, E.M., McCracken, D.I., Stillman, R.A. & Ovenden, G.N. (1996): Feeding behaviour of nestling Choughs in the Scottish Hebrides. J. Field Ornithol. 67: 25–43.

  6. Bryant, D.M. & Gardiner, A. (1979): Energetic growth in House MartinsDelichon urbica. J. Zool., London 189: 275–304.

  7. Buitron, D. (1988): Female and male specialization in parental care and its consequences in black-billed magpies. Condor 90: 29–39.

  8. Conrad, K.F. & Robertson, R.J. (1993): Brood size and the cost of provisioning nestling. Interpreting Lack's hypothesis. Oecologia 96: 290–292.

  9. Coombs, F. (1978): The Crows. A study of the Corvids of Europe. London.

  10. Drent, R.H. & Daan, S. (1980): The prudent parent: energetic adjustments in avian breeding. Ardea 68: 225–252.

  11. Gibb, J.A. (1950): The breeding biology of the great and blue tit. Ibis 92: 507–539.

  12. Gibb, J.A. (1955): Feeding rates of great tits. British Birds 48: 49–58.

  13. Goodburn, S.F. (1991): Territory quality or bird quality? Factors determining breeding success in the MagpiePica pica. Ibis 133: 85–90.

  14. Goodwin, D. (1986): Crows of the world. London.

  15. Grundel, R. (1987): Determinants of nestling feeding rates and parental investment in the mountain Chickadee. Condor 83: 319–328.

  16. Högstedt, G. (1981): Effect of additional food on reproductive success in the Magpie(Pica pica L.). J. Anim. Ecol. 50: 219–229.

  17. Holyoak, D. (1972): Behaviour and Ecology of the Chough and the Alpine Chough. Bird Study 19: 215–227.

  18. Husby, M. (1986): On the adaptive value of brood reduction in birds: experiments with the magpiePica pica. J. Anim. Ecol. 55: 75–83.

  19. Kacelnik, A. (1984): Central place foraging in starlings(Sturnus vulgaris). I. Patch residence time. J. Anim. Ecol. 53: 283–299.

  20. Kacelnik A. & Houston, A.I. (1984): Some effects of energy costs on foraging strategies. Anim. Behav. 32: 609–614.

  21. Klomp, H. (1970): The determinants of clutch size in birds: a review. Ardea 58: 1–124.

  22. Lack, D. (1947): The significance of clutch-size. Ibis 89: 302–352.

  23. Lack, D. (1954): The natural regulation of animal numbers. Oxford.

  24. Montgomerie, R.D. & Weatherhead, P.J. (1988): Risks and rewards of nest defence by parent birds. Quat. Rev. Biol. 63: 167–187.

  25. Mugaas, J.N. & King, J.R. (1981): Annual variation of daily energy expenditure by the Black-billed Magpie. A study of thermal and behavioral energetics. Stud. Avian Biology No 5.

  26. Nur, N. (1981): The adaptive significance of brood size in the blue tit Parus caeruleus. Ph.D. thesis, Duke University.

  27. Nur, N. (1984): Feeding frequencies of nestling blue tits(Parus caeruleus): costs, benefits and a model of optimal feeding frequency. Oecologia 65: 125–137.

  28. O'Connor, R.J. (1975): The influence of brood size upon metabolic rate and body temperature in nestling blue titsParus caeruleus and house sparrowsPasser domesticus. J. Zool., London 175: 391–403.

  29. Redondo, T. & Carranza, J. (1989): Offspring reproductive value and nest defence in magpie(Pica pica). Behav. Ecol. Sociobiol. 25: 369–378.

  30. Ricklefs, R.E. (1968): Patterns of growth in birds. Ibis 110: 419–451.

  31. Royama, T. (1966): Factors governing feeding rate, food requirement and brood size of nestling great titsParus major. Ibis 108: 313–347.

  32. Rytkönen, S., Koivula, K. & Orell, M. (1996): Patterns of per-brood and per-offspring provisioning effort in the willow titParus montanus. J. Avian Biol. 27: 21–30.

  33. Tinbergen, J. (1981): Foraging decisions in starlings. Ardea 69: 1–67.

  34. Trivers, R.L. (1972): Parental investment and sexual selection. In: B. Campbell (ed.): Sexual selection and the descent of man: 136–179. Chicago.

  35. Wittacker, I. (1947): Notes on Welsh Choughs. British Birds 40: 265–266.

  36. Wittenberger, J.F. (1982): Factors affecting how male and female Bobolinks apportion parental investments. Condor 84: 22–39.

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Laiolo, P., Bignal, E.M. & Patterson, I.J. The dynamics of parental care in Choughs(Pyrrhocorax pyrrhocorax) . J Ornithol 139, 297–305 (1998). https://doi.org/10.1007/BF01653340

Download citation

Key words

  • parental investment
  • feeding rate
  • brood size
  • Lack-Gibb model
  • Nur model