The adaptive significance of communal nesting in Groove-billed anis (Crotophaga sulcirostris)
- 166 Downloads
A two-year field study of Groove-billed anis was conducted to determine the advantage of communal group nesting versus solitary pair nesting. The following specific hypotheses were tested: a) groups have better territories than pairs; b) groups defend their nests better against predators; c) groups can feed nestlings more efficiently; d) groups can raise more broods per season; e) adult survival is higher in groups.
Large groups (3+ pairs) were found to occur primarily in second growth and marsh portions of the study area, single pairs and small groups primarily in the pastureland areas. Vegetation cover, territory size, and nest height differed significantly in these two habitats, but food abundance during the breeding season was similar. The two habitats were analyzed separately to separate out group size effects and habitat effects.
Groups in the pasture habitat had significantly lower nest predation than pairs, but there was no significant difference in predation rate between groups and pairs in the marsh.
Groups in the pasture were less successful in raising nestlings than pairs, but there was no significant difference in juveniles raised per pair for large and small groups in the marsh.
In both habitats, pairs were more likely to attempt second broods than groups. Second broods were much more frequent in the pasture than in the marsh.
Annual reproductive success (juveniles/pair/year) was the same for all commonly occurring group sizes within each habitat, but was higher in the pasture than in the marsh because of the high frequency of second broods.
In the marsh habitat, adult survival was considerably higher for females and subordinate males than for dominant males, providing a possible incentive for group formation in this habitat. In the pasture, females had slightly lower survival than males. It is hypothesized that the advantage of communal nesting is the reduction of parental care costs, particularly the risk of mortality during incubation.
KeywordsPredation Rate Adult Survival Dominant Male Nest Predation Territory Size
Unable to display preview. Download preview PDF.
- Alvarez, H.: The social system of the green jay in Columbia. Living Bird 14, 5–44 (1975)Google Scholar
- Brown, J.L.: Cooperative breeding and altruistic behavior in the Mexican jay, Aphilocoma ultramarina. Anim. Behav. 18, 366–378 (1970)Google Scholar
- Brown, J.L.: Communal feeding of nestlings in the Mexican jay, Aphilocoma ultramarina: interflock comparisons. Anim. Behav. 20, 395–403 (1972)Google Scholar
- Brown, J.L.: Alternate routes to sociality in jays. Am. Zool. 14, 63–80 (1974)Google Scholar
- Bruning, D.: Social structure and reproductive behavior in the Argentine grey rhea (Rhea americana albescens). Ph. D. Dissertation, University of Colorado, Denver (1974)Google Scholar
- Craig, J.L.: The social organization of the pukeko, Porphyrio porphyrio melanotus, Temminck, 1820. Ph. D. Dissertation, Massey University, New Zealand (1974)Google Scholar
- Davis, D.E.: Social nesting habits of smooth-billed ani. Auk 57, 178–218 (1940)Google Scholar
- Davis, D.E.: Social nesting habits of Crotophaga major. Auk 58, 179–183 (1941)Google Scholar
- Dow, D.D.: Communal behavior of nesting noisy miners. Emu 72, 131–134 (1970)Google Scholar
- Eberhardt, L.L.: Population analysis. In: Wildlife management techniques. Giles, R.H., Jr. (ed.), 3rd ed., Chap. 22. Washington: The Wildlife Society, Inc. 1971Google Scholar
- Fretwell, S.D.: Populations in a seasonal environment. Princeton: Princeton University Press 1972Google Scholar
- Frith, H.J.: Breeding habits in the family Megapodidae. Ibis 98, 620–640 (1956)Google Scholar
- Frith, H.J., Davies, S.J.J.F.: Ecology of the magpie goose, Anseranas semipalmata Latham (Anatidae). CSIRO Wildl. Res. 6, 91–141 (1961)Google Scholar
- Fry, C.H.: The social organization of bee-eaters (Meropidae) and cooperative breeding in hot-climate birds. Ibis 114, 1–14 (1972)Google Scholar
- Gaston, A., Perrins, C.M.: the relation of habitat to size of group in the genus Turdoides. Emu, Suppl, 74, 309 (1975)Google Scholar
- Grimes, L.G.: The occurrence of cooperative breeding behavior in African birds. Ostrich 46, 1–15 (1976)Google Scholar
- Holdridge, L.R.: Life zone ecology. San Jose, Costa Rica: Tropical Science Center 1967Google Scholar
- Kepler, A.K.: Comparative study of todies (Todidae). Nuttall Ornithol. Club 16, 1–190 (1977)Google Scholar
- Köster, F.L. Zum Nistverhalten des Ani. Bonn. Zool. Beitr. 22, 4–27 (1971)Google Scholar
- Lack, D.: Ecological adaptations for breading in birds. London: Chapman and Hall 1968Google Scholar
- Lancaster, D.: Life history of the boucard tinamou in Brit. Honduras. Condor 66, 165–181, 253–276 (1964a)Google Scholar
- Lancaster, D.: Biology of the Brushland tinamou Nothoprocta cinevasans. Bull. Am. Mus. Nat. Hist. 127, 269–314 (1964b)Google Scholar
- Mayfield, H.F.: Suggestions for calculating nest success. Wilson Bull. 87, 456–466 (1975)Google Scholar
- Murdoch, W.W.: The developmental response of predators to change in prey density. Ecology 52, 132–137 (1971)Google Scholar
- Nie, N.H., Hall, C.H., Jenkins, J.G., Steinbrenner, K., Bent, D.A.: Statistical package for the social sciences (SPSS), 2nd ed. New York: McGraw-Hill 1975Google Scholar
- Parry, V.: The auxiliary social system and its effect on territory and breeding in kookaburras. Emu, Suppl., 73, 81–99 (1973)Google Scholar
- Ricklefs, R.E.: An analysis of nesting mortality in birds. Smithsonian Contr. Biol. 9, 1–46 (1969)Google Scholar
- Ridpath, M.G.: The Tasmanian native hen, Tribonyx mortierii; I. Patterns of behavior, II. The individual, the group, and the population, III. Ecology. CSIRO Wildl. Res. 17, 1–51, 53–90, 91–118 (1972)Google Scholar
- Rowley, I.: The life history of the superb blue wren (Malurinae). Emu 64, 251–297 (1965a)Google Scholar
- Rowley, I.: White-winged choughs. Aust. Nat. Hist. 15, 81–85 (1965b)Google Scholar
- Rowley, I.: Cooperative breeding in Australian birds. Proc. Int. Ornithol. Congr. 16, 657–666 (1976)Google Scholar
- Sauer, E.G.F., Sauer, E.M.: The behavior and ecology of the South African ostrich. Living Bird 5, 45–75 (1966)Google Scholar
- Schäfer, E.: Zur Biologie des Steinhuhnes Nothcercus bonapartei. J. Ornithol. 95, 219–232 (1954)Google Scholar
- Service, Jolayne: A user's guide to the statistical analysis system (SAS). Raleigh, N. Carolina: Student supply stores, North Carolina State UniversityGoogle Scholar
- Skutch, A.F.: Life history of the groove-billed ani. Auk 76, 281–317 (1959)Google Scholar
- Smith, S.M.: The relationship of grazing cattle to foraging rate in anis. Auk 88, 876–880 (1971)Google Scholar
- Swainson, G.W.: Cooperative rearing in the bell miner. Emu 70, 183–188 (1970)Google Scholar
- Tinbergen, N., Impekoven, M., Franck, D.: An experiment on spacing-out as a defense against predation. Behaviour 28, 307–321 (1967)Google Scholar
- Vehrencamp, S.L.: Relative fecundity and parental effort in communally nesting anis, Crotophaga sulcirostris. Science 197, 403–405 (1977)Google Scholar
- Vehrencamp, S.L., Stiles, G.F., Bradbury, J.W.: Observations on the foraging behavior and avian prey of the neotropical carnivorous bat, Vampyrum spectrum. J. Mammal. 58, 469–478 (1977)Google Scholar
- Woolfenden, G.E.: Florida Scrub Jay helpers at the nest. Auk 92, 1–15 (1975)Google Scholar
- Woolfenden, G.E.: Cooperative breeding in American birds. Proc. Int. Ornithol. Congr. 16, 674–684 (1976)Google Scholar
- Yom-Tov, Y.: Effect of food and predations on breeding of crows. J. Anim. Ecol. 43, 479–498 (1974)Google Scholar
- Zahavi, A.: Communal nesting by the Arabian babbler: a case of individual selection. Ibis 116, 84–87 (1974)Google Scholar
- Zahavi, A.: Cooperative breeding in Eurasian birds. Proc. Int. Ornithol. Congr. 16, 685–694 (1976)Google Scholar