250 
THE WILSON JOURNAL OF ORNITHOLOGY • Vol 123, No. 2, June 2011 
Capelli, A. M. and A. M. Campo. 2004. Climatologfa. 
Pages 79-86 in Ecosistema del estuario de Bahia 
Blanca (M. C Piccolo and M. S. Hoffmeyer, Editors). 
Second Edition. Instituto Argentino de Oceanograffa, 
Bahia Blanca. Buenos Aires, Argentina. 
Christians, I K. 2002. Avian egg size: variation within 
species and inflexibility within individuals. Biological 
Reviews 77:1-26. 
Crawi ey. M. J. 2007. The R book. John Wiley and Sons 
Ltd.. West Sussex, Lhiited Kingdom. 
Delhey. J K. V., p. F. Petracct. and C. M. Grassini. 
2001. Hallazgo de una nueva colonia de Gaviota de 
Olrog (Lams atlanlicus) en la ria dc Bahia Blanca. 
Argentina. Homero 16:39-42. 
Devili-ER.s, P. 1977, Observations at a breeding colony of 
Lams (belcheri ) atlanlicus. Le Gcrfaut 67:254-265. 
Dexheimer. M. and W, E. Southern. 1974. Breeding 
success relative to nest location and density in Ring¬ 
billed Gull colonics. Wilson Bulletin 86:288-290. 
Falconer. D. S. 1981, Introduction to quantitative 
genetics. Second Edition. Longman Press, London. 
United Kingdom. 
Fetteri.of. P. M. 1983. Effects of investigator activity on 
Ring- hilled Gull behavior and reproductive perfor¬ 
mance, Wilson Bulletin 95:23-41. 
Garcia Borboroolu, P. and P. Yorio. 2007a. Breeding 
habitat requirements and selection by Olrog's Gull 
(Lams atlanlicus ), a threatened species. Auk 124: 
1201 - 1212 . 
Garcia Borboroolu, P. and P. Yorio. 2007b. Compar¬ 
ative habitat use by syntopic Kelp Gulls (Larus 
dominicanus) and Olrog’s Gulls (L. atlanlicus) in 
coastal Patagonia. Emu 107:321-326. 
Graves. J., A. Whiten, and P. Henzi. 1984. Why does the 
Herring Gull lay three eggs? Animal Behaviour 
32:798-805. 
Lack, D. 1968. Ecological adaptations for breeding in 
birds. Chapman and Hall, London, United Kingdom. 
La Sala, L. F. and S. R. Martorelli. 2010. First report of 
Olrog’s Gull depredation by sympatric Kelp Gulls. 
Wilson Journal of Ornithology 122:188-189. 
Magrath. R. D. 1992. Roles of egg mass and incubation 
pattern in establishment of hatching hierarchies in the 
Blackbird (Turdus memla). Auk 109:474-487. 
McGraw, K. and S. P. Wong. 1992. A common language 
effect size statistic. Psychological Bulletin 111:361-365. 
Mills. E. H. 1979. Factors affecting the egg size of Red¬ 
billed Gulls Lams novaehoUandiue scopulinus. Ibis 
121:53-67. 
Nakagawa, S. 2004. A farewell to Bonferroni: the 
problems of low statistical power and publication 
bias. Behavioral Ecology 15:1044-1045. 
Olrog, C. C. 1958. Notas omitcMogicas sobre la colcccidn 
del Instituto Mugucl UI|o. TucumSn. Acta Zon!6gica 
Lilloana 15:5-18. 
PiEROTH, R. AND C. Bellrose. 1986. Proximate and 
ultimate causation of egg size and the “third chick 
disadvantage" in the Western Gull. Auk 103:401-407. 
Pinheiro, J. c. AND D. M. Bates. 2000. Mixed effect 
models in S and S-plus. Springer-Verlag Inc., New 
York, USA. 
Plummer, M., N. Best, K. Cowles, and K. Vines. 2009. 
Coda: output analysis and diagnostics for MCMC. R 
package Version 0.13-5. http://CRAN.R-prqjcct.org' 
package=coda 
Pyle. P., L. B. Spear. W. J. Sydeman, and D. G. Aim ey 
1991. The effects of experience and age on the breeding 
performance of Western Gulls. Auk 108:25-33. 
R Development Core Team. 2009. R: a language and 
environment for statistical computing. R Foundation 
for Statistical Computing, Vienna. Austria, http:// 
www.R-project.org 
Reid, W. V. 1987. Constraints on clutch size in tlw Glaucous- 
winged Gull. Studies in Avian Biology 10:8-25. 
Royle, N. J. and K. C. Hamer. 1998. Hatching asynchrony 
and sibling size hierarchies in gulls: effects on parental 
investment decisions, brood reduction and reproduc¬ 
tive success. Avian Biology 29:266-272. 
Ryder, P. L. and J. P. Ryder. 1981. Reproductive 
performance of Ring-billed Gulls in relation to nest 
location. Condor 83:57-60. 
Slagsvold. T„ J, Sandvik, G. Roestad, O. Lorentsen. At® 
M. HUSBY. 1984. On the adaptive value of intraclutch 
egg size variation in birds. Auk 101:685-697. 
Stoleson, S. H. and S. R. Beissinger. 1995. Hatching 
asynchrony and the onset of incubation in birds, 
revisited: when is the critical period? Current Orni¬ 
thology 12:191-270. 
SYDBMAN, W. J. and S. D. Emslie. 1992. Effects of 
parental age on hatching asynchrony, egg size and 
third-chick disadvantage in Western Gulls. Auk 
109:242-248. 
Sydeman. W. J.. J. F. Penniman. T. M. Penniman. P. 
Pyle, and D. G. Ainley. 1991. Breeding performance 
in the Western Gull: effects of parental age, timing of 
breeding and year in relation to food availability. 
Journal of Animal Ecology 60:135-149. 
Williams. T. D. 1994. Intraspecific variation in egg sire 
and egg composition in birds: effects on offspring 
fitness. Biological Reviews 68:35-59. 
Winkler. D. w. and R. J. Walters. 1983. The 
determination of clutch size in precocial birds. Current 
Ornithology 1:33-68. 
Yorio, P. and G. Harris. 1992. Actualization dc la 
distribucidn reproductiva, estado poblacional y de 
conservacion de la Gaviota de Olrog (Larus atlanlicus). 
Homero 13:200-202. 
Yorio. P.. P. D. Boersma. and S. Swann. 1996. Breeding 
biology of the Dolphin Gull at Punta Tombo, 
Argentina. Condor 98:208-215. 
Yorio. P„ D. E. RAbano, and P, Friedrich. 2001. Habitat 
and nest site characteristics of Olrog's Gull Lams 
atlanlicus breeding at San Bias, Argentina. Bird 
Conservancy International 11:25-32. 
Yorio. P.. M, Bertellotti, and P. GarcIa Borborogll 
2005. Estado poblacional y de conservacidn de 
gaviotas que se rcproducen en el litoral maritime 
Argentino. Homero 20:53-74. 
Zl'ur, a. f.. e. N. Ieno. N. j. Walker, a. A. Saveliev. 
AND G. M. Smith, 2009. Mixed effects models and 
extensions in ecology with R. Springer Science r 
Business Media, New York, USA. 
