Site parameters’ variance – a missing dimension in the studies of nest-site selection?

• Autorzy: Skorka P. , Martyka R. , Wojcik J.D. , Lenda M.
• Języki publikacji: EN

Abstrakty

EN

In most studies of nest-site selection the data of habitat parameters are treated with analysis of variance. A basic assumption of this test is the homogeneity of variance. Here, we show that the nest-site selection process leads to lower variance of the selected parameters than in the case of random points which generally describe the available average characteristics of the environment. Thus, the variance should be accounted for in studies on nest-site selection and it should be treated not as a problem (as it is usually done), but as a source of additional important information on the selection process. Comparison only of mean values often does not lead to significant differences between nest site parameters and random points which may result from a small effect size (when animals select features similar to the general mean of available characteristics). Deeper insight into variance of the site parameters may elicit important results. We illustrate this issue with real data on nest site (islets and shores of water reservoirs) selection in the Common Gull Larus canus. Four (islet’s area, vegetation height on islets, vegetation cover on shore and distance to nearest shrub or tree on shore) from eight parameters were favored by the birds and, as predicted, their variance values were lower than of those not selected (vegetation cover on islets, distance of the islets to shoreline, vegetation height on shore and distance to water).

Słowa kluczowe

EN

breeding success; Common Gull; habitat; homogeneity; Larus canus; nest site selection; population dynamics; statistics; variance analysis

• Wydawca: -
• Czasopismo: Polish Journal of Ecology
• Rocznik: 2011
• Tom: 59
• Numer: 2
• Opis fizyczny: p.423-426,fig.,ref.

Twórcy

autor

Skorka P.

• Institute of Zoology, Poznan University of Life Sciences, Wojska Polskiego 71 C, 60–625 Poznan, Poland

autor

Martyka R.

autor

Wojcik J.D.

autor

Lenda M.

Bibliografia

• Atiénzar F., Barba E., Holleman L.J.M., Belda E.J. 2009 – Nesting habitat requirements and nestling diet in the Mediterranean populations of Crested Tits Lophophanes cristatus – Acta Ornithol. 44: 101–108.
• Belthoff J.R., Ritchinson G. 1990 – Nestsite selection by eastern screech-owls in central Kentucky – Condor, 92: 982–990.
• Cody M.L. 1985 – Habitat selection in birds – Academic Press, New York, 558 pp.
• Iraeta P., Diaz J.A., Bauwens D. 2007 – Nest-site selection by Psammodromus algirus in a laboratory thermal gradient – J. Herpet. 41: 360–364.
• Jones J. 2001 – Habitat selection studies in avian ecology: a critical review – Auk, 118: 557–562.
• Kikvidze Z., Moya-Larano J. 2008 – Unexpected failures of recommended tests in basic statistical analyses of ecological data – Web Ecol. 8: 67–73.
• LaHaye W.S., Gutierrez R.J., Call D.R. 1997 – Nest-site selection and reproductive success of California Spotted Owls – Wilson Bull. 109: 42–51.
• McCallum D.A., Gehlbach F.R. 1988 – Nest-site preferences of Flammulated Owls in western New Mexico – Condor, 90: 653–661.
• Mirski P. 2009 – Selection of nesting and foraging habitat by the Lesser Spotted Eagle Aquila pomarina (Brehm) – Pol. J. Ecol. 57: 581–587.
• Morán-López R., Sánchez Guzmán J.M., Costillo-Borrego E., Villegas Sánchez A. 2006 – Nest-site selection of endangered cinereous vulture (Aegypius monachus) populations affected by anthropogenic disturbance: present and future conservation implications – Anim. Conserv. 9: 29–37.
• Olabarria C., Underwood A., Chapman M. 2002 – Appropriate experimental design to evaluate preferences for microhabitat: an example of preferences by species of microgastropods – Oecologia, 132: 159–166.
• Partridge L. 1978 – Habitat selection (In: Behavioural ecology: an evolutionary approach, Eds: J.R. Krebs and N. Davies) – Sinauer Assoc., Sunderland, Massachusetts, pp. 351–376.
• Rice W.R., Gaines S.D. 1989 – One-way analysis of variances with unequal variances – PNAS, 86: 8183–8184.
• Skórka P., Martyka R., Wójcik J. D., Babiarz T., Skórka J. 2006 – Habitat and nest site selection in the Common Gull Larus canus in southern Poland - significance of man-made habitats for an endangered species – Acta Ornithol. 41: 137–144.
• Zar J. 1999 – Biostatistical analysis – Prentice Hall, 662 pp.