North American Crane Working Group

 

Date of this Version

2005

Document Type

Article

Citation

Aguilera, X.G., V.B. Alvarez, and F. Chavez-Ramirez. Nesting ecology and productivity of the Cuban sandhill crane on the isle of Youth, Cuba. In Chavez-Ramirez, F, ed. 2005. Proceedings of the Ninth North American Crane Workshop, Jan 17-20, 2003. Sacramento, California: North American Crane Working Group. Pp. 225-236.

Comments

Reproduced by permission of the NACWG.

Abstract

We studied nesting ecology and productivity of the Cuban sandhill crane in the Isle of Youth Cuba between 1997-2003. The nesting season extended from late march through June, but due to variable weather conditions could begin in February or extend through July. Overall, 71.1% of nests located produced eggs, while 84.1% of nests with eggs hatched at least one chick. Mean clutch size was 1.72 eggs. There were significant differences in hatching rates (G = 19.05, P < 0.01) and successful nests between years (G = 9.59, P < 0.10). Chicks/successful nest and rainfall during the breeding period (r = 0.6) were positively correlated. Percent successful nests was negatively correlated with total rainfall during the breeding season (r = -0.50). Causes of egg or nest failure included nest abandonment, predation, flooding, and infertility. In regards to breeding biology we recorded feather painting prior to nesting activity, false nests, and a re-nesting attempt after nest destruction. All nests were built on dry land. Cranes selected four of 11 habitat types present in the study area for nesting: open savannah (SNA) (24.2%), semi-closed natural savannah (SSC) (50.67%), open pine woodland (SPPA) (17.7%), and secondary savannah (SS) (7.7%). Palm density, seedlings, and forbs were lower at nest sites compared to random points, while ground cover of sand and litter was greater at nest sites. There were no significant differences in frequency of plant species among nest sites and random points (G = 3.78, P > 0.05). Tree species richness was less at nest sites, likely due to dominance of Tabebuia lepiodphylla and Byrsonima crassifolia species. Significant differences (G = 15.8, P < 0.01) were found in frequency of palm species, with greater density of Colpothrinax wrightii and Coccothrinax miraguama at nests sites. Shrub density was significantly higher (G = 194.68, P < 0.001) at nest sites being dominated by T. lepidophylla. There were no significant differences among nest sites and random points in forb variables (G = 6.67, P > 0.05) with similar frequency at both sites.