LE3 .A278 2008

2008

Shutler, Dave

Acadia University

Bachelor of Science

Honours

Biology

Biology

The ability to predict hatch date can be important to studies on chick growth. Three common ways of estimating embryo development in Leach’s storm-petrel eggs were examined including candling, egg flotation, and weighing. Candling involves using illumination to visualize features of the developing embryo within the egg shell. Egg flotation and mass rely on eggs losing mass as embryo metabolism converts egg contents to gases that escape through the egg’s shell. I found no significant correlation between estimated hatch dates for any of these methods, possibly due to extreme variability in incubation periods for these birds. In a separate study, the rationale underlying mate choice in Leach’s stormpetrels was considered. Mate choice may be based on how genetically compatible a partner is, but mechanisms by which organisms assess a prospective partner’s genes have not been well-studied. Mating can be assortative, disassortative, or random. Assortative mating suggests that partners choose each other based on similarity, such as in morphology. However, there is also selection to avoid breeding with close relatives, which favours disassortative mating. The ideal mating strategy may lie between these extremes, and be indistinguishable from random mating. Fifty-two pairs of birds were tested for similarity in morphological traits, including wing, primary, tail, culmen, tarsus, headbill length, head width, and mass. Mating was disassortative with respect to culmen lengths, but appeared to be random with respect to the other traits examined.

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https://scholar.acadiau.ca/islandora/object/theses:525