Variation in Egg Components A Study of Maternal Investment and Resource Partitioning in the Nesting Loggerhead Sea Turtle


Meeting Abstract

90.1  Friday, Jan. 6  Variation in Egg Components: A Study of Maternal Investment and Resource Partitioning in the Nesting Loggerhead Sea Turtle. PATEL, K*; WILLIAMS, K; FRICK, M; ROSTAL, D; GSU; Caretta Project; Caretta Project; GSU patelkv@hendrix.edu

Understanding maternal contributions and strategies in reproduction can reflect how resources are allocated in response to resource availability and physiological constraints of the mother. Sea turtles have the highest egg yields of any oviparous non-avian reptiles, laying from 50-130 eggs multiple times in a nesting season. Each clutch represents 1-10 % of a female’s total body mass. Loggerhead sea turtles have high seasonal fecundity and display little variation in egg size, and instead maximize clutch size. This study was conducted on Wassaw Island National Wildlife Refuge during the 2008-2010 nesting seasons. Comparisons of wet and dry egg mass were made to assess the direct maternal effects. Wet egg mass and albumen mass (0.01 < p < 0.025) significantly decreased across the nesting season however, wet yolk did not. Dry component analysis showed that dry yolk (P = 0.1732) and albumen ( 0.1 < p < 0.5) did not differ across the nesting season. Results of ash free dry mass analysis showed that there is no difference in the ratio of organic vs. inorganic material in albumen or yolk throughout the nesting season(H = 0.3556, df = 2, P = 0.8371 and H= 1.8667, df = 2., P = 0.3932, respectively). Bomb calorimetry data showed that there was no variation between periods of the nesting season. In addition, results show that dry yolk mass has a stronger correlation to caloric content than wet yolk mass and eggs with bigger yolks had overall more caloric content. This study also shows that females are providing the same amount of albumen and yolk to all clutches but differing amounts of water. Due to the rainfall pattern, the decrease in water allocated to the eggs is compensated by the rise in rainfall during the incubation period. This study supports the conclusion that in C. caretta, hatchling size, not egg size, is being selected for.

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