Population characteristics, age structure, and growth dynamics of neritic juvenile green turtles in the northeastern Gulf of Mexico

Marine Ecology Progress Series

Brian Stacy¹  Joanne Braun-McNeill¹  Eric T. Anderson¹  Craig A. Harms¹  Margaret M. Lamont¹  Larisa Avens¹  Matthew H. Godfrey¹  Rhonda Bailey¹  Wendy M. Cluse¹  Lisa R. Goshe¹  April Goodman Hall¹ 

关键词: Chelonia mydas;    St. Joseph Bay;    Florida;    Sea turtle;    Cold stun;    Skeletochronology;    Sex ratio;   

DOI  :  10.3354/meps09720

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: Characterization of a population of green turtles inhabiting the northeastern Gulf of Mexico was made possible by the mortality of a subset of >4500 sea turtles that stranded during a mass cold stunning event in Florida, USA, during January 2010. In total, 434 dead, stranded green turtles Chelonia mydas were evaluated through necropsy and skeletochronological analysis to characterize morphology, sex, body condition, disease status, age structure, and growth patterns. Standard straightline carapace lengths ranged from 18.1 to 78.5 cm (mean ± SD = 36.3 ± 10.4 cm) and did not significantly differ from those of stranded green turtles that survived this event. Prevalence of fibropapilloma (FP) was low, at 6%, and sex ratio was significantly biased toward females (2.45F:1M). Age estimates ranged from 2 to 22 yr (mean ± SD = 9 ± 4 yr) and female age distribution was significantly greater than that of males. Mean stage durations, as calculated through summation of size class-specific growth rates and fitting smoothing spline models to length-at-age data, were similar and ranged from 17 to 20 yr. Generalized additive models and generalized additive mixed models were used to assess the potential influence of discrete and continuous covariates on growth rates. Somatic growth was significantly influenced by size, age, and calendar year; however, no effect of sex, FP status, or body condition was found. Increased understanding of population parameters will improve population models for the species and can also serve as a reference for assessing potential effects of the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.

【 授权许可】

Unknown