Growth of the brown noddy (Anous stolidus) in the Dry Tortugas

Brown Noddy nestlings in the Dry Tortugas exhibit a growth rate that is slower than would be predicted, based on adult body size and mode of development. This pattern of prolonged growth is typical of tropical pelagic seabirds. An intraspecific comparison of growth rates among several populations of Brown Noddies indicates that growth of body mass of the Tortugas Noddies is significantly faster, the development period shorter, and the asymptotic size smaller than in Pacific populations. However, there were no differences among the populations in the rates of wing or culmen growth. The Bush Key nestlings appear to receive a higher quality diet that contains proportionally more fish, while the Pacific nestlings receive substantial amounts of squid. The Pacific nestlings also seem to be subjected to a thermally more stressful microclimate, which may necessitate the allocation of proportionally more of their total energy to thermoregulation and less to growth.