Search

Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory, primarily herbivorous mega-consumers that may migrate over hundreds to thousands of kilometers. Our dataset, the largest ever compiled for sea turtles, has 9690 growth increments from 30 sites from Bermuda to Uruguay from 1973 to 2015. Using generalized additive mixed models, we evaluated covariates that could affect growth rates; body size, diet, and year have significant effects on growth. Growth increases in early years until 1999, then declines by 26% to 2015. The temporal (year) effect is of particular interest because two carnivorous species of sea turtles-hawksbills, Eretmochelys imbricata, and loggerheads, Caretta caretta-exhibited similar significant declines in growth rates starting in 1997 in the West Atlantic, based on previous studies. These synchronous declines in productivity among three sea turtle species across a trophic spectrum provide strong evidence that an ecological regime shift (ERS) in the Atlantic is driving growth dynamics. The ERS resulted from a synergy of the 1997/1998 El Niño Southern Oscillation (ENSO)-the strongest on record-combined with an unprecedented warming rate over the last two to three decades. Further support is provided by the strong correlations between annualized mean growth rates of green turtles and both sea surface temperatures (SST) in the West Atlantic for years of declining growth rates (r = -.94) and the Multivariate ENSO Index (MEI) for all years (r = .74). Granger-causality analysis also supports the latter finding. We discuss multiple stressors that could reinforce and prolong the effect of the ERS. This study demonstrates the importance of region-wide collaborations.

In response to a call from the US National Research Council for research programs to combine their data to improve sea turtle population assessments, we analyzed somatic growth data for Northwest Atlantic (NWA) loggerhead sea turtles (Caretta caretta) from 10 research programs. We assessed growth dynamics over wide ranges of geography (9–33°N latitude), time (1978–2012), and body size (35.4–103.3 cm carapace length). Generalized additive models revealed significant spatial and temporal variation in growth rates and a significant decline in growth rates with increasing body size. Growth was more rapid in waters south of the USA (

DAVID R. BREININGER*MARY JO BARKASZIREBECCA B. SMITHDONNA M. ODDYJANE A. PROVANCHADynamac InternationalNASA Biomedical Operations OfficeDyn-2, John F. Kennedy Space Center, Florida 32899, USAABSTRACT / We identified and ranked 108 resident and mi-gratory wildlife taxa on John F. Kennedy Space Center (KSC)that were vulnerable to local, regional, or global extinction.We ranked taxa based on their vulnerability to extinction,their potential role for maintaining faunal integrity, and therelevance of KSC for maintaining their populations in theUnited States and Florida. Several taxa, not listed by agen-cies, were vulnerable to regional or global extinction. Manytaxa not vulnerable to global extinction were vulnerable tolocal and regional extinction. Top predators were vulnerableto extinction because of small population size, isolation fromother populations, and road mortality. Many taxa were de-pendent on habitat conditions at different geographic loca-tions so that conservation required greater collaborationamong land owners, managers, and researchers at local,regional, and global scales.