Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic

• DOI: 10.1111/gcb.13712
• Publication Date: 2017-04-05T17:27:37Z
• Authors: Karen A. Bjorndal; Alan B. Bolten; Milani Chaloupka; Vincent S. Saba; Cláudio Bellini; Maria A. G. Marco...; Armando J. B. Santos; Luis Felipe Wurdi...; Anne B. Meylan; Peter A. Meylan; Jennifer Gray; Robert Hardy; Beth Brost; Michael Bresette; Jonathan C. Gorham; Stephen Connett; Barbara Van Scive...; Mike Dawson; Deborah Hayes; Carlos E. Diez; Robert P. van Dam; Sue Willis; Mabel Nava; Kristen M. Hart; Michael S. Cherkiss; Andrew G. Crowder; Clayton Pollock; Zandy Hillis‐Starr; Fernando A. Muñoz...; Roberto Herrera‐P...; Vanessa Labrada‐M...; Armando Lorences; Ana Negrete‐Philippe; Margaret M. Lamont; Allen M. Foley; Rhonda Bailey; Raymond R. Carthy; Russell Scarpino; Erin McMichael; Jane A. Provancha; Annabelle Brooks; Adriana Jardim; Milagros López‐Me...; Daniel González‐P...; Andrés Estrades; Alejandro Fallabrino; Gustavo Martínez‐...; Gabriela M. Vélez...; Ralf H. Boulon; Jaime A. Collazo; Robert Wershoven; Vicente Guzmán He...; Thomas B. Stringell; Amdeep Sanghera; Peter B. Richardson; Annette C. Broderick; Quinton Phillips; Marta Calosso; John A. B. Claydon; Tasha L. Metz; Amanda L. Gordon; Andre M. Landry; Donna J. Shaver; Janice Blumenthal; Lucy Collyer; Brendan J. Godley; Andrew McGowan; Matthew J. Witt; Cathi L. Campbell; Cynthia J. Lagueux; Thomas L. Bethel; Lory Kenyon
• Keywords: Ectotherm

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