Long-term changes in body size of green turtles nesting on Trindade Island, Brazil: Signs of recovery?

Mar Environ Res. 2023 Apr:186:105930. doi: 10.1016/j.marenvres.2023.105930. Epub 2023 Feb 26.

Abstract

Trindade Island is an important wildlife refuge in the South Atlantic Ocean and hosts the largest nesting population of green turtles (Chelonia mydas) in Brazil, about which temporal ecological dynamics are still not well understood. The present study examines 23 years of nesting for green turtles at this remote island to evaluate annual mean nesting size (MNS) changes and post-maturity somatic growth rates. Our results show a significant decrease in annual MNS over the study; Whereas MNS during the first three consecutively monitored years (1993-1995) was 115.1 ± 5.4 cm, during the last three years (2014-2016) it was 111.2 ± 6.3 cm. There was no significant change in post-maturity somatic growth rate over the course of the study; the mean annual growth rate was 0.25 ± 0.62 cm/year. These findings suggest an increase in the relative proportion of smaller, presumptive neophyte nesters appearing in Trindade during the study period.

Keywords: Body size; Conservation; Mean nesting size; Monitoring; Population ecology; Southwestern Atlantic Ocean; Time-series.

MeSH terms

  • Animals
  • Animals, Wild
  • Atlantic Ocean
  • Body Size
  • Brazil
  • Nesting Behavior
  • Turtles*