Heavy Metal Concentrations in Sea Turtles and Their Prey in the Northwest Atlantic

• Main Author: Yi Wynn Chan
• Format: Thesis
• Language: unknown
• Published: 2024
• Subjects: Marine and estuarine ecology (incl. marine ichthyology); Toxicology (incl. clinical toxicology); Heavy metals > Environmental aspects > Analysis; Chelonia mydas (green turtle); Caretta caretta; Lepidochelys kempii; Atlantic Ocean coast; Northwest Atlantic
• Online Access: https://doi.org/10.25394/pgs.25655430.v1

The Northwest Atlantic Ocean, which surrounds the US eastern coastline, is an area rich in marine life. The US eastern coastline is also highly urbanized, resulting in a lot of pollutants (like heavy metals) entering the marine environment. This is of concern for long-lived marine species like sea turtles. Since sea turtles are long-lived and highly migratory, their tissues can often incorporate these pollutants through environmental and dietary exposure. I collected tissue samples from 5 different sea turtle populations in the Northwest Atlantic and analyzed them for concentrations of silver (Ag), aluminum (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se) and zinc (Zn) using an Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The first chapter looks at skin (reflects exposure ~1 year ago) and scute (reflects exposure from 4-6 years ago) samples collected during necropsies of juvenile green ( Chelonia mydas ) (n=8), Kemp’s ridley ( Lepidochelys kempii ) (n=30) and loggerhead ( Caretta caretta ) (n=17) turtles that were found cold-stunned in Cape Cod Bay, Massachusetts. In scute samples, the heavy metal with the highest concentration for green turtles was iron, zinc for loggerhead turtles, and arsenic for Kemp’s ridley turtles. In skin samples, the heavy metal with the highest concentration for green turtles was iron, arsenic for loggerhead turtles, and aluminum for Kemp’s ridley turtles. Overall, I found scute samples to have higher heavy metal concentrations than skin samples. The second chapter looks at scute samples collected from loggerhead turtles of different life stages. These samples were collected during necropsies of cold-stunned loggerhead turtles from Cape Cod Bay, Massachusetts (CCB; n=17), as well as from live loggerhead turtles in the Mid-Atlantic Bight (MAB; n=37) and off the coast of North Carolina (NC; n=9). We also collected commonly known loggerhead turtle prey items including whelk ( Buccinum undatum ) (n=12), ...