Female migrations from foraging grounds to nesting beaches are ecologically significant journeys. When females lay their eggs on sandy shorelines, they introduce nutrients and energy from distant and dispersed foraging grounds into relatively small and nutrient-poor beaches. One of the longest and most impressive examples of this transfer of nutrients is by leatherbacks, which feed on jellyfish near the Arctic circle and nest on tropical beaches.
Sea turtle eggs have four possible fates, each with its own energy path:
- The eggs hatch and most of the nutrients return to the sea as hatchlings, leaving some nutrients on the beach in the form of eggshells and embryonic fluid;
- The eggs fail to hatch, allowing nutrients to enter the detrital food chain;
- The eggs are consumed by predators; or
- The eggs are penetrated by roots, enabling plants to absorb the nutrients. In addition, nesting and the emergence of hatchlings bring egg matter and nest organisms to the surface. These processes help disperse nutrients to small organisms in beach sand. Consequently, the presence of turtle eggs drives community dynamics on nesting beaches.