Mesoscale ocean eddies determine dispersal and connectivity of corals at the RMS Titanic wreck site

Introduction

• The RMS Titanic wreck, located 3800 meters deep, serves as a hard substratum for marine organisms, including the octocoral Chrysogorgia agassizii.
• Understanding the Titanic’s role in connecting ecosystems is crucial due to its rapid deterioration and the vulnerability of deep-sea coral populations.

Methods and Materials

• The study used high-resolution numerical ocean models and Lagrangian experiments with over one million virtual particles to simulate larval dispersal from the Titanic.
• Various scenarios for larval behaviour were considered, given the uncertainties around the biology of Chrysogorgia species.

Findings

1. Dispersal Pathways:
   • Larvae from the Titanic follow two main pathways: westward along the 3500-meter isobath and southward between the 3500 and 4000-meter isobaths.
   • Mesoscale ocean eddies significantly influence these pathways, outweighing the effects of mean flow and larval swimming behaviour.
2. Role of Eddies:
   • Eddies can cause a significant speed-up or reversal of the deep circulation, affecting larval dispersal.
   • The position of eddies largely controls the direction and distance of larval dispersal.
3. Connectivity:
   1. The Titanic could act as a stepping stone, connecting the upper continental slope off Newfoundland to deeper waters.
   2. Larvae from the Titanic can spread into deep Canadian waters and areas beyond national jurisdiction.

Discussion

• The study highlights the importance of mesoscale eddies in determining larval dispersal patterns.
• The Titanic’s role in marine connectivity is influenced by stochastic processes on subseasonal timescales.
• Further research on larval biology and behaviour is needed to refine these findings.

Conclusion

• The Titanic plays a significant role in ecosystem connectivity, potentially acting as a stepping stone for coral dispersal.
• Understanding the interaction between ocean dynamics and larval behavior is crucial for conservation efforts.