More than a century after it sank, the RMS Titanic continues to evolve — not only structurally, but biologically. A recent survey of the wreck and a nearby deep-sea ridge has revealed the marine life now thriving across its steel remains at a depth of about 3,800 metres in the North Atlantic.
The study is based on video footage captured during a 2022 expedition and compares species living on the wreck with those found on a natural rocky ridge roughly 40 kilometres away. Scientists examined more than 1,000 still images extracted from submersible recordings. Their findings indicate that the Titanic has effectively become an artificial reef, supporting corals, sponges and a range of mobile invertebrates in an area once largely covered by soft sediment.
Corals and invertebrates colonise the wreck
Footage from the site shows brittle stars, squat lobsters, sea anemones and multiple sponge species attached to railings and fractured metal sections. Cold-water corals, including species from the genera Chrysogorgia and Lepidisis, have established themselves on elevated structures such as the bow and deck fittings.
These organisms rely on the ship’s steel framework as a rare hard surface in an otherwise muddy seabed. Prior to the Titanic’s arrival in 1912, the surrounding environment consisted mostly of soft sediment. The sudden presence of complex metal structures created new habitat for suspension feeders to anchor, feed and grow.
Although researchers recorded lower overall biodiversity at the wreck compared with the nearby ridge, the Titanic now hosts a distinct biological community shaped by its architecture and gradual decay.
Natural ridge shows greater biodiversity
The comparison site, part of a feature known as Seamount U, lies at approximately 2,900 metres depth and is composed of volcanic rock formations and pillow lava. Images from the ridge revealed a higher number of species and greater diversity than at the wreck.
Thick clusters of corals, sponges, crinoids and fish were observed along rocky outcrops. Scientists suggest the ridge provides a more stable habitat, possibly aided by stronger ocean currents that deliver a steady supply of food particles.
Statistical analysis confirmed clear differences between the biological communities at the two sites. Factors such as substrate type, hydrodynamic conditions and food availability are likely driving these variations.
Coral growth and structural change over decades
Researchers also compared recent footage with archival material dating back to 1986. The comparison shows that some coral colonies have grown significantly, with estimated expansion rates reaching up to 10 millimetres per year. At the same time, rust formations known as “rusticles” have lengthened, in some cases by about 14 millimetres annually.
These observations highlight an ongoing process of ecological succession. While the ship’s structure continues to weaken and deteriorate, it simultaneously provides habitat for marine life — a balance between decay and biological growth.
A deep-sea artificial reef
Shipwrecks at such depths are rarely studied in comparable detail. The findings suggest that artificial structures like the Titanic can serve as ecological stepping stones, allowing species to disperse across vast stretches of the deep ocean floor. Larvae may settle on wrecks before spreading to other hard surfaces in the region.
However, scientists note that climate change could alter deep-sea temperatures, chemistry and oxygen levels in the North Atlantic, potentially affecting both coral growth and the rate of steel corrosion.
For now, the Titanic remains one of the few deep-sea sites revisited frequently enough to allow long-term comparison. In the darkness nearly four kilometres below the surface, its steel framework preserves both history and a slowly evolving marine ecosystem.
