Functional roles of abyssal benthos in sustaining polymetallic nodule fields.

Benthic faunal behavior may be a key mechanism in maintaining polymetallic nodules on the abyssal seabed, with sediment removal and uplift occurring over yearly to decadal timescales.

• Why it matters: Understanding how nodules remain on the surface is crucial because they support high biodiversity in abyssal plain ecosystems, yet their long-term maintenance mechanisms are largely unknown.
• What they did: Seabed time-lapse photography was used to observe species like holothurians and gastropods removing sediment and causing nodule uplift, with estimates indicating that these behaviors operate over decades.
• The result: Benthic activity potentially counteracts nodule burial, highlighting its role as a habitat engineer that influences ecosystem resilience and offers new avenues for monitoring abyssal ecosystem functioning.