Fauna
Species

Neptune's Necklace

Hormosira banksii

Also known as Neptune's Pearls, Bubbleweed, Sea Grapes

Neptune's necklace forms distinctive chains of water-filled, hollow beads along temperate rocky shorelines of Australia and New Zealand. Each bead acts as a buoyancy float when submerged and retains moisture to resist desiccation when exposed to air and sunlight at low tide. These sprawling, rubbery mats serve as crucial ecosystem engineers, shielding intertidal invertebrates and juvenile fish from heat stress and predation.

MarineIntertidalAlgae
Neptune's Necklace reference1 / 7
(c) Jon Sullivan, some rights reserved (CC BY) · cc-by
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Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preySunlight, Dissolved carbon dioxide, Marine dissolved nutrients
Predators
  • Herbivorous sea snails
  • Sea urchins
  • Limpets
ThreatsHuman trampling, coastal runoff, and ocean warming
HabitatsRocky intertidal reefs, shore platforms, and rock pools
Life span3–5 years
Classification
  1. OrderFucales
  2. FamilyHormosiraceae
  3. GenusHormosira
  4. SpeciesHormosira banksii
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance; watch for slippery surfaces on rocky platforms.
Responsible observation
  • Tide Timing: Explore rock platforms during falling or low tides when the beaded fronds are fully exposed.
  • Footwear Etiquette: Avoid walking directly across dense beds, as repeated trampling ruptures the beads and detaches fronds.
  • Microhabitat Search: Gently lift fronds in wet gullies to discover small crabs and sea snails hiding in the damp understory.
Related species
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Found in Collections

Ecosystem chain

Wetland Territory

Neptune's Necklace is found in this collection. Identify it in Fauna to fill this slot and continue your progress.

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