Neptunes Necklace

Hormosira banksii

''Hormosira banksii'' is a species of seaweed found in Australia and New Zealand. It is commonly found in rock pools at mid-tide levels and is characterised by strings of olive-brown hollow beads. The beads have a slimy layer which conserves moisture. They also contain gas, allowing them to rise to the surface of the water, obtaining more sunlight and moving with the flow of the current. Each bead is filled with water that prevents desiccation between tides.
Neptune’s Necklace - Hormosira banksii           Australia,Eamw aquatic plants,Geotagged,Hormosira banksii,Neptunes Necklace,Summer

Habitat

This seaweed is mostly found in the littoral zone or in rock pools, where they receive plenty of light and enough sea water to avoid desiccation. One of their behavioural adaptations is living in groups, preventing moisture loss and drying out.
Neptunes necklace (Hormosira banksii) Greenish brown-algae made of strings of hollow, water-filled, round beads on a short stalk. Each bead has a smooth surface except for an even array of tiny tubercules (containing reproductive cells) and is about 12-15mm diameter. The strings might be up to 200mm long and many strings many grow from a single base.
These were growing in a small nature reserve.
Also called sea grapes... they sure are fun to tread on when found washed up on the beach.  Australia,Geotagged,Hormosira banksii,Hormosira banksii/Neptunes Necklace,Spring

Reproduction

The form of this seaweed reproduces asexually from broken fragments. The attached form of the seaweed reproduces sexually. Their sex organs are found on the surface of the beads. At high tides, the plant squeezes out its clusters of eggs or sperm in sticky masses. All plants release at the same time, maximising its fertilisation.
Neptunes Necklace - Hormosira banksii At low tide fast areas full of Hormosira banksii seaweed are exposed . Australia,Eamw aquatic plants,Geotagged,Hormosira banksii,Neptunes Necklace,Summer

Predators

Neptune's necklace is a food source for sea urchins, crustaceans and some fish. Young crustaceans and molluscs often live in the moist areas of the plant, for protection from predators and to retain moisture under low tide conditions.

References:

Some text fragments are auto parsed from Wikipedia.

Taxonomy
KingdomChromista
DivisionOchrophyta
ClassPhaeophyceae
OrderFucales
FamilyHormosiraceae
GenusHormosira
SpeciesH. banksii
Photographed in
Australia