PORT PHILLIP BAY

Soft substrates

Soft sediments are common in Port Phillip and elsewhere along the Victorian coast. Desert-like, sand plains appear barren because most of the life there is microscopic. In fact, thousands of individuals can occur in a square meter of sand. Some larger animals survive here by burrowing into the substrate to hide during the day and emerging at night to feed. Finer sediments and mud occur where minimal wave action allows the accumulation of small, organic particles. As a result, these areas are often in estuaries, sheltered bays and inlets. Typical representatives of muddy areas shelter under overlying rocks or in widespread seagrasses covering the mud, or make semi-permanent burrows in the sediment.

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Soft substrates habitat video

For large areas of the bay, the seafloor are sand plains. Now these might look like baron deserts but they’re actually teeming with life.

Now, lots of these animals hide in the sand, they bury, or they’re really good at camouflage. The few you do see out and about, usually have spines or poisons as a way of defending themselves. But it’s at night that these areas really come alive. All sorts of animals come crawling out of the sand to run around and hunt under the cover of darkness.