5 mistaken marine identities you might find along South Australia’s beaches

5 mistaken marine identities you might find along South Australia’s beaches



Before enjoy­ing your next beach walk, smarten up your sea­side knowl­edge with these five com­mon­ly mis­tak­en finds.


There are lots of inter­est­ing crea­tures and plants that wash ashore on South Australia’s beach­es. But some are reg­u­lar­ly misiden­ti­fied – with the mis­in­for­ma­tion often flow­ing down from gen­er­a­tion to generation.

So here are the facts – to set the record straight – about the five com­mon­ly mis­tak­en finds along SA’s coastline.

1. Jel­ly sack

5 mistaken marine identities you might find along South Australia’s beaches

5 mistaken marine identities you might find along South Australia’s beaches

Jel­ly sacks are not jel­ly­fish. Instead they are an egg mass laid by moon snails. The eggs are encased in the clear, moon-shaped, jel­ly-like sub­stance. So when you are squish­ing them between your toes remem­ber you are actu­al­ly squish­ing tiny moon snails. 

2. Sponge

5 mistaken marine identities you might find along South Australia’s beaches

This lit­tle guy is often mis­tak­en for a plant, but is actu­al­ly an animal.

Sponges are sim­ple animals.

They have a skele­ton made up of a fibrous mate­r­i­al called Spon­gin. Sponges pump water through pores to extract food and expel waste water through larg­er holes called Oscules.

Sponges can be washed ashore shaped like wine glass­es, fin­gers, balls or flat spiky mats.

3. Sea­grass wrack

5 mistaken marine identities you might find along South Australia’s beaches

Sea­grass wrack reg­u­lar­ly wash­es along our shores. It is often mis­tak­en for algae which is known as sea­weed, but is actu­al­ly a plant with roots and leaves.

Read up on sea­grass wrack ver­sus sea­weed.

4. Sea tulip

Sea tulip
Sea tulip
Sea tulip underwater (image courtesy of S.Reynolds)
Sea tulip under­wa­ter (image cour­tesy of S.Reynolds)

Anoth­er spec­i­men that wash­es up along our beach­es and is mis­tak­en for sea­weed is the sea tulip. Sea tulips are actu­al­ly from the ani­mal king­dom. They are fil­ter feed­ers, mean­ing they pump water in and out of their siphons (tube-like struc­tures) and extract the plankton.

5. Velel­la/­By-the-wind sailor

5 mistaken marine identities you might find along South Australia’s beaches

Velel­las are often mis­tak­en for the ven­omous stinger jel­ly­fish known as the blue­bot­tle. Luck­i­ly blue­bot­tles are not gen­er­al­ly found in SA. Although they’re not ven­omous, it’s best not to touch them.

Each velel­la has a disc-like float with a trans­par­ent sail which the ani­mal uses to drift around the ocean sur­face. Some­times you will find large num­bers of them washed ashore.

Top tip: Remem­ber to leave plants and ani­mals where you find them. In many areas such as rocky coast­lines and marine park sanc­tu­ary zones, it is ille­gal to take specimens.

Check out theBeach Explorer’s Guide to Plants and Ani­mals in South Aus­traliato learn more about the things you can find along our beaches. 

This sto­ry was orig­i­nal­ly post­ed in May 2017.


This con­tent was pro­duced in part­ner­ship with  Good Living