Intertidal rocky shores

Introduction

Blue sky and rock pools all over the ground. Sea in the distance. Students walk on top of the rocks looking down at the ecosystems. — Students exploring an intertidal rocky shore.

Intertidal rocky shores¹ are located at the base of rocky headlands. They contain a huge variety of plants and animals that are able to survive in a harsh environment.

Animals

Some of the main animals species include limpets², barnacles³, perriwinkles⁴, cunjevoi⁵ and sea stars⁶.

Plants

Interesting plants include coralline algae⁷, neptunes necklace⁸, kelp⁹, strap weed¹⁰ and sea lettuce¹¹.

Location

three primary school students examine a rock pool. Students are holding an indeifitcation sheet showing images of common plants and animals. — Students investigating coastal biodiversity at Bateau Bay.

Intertidal rocky shores are located all around Australia’s vast coastline in a variety of different forms.

Types of rocky shores

Some are flat and horizontal (Norah Head¹², Bateau Bay¹³), some consist of boulders (Copacabana¹⁴) and others are highly contorted and fractured with steeply dipping strata (Seal Rocks¹⁵).

Google Earth

An example of an Intertidal ecosystem lies in the area around Copacabana Beach on Google Earth¹⁶. To move out of street view level and look at the wider area click the yellow person icon in the bottom right hand corner.

Significance

A white sea slug that has a layer of frill around its' body with a black highlight and two antenna with fringy fronds. It is weird and pretty. — Nudibranchs can be found on intertidal rocky shores and are noted for their often extraordinary colours and striking form.

Intertidal rocky shores contain interesting areas for exploration and education. They provide habitat for a huge variety of plants and animals that are uniquely adapted to a harsh physical environment that includes strong wave action, fluctuating weather conditions and changes in the tide.

Microhabitats

Each tiny crack or crevice can contain its own micro habitat and the full extent of the relationships that exist between all these organisms is still being explored.

Conservation

A sea snail with a spiral shell shape has a blue frilly body that spreads out around the shell. — The bubble snail takes advantage of warm and shallow waters in coastal rock pools.

Intertidal rocky shores have suffered a huge loss in biodiversity. Many animals such as crabs, sea squirts and sea urchins are taken by people for food and bait. Popular areas also suffer from habitat destruction through trampling of animals, overturning of boulders and pollution.

Aquatic reserves

In an attempt to solve pollution problems¹⁷ and halt the loss of biodiversity, aquatic reserves¹⁸ have been declared in the worst effected regions (mostly Sydney). Collection of seashore animals in these areas is strictly prohibited. In non-protected areas bag limits are enforced so that numbers of seashore animals that can be collected is restricted. Penalties apply if bag limits are broken.

Protective measures

Interpretative signs highlighting the importance of rock platforms and bag limits have also been erected to encourage people to behave responsibly. In Bouddi National Park¹⁹ (Central Coast) all marine life are protected by a Marine Extension.

Environmental education centres

A student holds a group of three barnacle shells up to the camera. There are no animals living inside the shells anymore. — Barnacles grow on hard surfaces including the rocks of tidal pools.

Rumbalara Environmental Education Centre²⁰ conducts Stage 2 programs at Copacabana Beach and Bateau Bay Beach (Wyrrabalong National Park²¹). These programs focus on discovering rock platform ecology and conserving coastal environments.

More locations

Other Environmental Education Centres that provide access to intertidal rocky shores include:

Illawarra²² (South Coast)
Cascade²³ (North Coast)
Georges River²⁴ (South Western Sydney)
Dorroughby²⁵
Royal National Park²⁶.

Further information

Knobbly seaweed lying on some sand right next to a rock pool. There are a number of molluscs on or near the seaweed. They are probably eating it. — Intertidal rock platforms host a variety of species.

Weblinks

Visit the Rumbalara Environmental Education Centre's website²⁰.
Life on Australian seashores²⁷ is an excellent website providing information on ecology, plants and animals of rocky shores.
NSW Office of Environment & Heritage – Types of protected areas²⁸
NSW Office of Environment & Heritage – Sydney Ocean Beaches²⁹
NSW Office of Environment & Heritage – Aboriginal use of the coast³⁰
QLD Department of Environment and Heritage Protection – Rocky shore³¹
Marine Discovery Centre – Intertidal Rocky Shores³²
Marine Education Society of Australasia – Rocky Shores³³

Field Guides

Graham J. Edgar, Australian Marine Life: the plants and animals of temperate waters, Reed New Holland, 2000.

Keith Davey, A Photographic Guide To Seashore Life Of Australia, New Holland, 1988.