Rock Pool Animals
As you walk over Wave Rock - take time to look into the rock pools - they are abundant with life. There has been over 60 species of invertebrates and tadpoles of several different frog species found to date. Many of these are in similar pools on other granite outcrops across the wheatbelt, though there is one species, a beetle, not yet found on any other rock.
The animals in these pools can be divided in two large goups, depending on how they survive the dry periods of these pools. The first group such as the crustaceans and worms, survive the long dry periods over summer as resistant eggs in the sediments of the pools. The second group, mainly the insects and frogs, once they are adult can leave the pool and survive dry times elsewhere. They will invade the pools as they fill with water, usually in late autumn and winter. The animals in the second group prefer larger and deeper pools which hold water for longer, otherwise their larval stages will not mature before the pools dry and hence breeding is unsuccessful.
The most conspicuous invertebrates of rock pools are the fairy shrimps and clam shrimps. Like many of the crustaceans, the species on Wave Rock only occur in rock pools. Fairy shrimps are active swimmers, where as the clam shrimps are slower. All shrimp eat microscopic algae.
The bottom sediments are usually teaming with life, mainly very small water fleas and seed shrimps. Altogether 13 species of water fleas and 12 species of seed shrimps have been found on Wave Rock, but there are only a few species in any one pool.
As wheatbelt waters salinise, freshwater pools are becoming scarce and the pools on granite outcrops are growing in importance for the survival of all of these animals. Fortunately, the rock pools on Wave Rock are in good condition.