158 visual censuses involving timed swims,
using closed circuit rebreathers, were carried out at tyre, vessel,
quarry rock and concrete ARs and four other control sites between March
1999 and December 2000.
Comparing the observed fish
abundance and diversity at the study sites, the following conclusions
1. ARs deployed on mud bottom support a more abundant and diverse fish
population than mud bottom alone.
2. Rocky shore control sites have similar diversity to ARs but less
3. Artificial reefs support higher value fish than rocky shore and mud
bottom control sites.
4. Quarry rock ARs become colonized with fish more rapidly and have
higher abundance and diversity than other types of ARs.
5. No apparent differences between abundance found on tyre-, concrete-
and vessel ARs.