Drill-cored rock pools: an effective method of ecological enhancement on artificial structures

  • Published source details Evans A.J., Firth L.B., Hawkins S.J., Morris E.S., Goudge H. & Moore P.J. (2016) Drill-cored rock pools: an effective method of ecological enhancement on artificial structures. Marine and Freshwater Research, 67, 123-130.


This study is summarised as evidence for the following.

Action Category

Create 'rock pools' on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures
  1. Create 'rock pools' on intertidal artificial structures

    A replicated, paired sites, controlled and site comparison study in 2012–2013 on an intertidal breakwater on open coastline in the Irish Sea, UK (Evans et al. 2016) found that rock pools created on the breakwater supported higher macroalgae, invertebrate and fish species richness than breakwater surfaces without pools, and similar species richness but different community composition to natural rock pools. After 18 months, a total of 23 macroalgae, invertebrate and fish species were recorded in created pools and 14 on breakwater surfaces without pools (data not statistically tested). Community composition (data reported as statistical model results) and average species richness was similar in deep and shallow created pools (both 8 species/pool), and richness was higher in both than on surfaces without (6/surface). Twenty species (7 macroalgae, 6 mobile invertebrates, 6 non-mobile invertebrates, 1 fish) recorded in pools over 18 months were absent from breakwater surfaces. Species richness and the mobile invertebrate and fish community composition were similar in created and natural pools, but the macroalgae and non-mobile invertebrate community composition differed (data reported as statistical model results). Rock pools were created in April 2012 by drilling into horizontal surfaces of a granite boulder breakwater using a core-drill. Nine deep (depth: 120 mm; volume 2.1 l) and nine shallow (50 mm; 0.9 l) cylindrical pools (diameter: 150 mm) were drilled at midshore. Pools were compared with breakwater surfaces on horizontal and vertical boulder surfaces adjacent to each pool, with surface areas matching the inside pool surfaces (deep-vertical: 230 × 230 mm; shallow-vertical: 150 × 150 mm; both-horizontal: 130 × 130 mm; A. Evans pers. comms.), and also with natural rock pools on three nearby reefs. Both were pre-cleared of organisms. Macroalgae, invertebrates and fishes were counted in pools and on breakwater surfaces during low tide over 18 months.

    (Summarised by: Ally Evans)

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