Research School for Socio-Economic and
Natural Sciences of the Environment
Research School for Socio-Economic and
Natural Sciences of the Environment

Joop Coolen

Date: 15 March 2017
Time: 13:30 - 15:00
Location: Aula, building 362, Gen. Foulkesweg 1, Wageningen

Dissertation title: 

North Sea Reefs. Benthic biodiversity of artificial and rocky reefs in the southern North Sea

Group: Wageningen University, Aquatic Ecology and Water Quality Management
Promotors: Prof.dr. H.J. Lindeboom and prof.dr. S. Degraer


Patterns of benthic biodiversity on reefs in the North Sea were investigated. Species natural and artificial reefs were studied, environmental and biotic variables influencing them were assessed. One of the possible pathways for species to colonise reefs was studied; the stepping stone effect.

Conclusions: When rocky reefs on a sandy bottom double local biodiversity. Distributions of the native Caprella linearis and the invasive Caprella mutica differ, demonstrating that they are likely to co-exist in the North Sea. Mytilus edulis presence increases habitat heterogeneity, which increases species richness. Mytilus edulis uses offshore structures as stepping stones to colonise locations in the North Sea that cannot be reached in a single generation. Depth and location influence the species composition on artificial and natural reefs most strongly. When artificial reefs are to be colonised by communities that are similar to natural reefs, their structures should resemble natural reefs as much as possible.