Intertidal Community Regulation Figure 3. Mussel recruitment rates (mussels per collector per day) at R-R and R-S sites. From north to south (a) Leigh area sites, (b) Mt. Maunganui sites, (c) Banks Peninsula sites. Open symbols/dashed lines designate R-S sites and full lines / black symbols designate R-R sites. For Banks Peninsula sites we used data from a previous experiment [27] because in the current study we only used no-cage treatments in this region (not allowing the measurement of effect-size) but the results from the two experiments show very similar trends. doi:10.1371/journal.pone.0023958.g003 influence recruitment rates (this study; though the relationship turned out to be negative in this case). In New Zealand, a comparative study on both sides of the South Island did suggest a strong coupling between coastal oceanogra- phy, mussel recruitment rates and predation pressure by sea stars [15]. In the same system, we show in this study that the recruitment-predation link is not general but rather highly context- dependent if the full suite of other predators that feed on smaller individuals is considered. We were also able to identify the mechanism responsible for the observed negative relationship between prey recruitment and predation intensity by showing that the levels of both processes depends on the characteristics of the reef seascape. The results for the current study indicate that predation intensity was a stronger predictor of the abundance of adults of a dominant space occupier (mussel beds) than recruitment rates. Accounting for seascape in the study produced a negative correlation between mussel recruitment and predation intensity on small mussels. Rocky intertidal sites with low mussel recruitment and high predation intensity, and vice versa, exist, as do intermediate combinations (i.e., high-high or low-low, Fig. 4). The major predators on small mussels on the east coast of New Zealand are reef-dwelling labrid fish that are abundant on subtidal reefs at sites where intertidal mussels have very low recruitment levels and are extremely rare (e.g., KP, MM1). The consequence of this discrepancy is an intense and rapid predation on small mussels by these highly mobile predators, which eliminate the few mussels that manage to settle and grow to a juvenile stage at such R-R sites. This swift predation on small mussels can easily be overlooked in studies without fine-scale temporal resolution of post-recruitment predation. Notably, although we found some general patterns and processes at sites with similar seascapes (R-R PLoS ONE | www.plosone.org 7 August 2011 | Volume 6 | Issue 8 | e23958