NEUSTONIC NICHE FOR CIRRIPEDE LARVAE AS A POSSIBLE ADAPTATION TO LONG-RANGE DISPERSAL

Fine-scale distribution of cirripede larvae was studied in the second half of July 1979 off the west coast of Brittany, France. The first ten 10 cm layers of water near the surface were sampled, as well as the whole water column. A significant proportion of the cyprid larvae of Verruca stroemia was observed to occupy a neustonic niche, while the vertical distribution of the nauplii was more uniform. This is taken as evidence that, prior to settlement, the late larval stages of this species actively select a near-surface habitat that ensures their dispersal over large areas. The nauplii and cypris were observed at stations near 100 km offshore, much farther than previously reported. The implication of these findings is that the long-distance dispersal of coastal species by meroplanktonic larvae may have been largely underestimated by neglecting to adequately sample the neustonic fauna.