Estimation in situ d'une population d'Oikopleura longicauda (Appendicularia) à l'aide de deux filets de maille différente

A population of Oikopleura longicauda was sampled daily for 10 days, a period longer than their life cycle, using two nets of different mesh size (53 and 200 m). Analysis of variance revealed that the number of specimens collected by the two nets was not significantly different for individuals larger than 300 m in trunk length. A grand mean regression plotted for log of length versus log of number of specimens indicated that the number of small-sized O. longicauda (<300 m), which are not quantitatively sampled by nets, can be estimated from the collections by use of a coefficient of correction.