Imprecise naming: The anadromous and the sea spawning threespine stickleback should be discriminated by names.

Two ecological forms of the threespine stickleback Gasterosteus aculeatus - a strictly marine form and an anadromous form - are often merged in the literature as a single "marine" form. Because we know virtually nothing of the life style of the two oceanic ecotypes in the sea and consequently nothing on reproductive isolation and gene flow I argue for a precise use of the ecological terms "marine" and "anadromous" for these two ecotypes. These terms should be self-describing. The frequent use of terms incorrectly describing intraspecific variation and life style of ecotypes can bias studies on community composition and interactions of populations.