Densities of juvenile and postlarval Farfantepenaeus aztecus, F. duorarum,
and Litopenaeus setiferus were compared in vegetated fringing marsh and adj
acent nonvegetated areas over a range of environmental conditions in Mobile
Bay, Alabama. Densities of all three species were significantly greater in
vegetated than nonvegetated areas, with 82% of all penaeids found in veget
ated areas. Among vegetated sites, significantly lower densities were found
in oligohaline areas;, whereas mesohaline areas had the highest densities.
Significant positive correlations were found between density and salinity
for F. aztecus and F. duorarum but not for L. setiferus. Emergent vegetatio
n is important habitat for F. aztecus and F: duorarum as reported from othe
r locations, and our data support a similar conclusion for L. setiferus. Sh
oreline emergent marsh vegetation is particularly important in Mobile Bay a
s it represents the only extensive vegetated habitat readily available to F
. aztecus, F. duorarum, and L. setiferus.