A special surveillance zone of overlapping tidal excursion
zones has also been established.
Period (Pi) and tidal excursion
(Ti) were calculated for each constituent from amplitudes (Ai) and frequencies of the constituents as follows:
The mean current magnitude is dependent on the ratio of the width of the sloping region to the distance that a particle travels in half a tidal cycle (the tidal excursion
, approximately 14 kilometers for a tide of 1 meter per second), and is strongest when these two length scales match.
Within the estuary, juvenile white shrimp, in contrast to other penaeid species, are found across a wider range of environmental conditions and habitats (Kutkuhn, 1966) and often make tidal excursions
between subtidal and vegetated intertidal habitats to forage (Mayer, 1985; Kneib, 1995; 2000).