1984 - 1986 
Holmquist, J. G., G. V. N. Powell, and S. M. Sogard (1989) Decapod and stomatopod 
communities of seagrass-covered mud banks in Florida Bay: inter- and intra-bank 
heterogeneity with special reference to isolated subenvironments. Symp. on Florida Bay: A 
Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 44(1 ):251-62. 
The decapod and stomatopod fauna of the grass covered mudbanks in five major 
subenvironments of Florida Bay were sampled using throw traps, and the collected 
specimens tested for zonation in these fauna across individual banks. The sampling sites 
were the same as those of Holmquist et al. (1989). Samples were collected three times 
a year in accordance with the ecologically distinct periods of the Bay : December - 
April, May - August, and September - November). The East Central (Cross Bank), 
Atlantic (Buchanan Bank) and Gulf (Dave Foy Bank) subenvironments were sampled 
during 1984 - 1985; the East Interior (bank adjacent to Coon Key) and West Interior 
(between Roscoe and Dump Keys) during 1986; and the Northeast (Eagle Key Bank) 
during 1984 - 1986. The vegetation in these locations was described by Zieman et al. 
(1989) and the decapod and stomatopod communities by Holmquist et al. (1989). Fauna 
was primarily Gulf-Carolinean, despite the presence of a rich Antillean community just 
outside the bay. The two subenvironments adjacent to open ocean had high species 
richness, but banks became increasingly depauperate toward the interior of the bay, 
with the innermost study site supporting a virtual monoculture of the grass shrimp 
Thor floridanus. Species richness was similar across bank tops and exposed and 
sheltered sides. For the majority of species and sites, the exposed sides had the lowest 
abundance of the three transects. Restricted circulation may limit larval recruitment to 
inner portions of the bay, particularly for those species whose adult populations within 
the bay frequently fell to virtually nil, and that physical parameters, especially 
salinity, partially mediate the community structure of organisms that do gain access to 
the Bay's isolated areas. 
1984 - 1986 
Holmquist, J. G., G. V. N. Powell, and S. M. Sogard (1989) Sediment, water level and water 
temperature characteristics in Florida Bay's grass-covered mud banks. Symp. on Florida 
Bay: A Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar, Sci. . 44(1 ):348-64. 
Florida Bay is a shallow lagoonal estuary divided into basins by a latticework of 
mudbanks, which exert a disproportionate influence on the bay ecosystem. The East 
Central (Cross Bank), Atlantic (Buchanan Bank) and Gulf (Dave Foy Bank) 
subenvironments were sampled during 1984 - 1985; the East Interior (bank adjacent to 
Coon Key) and West Interior (between Roscoe and Dump Keys) during 1986; and the 
Northeast (Eagle Key Bank) during 1984 - 1986. The vegetation in these locations was 
described by Zieman et al. (1989) and the decapod and stomatopod communities by 
Holmquist et al. (1989). Prevailing northeasterly winds resulted in distinct sheltered 
and exposed sides on narrow banks, the former with fine sediment and a high organic 
content and the high energy exposed sides with coarser sediment and low organic 
content. Bank water levels were highest in fall. Lunar tidal flux appeared to be directly 
related to the degree of access to open ocean for any given site. Water levels also 
demonstrated some degree of wind-dependency at all sites. Although water levels on 
narrow banks were highly correlated with those of basins, one 2-km-wide bank 
retained a lens of water at low tide despite lower levels in adjacent basins. Bank 
temperatures ranged from 7.5°C to 37.0°C and demonstrated a mean daily range of 
4.5°C, but up to 15°C, in contrast to basin ranges of 1 to 2°C. Temperature range was 
a function of air temperature range and water level. September through November was 
the most benign period on the banks. A bank in the northeastern bay was the physically 
severest of our six study sites. We discuss implications of the physical scenario for 
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