the drift. Hundreds of these were carried to the mainland where they were left along the shore 
or hanging in the brush. 
Hurricane Donna profoundly altered some of the physical features of the area. A deposit of silt 
varying from a trace to 5 in. was carried over the area inundated by the tidal wave. The 
deposit was heavier in the denser vegetation near the shore, building up the coastal flats of the 
mainland and adding to the higher rim characteristic of the Florida Bay keys. This deposit is an 
important factor in raising the elevation of the land formation of the coastal prairie and 
hammocks and especially the Florida Bay keys, some of which are 18 to 24 in. higher than the 
interior land. An appreciable deposit was left in the coastal mangrove areas where 2 to 5 in. 
elevation is an important factor in the encroachment of other plant species into this type. This 
deposit is high in nutritive values as indicated by the luxuriant growth that developed on it 
during the months following the storm. On some exposed keys and coastal hammocks the entire 
humus deposit and surface soil was removed and the debris carried inward to form a moraine 
2-5 ft high where the vegetation acted as a barrier. This will stimulate hammock formation. 
Some smaller keys were practically obliterated. Sandy Key was cut in two, and Cape Sable 
beaches were altered considerably. Inland, practically all the small mangrove creeks and canals 
were clogged with wind thrown trees. The Bear Lake Canal, formerly 4-6 ft deep, was filled to 
within 6-12 in of the surface with organic deposit from the mangrove forest and marl from the 
Bay. This action will hasten the obliteration of those creeks where the currents are not strong 
enough to prevent further deposits of humus and silt. Many such filled creeks were present in 
the mangrove belt. 
Many of the Florida Bay keys have moats up to 10 ft deep and 50 ft wide on the northeast, east 
or southeast side directly against the mangrove fringe. Dildo Key is nearly surrounded by such 
a moat. Craighead and Gilbert (1962) attributed these moats to the action of storm waves 
beating against the solid wall of mangroves and scouring out the marl down to the Miami oolite 
bedrock. 
Tabb and Jones (1962) studied the mortality of aquatic animals caused by Hurricane Donna. Fish 
and invertebrates were stranded by retreating salt water which had been driven inland or were 
killed by mud suffocation or turbulence. Oxygen depletion due to decomposition of organic 
material caused subsequent mortality. Salinities returned to normal within 6 weeks, but 
dissolved oxygen concentration remained abnormally low for a longer period. When 
environmental conditions again became suitable, the stricken areas were recolonized from 
surrounding regions. Sport fish catches in the area declined immediately after the storm, but 
recovered within one to several months, depending on the locality. Catch statistics indicate that 
after the storm juvenile pink shrimp moved from their estuarine nursery grounds into deeper 
water about 60 mi offshore, where they were caught by the fishery. There is no evidence that 
the aquatic fauna of the area suffered any permanent damage. 
Hurricane Andrew passed over Homestead August 24, 1992. Andrew was a relatively dry 
hurricane, with strongest sustained winds of 144 mph. The hurricane passed directly over 
Biscayne Bay and had little effect on Florida Bay. The effects of this storm on Biscayne Bay and 
the northern Florida Keys have been described in several works (Blair et al., 1994; Bohnsack 
et al., 1994a; O'Brien et al., 1994; Meier and Porter, 1994; Meeder et al., 1994; Milton et 
al., 1994; Pimm et al., 1994; Smith et al., 1994; Tilmant et al., 1994; and others) 
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