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The active delta of the Mississippi River was sampled in August 1968 to determine plant species composition, plant· coverage, and soil and water chemistry. Hurricane Camille struck this area in August 1969, with winds in excess of 200 km/h and tides ranging upward to 5.2 m above MSL. The delta was resampled 2 weeks following the hurricane to evaluate the immediate effects on vegetation, soil, and water, and again 1 year after the hurricane to determine the recovery rate of vegetation.The hurricane resulted in a drastic reduction of vegetation. Regrowth was rapid in the delta marshes and after 1 year plant coverage approached pre-hurricane levels of abundance; however, recovery was slower in ponds and lakes. The loss of vegetation was mainly a result of the sweeping action of wind and water, and plants were either uprooted or ripped apart and carried away by the current. Water salinity increased with the hurricane but declined by the following year and appeared to have only slight effect on marsh vegetation.Plant species varied in their response to the hurricane. Bacopa monnieri showed practically no effect, and Phragmites communis and Spartina alterniflora were reduced only slightly. Myriophyllum spicatum, Panicum repens, and Alternanthera philoxeroides were greatly reduced by the storm; and after I year, only Alternanthera philoxeroides showed significant recovery.

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Nutria (Myocastor coypus) and muskrats (Ondatra zibethicus) are the predominant food items of alligators over 1.5 min length in southeastern Louisiana. Our data and a review of the literature on alligator diets indicate that the mammals are apparently major components of the diet of large alligators over much of their range, with fishes and crusta• ceans being more important to smaller alligators.

The Louisiana coastal marshes form some of the most extensive wetlands within the continental United States. The problem of land loss in these coastal marshes is well-documented, but very little is known about possible changes in vegetation composition that might be associated with this loss. We analyzed vegetation data collected from 1968 to 1992 in the tidal wetlands of Terrebonne parish and described five vegetation types that occur in this region. Our data did not show the predicted change to more salt-tolerant vegetation. This is probably due to the influence of the Atchafalaya River in the study area. However, we documented a large change in the dominant vegetation of the fresh marsh. Panicum hemitornon-dominated marshes occupied 51% of the study area in 1968 and only 14% in 1992. This vegetation type was replaced with Eleocharis baldwinii-domJnated marshes (3% in 1968 to 41% in 1992). This change occurred adjacent to an area of significant conversion to open water. Based on limited available data from the literature, we ev',duated three potential driving factors in this change-grazing, water-level increase, and water quality-but could not determine the cause of change definitively.

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