1987 SCHNOES AND HUMPHREY: TERRESTRIAL COMMUNITIES IN FLORIDA 79


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 Figure 17.-6-D, the pasture with the least plant cover among Reclaimed, Grazed
sites. Reclamation here involved filling in old mine cuts with fine sand tailings (resulting
fiom recent flotation treatment of ore) and then flattening emerged spoil pile tops as a
shallow overburden cap. Vegetation is bahia grass with some hairy indigo and rattlesnake
weed in the foreground.


 Additional species of small mammals established populations in the
5-15 year old treatment (Fig. 18), resulting in very high values. The
population of Mus declined somewhat between the 0-5 and 5-15 year
classes, but the major change was a substantial increase in the abundance
of Sigmodon, P. gossypinus, and Oryzomys. Both events were normal
responses to the increase in plant cover, particularly herbaceous species
and vines. The pattern of increasing abundance was accompanied by similar
increases in diversity, because most populations continued to grow and a
new species (the eastern woodrat, Neotomafloridana) invaded.
 In later seral stages, the small mammal community became less prom-
inent, with moderate diversity and abundance levels. Mus became very
uncommon and population levels of Sigmodon and Oryzomys fell. P. gos-
sypinus populations remained fairly constant, whereas Neotoma became
slightly more common. The reduction of Mus populations probably was
caused by changing habitat characteristics, resulting from development
of shrub and tree vegetation, and possibly by increased competition from
other small mammal species. The drop in Oryzomys numbers may have