BULLETIN FLORIDA STATE MUSEUM


 BIRDS

 The results of bird transects are summarized in Tables 7-10. A total of
150 species was observed in the mining region during the study, and 114
were recorded from the 24 discrete study sites.
 CONSOLIDATED CLAY SETTLING PONDS.-In this treatment, both
abundance and diversity values were low compared with the other seven
treatments (Fig. 19). Most of the avifauna on these sites consisted of
resident passerines that usually were associated with brushy habitats,
including gray catbird, white-eyed vireo, common yellowthroat, red-
winged blackbird, cardinal, and rufous-sided towhee. Only six non-pas-
serine species were recorded from the treatment, and wading and water
birds generally were absent. Two wetland species, common moorhen
and common snipe, were seen in the Swift site, which was the wettest
and least consolidated of the three. The low bird diversity and abun-
dance of clay waste sites probably was related to the uniform and simple
structure of the vegetation.
 Most of the species in this treatment were permanent residents, and
the bird community showed very little seasonal variation in either diver-
sity or abundance (Tables 7-10). The abundance values in particular were
low and remained low through the winter, when other categories of sites
were used by flocks of either warblers (unreclaimed pits) or sparrows
(reclaimed sites). Though non-resident wintering birds heavily used wax
myrtle on unreclaimed sites, wintering birds were scarce on consolidated
clay settling ponds despite abundant wax myrtle. Evidently an important
component was lacking. Low amounts of insect biomass (Table 11) may
have resulted in a short supply of protein for insectivorous or seasonally
omnivorous birds.
 UNRECLAIMED PITS AND SPOIL PILES.-In the successional se-
 quence, the diversity and abundance measures increased with increasing
 age of the site but, unlike the small mammal data, reached their peak at
 a much later stage-either the 15-30 year class or the >30 year old class
 with lakes (Fig. 19).
 The youngest class, 0-5 years old, was distinctly different from the
 older stages, with lower diversity and abundance measures as well as
 different species composition. This undoubtedly resulted from the early
 stage of oldfield succession on these sites. In some respects the avifauna
 on these young sites resembled that found on reclaimed pastures, with
 savannah sparrows, palm warblers, killdeer, and other shorebirds being
 common in both categories. In addition the lakes on these sites attracted
 the largest diversity of waterfowl of the eight categories. Nine species
 were observed there, compared with only three in the 5-15 year old
 pits. The reason for the high use by ducks is unclear. One possible expla-


VOL. 30 NO. 3