Ck. Dodd, COST-OF-LIVING IN AN UNPREDICTABLE ENVIRONMENT - THE ECOLOGY OF STRIPED NEWTS NOTOPHTHALMUS-PERSTRIATUS DURING A PROLONGED DROUGHT, Copeia, (3), 1993, pp. 605-614
I studied a striped newt (Notophthalmus perstriatus) population for 62
.5 months from 1985 through 1990 at a temporary pond in uplands habita
t of north-central Florida. A severe drought affected northern Florida
during the study, and the pond held water for a total of only 14 mont
hs. Data on size structure, activity patterns, and reproduction are ba
sed on more than 2500 captures. Most newts were captured in 1986 and 1
987 when water occasionally filled the pond. Striped newts entered the
pond any time from late autumn through late spring depending on rainf
all. If water was present, they remained until it dried. If water was
absent, they emigrated but returned if rains occurred later in the sea
son. At Breezeway Pond, larvae transformed only during the spring of 1
987 and few metamorphosed juveniles were captured. The size structure
of the newt population initially was unimodal, but, as the drought con
tinued, the structure shifted toward larger individuals. A decline in
the breeding population occurred from 1988 through 1990 as drought sev
erity increased. I suggest that the lack of a clearly defined sex diff
erential during immigration and the extended annual activity period al
low adult striped newts to maximally exploit temporary breeding habita
ts that are available randomly both within and between years.