LIU, HONG1*, STEVE G. PLATT2, and CHRIS K. BORG1. 1Department of Biology, Florida International University, Miami, FL, 33199; 2Wildlife Conservation Society, 2300 Southern Blvd., Bronx, New York, 10460-1099.. - Seed dispersal by the eastern box turtle (Terrapene carolina ) in subtropical pine rockland of the Lower Florida Keys.
Animal seed dispersal is one of the most common plant-animal
mutualisms in nature and plays an important role in plant
distribution. Yet little is known about seed dispersal by reptiles. In
this research, we investigated the role of the eastern box turtle as a
seed dispersal agent in subtropical pine forests of the Lower Florida
Keys. We searched for box turtles in pine rockland on Big Pine Key
during 1999 to 2001. We returned captured turtles to the lab for one
day and collected their feces. Seeds of 9 species were recovered from
the feces, all of which have fleshy fruits and are capable of
germination. Comparative germination experiments were conducted for up
to two years with seeds of three prevalent species found in the turtle
feces. Passage through the box turtle gut greatly enhanced the
germination rate and percentage of Serenoa repens, but
decreased the percent germination of Byrsonima lucida and
Thrinax morrisii. Subsequent destructive seed viability tests
showed that up to 60% of the ungerminated seeds were still viable,
suggesting long-term seed dormancy, even after passing through the
turtle digestive system. Removal of fleshy pulp by the turtle
digestive system seems to provide an escape from seed predation for
seeds of Thrinax morrsii.
Key words: Serenoa repens, Thrinax morrisii, Byrsonima lucida, Florida Keys, seed dispersal, seed predation, Terrapene carolina