The Friends of James River Park included a cool photo (at left) with their most recent e-newsletter. Those white blobs are egg masses of the spotted salamander. According to wikipedia.org:
During the majority of the year, Spotted Salamanders live in the shelter of leaves or burrows in deciduous forests. However, when the temperature rises and there is a higher moisture level, the salamanders make their abrupt migration towards their annual breeding pond. In just one night, hundreds to thousands of salamanders may make the trip to their ponds for mating. Mates usually breed in ponds when it’s raining in the spring.
Ralph White, former JRPS manager, once described the spectacle to the Virginian-Pilot: “We do the best we can for safe salamander sex,” he said. “Males wait for a real gully-washer. Then it’s like going down to Fort Lauderdale: Where are all the chicks? Where’s all the action? They go running down the hillsides and some move along the road, because they can go faster.”
These masses are in a vernal pool along Riverside Drive upstream from Pony Pasture Park. According to the Friends: “The pool, maintained by Park staff, will remain full for the mating and larval season and drained before mosquito season!”