Fig. 2.

A communal wood frog (Rana sylvatica) deposition site in Concord (Middlesex County) Massachusetts from 1988 (A). Well over 100 egg masses are shown just on the surface, indicating a local population of over 200 breeding adults. Similar numbers bred at this site in the previous 2 years, but in this same time frame only two adults were ever seen outside of the breeding season. (B—F) Breeding sites for boreal toads (Bufo boreas) along Del Peurto Creek in Stanislaus County, California. B shows a pair of copulating toads with the strings of eggs wrapped around the pair. C and D show views of one ephemeral pool where a single clutch of eggs (which can be up to 10,000 individuals) has hatched in 1996. E and F show changes in a second nearby deposition site from 1995 (E) to 1999 (F). The breeding site is on the left in both panels with Del Peurto Creek on the right. Arrow in E shows the location of the small breeding pool shown in panels C and D. Because of anthropogenic activity, water flow has changed at the site, these ephemeral breeding pools have disappeared, and breeding has not occurred here for at least 4 years.