Historical Records for the Main Vernal Pool at the Santa Rosa Plateau

This page presents my historical data on when the Main Vernal Pool first appears, fills, and when it dries up completely, along with depth at formation and maximum depth during its lifetime. Fairy shrimp reproduction was successful in all years except 2006, when most of the fairy shrimp died after the shallow initial pool dried up except for a few puddles. No new shrimp hatched when the pool refilled later that year.

The median date of filling is mid-February, but the pool has filled as early as October 20 and as late as February 28. The median depth at initial filling is 6 inches; in most years the pool eventually fills to its maximum depth of 16 inches. The median duration of the pool is four months, and varies from 2.5 to 8.5 months.

Rainfall YearFormation DateDisappearance DateLifetime (days)Depth at Formation (inches)Max depth (inches)Successful fairy shrimp reproduction
1998-1999no pool
2001-2002no pool
2006-2007no pool

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Copyright © 1996-2008 by Tom Chester.
Permission is freely granted to reproduce any or all of this page as long as credit is given to me at this source:
Comments and feedback: Tom Chester
Updated 14 January 2008.