The Delta smelt saw a tenfold increase this year thanks to lots of freshwater flow through the estuary, officials said today.

We’ll have a story in the paper and online Thursday. In the meantime, here’s the Department of Fish and Game memo, with charts showing the abundance of five fish species since the late 1960s.

And here’s a snapshot of the numbers (this is an index, not the literal number of fish in each population):

This year       Last year        Historic high

Delta smelt:               343                  29           1,673 (in 1970)

Striped bass:              272                  43           19,677 (in 1967)

Longfin smelt:            477                 191           81,737 (in 1967)

Threadfin shad:          228                 120           15,267 (in 1997)

American shad:          894                  683           9,360 (in 2003)