Congress (salamander gathering)

Oxford English Dictionary defines congressing as "The action of coming together... a sexual union, copulation, coition."

The congressing event takes place each spring and this migration of salamanders to vernal pools and is known as the Big Night.

[3][4] The reason it is referred to as a big night is because there is a large number of salamanders moving at the same time.

Warmer air and loose soil coupled with rain cause salamanders to leave their underground burrows.

[5][3] Salamanders are explosive spawners and the females lay thousands of eggs which they attach to sticks below the water.