This is a cluster, or clutch, of eggs deposited by a yellowfin madtom
female. A typical yellowfin madtom egg clutch contains 75 to 200 eggs. The
male defends a cavity under a slab rock two to four feet in diameter.
Females are attracted by scent to the "nest rock," lay their eggs, and
swim away. The male stays and guards the eggs from predators until they
are hatched.