[1] H. californiensis is known for smashing prey against rocks using its raptorial claws, as well as its brightly colored telson and eyespots under the tail.

Mantis shrimps are divided into two groups: smashers and spearers, depending on the method of catching prey.

Smashers use the heel of the dactyl as a hammer to smash open hard-shell organisms, such as clams, crabs, and snails.

H. californiensis is classified as a smasher, using its raptorial claws to smash open its prey against rocks and then eat the organisms soft body inside.

Underneath the tail there are two bright eyespots, which are flashed at predators as a defense mechanism; surprising the attackers and sending them away.

The species appears to produce this rumble by contracting a posterior muscle connected to a stiff extension of the carapace.

[5] It has been suggested that constant and overlapping noise from boats and other anthropogenic sources may threaten the effectiveness of this type of signaling, however little is known about the exact function and to which degree it is impacted by such disturbances.

It was therefore concluded that H. californiensis uses monochromatic vision in its peripheral hemispheres to recognize objects, and the mid-band's sharper color receptors, if light conditions allow, add supplemental information to create a more detailed picture.