Life expectancy is about 14 years maximum.
Adults feed on clams and other snails which they either drill with the rasping radula or suffocate. Drilling is assisted with an organ that produces enzymes and hydrochloric acid to weaken the shell of the victim.
Drilled holes are countersunk which distinguishes them from holes drilled by other snails or octopuses.
Drilling rate is about 0.5mm per day and the process of eating the prey take about a day. Moon Snails favor soft or thin shelled clams and avoid the thick shell Heart Cockles. In turn Moon Snails is fed upon by Sunflower Stars, Red Rock Crabs, gulls, octopuses, and when small, Northern Clingfish and likely other fish.
While some people do eat Moon Snails, certain First Nations peoples of Canada did not as they were said to make the eater stupid. Since Moon Snails feed on clams which may contain toxins that can affect brain function this seems like quite good advice...Don't eat them.
If one closely examines the concave surface of a sand collar on the beach it becomes evident that lots of things are using it to lay eggs, perhaps as cover, or feeding on the Moon Snail eggs. Some of the items found are tiny and difficult to identify which makes it all the more interesting....if sometimes frustrating for anyone who wants to know it all. Images below show some of the action on the collar surface.
SAND COLLAR STUFF (many of these are 1cm or less in size)
|Lacuna snail on sand collar|
|Dove Snails on sand collar|
|Barnacle Eating Sea Slug on sand collar|
|Opalescent Sea Slug|
|Barnacles on sand collar|
|Top Snail on egg mass on sand collar|
|Unidentified worm on sand collar|
|Top Snail on sand collar|
|Moon Snail with sand collar|
|Moon Snail with clam victim|
|Moon Snail making sand collar|
|Moon Snail siphon on surface collecting air|
|Moon Snail damaged shell from gull attack|
|Moon Snail drilled clam|
|Opalescent Sea Slug eggs|
|Hansine's Sea Slugs eating Opalescent Sea Slug eggs (?)|
|Phyllodoce williamsi Worm eggs|
|Olea hanisneensis sea slug eating Opalescent Sea |
|Olea hanisneensis sea slug on sand collar|
|Lacuna snail and eggs|
|Opalescent Sea Slug Ho Down|
|Flatworm with flatworm eggs on sand collar|
|Unidentified snail on sand collar|
|Teamwork, Olea Sea Slug style|
|Lacuna with decaying seaweed wit|
h unknown white pattern