[9] Kelletia kelletii is found from Isla Asunción, Baja California, Mexico, to Monterey, CA, USA.

[2] Studies suggest that the Kellet's whelk range expanded to Monterey Bay in the 1970s or early 1980s, possibly due to an El Niño event, and is dependent on recruits from southern California.

[7] Often in subtidal areas large numbers of Kelletia kelletii have been observed moving towards and/or feeding upon one food item.

[7] As a predator Kellet's whelk feeds on dead or alive polychaetes, bivalves, sea snails, crustaceans, ascidians.

[7] The proboscis is capable of extending approximately twice the length of the whelk's shell; it is this extension which allows Kelletia kelletii to reach food items in depressions or within the substratum.

[7] Kellet's whelk has been observed feeding together at the same time with the Giant sea star Pisaster giganteus on common food items and thus these two species are trophically interrelated.

[7] Pisaster giganteus also preys on Kelletia kelletii more often than any other motile gastropod, and yet the whelks do not appear to be eaten in proportion to their abundance or accessibility in studied localitions.

[7] Coexistence between the two species is believed possible as long as Kelletia kelletii does not become a preferred prey of the sea star.

Kelletia kelletii has also been observed feeding interspecifically with two other sea stars, Dermasterias imbricata and Pisaster brevispinus.

[9] Kellet's whelks reproduce annually, with egg-laying restricted to late spring and summer (in March, April and May).

[9] In a year-long tagging study in southern California the majority of the 188 animals recaptured showed no growth at the end of the year.

[9] Predators of Kelletia kelletii: Shells of Kellet's whelks have been found in archeological and paleontological sites in southern California.

[9] The average weight of a Kellet's whelk in a fishery is 150 g.[13] The food-finding ability of Kelletia kelletii by distance chemoreception has, on more than one occasion, been a nuisance to spiny lobster fishermen in some areas off southern California.

[7] Since 1979, 89 percent of all harvested Kellet's whelks have been taken incidentally in lobster and crab traps when they enter to prey on bait or on injured crustaceans.

[9] Recreational take of Kellet's whelk by hand is allowed (Title 14, CCR, §29.05) outside of the 1,000-foot (300-meter) tidal invertebrate zone.