Comparing Stone Crabs vs. Dungeness Crabs
Dungeness Crabs vs. Stone Crab Crabs: Size and Identification
Dungeness crabs are slightly larger than stone crabs, averaging 8 – 10 inches in width and 32 to 48 ounces in weight. In contrast, stone crabs measure 5.5 to 6 inches in width and 3 to 7 ounces in weight. As for distinguishing visual characteristics, Dungeness crabs are typically yellow-brown to purplish, with four pairs of walking legs and pincers with light-colored tips. In addition, they have sharp serrated teeth on their claws and distinctive hooks at their end, which help them identify from other similar species. Alternately, stone crabs are as they suggest; stone-colored (light reddish brown) with brown spots that give them an earthy appearance. In addition, these crustaceans have black-tipped pincers for grabbing onto whatever they are going after — whether plant or animal tissue.
Habitat and Location
The Dungeness crab and stone crab are abundant in the Pacific Northwest. Specifically, the Dungeness crab lives in areas around California through to Alaska. The stone crab mainly inhabits the waters around Florida. More precisely, the Dungeness crab and the stone crabs prefer sandy or muddy bottoms in shallower saltwater environments. However, the Dungeness’s tolerance to salinity changes, so the water depth and its ability to survive in estuarine environments distinguish it from the stone crab. Therefore, you can expect to see stone crabs in bays, oyster reefs, and rock jetties where they can burrow or find refuge from predators.
Dungeness Crabs vs. Stone Crabs: Diet
Dungeness crab diets can vary greatly depending on what is available. But, Dungeness crabs are predators and scavengers, so they will happily eat clams, small fish, or other crustaceans if they can find them. This varied diet ensures that the Dungeness crab is never short of food, no matter the season. However, the adult stone crab is primarily a mollusk eater, with mussels being their preferred prey. But, they will also consume acorn barnacles, which can be found in large numbers on California beaches during autumn.
Lifespan
Dungeness crabs can live between eight and 13 years and reach sexual maturity at three years. In contrast, stone crabs have a shorter lifespan of seven to eight years but reach sexual maturity at about two years. Once they reach adulthood, both species can produce large numbers of offspring. To understand these differing lifespans, you need to consider the habitats and lifestyles of these crabs. Dungeness crabs live in habitats ranging from estuaries to open coasts. In contrast, stone crabs live almost exclusively in shallow coastal waters. In addition, Dungeness crabs are omnivores that feed on various plant and animal matter. On the other hand, stone crabs are mainly carnivorous, feeding on small fish and invertebrates. These different lifestyles and diet choices help to explain the varying lifespans of these two types of crabs.
Interesting Habits
In contrast to popular belief, Dungeness crabs do not bury themselves to suffocate their prey. Instead, they use this strategy as camouflage. While burying themselves, they can keep from choking due to hairs above water intakes at the bases of their claws. These hairs keep the gill chamber free of sand grains. In addition, these same water intakes allow the crab to breathe while buried. In short, the Dungeness crab has adapted to its environment to survive better. The stone crab also has some interesting habits. Its primary method of communication is visual signaling. Before engaging in an intraspecies confrontation, a stone crab will openly display its massive claws. The larger the claws, the more likely that the stone crab will be able to claim the local ideal breeding habitat. If one stone crab notices another engaging in a successful confrontation, it will immediately attempt to flee the area. These visual displays are essential for the stone crab’s survival; without them, the species would quickly become extinct.
Predators
In addition to humans, stone crabs have several natural predators, including horse conchs, sea turtles, and octopuses. Likewise, their Dungeness counterparts are the prey of halibut, dogfish, sculpins, and other crabs. Sea otters are also known to eat both types of crab. However, humans remain the biggest threat to both species. People frequently harvest stone and Dungeness crabs for their meat. As a result, these animals risk becoming endangered if the authorities do not manage them sustainably. The stone crab is one of the few examples of living creatures that fishermen do not kill during harvesting, instead only breaking off their claws. This strategy is valuable as once fishermen return them to the water within an hour, the claws will regrow within 12 to 18 months.
Up Next
Oyster vs Clam: 7 Main Differences ExplainedClams vs Mussels: 6 Main Differences ExplainedSnail
