Rarity, market demand, difficulty of breeding.

1. Rarity: The number of Alaska crabs is smaller than that of king crabs, so they are rarer. Rare means more expensive, which makes Alaskan crabs more expensive.

2. Market demand: Alaska crab is particularly popular in the Asian market, especially in China and Japan, where its taste and nutritional value are highly praised. King crab is mainly popular in European and American countries, and its market demand is relatively small. Therefore, the market demand for Alaskan crabs is greater, and the price is higher.

3. Difficulty of breeding: Alaskan crabs are more difficult to breed than king crabs. King crabs can be cultured in relatively shallow waters, while Alaskan crabs require deeper waters and have stricter requirements for water temperature, water quality and other environmental conditions. Therefore, the cost of raising Alaskan crabs is higher, and the price is also more expensive.