[1] Knowledge of cage occupancies and hydration numbers (n) of naturally occurring gas hydrate in a local environment is important for the improvement in global estimates of hydrate-bound natural gas. We report on local differences in cage occupancies and hydration number of gas hydrates from Lake Baikal. Natural gas hydrates of both structures I and II (sI and sII) and ranging in composition from pure CH₄ to mixed gas hydrate containing up to 15% C₂H₆ are compared. The average hydration numbers are n = 6.1 for the sI CH₄ hydrates recovered from the Malenky and Bolshoy mud volcanoes, n = 6.2 for the sI hydrates, containing 3-4% C₂ H ₆ recovered from the K-2 mud volcano, and n = 6.9 for the sII hydrate containing about 15% C₂H₆ recovered from the K-2 mud volcano. The differences in hydration number are due to the differences in the small cage occupancy of CH₄ among the samples studied.