Traveling night and day, the gray whale averages approximately 120 km (75 mi) per day at an average speed of 8 kilometers per hour (5 mph). This round trip of 16,000–22,000 km (9,900–14,000 mi) is believed to be the longest annual migration of any mammal. By mid-December to early January, the majority are usually found between Monterey and San Diego, often visible from shore. The whale watching industry provides ecotourists and marine mammal enthusiasts the opportunity to see groups of gray whales as they migrate.

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