'They were coming from all directions, you could see them from as far as the eye can see,' Joe Dutra said after seeing the spectacle first hand.
Mr Dutra, who captains Hornblower Cruises, was out on his daily tour with a boat full of nature watchers when he spotted the massive group of dolphins.
'I’ve seen a lot of stuff out here… but this is the biggest I’ve ever seen, ever,' he told the local NBC affiliate.
Dolphins typically travel in groups of anywhere between 15 and 200 which are called pods.
http://www.dailymail.co.uk/news/article-2280236/Mystery-group-100-000-dolphins-spotted-swimming-coast-San-Diego.html