http://www.navionics.com/en/webapp
Zoom in on Isla Lobos watch for Campo Encantadas. If you zoom close enough click the symbol in the lower left side of the page and you'll get a foot by foot reading.
see example in pictures.
Some things to note is the black area half way between Isle San Luis and Las Encantadas is a underwater wall. see pinnacles south east of Punta Bufero.
Check it out, there is a lot of structure which will hold fish within easy paddling distance.