Undersea forests of California's Channel Islands

The engine falls away to an idle, rousing me from slumber below deck. We are approaching our first dive site after a three hour journey from Ventura in southern California.

After boarding the boat the previous night, the skipper cast off at 3 am and it is now 6.30 am, the sun is rising along with our excitement levels with the prospect of what is to come.
Though situated in 20 metres of water tucked in behind Gull Island, the kelp is matted thickly on the surface. Californian sea lion heads pop up intermittently. “Gates are open” is the call from the skipper, and he needn’t say it twice. We giant stride into the giant kelp below, and it’s really quite something being immersed in the three dimensional maze of kelp; those first moments flying through an undersea forest are forever etched in my mind.

In 1980, Congress designated Anacapa, San Miguel, Santa Barbara, Santa Cruz and Santa Rosa Islands and 125,000 acres of surrounding waters, a national park, because they possess unique natural and cultural resources. Boy, did Congress get that one right!

Those named are five of the eight Channel Islands in southern California, home to a breath-taking array of animal diversity and colour. Though tantalisingly close to major populations centres along California’s coastline, the Channel Islands isolation and the protection of their national park status has kept them largely undeveloped.

The first things that stand out are the giant kelp itself, and the legions of sea lions darting in and out like fighter pilots. But we quickly come to see there is an extremely rich diversity here. Other iconic animals are easily seen, such as the state fish of California, the gaudily coloured garibaldi. The sheephead wrasse is another famous inhabitant, and in the protective waters of the marine reserves, these distinctive, bold black-and-red predators often come in close for a curious look. Sheephead fill a similar ecological role to our own snapper in New Zealand, feasting on sea urchins, and in doing so allow the kelp to flourish.

We dived both inside and outside no-take zones, and whilst there were dozens of very large sheephead on each dive inside, we failed to see a single large adult outside! This at dive sites just a couple of kilometres apart.

Due to the structure of the kelp reaching from seafloor to surface, the extra habitat it affords greatly increases the number of fishes finding shelter here. It also provides an opportunity for different species to find their own unique niche; the sheer diversity is testament to this. We see kelp bass hovering amongst the fronds, schools of opaleyes (like our parore) and seaperches soaring through the canopy. Shoals of blacksmith – the two-spot demoiselle equivalent of the Channel Islands – gather en masse. Mini cigar-shaped wrasses called senoritas fill one’s vision at every turn

Perhaps my favourite were the many flavoured rockfishes (Sebastidae), if nothing else than for their variety. This family of fishes, closely related to the scorpionfish, has undergone a remarkable adaptive radiation, with around 130 species found up and down the west coast of America and Canada. We would easily have counted 15 different species over the course of our few dives.

Invertebrates also take advantage of this immense structural haven. Crabs and gastropods abound in many of the kelp’s surfaces, feeding off the kelp itself or the plethora of mini crustaceans harboured by it. The deep ocean is not far away from the outer side of the islands, with pelagic animals often seen on clear days. Ocean sunfish, dolphins and soupfin sharks were all sighted by our liveaboard party during the trip

Liveaboards are certainly the best way to maximise any dive trip in terms of the time they allow underwater, this trip being no different. Twelve dives over two days is certainly bang for buck! And there are no shortage of options at either Ventura or Santa Barbara.

Liveaboards also offer the opportunity for a night dive, accompanied by Avatar-like phosphorescence! The northern hemisphere’s late summer and autumn are probably the best time, when the water is at its clearest, and the weather is more reliable with minimal winds. Autumn water temperatures are relatively warm (16–19°C), and ok in wetsuits. However, in these rich temperate seas I was glad to be in my drysuit to maximise the multi-dive days on offer.

While we made the most of our two days at the islands, the trip left me longing for more. Perhaps next time a camping trip on the islands combined with another liveaboard is the ticket!

Information for visiting divers on California's Channel Islands

Getting thereLos Angeles to Ventura, from where many charter boats operate, is a 90 minute drive.

Best time of year
The Channel Islands can be dived year round though conditions are at their best in late summer and autumn.

Weather
Summers and autumn are warm, with rainy, stormy days in winter, and decent swells. Average day time temperatures mirror water temperatures of 8–12°C in winter to 20–25°C in summer. 95% of the rain falls between November and April.

Visibility
Water visibility ranges from 5m to 25m or more, as dictated by currents and storms, and also seasonal plankton growth. Best visibility is during settled weather and after the summer plankton bloom subsides, around August or September (reliably 10-15 m +).

Water temp
Temperatures range from 10–12°C late winter to 20–21°C late summer, with coolness due to the upwelling system near Pt. Conception. Note: the water is warmer at the southern Channel Islands south of LA.

About Paul Caiger

Paul Caiger contributes Dive magazine’s Species Focus, a marine biologist who is passionate about the oceans, its inhabitants, and pretty much nature in general. He completed his post graduate studies at the Leigh Marine Lab adjacent to New Zealand’s first marine reserve at Goat Island where he spent a lot of time because he found it such a hard place to leave!

He is currently based in Woods Hole in the NE of the US, where he has an 18 month research contract with NOAA’s Northeast Fisheries Science Center studying the acoustic behaviour of Atlantic Cod. Paul has dived in temperate and tropical seas around the globe but says the Poor Knights rival any destination.