June 14, 2011
A Trove of Marine Life in Monterey Bay
This is part of a series of posts about our Pacific Hotspots expedition.
California Leg, Day 2
This morning after we passed the barking sea lions on the breakwater at the end of the harbor, we traversed through fog so thick there were no signs of land anywhere to be seen. We pushed trough swells upwards of 6 feet to get to our fist dive site of the day. A mola mola (aka ocean sunfish) we passed along the way didn’t seem to mind the intense swells as it basked on the ocean surface.
After motoring out 20 miles across Monterey Bay (north of the Monterey Canyon), we deployed the ROV at the former California halibut trawl grounds. As a direct result of the work of Oceana, this area has been closed to bottom trawling since 2006.
The seafloor here is primarily soft sediment and ranges in depth from 50-250 feet. The areas were teeming with signs of life, including burrows, tracks, and holes. Some places had a lot of juvenile fish and crabs suggesting these areas may be a nursery ground for fishery species. Overall, we were surprised by the diversity of habitat formations and creatures.
We took the ROV to about 100 feet on its first dive of the day, documenting thick clusters of brown sea nettles, which are food for Pacific leatherback sea turtles. This site is excellent habitat for sand dabs (yummy!) and juvenile fish in the depressions between sand waves on the bottom. There were lots of mounds made by invertebrates burrowing in the sand.
At other spots during the day there was so much “marine snow” in the water that we could hardly see and were forced to end the dives early. When “snowflakes” of decaying matter from the upper part of the ocean fall to the seafloor en masse it looks like snow.
The last site of the day was inshore near Aptos, the Santa Cruz side of Monterey Bay. Here we saw large numbers of small dungeness crabs and spot prawns, both burrowing in sand depressions. This soft sediment bottom is also home to several “gardens” of tunicates and sea pens.
In addition to the outstanding footage of the seafloor, Monterey Bay delighted us with glimpses of sea creatures on and above the water including a shy pod of porpoises, a beautiful purple jellyfish, chattering sea otters, and harbor seals.
The crowning glory was a close encounter with a magnificent humpback whale surfacing for air near the starboard side of our eco-friendly sailboat.