Life Down Under: Eelgrass Meadows

One of my favorite leisure activities  is scuba diving. The nearshore of Yellow is dominated by eelgrass, Zostera marina. On nearly all dives I just swim through the eelgrass to get to deeper water. Yet Zostera  meadows are extremely productive. Eugene Kozloff's book Seashore Life of the Northern Pacific Coast devotes nine pages (320-328) to the flora and fauna of eelgrass meadows. In Arthur Kruckeberg's book The Natural History of Puget Sound Country, he quotes Ronald Phillips of SPU when discussing the productivity of eelgrass. In its capacity to produce biomass from sunlight and inorganic substances, eelgrass rates second to sugar cane and ahead of wheat, oats, corn and rice and is ahead of other natural ecosystems such as the tall grass prairies of Wyoming. I always see interesting flora and fauna on the way through so the last two dives I spent the entire time adding to my photographs of eelgrass communities. The following sampling just scratches the surface of what you can see on a dive in eelgrass.

Almost all blades of Zostera have egg masses of the tiny snail Lacuna variegata, the chink shell, and in some cases the snail itself.

Looking closely at some of those snail shells reveals small hermit crabs living in shells on a blade of eelgrass. Isopods can also be seen on eelgrass blades.

Other marine invertebrates living in eelgrass include the hooded nudibranch, Melibe leonina. This strange looking nudibranch is worth the price of admission on any dive.

Hooded nudibranch

Open wide for chow!

Nudibranch sex!

Melibe, the next generation (egg mass)

Another couple nudibranchs that can be seen on the blades of eelgrass are the opalescent nudibranch, Hermissenda crassicornis, and the orange-tipped nudibranch, Janulus fuscus.

Opalescent nudibranch

Orange-tipped nudibranch

Numerous crab species also call the eelgrass beds home. The following are just a sampling of what lives here.

Red rock crab

Decorator crab

Northern kelp crab

Helmet crab

Many of these crabs are on the menu of mink and otter that forage in the eelgrass, particularly the red rock crab and helmet crab.

Mink with a red rock crab

River otter with a helmet crab

Of course there are fish here too.  A sampling of those seen regularly are:

Penpoint gunnel

Crescent gunnel

Who's looking at me?

Another color variant of the crescent gunnel

Saddleback gunnel

Right-eyed flounder (English sole?)

White-spotted greenling stealing food from a red rock crab

Of course mink and otters like fish too! Everything from gunnels to flounders to great sculpins.

Mink bringing home a gunnel

River otter with a gunnel

And finally, the fish that prompted me to write this blog, the Pacific spiny lumpsucker. This tiny fish is many divers favorite. When I posted this photo on Facebook, it got the following comments:

"..without a doubt, my favorite local fish."

"cute little lumpsucker"

"JEALOUS!!!!"

"One of my favourite fish!!! You are so lucky. I'm still waiting to see my first one diving."

Pacific spiny lumpsucker