Crabs in the lower Russian River

Not known to a lot of people, there are a lot of crabs that come into the Russian River during the summer months. Dungeness crabs. Sometimes there’s hundreds, sometimes thousands, such as last year and sometimes not too many, such as this year. You usually don’t see them, hardly even a shell along the shore line, but, watch the critters eating them and you’ll know they are there.

What eats the crabs?

Likely just about everything down there eats the crabs. Most of the crabs are very small, about two inches but there are larger ones also.I first noticed them when I saw seagulls diving for them and eating them during the evening. I can pretty much tell about how many there are by how many seagulls are eating them. I’ve also seen the otters eat them, lots of them, they go down, come up to eat it and go down again and again. They eat a lot. Now, I think the seals likely eat them too, but they can eat underwater, so I’ve never seen one eat them. I’m sure a large fish can eat some of the little guys that are about two inches across, but haven’t seen that ether as it all happens underwater.

The question, do the crab benefit the fish that the Biologists are trying to restore?

That’s a good question. At first, I was under the impression that, not much, maybe the larger fish can eat some of he smaller ones, but most are too big for the smaller smelt to eat, so it doesn’t seem like they are that great of a food source.

However, after watching things eat these little morsels for four years now, I’ve changed my mind on that one. When a seagull try’s to eat one of them, other gulls fight over them and they get broken up while eating, a lot of little crab pieces are created during this process. In other words, the eating process of crabs creates a lot of little pieces for other little creatures to eat.

When an otter gets one, he brings it to the surface to eat it as otters can’t eat underwater as seals do. They usually crunch the body section on larger crabs and let the legs and claws go as they are well armored and it’s easier for them to just go get another crab instead of messing with these hard pieces. They crunch the little ones too, little pieces flying everywhere.

Now, I’m sure the seals eat them too, or they should, but I can’t see. Should be more little pieces from this operation too and I’m sure there are other creatures down there eating them too, breaking them up into little pieces. Yummy.

Thousands of little pieces mean lots of food.

So, after watching this action, I changed my mind and do indeed think these crabs provide a lot of food for a lot of things. Lots of little pieces of crab eaten by little things that the fish eat and little pieces for the fish to eat also. Small crabs for the larger fish to eat.


Biologists using nets to sample fish population.


An otter, was diving for crab.


More crab eaters.


Dead Crab. Fish food?


An otter has a nice big one, about half legal catch size.


Note the pieces on the shore line.


Yum, Yum.


They usually eat the body and leave the legs and claws as they are too well armored.


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