Under the Rock: Pea Crabs at Crab Cove

Place: Crab Cove Regional Park, Alameda, California
Visit dates: May 5th, 10th and 12th, 2012
Difficulty: very easy

During my 12 years in the Bay Area, I've been to Alameda only 4 pr 5 times. This sleepy island town has always been out of the way for me and, not having friends or family or any other business there, the sole reason for my visits have always been just one - Crab Cove Regional Park.

Mud flats exposed

 This park is very small. It is not the place for a serious, strenuous hike. It is, however, perfectly suited for an easy family stroll. Add to that a visit to the visitor center, a picnic outside, and a fun time at the beach (which during season can also include bay swimming) and you have a perfect family day.
On weekends, parking could be a challenge. But even when the place is full of people, there is still a lot of Nature to see and observe.

On May 5th I went there by myself to prepare for a school field trip of the little chika's kindergarten class. The tide was low and I began my exploration by turning over wet driftwood and rocks at the beach and the exposed mud flats.
Wet driftwood is the perfect hiding place for sand hoppers - tiny crustaceans who dwell in the sand just above the strandline and feed on rotting seaweed deposited by the tide. Unfortunately they were too quick for me to photograph. Shore birds are much quicker. though. They need to be, because they feed on these tiny critters.
The pea crabs, however, were a different matter. They hide under the rocks and quickly dig themselves in the wet sand when exposed. During the field trip the children were completely fascinated by them. One crab sat still long enough for me to photograph it.

A pea crab

On the north side of the park there is a paved trail that is walkable only during low tide. It was exposed just enough for me to walk on it without getting my feet wet.
I then continued north to the remains of the old wind-breaker, observing the birds. There were quite a few ducks and grebes floating lazily on the calm water. Next to the rocks there were may crab molts. I hopped on the rocks to get a closer look but before long I had to back track because the tide was already coming in.

A pair of greater scaup cruising the bay

A great egret on the shore

Sleepy gulls

A horned grebe

 Going back south the trail that goes below the strandline was already too flooded for me to walk so I walked on the high trail, continuing to the little fresh water pond at the south part of the park, bordering Brawn Regional Beach.

Canada geese in the pond

 There is a trail that encircles the pond and a little observation deck. On the way to the pond I met a family of Canada geese, a pair with five goslings. One of them (Papa Goose, I assume) was particularly aggressive and took on anyone who came even remotely close. He even hissed at a mean-looking pit bull that seemed eager to accept the challenge but was hurriedly pulled away by the human at the other end of the leash. A few minutes later, that very same goose was chasing away all the other waterfowl away from the pond, securing a private swim-time for his family.

A Canada goose family going for a walk:

They weren't the only family there. 

Mamma mallard with her ducklings

A week later, when I escorted the kindergarten class on their field trip we saw four goose families with chicks and despite the place being crowded with children, all geese seemed tranquil and at ease.
The pond, on all three occasions, was teeming with bird life. Great and snowy egrets stood erect in ambush by the cattails, their long, white necks standing out amongst the green stems. Red-wing blackbirds chirped in the vegetation and s number of coots and mallards meandered along the shore. A single cormorant patrolled the pond back and forth, occasionally disappearing under water.

Snowy egret

Double-crested cormorant

I saw turtles sleeping on a log, undisturbed by the birds.

I circled the pond and returned to the visitor center along the shore, where I scared off a flock of gulls and noticed a pelican on the concrete barrier that extends into the bay.

The visitor center is small, but has a rich and charming exhibition of bay life and quite a few books, toys and activity kits for sale. They also have adventure backpacks for loan, with exploring activities and equipment for nature explorers of all ages.

I enjoyed Crab Cove so much that on Saturday, May 10th I arranged for all the quail family to go there for a Nature stroll and a picnic. Papa quail took his long lens camera and photographed the birds, which where all over the place, even though the park was jam-packed with people. 

The Kindergarten field trip was scheduled to a time of low tide. Much lower than the time I was there by myself.

Mud flats exposed during low tide.

Under the film of water that covered the mud flats we saw little 'volcanoes' where in their 'craters' appeared tiny tentacles swishing the water at a great speed. These tentacles were quick to disappear when we approached.

The children had a wonderful time exploring the mud life.

An unfortunate snail

I greatly enjoyed all three visits to crab cove. By myself, with my family and with the kinder class. It is a wonderful place for a Nature getaway without getting too far away.