Crissy Field Exploration

1a. Starting down the path at Crissy Field

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- Across the street from Crissy Field center, a wide path invites visitors to venture into the park's dunes and marshes.

1b. Sign along path

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- At the entrance to a path that crosses Crissy Field marsh, a sign reminds visitors they're in a delicately restored area that needs to be treated with care.

1c. Saltwater marsh

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- Birds frequent this area, which looks much like a lagoon but is technically a saltwater marsh. You'll usually find ducks, gulls, and other waterfowl congregating.

1d. Bridge across salt water marsh

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- A bridge spanning the marsh offers better views of birds and other animals.

2a. Great egret, Crissy Field

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- Whether in the marsh or along the dunes, you're likely to come across some majestic and sizable waterfowl during a walk at Crissy Field. This great egret, one of the larger members of the heron family, was spotted alongside the marsh waters.

2b. The great egret's characteristic coloring

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- The great egret's signature costume is a yellow bill and long black legs, as opposed to its cousin, the snowy egret, which sports the opposite color combination. Great egrets, found on all continents except Antarctica, average about 40 inches in height with wingspans of up to 57 inches.

2c. Snowy egret, Crissy Field

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- The snowy egret also populates Crissy Field marsh. You can distinguish it from its larger cousin, the great egret, by its black bill and yellow feet. The snowy egret is also considerably smaller, standing about 2 feet tall.

2d. Brown pelican, Crissy Field marsh

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- Brown pelicans, with wingspans of up to 8 feet, are frequent visitors to Crissy Field, and can often be seen skimming the open waters of the Golden Gate. In the 1970s, research on the negative effects of DDT on brown pelican eggs helped get the pesticide banned.

2e. Brown pelican flapping

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- Occasionally, the pelicans will repeatedly slap their wings against the water, splashing around. It's not entirely clear what drives this behavior, but they may be scavenging for food near the surface of the water.

2f. Brown pelican flapping

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- More flapping.

3a. Looking down from the bridge

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- From the bridge, glance down at the muddy sand below and you'll see a field of holes that take several different shapes. Critters like ghost shrimp, clams, and polychate worms make their homes by burrowing into these sands.

3b. Long view of marsh mud

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- The appearance of mud in the salt marsh changes with the tides. The tide was out when this photos was taken, revealing burrows of small marine animals.

4a. Scrubby dune habitat

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- Turn right at the end of the bridge, walk a short ways, and you'll find yourself sandwiched between two different habitats. On your right, a scrubby dune is covered with low-lying bushes and other plants that enjoy a drier, sandy soils.

4b. Chamisso Bush Lupin foliage

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- Chamisso Bush Lupin is a common find on the dunes. In the spring, Chamisso Bush Lupin produces violet flowers. It is named after french naturalist Adelbert von Chamisso, who also named the California poppy during an exploratory voyage to North America in the 1820s.

4c. Chamisso Bush Lupin in fall color

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- This dried specimen of Chamisso Bush Lupin shows the plant's seed pods, which rustle and make noise as the shrub shakes in the wind. In the spring, Chamisso Bush Lupin produces violet flowers. It is named after french naturalist Adelbert von Chamisso, who also named the California poppy during an exploratory voyage to North America in the 1820s.

4d. Chamisso Bush Lupin

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- A closer look at the lupine's twisted seed pods.

4e. Indian Paintbrush

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- These Indian paintbrush plants, still in bloom in late fall, enjoy the sandy soils of Crissy Field's dunes. Indian paintbrushes are semi-parasites. It's also worth noting that they're pollinated by hovering birds and insects, as their leaves and flowers offer no real parking place for potential pollinators.

4f. Indian paintbrush flower

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- Getting up close to the Indian paintbrush flower.

4g. Indian paintbrush flower

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- And closer still.

5a. Dune swail

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- On the left is a habitat called dune swail. This patch is now the only example of a habitat, characterized by tall grasses, short trees, and occasional cattails, that was once common in San Francisco. And we're fortunate it's here: not included in the original Crissy Field plan, the dune swail was added to address other needs that arose in the area's restoration.

5b. Dune swail reeds and sedges

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- Reeds and sedges like these, found in the dune swail environment, were used by native people of the region. Native Americans are allowed to collect these plants for cultural purposes if they choose to.

5c. Tree in dune swail

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- The dune swail is the only freshwater habitat along this walk, and supports a variety of trees. From here you can see the dome of the Palace of Fine Arts, where the Exploratorium is located.

5d. Leaves on tree in dune swail

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- Trees in the dune swail habitat grow larger leaves than do the shrubs growing across the path, out of reach of the supply of fresh water.

5e. Wasp gall

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- Parasitic wasps and midges use the undersides of leaves on trees in the dune swail to lay their eggs. These egg packages, called galls, are often brightly colored and can take some interesting shapes.

6a. View from second bridge

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- Closer to the beach, a rocky inlet provides hunting and hiding grounds for lots of critters. Here, another egret tiptoes its way around, searching for a morsel.

6b. Snowy egret (Egretta thula)

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- A closer view of a snowy egret. You can identify it by its black beak and yellow legs, the opposite color scheme of its cousin, the great egret.

6c. Top smelt jumping

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- Keep an eye on the surface of the marsh's water and you might see the silvery flash of a topsmelt leaping. These fish get their name by their habit of swimming near the water's surface. Topsmelt aren't actually true smelt, they're members of the silversides family. That relation is apt: it's their silvery scales that make them glint so brightly as they leap.

7a. Two-sided dune

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- Rounding a dune near the beach, you can see evidence of the wind's effects on plant life. Low-lying shrubs and other plants cover the more sheltered side (on the left in this picture) like a rugged carpet, while the windy side boasts mostly sparse bunches of American dune grass interspersed with hearty wildflowers.

7b. Beach strawberry

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- The native beach strawberry spreads runners throughout the less windy side of the dunes, taking over large patches. These runners not only serve as the plant's main form of reproduction, but they also help retain the dune's sands. In the spring, they bloom with small white flowers that later produce scarlet berries similar to our more familiar strawberries.

7c. Marsh gum plant

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- The marsh gumplant takes well to salty soils. The native Ohlone used the plant's signature sticky sap as a balm. The scent of the leaves, if you crush them between your fingers, is reminiscent of fruity candy.

8a. Dune grass

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- On the windward side of the dune, dune grass helps to anchor shifting sands and retain the dune's shape. Dune grass grows from stems that spread underground, an ingenious adaptation that keeps the plant from being buried by windblown sand.

8b. One post, two post, old post, new post

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- The constantly shifting dune landscape at Crissy Field beach means a fence that surrounded a dune a month ago might no longer be on the dune's edge. Rangers frequently put new fences in front of old ones in an ongoing effort to protect the dunes from dogs and people.

8c. Native and non, side by side

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- Crissy Field's dunes are populated by both indigenous and non-native plant species. Here, the plant on the left, with the tiny white flowers, is a a visitor: Cakile maritima, commonly known as sea rocket. The purple flowers belong to the native Abronia umbellata, also known as pink sand verbena.

8d. More and different verbena

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- This lovely yellow-flowered plant is frequently found in along the windy side of the dunes. it's Abronia latifollia, or yellow sand verbena.

9a. Crissy Field beach

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- Looking west along the beach, you can follow the flow of water as it winds its way inland to the salt marsh. On its way, it carves an ever-changing channel. The not-so-distant Golden Gate bridge adds to the scenery.

9b. Sandbar and water inlet

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- A walk along the beach brings you to the inlet of the salt marsh. Depending on the tides, you may have to wade through some shallow water or walk inland a bit to navigate around the marsh.

9c. Killdeer on sandbar

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- A killdeer pokes around a sand "island" in the inlet.

9d. Kildeer closeup

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- A closer view of a kildeer. These successful shorebirds are often seen at Crissy Field, and tend to adapt well to habitats modified by humans. Listen for their call: "kill-dee, kill-dee." Photo by: hart_curt

9e. Marsh inlet

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- A narrow inlet on the beach lets bay water flow in, creating the salt water marsh. Waves constantly pile and shift sand along the sandbar, sometimes closing the inlet, which rangers must regularly dredge to reopen.

10a. Four legged friends

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- Crissy Field beach is a favorite for folks out walking their dogs. You'll often see many four-legged friends digging together in the sand or swimming for frisbees in the waves.

10b. Happy feet

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- Signs of a day at the beach.

10c. Sights and Sounds of Crissy Field

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- The sounds of Crissy Field are not to be missed.

path

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