The Mud Cracks of Coyote Hills

//The Mud Cracks of Coyote Hills

The Mud Cracks of Coyote Hills

Coyote Hills Regional Park – East Bay Parks – Fremont, California
Coyote Hills Regional Park – Trail Map (pdf)

The Mud Cracks of Coyote Hills could be a family of mutants, living under the floor boards. But they’re not. They should be. This would be a better post.

These mud cracks are the images you see of the playa, of evaporated salt flats, of terrain expressing desolation. And here, the mud cracks are emblematic of seasons that cycle from lush and winter blue . . .

Coyote Hills After Winter Rains

Coyote Hills After Winter Rains - ©ingridtaylar

. . . to scorched and thirsty after heat and sun sear the mud.

Coyote Hills in Late August

Coyote Hills in Late August - ©ingridtaylar

I took a sunset walk at Coyote Hills Regional Park, and seeing the marsh still soaked with water in July, I was reminded that I had this archive of mud crack photos. I’m not sure how you forget that, but I did. They were taken in August of last year, after a long, hot summer.

Another before and after . . .

Coyote Hills Marsh After Rains

Coyote Hills Marsh After Rains - ©ingridtaylar

Coyote Hills Marsh in Drought

Coyote Hills Marsh in Drought - ©ingridtaylar

The lines and ridges start to form in the marsh as the water recedes and evaporates. The formerly saturated mud dries out and shrinks into this fabric of polygons.

Mud Cracks in the Marsh

Mud Cracks in the Marsh

Mud cracks are actually useful in ancient sediment studies. They can help determine the original environments of fossils, suggesting areas like playas and shallow basins where water evaporation could have occurred. That is, of course, a simplistic description of mud’s academic value. I can’t get into the complexity.

Coyote Hills Marsh in Summer

Coyote Hills Marsh in Summer

For the purposes of this post, mud cracks provide these outstanding textures and colors . . . even if I couldn’t help but wish for winter rains to ease the discomfort of this drought-time imagery.

Dried Mud in the Marsh

Dried Mud in the Marsh - ©ingridtaylar

The Color of Evaporation - ©ingridtaylar

The Color of Evaporation - ©ingridtaylar

[Temporarily] Lost Slough

Temporarily Lost Slough

By | 2009-07-21T15:03:05+00:00 July 21st, 2009|Blog, California, Environmental Issues, Issues, SF Bay Area, Weather|3 Comments


  1. Dr. Johanna van de Woestijne April 7, 2013 at 6:38 pm

    To a certain extent the water flow into the sloughs is controlled. I believe that the cracks in August are only partly due to low rain, as the park management was also trying to control invasive species of marsh plants. Apparently the native tule does better relatively if there is more drying out in the summer. The tule are considered more desirable as nutritious food source for wildlife, versus the pampas and other invasive marsh plants. So, the cracks may have been part of a management decision, as I remember it. The photos are a nice reminder of how very shallow those marshes really are.

  2. ingrid April 7, 2013 at 7:14 pm

    Thank you, Johanna. I should have been more careful in my description of the images as “drought,” you’re absolutely right. At the end of every summer I craved the return of the rains, hence the associations. I appreciate the additional information, too. I don’t know if you’ve been to Coyote Hills in the summer when the carp slither through the shallows. As invasive species, I know they’re rarely welcomed and I wondered if they were still there. I also haven’t heard any updates on the Patterson Ranch development to the east of Coyote Hills which was so ardently opposed by local citizens. I know water and flood-plain issues were among the contentious ones there.

  3. Dr. Johanna van de Woestijne April 7, 2013 at 7:37 pm

    I never go there after June, because it is too hot. As to development, I believe all is still under contention, including an amusement park with overnight camping for fees in the old dairy barn area. I can check on the status of that. About the carp, I had a very good laugh trying to photograph Turkey Vultures picking up the carp last fall, from muddy shallow marsh waters. You would normally say that Turkey Vultures don’t hunt and can’t do what I was seeing them do, in pursuit of stranded carp. It looked like the TV were fishing, but you had to know the water was only about four inches deep. I think the carp are still there, but I think the Turkey Vultures are enjoying the moment in late summer and early fall. I surely enjoyed the moment of watching Turkey Vultures “fishing” successfully in the shallow marshes at Coyote Hills. Wish I had taken video, because it was a special moment.

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