A Turtle and Three Trees

Hi Jane,

I enjoyed your lively letter.   I’m sure I would also have squeaked in delight at the unusual Darwinian experiments of a MALLARD diving instead of dabbling. Was she hungry?  Looking for diversion?

I happened to run into the City biologist, Gary Kittleson, last week, and he told me the important news that he had recently discovered a WESTERN POND TURTLE near the Branciforte outlet into the Lagoon.

Western Pond Turtle near Branciforte Outlet, August 2016 ,Photo by Gary Kittleson

This is the first SLR record of this native species in many years. The Western Pond Turtle is currently designated a Species of Special Concern, but is now being studied by the US Fish and Wildlife Service as a candidate for endangered species status. I thought it was a freshwater creature. I guess because of the sandbar, the water must be pretty fresh up to the Soquel Bridge where Branciforte comes in.

I’m happy to report that for the second time in three weeks, the City has been responsive to our concerns about habitat destruction on the River. More specifically, Public Works agreed to save three large native trees along the Riverwalk behind Keyser Arena. Gary has been the key to this small success.

Rescued Black Cottonwood at Entrance to Riverbend Native Garden

The story actually goes back a year. I was out on the river, checking on the grim cutting and chopping scene, when I heard the dreaded sound of chainsaws near an area behind the Keyser Arena. I dashed towards the area and discovered that the City was just about to cut down two beautiful large BLACK COTTONWOODS and a RED ALDER.

Second Saved Black Cottonwood

When I expressed my distress rather forcefully, stubbornly clutching the largest Cottonwood and saying I wasn’t going to move, the beleaguered foreman of the operation threatened (playfully) to throw me in the chipper. We both agreed that was not a good solution to our problem!  Instead, he called Public Works and Public Works called the City’s contracting biologist, Gary Kittleson. That was a great stroke of luck! Gary is an amazing fountain of information on both the biology and hydrology of the river as well as the construction history of the levee. As the biologist hired to consult at every step of the levee construction since 1999, he knows the details of every pump station, every gabion basket, every crib wall, every rebar, and, most importantly for our purposes, every detail of the required mitigation measures including all the restoration efforts that took place during the first five years of the Levee Project. After some conversation between Gary and a staff

Saved Red Alder

person from Public Works, the brush removal crew was ordered to allow the trees to stand! What luck that I had stumbled in blissful ignorance onto a designated restoration area, and that Gary happened to be available to go over that history with the City! Such is the course of human history – blundering and a little luck – plus some people like Gary who are highly informed.

 

I was not wrong in worrying again this year that the trees might be summarily removed. But once again, when I expressed my fear, Public Works met with Gary and was persuaded that the trees were part of the original mitigation plan and that they did not present a hydraulic threat to the levee. Public Works agreed that the trees could survive until such time as as the Army Corps rejected the reasoning of the biologist. I experienced a moment of real joy – seeing the trees standing tall, free to offer cover and food in their lovely branches for at least another year.

For the record, below is the technical rationale for saving the trees – provided by Gary to me in an e –mail. It explains why the trees will have no effect on the hydraulic model used by the Army Corps of Engineers to determine what vegetation can and cannot exist in the levee channel. I am including it here for future reference, not expecting most of our readers to read it.   Hydrology pretty much confounds me, but I keep trying! I hope I am never called upon to explain this to city officials.

The “model” is the numerical, hydraulic model that is run on a computer that simulates various flows through the levied reach of the river, based on annual cross sectional surveys that characterize the river from levee to levee.  The model tells us how high the water will be at a given flow and it considers the amount and size of vegetation, bed elevations, and water velocities, among other things.  This model is known as the USACE Hydrologic Engineering Center’s River Analysis System (HEC-RAS) hydraulic model.

The trees in question are far up the slope, in front of a massive structural wall designed to protect the road and Beach Hill, and they are probably above the 100 year flood level, because they appear to be in the top 3′ of the levee which is considered the “free-board” above the 100 year flood elevation.  The additional 3 feet of ‘freeboard” is crucial in terms of flood capacity and is required by the USACE and FEMA, as it provides some assurance that there will be maximum flood protection, with a bit of room for the flood to splash around, rather than breaching over the levee top.

I have a dream that I will help create a native plant restoration project there called Riverbend Native Garden.  I have already talked to Public Works about once again designating this patch of land behind the Arena as an officially marked restoration area. I learned that the history is not promising! Once the Army Corps was no longer in charge of planting and protecting the area, the area was slowly taken over by illegal activity and many of the plants were destroyed.  The miracle is that in addition to the three native trees that we saved, there are many other native plants that have refused to give up – including COYOTE BUSH, HUCKLEBERRY, WILD ROSE, BOX ELDER, COFFEEBERRY, WILLOW, MUGWORT, NATIVE BLACKBERRY and YARROW, all planted as part of the restoration requirement.  What is really required now is to simply protect the area and allow natural recruitment to take place. As you and I are always saying to the City,  signage would help a lot!  Public Works has agreed to work with me in at least the first stages. Right now they are trying to find the original Army Corps of Engineers’ plan for the area, with the list of plants that were added. I am hoping I can find someone to work on this with me. Any takers out there?

Entrance to proposed Riverbend Native Garden.  Large cottonwood on left.

Looking downstream from Riverbend Garden towards Riverside Bridge.  This is the more degraded end of the proposed Garden.    ARROYO WILLOWS AND COYOTE BUSH dominate.

 

Looking Upstream from Riverbend Garden towards Laurel Bridge, TULES and COYOTE BUSH are dominant.

I have been reading Rachel Carson’s biography. What a story! She was one of the first to help large numbers of  people  really grasp the difference between an anthropocentric view of nature and a biocentric view. My experience unfortunately makes me think that about 10% of our Santa Cruz community has truly adopted this latter perspective. I’ve only really internalized it myself in the last two years while working on this river blog with you. We’re so slow to catch up with our prophets.

Keep on diving and dabbling,

Barbara