The Watch Newsletter of the Watsonville Wetlands Watch Spring 2004

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Slough Niche: Why Duck Populations Change

___On February 13, 1976, biologist Randy Morgan strolled out to the overlook at West Struve Slough and counted 300+ pintail and 250 cinnamon teal swimming about among the stems of curly dock, bulrushes and smartweeds. Five years later, he counted 300 cinnamon teal at the same spot, and estimated the total number in West Struve, Hansen and Harkins sloughs at more than a thousand.
___Two years after that, on February 10th, the bird club counted 130 cinnies at the overlook; on January 7th, we counted 202 pintails in Harkins Slough and 111 in lower Hanson.
___Admittedly, these are peak numbers. Yet, from 1975 through 1984, it was rare to encounter fewer than 50 cinnamon teal on any given visit to the three branches. They always seemed to be out there, the dark bodies of the males always striking against the bright water of the sloughs. Perhaps this is why, at first, the declines in cinnies and pintail weren’t really noticed, or much concern. As recently as 1994, I observed 77 pintail in upper Harkins.
___In recent years, though, cinnamon teal and pintail have become much less common. Many winter visits to the sloughs transpire without a sighting of either species. Shoveler, conversely, have increased. From seeing only a few scattered individuals per trip during the 70s and 80s, now it isn’t unusual to see 50 or a hundred. So, what has changed?
___There may be regional population trends at work: cinnamon teal numbers are down in certain other locations in the Monterey Bay area. But local factors also may be at work.
___In the 60s, the sloughs were heavily grazed and cultivated. Lower Harkins was a big cornfield; the upper slough was in cauliflower, squash and other row crops. Like the Chinese potato farmers a hundred years earlier, truck farmers found the rich peats of the sloughs an ideal environment for producing vegetables as long as the soil didn’t get too soggy.
___Struve Slough was grazed by cattle - grazed bare, right down to the peat chalk.In the late 60s and early 70s, increasingly wet conditions gradually forced farmers out of the slough bottoms. As the wetlands recovered, earlier successional stages showed a great diversity of wetland plants favored by waterfowl. Along with curly dock and smartweed, there was a lot of spike rush, sedge, bulrush and fat hen, even some Japanese millet.
___As the years passed, though, a series of sediment disasters affected both branches of Struve. In the West branch, topsoil eroded from expanded strawberry fields on the terrace slopes north of Harkins Slough road - a short-lived experiment from which the soil and associated grassland will take decades to recover. Topsoil from this insult fanned into the lower slough, where it smothered native species and fostered rank growths of cocklebur, ox-tongue, and, later, cattails.
___In Hansen Slough, a reverse process took place. Hansen Slough became very attractive to waterfowl in the mid-80s after a farmer, planning to mine his peat, cut down the willow forest in lower Hansen. Nutrient rich runoff from the feedlot upstream probably encouraged high invertebrate populations of annelid worms, nematodes and aquatic insect larvae that are heavily consumed by waterfowl in preparation for reproduction. But a well-intentioned and fairly effective restoration project in the early 90s established a series of check dams in the upper slough that blocked sediment and nutrient movement down the slough, possibly affecting invertebrate populations. Large numbers of waterfowl now feed above the check dams, but these are mostly mallards and green-winged teal.
___A similar devolution unfolded in the main branch of Struve, where flocks of ducks and large numbers (100+) of snipe once foraged below a buffalo wallow in a swale that was later occupied by the Target store. The loss of this manure source, coupled with a series of sedimentation events stemming from the massive winter grading activity permitted by the City of Watsonville, and the increasing overgrowth of smartweeds in this branch, may be causes of the rarity of cinnamon teal and pintail now.
___The now-abundant shovelers, conversely, are surface feeders that may have benefited from the apparent ground subsidence in the sloughs and greater areas of open water.
___Hundreds of ring-necked duck, a diver that frequents shallow systems just beyond the reach of tipping ducks, now also reside in the sloughs in winter, possibly reflecting deeper water in some locations.
___So it was with some excitement that I focused my binoculars on a group of eight pintail and six cinnamon teal in lower Harkins Slough recently. They were gathered along the shoals of a large sediment fan formed at the base of eroding lettuce fields.
___It was a clear, beautiful and cold afternoon with lots of wildlife activity. A resplendent male red-shouldered hawk soared overhead. A kingfisher landed on a high snag to rattle and show off its white turtleneck. A Cooper’s hawk zoomed into a willow copse. Up on the hillside, a white-tailed kite perched delicately on low-growing plant stalks. The pintails bathed at length in the chilly water, loudly splashing water over their backs, then shaking their wings and puffing their feathers. After thoroughly bathing, they commenced tipping to feed, long tail feathers stabbing the sky.
___With their dapper design of brown, gray and black pinstripe, spotless white fronts and black-lined beaks, pintail are the among the most elegant of the waterfowl - aristocrats in Armani suits. With their long necks and watchful habits, they are very hard to approach and great fun to sneak up on. In coming years they will provide a litmus test for the sloughs, a measure of our success or failure in promoting conservation and habitat restoration in these treasured wetlands.___- Jerry Busch

What's News

New Brochure
Many thanks to Kay Metz for making possible the new, full color, English/Spanish brochure describing our organization. She and Lisa Zaretsky worked together on the design and Lisa’s husband, Paul Zaretsky, donated his lovely photo of the Great Blue Heron for the cover.
If you need brochures for an event call Carol Whitehill, 728-5667.


New fundraising campaign
___You may already have received our first fundraising letter.
The good news is that interest in the Watsonville Wetlands is increasing rapidly. We are involved in several restoration and mitigation improvement projects, and expanding our educational efforts among both children and adult community members.
___Our 12 years of work is paying off! The only problem is that interest in our work is outgrowing our means!
___To help us address this challenge, a generous member will double the first ten $100 donations this year. This is a wonderful opportunity for you to increase your investment in the Watsonville Wetland Watch. Your membership renewal in any amount will help us to continue to meet this tide of interest with good long term stewardship of our unique fresh water wetlands.

New docent class
___The first docent class of the Watsonville Wetlands Watch started early this year to learn about the Watsonville wetlands in order to 'spread the word' in many ways. After our charter docents learn how the wetlands are important to the overall health of the Pajaro Valley, learn the rich cultural and geological history of the sloughs and learn how to interpret nature for people of all ages, they will be ready to participate in many exciting and fun activities in the sloughs.
___Docents will have a variety of ways to support our efforts. Over the past year more than 1,000 school children have visited the Watsonville Wetlands for the first time; docents will help them discover the muddy marvels here. We areinvolved in restoration along the sloughs and docents can help lead these efforts. The City of Watsonville is building 6 miles of trails rimming the sloughs; docents will lead birding tours of the sloughs and introduce folks to the beauties in their marshlands. The new Pajaro Valley High School will include a Wetland Resource and Education Center (WERC) which is a joint project of the PVUSD, the City of Watsonville and the WWW; docents will be vital to the running of the WERC.
___As you can see, public interest and awareness of our sloughs is increasing rapidly. This dedicated group of citizens will be instrumental in bringing awareness and appreciation to this often overlooked treasure.
___Marian Martinez and Bob Culbertson, each with many years of experience in education and interpretation, have developed an excellent program to train this core of charter docents.

Red-legged Frogs: Living on the Fringe
___Adjacent to Harkins Slough Road where it crosses the slough just west of Highway One sits a small pool under a willow tree. The willow’s gnarled boughs rise out of dark waters to drop scattered leaves and catkins on the pond’s surface; an old tire disgraces the shallows near the road. It is not the first place one would look for a threatened species.
___Yet this unassuming pond is one of the last redoubts of the California red-legged frog in the Watsonville Slough system. The frogs hide in nooks and crannies of the stone retaining wall by the road or hop into the road culvert itself. Hemlock stalks, the willow, cattails and other brushy plants provide thick cover around the pond’s banks. Ground squirrel colonies in nearby uplands provide summer refugia for the frogs.
___The red-leggeds persist here despite the presence of their archenemies, the bullfrogs, a non-native, invasive and voracious cousin with a taste for red-legged juveniles. The big, bad bullfrog was brought to California from the Mississippi basin by frog-leg enthusiasts disappointed with the thigh-width of the indigenous fare.
___Pursued by bullfrogs, crayfish and other predators, disturbed and contaminated by urban development and habitat loss, red-legged frogs now are seldom seen around the sloughs. A survey turned up one adult and one juvenile near the new Sea View development. Two others were discovered during the 90s in stock ponds near the lower end of Harkins Slough. The species was observed in the slough ditch of middle Watsonville Slough, and in the old peat ponds at Hansen Slough. No one really knows whether these other populations still exist.
___We do know this: the last documented RLF population center in Watsonville Slough will be wiped out by a new bridge serving the new high school just beyond the slough. The bridge is needed to safely transport students across the slough, as the current road is narrow and dangerous. ___Construction of the bridge will result in destruction of the pond, the berm and the culvert.
Although the county investigated leaving the berm, culvert and pool in place during the bridge construction, it was precluded from doing so by the coastal plan for the new high school. The Coastal Commission, when it reluctantly approved the high school, required a number of measures to protect the sloughs and grasslands surrounding the site. One of these was removal of the berm and culvert that generated the frog pond, to improve “connectivity” above and below Harkins Slough Road.
___The Coastal Commission’s measure was well-intentioned but ill-conceived, drafted without a thorough understanding of West Struve slough or its processes. Far from damaging the slough system, the road berm performs the beneficial function of reducing the amount of sediment from development and agriculture in the watershed that reaches sensitive marshlands downstream. By blocking sediment, the berm also reduces the influx of pollutants stuck to the sediment particles. And the water that passes through the culvert and falls to the slough on the other side scours out the pool where the red-legged frogs survive.
___Because the red-legged frog is a federally threatened species, the U.S. Fish and Wildlife Service issued a “biological opinion” on the potential effects of the bridge project. The service determined that because the pond is small and somewhat degraded, and because red-legged frogs have been recorded elsewhere in the slough system, destruction of the pond did not place at risk the “continued existence” of red-legged frogs in the sloughs.
___In approving the county’s incidental “take” of the frogs, the service required no substantive mitigation measures. The preparer, Bill McIver, and his supervisor required only that the county remove any red-legged frogs or frog predators from the construction site before starting work, and control weeds and water during the project.
___McIver did recommend modest measures, including monitoring of the red-legged frog population at the project site, a long-term county management plan to conserve endangered amphibians and a three-year predator removal program at the site. But county staff and the EIR excluded even these minimal proposals from the recommended mitigation plan for the project. As to the measures needed to mitigate the permanent loss of red-legged frog habitat, the EIR provided a two-word answer: “none required.”
___Any herpetologist familiar with the sloughs will tell you that the population status of the red-legged frog in Watsonville Slough isn’t known. It is possible that the frogs might have several subpopulations in the Watsonville Slough system and it is possible that they might not. If they do not, and the little pool by Harkins Slough Road is the species’ population center for the sloughs, the EIR is at risk of invalidation for not disclosing a potential significant impact of the bridge project: namely, the extirpation of red-legged frog from Watsonville Slough. And the biological opinion is at risk of challenge for failing to require a Habitat Conservation Plan for the taking of red-legged frogs.
___The county could implement several alternatives to reduce the impacts on the frog. The supervisors could move the bridge 20 feet to the north and conserve the pond. They could keep the bridge where it is and conserve the pond, and ask the City of Watsonville and the Coastal Commission to modify the condition requiring the road berm to be removed. They could do a frog census and prepare an RLF management plan for the slough system, with additional mitigation measures such as removing bullfrogs and crayfish from any new RLF loci. They could construct an off channel replacement pond nearby. They will make none of these changes unless WWW can convince or force them.
___At this time of year, red-legged frogs are singing their mating song, an abbreviated “thonk” that sounds like a child hitting the bottom of a plastic bucket. How ironic and sad it would be if this rare noise, like the last south county population of burrowing owls (evicted to build the high school parking lot), was silenced by the first high school in the Monterey Bay area to inaugurate a core curriculum of “Wetland Science” and teach all its students the importance of environmental stewardship!

Winter Restoration Work In the Sloughs
___The steady rains and the short days of winter are a time for most of us humans to slow down and replenish our energies. For the plants out in the Watsonville sloughs and for many plants in California the winter rains signal a time of waking up from summer dormancy, a time of growth and abundance. A walk out in the Watsonville sloughs during the winter reveals much more than abounding water. If you look closely you will see the flat, red tipped leaves of the brown-headed rush creating magical mounded nests throughout the wetter parts of the uplands. The California bunch grasses such as California Oat grass and Purple needle grass are greening up and towering above the annual grasses that usually shade them out by late spring. Annual wildflower seeds such as the vibrant sun cups and the endangered Santa Cruz tar plant are germinating, setting down roots and putting on the green leaves that will sustain them through the dry months to come.
___The steady rains of winter have also signaled the time for planting. Starting at the end of November until this last week of January, the Watsonville Wetlands Watch restoration committee along with a huge crew of students and caring community members has planted a total of 4,200 Coastal prairie grasses, sedges and rushes into areas where invasive species of Poison hemlock, Harding grass and Italian fennel once dominated. This winter planting marks another stepping stone in our process of restoring native plant biodiversity to the Ecological Reserve on West Struve Slough. The plants were all grown from seed that we carefully collected from the small stands of native grasses, sedges and rushes that still thrive in the Watsonville Slough System. The plants were tended with deep care by Tom Schroeder of Native Oak Nursery and by the students at Amesti school. The areas where the plants were planted were once weed infested , but have been controlled by our three years of tenacious weed removal methods.
___We would like to extend a warm thank you to all of the folks who helped make this planting such a success. We thank the enthusiastic fifth grade classes from Amesti elementary school who have helped us in all of the aspects of restoring the Watsonville Wetlands. They have collected seed, studied about the plants and animals of the wetlands, grown 1,000 native plants in their greenhouse and planted them back out at the wetland. We thank the students from Linscott Charter school who have been able to witness the rushes that they planted last year thrive and grow and who will see their new colonies of rushes take hold in the years to come. We thank Calabasas elementary school and New School for helping us replant California bunch grasses, sedges and rushes in a large area that had once been dominated by poison hemlock. Finally a huge thank you goes out to the hearty crew of volunteers including the KEY club at Watsonville High school who have come out rain or shine on Saturdays to lend a hand in returning native grasses and wildflowers back to the plots where Harding grass once grew.
___As the rains continue to fall, I pass on blessings that the newly planted grasses, sedges and rushes sinking their tender roots into new soil may grow to be vibrant and healthy. I hope that the day will come when we won't need to bring our shovels out to the slough for planting. I hope that the day will come when the California oat grass, Hayfield tarweed, bright yellow sun cups and fuzzy morning glory will only need the birds, wind and other forces of nature to plant them and keep this threatened ecosystem in balance. ___ - Laura Kummerer

Fighting to Save the River
___The Army Corps of Engineers and the two counties that share the Pajaro River (Monterey and Santa Cruz) are pressing ahead with plans for a drastic remake of the river channel. Monterey County is also pressing for permits for an interim maintenance plan that would clear and mow most of the channel vegetation, virtually destroying all of the habitat for wildlife.
___Our hopes for a better project and a "Living River" are resting on a local group sponsored by Action Pajaro Valley and on the Regulatory Agencies that will have to approve permits for the project. However, the Counties are justifiably concerned about their liability for past and future flood damage and are desperate to find a solution. The Army Corps has a favored alternative design that does not meet many of our objectives. The Counties are scheduled to adopt a Locally Preferred Alternative in February or March.
___Action Pajaro Valley's Pajaro River Task Force is a group of approximately 24 people representing the various interests in the River. The Task Force has been meeting on a regular basis for over a year trying to find a solution for the River problem. The Task force's objectives include flood protection, preservation of farm land, reduced construction and annual maintenance costs, and saving riparian habitat. The group hopes to negotiate a mutually acceptable solution to present to the Counties and the community. The present challenge is to convince the Army Corps and the Counties to incorporate the Task Force's design as the Preferred Alternative.
___It is unknown at this time if the Task Force can agree on a mutually acceptable design or if the Army and the Counties will consider it. This is an ongoing critical issue for the Pajaro Valley and Watsonville Wetlands Watch. Stay tuned. ______-Jim Van Houten

ISO LAWYER, for LTR
Can anybody recommend a Lawyer who would be willing to develop a relationship with WWW and help us with our many and varied education, conservation and restoration projects? We aren't looking for free legal service (though we'd take it if we could get it). What we would like is an advisor, someone that could become familiar with us and our projects, advise us on routine issues, and provide more intensive (paid) legal services (either directly or indirectly) when needed. Anyone with suggestions or information should call Jim Van Houten (684-1861) or Kay Metz (423-2545).

Join Watsonville Wetlands Watch . . .
and help protect our wetlands! Membership of $25 a year/$15 student or senior, supports efforts to preserve and protect slough systems in the Pajaro Valley. You'll also receive our newsletter, The Watch. Visit our Membership page for more information.
. . . and thanks to a challenge donor . . .
your donation of $100 will be matched by a generous supporter! This is your opportunity to make your contribution count double!

Check our Calendar for Habitat Restoration Dates and Times
General Meeting - Feb. 23 ~ 7:30 pm at Pajaro Valley Arts Gallery, 37 Sudden Street, Watsonville
Field Trip to Pajaro River - April 10 ~ see Calendar for more information.

Contributers to this edition of The Watch: Jerry Busch, Jim Van Houten, Carol Whitehill, Marian Martinez & Laura Kummerer
Production: Ellie Van Houten & Caroline Rodgers

The Watch
Watsonville Wetlands Watch Newsletter
Post Office Box 1239
Freedom, CA 95019-1239

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