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Posts Tagged ‘ecology’

Two piliated woodpeckers on tree

Pileated woodpeckers on the Mt. Tamalpais Watershed (Photo by Ian Austin)

The Marin Wildlife Discovery Day will be an opportunity to learn about and celebrate the rich diversity of wildlife in Marin. There are over 150 species of birds that live and breed in Marin, our creeks support some of the best coho salmon populations in northern California, and our hills are home to California’s top predator, the mountain lion. Come enjoy hands-on science learning for the entire family!

The event will be Saturday, October 25, 10:00 a.m. – 2:00 p.m. on “Children’s Island” in the lagoon at the Marin Civic Center. Parking will be available at the Marin Fairgrounds. Admission is free.

The Discovery Day will be hosted by many of the groups and organizations that work to preserve, understand, and protect Marin’s amazing wildlife. The event is organized by Marin County Parks with partners Marin Municipal Water District, Golden Gate National Parks Conservancy, River Otter Ecology Project, Felidae, Pepperwood Preserve, Project Coyote, Friends of Corte Madera Creek, College of Marin, Redwood High School-Next Generation, Manor School Green Team, and more.

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Four deer in the backyard

Backyard visitors

The tug of my heart found me traveling to Bend, Oregon, to see six grandchildren where they reside. The road trip was a surprise as I expected to see some fall color in the trees, but summer was holding on to various shades of green. Nonetheless, the scenery was delightful.

My son Randy and his family live on the south side of town in an area that reminds me so much of Lake Tahoe. Thick groves of aspen and pine trees grow in profusion. Sitting on the back deck surrounded by this woodland brought such peace. The twins, Grace and Chris, pointed out the new fence that replaced the 6-foot fence that once stood at the back property line. They were quick to let me know this fence was built much shorter to accommodate the deer trail through their yard. The gate between the two yards was constructed with a latch enabling the gate to remain open for deer access. What a concept!

Vine maple

Vine maple (Acer circinatum)

Living with deer requires a different kind of landscape and attitude. As I looked around my son’s yard, I noticed he uses plants that are not often browsed by the beautiful four-legged friends. Native plants such as Mahonia (Oregon grape) and Acer circinatum (vine maple) border the perimeter of the garden. I was told more than one doe used this area for birthing. I could envision the deer resting under the vine maples in a month or more when these plants would show their true color combination of reds, oranges, and yellows.

Randy and I walked around the garden in the morning and found a doe and her two fawns nestled under the big pine trees. I marveled that the deer didn’t browse on the annual color on the back deck. It was almost as if they respected the working relationship between man and beast. As we walked, we spoke of adding a small natural stone basin of water to quench the deer’s thirst. The basin could be positioned to easily capture the spray of water from the lawn irrigation system, eliminating the maintenance to keep it filled.

The concept of living with nature, instead of fighting it, made sense to me. Often we build high fences or spray our plants with repellent to discourage the deer in our midst. Randy and the children’s actions gave me pause for thought. Foraging rabbits and squirrels caused my own vegetable garden to fail this year. I fought their presence instead of providing what they really wanted in the drought-stricken land. As I lamented the frustration of lost vegetables, Jack would remind me that the night marauders were only hungry. It made me wonder how much of the garden would have been untouched had I provided feed for them. My trip to Bend taught me that the winning combination of living with wildlife is to provide shelter, food, and water for them to live in harmony with us.

How have you remedied the wildlife situation in your garden? Are you fighting a losing battle by keeping them at bay? Or do you employ various strategies to live with them?

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by Andrea Williams, Vegetation Ecologist

This is installment seven of a 12-part series on grasses. Read the previous installment here.

Serpentine reedgrass (Calamagrostis ophitidis) is rare. We have tons of it.

Such seemingly incongruous statements happen quite a bit on Mt. Tam, through the magic of the “Matrix of Rarity.” It depends on the scale at which you look. The California Native Plant Society (CNPS), which reviews the distribution of and threats to California’s flora, keeps an inventory of plants and the degree of rarity they display. So statewide (and worldwide), there may be fewer than 100,000 individuals, but if all those individuals are in a three-square-mile area they may seem abundant in that spot.

  Abundant where found Few plants per population
Broadly distributed Common species, e.g. purple needlegrass (Stipa pulchra) Often rare, e.g. semaphore grass (Pleuropogon)—next month’s topic!
Narrowly distributed Often rare, e.g. serpentine reedgrass Nearly always rare

Almost half of our rare plants are restricted to serpentine soils; like wetlands and beaches, these habitat types are finite. Often, rare plants in these spots will be quite common and you may wonder why they’re considered rare at all. Mt. Tam manzanita is actually so common it’s the dominant plant over most of our serpentine soils. Serpentine reedgrass is pickier still, preferring to grow at the edge and in the interstices of serpentine chaparral.

Serpentine reedgrass

Serpentine reedgrass (Calamagrostis ophitidis)

Unlike Mt. Tam manzanita, though, serpentine reedgrass can be found outside Marin in Sonoma, Mendocino, Napa, and Lake counties, although we do have the bulk of it. This handsome perennial grass raises fluffy, open spikes one to three feet above clumps of deep green upright leaves. Some of the finest serpentine reedgrass grassland—a rare vegetation type—can be found along Pine Mountain Road opposite Azalea Hill.

Another factor feeding into a plant’s status is the threat to its populations. Serpentine reedgrass populations on Mt. Tamlapais are pretty stable: No one is bulldozing populations to build things, they don’t need fire to germinate, their habitat isn’t being taken over, no diseases are wiping them out. But in other counties that may not be the case. Like with the drought, we need to consider ourselves lucky that we are where we are and have what we have (90% of average water storage and 40 rare plant species), and continue to conserve.

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by Andrea Williams

This is installment six of a 12-part series on grasses. Read the previous installment here.

Even though I’m a cat person, every February I love to watch the two-day spectacle of the Westminster Kennel Club Dog Show. I’m just a taxonomist at heart, and I enjoy spotting the subtle differences between the American foxhound, Harrier, and English foxhound; or how the different groups came to be and why the Non-Sporting group is such a mish-mosh of breeds. But there are also the subtle cautions offered by announcer David Freese that make me think of gardening: Know your breed and pick the one that’s right for you, and don’t buy into the “fad” or “popular” breeds (e.g., dalmations after “101 Dalmations” came out, or whatever breed wins the WKC). And that brings me to pampas grass (Cortaderia sp.).

Jubata patch in slide area off Hoo-Koo-E-Koo on Mt. Tamalpais

Jubata patch in slide area off Hoo-Koo-E-Koo on Mt. Tamalpais

California’s pampas grasses are two very similar-looking but reproductively different species, and just like irresponsible breeders can churn out sick dogs to capitalize on a fad, irresponsible or ignorant plant breeders can inadvertently introduce pest plants or diseases in trying to create or capitalize on a fad. According to this excellent article in the 2004 Cal-IPC news, pampas grass (C. selloana) was originally brought up from the South American pampas for its striking inflorescences. The white, fluffy plumes are only produced by the female plant; the male plant’s plumes are darker and thinner. So for a while, only female plants were planted and exported, and no spreading could happen without the males. But fads catch on, and inevitably the male plants made their way into the world, as did the similar-looking purple pampas grass (or as I prefer to call it, jubata grass, C. jubata). Jubata grass, nearly opposite the outcross-dependent pampas grass, is apomictic—seeds form from the female ovules without fertilization. This allows it, like the also-apomictic and wind-dispersed dandelion (Taraxacum officinale), to establish new colonies over long distances and take advantage of disturbances.

Most of what we have in Marin is jubata grass; proper pampas grass is mostly strictly coastal, and found in San Mateo and Southern California (although the Richmond-San Rafael Bridge corridor is an excellent spot to see both species side-by-side). Because of its need to outcross, pampas grass can be slower to establish since the winds of chance need to blow both male and female plants within pollination distance. But that also means it may be able to adapt to changes and eventually invade more areas. The hare to pampas’ tortoise, jubata grass quickly covers disturbed and difficult-to-reach sites such as roadcuts and landslides. We try to keep on top of our populations on Tam, and have managed to mostly keep it contained in a few sites and prevent seeding. The good news is, although the seeds are numerous and far-slung—over 1,000,000 per plant traveling many miles on the breeze—they are short-lived, usually only a year. So once the adults are treated and re-invasion of bare ground is minimized, the follow-up is minimal. Better, though, if we’d had an ounce of forethought and prevention a century ago, and not introduced such an aggressive breed.

Don’t plant a pest: Ornamental grasses of the Bay Area region (California Invasive Plant Council)

An aside/post-script: Speaking of capitalizing on fads, a recently invading ornamental (Erigeron karvinskianus) that used to be called “Mexican fleabane” is now being called “Santa Barbara daisy” and people are buying and planting thinking it’s a California native … which it’s not!

 

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by Eric Ettlinger

Coho smolt

Coho smolt

Salmon in California have evolved to follow the seasonal rhythms of wet and dry periods as they migrate between their natal streams and the ocean, and then back again. The fall rains that swell Lagunitas Creek and herald the return of adult salmon to Marin County also encourage young coho salmon to begin their downstream journey to the ocean. In normal years, winter is the time when many of these young salmon migrate from headwater tributaries down to lower Lagunitas Creek, where they transform into silver smolts in preparation for the ocean phase of their life cycle. These smolts wait in the lower creek until April and May before entering the ocean, just in time to take advantage of the spring plankton bloom.

2013 and 2014 have not been normal years, however. Fall rains were infrequent and light, and January was the driest on record. The drought caused a significant delay in salmon spawning and resulted in a much smaller coho run than expected. The extended dry period did, ironically, seem to benefit the young salmon preparing to emigrate to the ocean. Many coho fry were unable to migrate downstream until the rain finally arrived in February, which meant that they weren’t packed together in lower Lagunitas Creek. The habitat in the lower creek can’t support very many young salmon through the winter, which appears to be one of the principal factors limiting the size of the entire coho salmon population. This year, salmon fry spent the winter spread throughout the watershed, and likely spent little time crowded in the lower watershed.

The result was the largest emigration of salmon smolts yet seen in Lagunitas Creek. Biologists with the Watershed Stewards Project, the Marin Municipal Water District, the National Park Service, and the Salmon Protection and Watershed Network counted coho smolts every day between late March and early June as they migrated past traps on Lagunitas, Olema, and San Geronimo Creeks. In typical years the lower watershed doesn’t appear to be able to support more than approximately 11,000 juvenile coho salmon through the winter. This year nearly 20,000 coho smolts emigrated to the ocean.

smolt chart

Click the image above to view full-size chart

What does this mean for the future of coho salmon in Marin County? In the short term, if food is abundant in the ocean we could see 2,000 adult coho return to Lagunitas Creek in 2015 (the most in more than half a century). On the other hand, this year’s smolts were fairly small and may not survive well. Over the longer term, while we can’t recreate this year and prevent coho from migrating to the lower watershed, we can provide more habitat there. A grant currently being considered by the California Department of Fish and Wildlife would fund the construction of five projects in lower Lagunitas Creek to expand side channels and floodplains for coho salmon winter habitat. Hopefully this grant will be funded and the projects will achieve their goals. As with the seasonal migrations of salmon, we’ll just have to wait and see.

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by Andrea Williams

This is installment five of a 12-part series on grasses. Read the previous installment here.

blue wildrye

Blue wildrye (Elymus glaucus)

I know I should like American robins, but I don’t. It’s just that they’re so common. And I kind of feel that way about blue wildrye (Elymus glaucus).

I first learned blue wildrye in Oregon, during those formative summers on a coastal grassland overlooking the mouth of the Salmon River. Being new to grass ID, I really appreciated how obvious it was—four-to-six-foot-tall spires in a foot-wide clump, usually a bluish-green color with short upper blades flagged straight out from the stem. The inflorescence was nice and simple, too, a narrow, bristled spike. No branching, or sterile florets, or measuring or counting veins to worry about. Just blue wildrye, plain and simple. And then I started monitoring grasslands, and I was so over blue wildrye.

Because it was everywhere. So common. And easy to collect, and easy to grow. Just bend the flowering stalks into a bag and “milk” the seeds and the ripe ones slide right out. Then scatter the seeds over a site and next growing season it will be lousy with wildrye. And these are all good things. Like robins. Sharp red breast, jaunty hop, cherry-dew song. But they’re everywhere. So common.

And so it is sometimes: The need for the new, the value we give to rarity overshadows the basic merits of a thing. I just have to remind myself to appreciate and celebrate the common, to see with new eyes instead of wanting my eyes to always see the new.

 

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by Andrea Williams

This is installment four of a 12-part series on grasses. Read the previous installment here.

California oatgrass

California oatgrass (Danthonia californica)

I’m sure you’ve heard the phrase “sowing your wild oats,” but did you know that California wild oats (aka California oatgrass, Danthonia californica) is the grass that loves you back? And they have a secret seed to sow?

I grew to know California oatgrass in Oregon, when I spent my summers on a coastal grassland studying the habitat of the threatened Oregon silverspot butterfly. At first I just liked how obvious it was, three fat spikelets and a little eyelash winking at you where the grass blade met the stem. It wasn’t until my time at Redwood National and State Parks that I appreciated the ingenious strategy this grass employs in reproduction. And it wasn’t until last month that I fully appreciated just how hardy and long-lived California wild oats can be.

Most grasses, California oatgrass included, reproduce through wind-pollinated flowers that turn into seeds; think wheat or rice grains. But oats, California oatgrass included, are tasty and can be browsed down before they have a chance to become a new plant. California oatgrass has a contingency set of seeds in the base of its flowering stalk. These flowers are cleistogamous, meaning—like nuns in a cloister—they are kept shut away. The flowers self-pollinate inside the stem, and when the upper (chasmogamous, opening, like a yawning chasm) wind-pollinated flowers have ripened into seeds and are ready to drop, the stem itself detaches from the basal clump of leaves. This gave rise to a new dance, the “Danthonia Shuffle,” during a native grass seed gathering expedition. Rather than plucking individual seed heads, you can shuffle your feet through an oatgrass-laden path and once a sufficient number of stems have gathered around your shins, just scoop the whole lot up into a bag! You not only have the seeds that haven’t dropped from the seed heads, but you have the straw and the secret seeds as well!

California oatgass secret seed

California oatgass secret seed

California oatgrass, once established, is a hardy and forgiving plant that tolerates mowing well. It does prefer wetter areas in grasslands, where it mixes with purple needlegrass, blue-eyed grass, and the cheery yellow of California buttercups. On Mt. Tamalpais, our oatgrass tends to have three to five spikelets above a clump of slightly greyish green leaves. On the coast, plants tend to be a little greener. Last month, as I was staffing the California Native Grassland Association booth at the Point Molate Beach opening, I looked down at the mowed-and-trampled ground and saw a little oatgrass eyelash winking up at me from an emerald clump of leaves—California oatgrass had survived decades of people walking and mowing and picnicking and parking on it.

And why is it the grass that loves you back? The arrangement of spikelets matches the hand symbol for “I love you” in sign language.

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