Park Week 9/15/23

Birds of the Week

The big bird news this week in the park was the return of the White-crowned Sparrows. A little flock of about a dozen foraged on the south side of the Native Plant Area. All the ones I saw appeared to be young ones. They still had the brownish streaks on their heads, instead of the sharp black and white of the grownups. They’ve flown in from the Arctic. They can cover 300 miles in a day and fly for two weeks without sleeping. They are amazing birds. Of course, all birds are amazing, but these stand out.

Youth was also the theme of the flock of House Finches that have been roaming up and down the west side. These look like they hatched earlier this year. I’m confident that they hatched right here in the park but I’ve been unable to find any of their nests. The young males have a light brushing of pink or red but still lack the saturated color that they’ll want when it’s mating time.

The Wandering Tattler seemed perfectly at ease among the waves breaking over the rocks on the west side. This bird probably stopped over here for a quick refresher on its migration from mountainous regions of Alaska down to Peru or onward to New Zealand or Australia. They can fly 6,000 miles or more nonstop over water. They’re nicknamed “tattler” because in a group of different species they’re the first to give an alarm when possible danger looms.

On the water, the newsiest bird was this Eared Grebe, seen on Wednesday on the North Basin. It was the only one of its kind, keeping loose company with a gull.

It was also youth week for gulls. I saw a chocolate-colored gull off the west side and was baffled. The Merlin app had no trouble IDing it as a juvenile Western Gull. It takes gulls four years to look like the white and grey adult birds that we commonly see. The next day on the east side I saw a very young California Gull. Or at least Merlin thought it was a California Gull. I’m not at all expert in gulls and rely on the Merlin app when in doubt. It’s not always right, but it’s generally smarter than I am.

Pelagic Cormorants are a bit smaller than the far more common Double-crested Cormorants. Their bills are more slender and they lack the orange cheeks. Out on the breakwater on the west side where cormorants hang out, the Pelagics stay farther out and keep to themselves. This pair was diving for breakfast on the east side of the park, working from south to north just a few feet from the rocks.

Those are the birds I saw. The ones I didn’t see: Yellow-rumped Warbler, Western Flycatcher, and the “big hawk” that caught a Gopher Snake on a southside hill, with a little group of preschoolers and their carers watching in awe. Nobody got a picture.

Blue in Green

This Great Blue Heron has been hanging around the Open Circle Viewpoint and the surrounding area most of the week. I happened to catch it foraging at low tide on the rocks east of the seasonal Burrowing Owl Sanctuary. The bird’s feet have no trouble keeping traction on the slippery seaweed. When it hops to another rock, it opens its mighty wings for a moment to give it lift. For me, the gem of this video is the second when the bird vocalizes. (I’ve boosted the audio for this sound.) It’s quite rare to hear the Great Blue express itself; I’ve only heard it once before. I’m guessing it was saying, “This place sucks, nothing to eat!” Shortly afterward, the bird flew off.

Mower’s Weeds

The weed with yellow flowers that has popped up all over the southeast grassland and elsewhere looks like dandelion, but isn’t. It’s Bristly Oxtongue, Helminthotheca echioides. It has puffy round seed heads like dandelion, but the leaves are dull and have sharp bristles or pimples. It has no medicinal or nutritional virtues, whereas dandelion makes a decent salad.

Bristly Oxtongue might properly be named Mower’s Weed. It thrives in the wake of the mowing machines. Wherever the mower has gone, this weed is sure to follow. Where the mower runs repeatedly, like over the southeast meadow, the weed achieves abundance. In the Protected Nature Area on the north side of the park, the mower has chopped down some ten or twelve feet of vegetation next to the paved trail. In that strip the oxtongue thrives, and from there it tries to colonize the northside grassland, but it can’t get very deep, as the native grasses eventually stifle it. The compact grassland on the slope where the Red-winged Blackbirds breed in springtime (in good years), is totally free of this weed. This meadow is never mowed, and the wall of Fennel protects it from the mowed strip along the paved pathway. The oxtongue is similar in this respect to the hated foxtail (wild barley). Foxtail too is a fruit of the mower, abundant where the mower rules, scarce where it visits occasionally, absent where the mower cannot go. We should not blame Nature for these weeds. They are the children of our machines.

Invader’s Kryptonite

Not every plant in the Native Plant Area is a native. Dave Kaplow, one of the pioneers who established the Native Plant Area in the early 1980s, related that the City’s landscape boss at the time wasn’t on board with native plantings, and forced his team to plant exotics as a condition of getting their grant money. A favorite of conventional urban foresters at the time was Myoporum laetum, the Ngaio tree, a/k/a mousehole tree or lollipop tree. Myoporum is a native of New Zealand, where it covers large tracts of coastal land. It grows fast, provides shade, and needs little summer water when established. These virtues led urban foresters in the U.S. to favor it as a street tree despite the fact that its leaves and cherry-like fruit are toxic and children playing near this plant should be supervised.

Planted in a park, the Myoporum is invasive. Its fast growth and aggressive spread crowd out slower natives, earning it a listing with the California Invasive Plant Council. In the Native Plant Area, Myoporum has taken over the northwest corner and owns spreading pockets in other locations. It boxes in a native California Buckeye and elbows a native Toyon, among others.

But this invader has its kryptonite. That’s a tiny insect, a thrip, Klambothrips myopori, that specializes in this tree. The thrip is thriving now on one of the myoporum in the northwest corner. The larvae quickly curl up the leaves and seal themselves inside. The normally pretty foliage becomes hideously deformed, as my photo taken last week demonstrates. The tree eventually dies. There is no effective defense against the thrip. The only cure is to remove the tree. As the Cal-IPC website puts it, “Mature plants are commonly treated by cutting at ground level and painting the stump with an herbicide.” Because of its invasiveness and its susceptibility to the thrip, myoporum are no longer used in urban forestry. Removal of the infested tree, and removal of all the myoporum in the Native Plant Area, would be a benefit for the environment and would free up space in the Native Plant Area for native plants.

Read more: UC Riverside | Marina Trees & Garden | UC IPM | PlantRight

Another New Waterfront Plan

The Parks, Recreation and Waterfront Commission this Wednesday evening began discussion of a new document from the City Manager, the Waterfront Specific Plan Draft 9/8/23. This item is the successor to the Berkeley Marina Area Specific Plan (BMASP) of early 2022 that stirred up a huge protest movement with its proposals to commercialize Chavez Park. The new document abandons those projects. It is a large improvement. But there are some issues. The authors reveal considerable lack of familiarity with the park and its history. The City’s draft document is a colorfully illustrated 285-page booklet available as a PDF here. I’ve drafted a four-page comment available as a PDF here.

Bird Data Redlined

Bird observations follow mortgages. They are abundant in affluent residential areas and scarce in minority neighborhoods. Federal housing policy in the 1930s zoned areas into “green” where investment was considered “safe,” and “red” where investment was discouraged. Areas where Black people lived were systematically classed “red.” Decades later, this pattern, called redlining, shows up in recorded bird observations with data banks like eBird. There is an abundance of bird observations in predominantly “green” (white) districts, and a paucity in others.

Ecologist Diego Ellis-Soto studied reported bird observation in 9000 neighborhoods in 200 US cities. ““You can better predict where you have data on birds based on systemic racism — redlining maps from 1933 — than climate, tree cover or population density, everything a bird should actually care about,” says Ellis-Soto.

The disparity in data affects funding for bird studies and bird conservation. Areas with many observations get more money. It’s a “self-perpetuating negative loop,” says Chris Schell, an urban ecologist at UC Berkeley. A discussion of the data appeared in Nature Sep. 7 and is open to the public.