I planted the red-flowering currant for hummingbirds, which do pop by now and then, but am equally happy to see Yellow-faced Bumblebee queens make use of the blossoms.Wandering on a mudflat, puzzling over lugworm leavings. Not far off, a large volcano snoozes.
Wednesday, April 7, 2010
Queen bee.
I planted the red-flowering currant for hummingbirds, which do pop by now and then, but am equally happy to see Yellow-faced Bumblebee queens make use of the blossoms.Tuesday, April 6, 2010
Gullstroms.
Late afternoon or early evening, thousands of Glaucous-winged Gulls clock out at the Delta Landfill and head north to spend the night along the Fraser River or Burrard Inlet. Sometimes they fly in disciplined goose-like Vs, but other times they form large, wheeling clouds that slowly waltz across the sky.
I call these "gullstroms." I'm not sure if they are weather-dependent, or are due to whatever was consumed that day at the dump. I'm leaning toward the former. It seems that they do this on blustery days, taking advantage of bouncy air currents. I also think they do it as a social behaviour, and as a means of having fun. Being a gull is not simply rooting through trash and fighting over half-eaten McNuggets. It's also about having fun.
Monday, April 5, 2010
Sprinter.
Sunday, April 4, 2010
Paradise drained. A frog's perspective.
One of the most endangered amphibians in Canada is Rana pretiosa, the Oregon Spotted Frog. I have previously posted about recent efforts to conserve it. The chief factor in the frog's precipitous decline over the past century or more has been habitat loss. It is the most aquatic of our ranid frogs, and lays its eggs communally in shallow, weedy wetlands, the sort found in low-lying areas prone to flooding.
It is likely, based on present and known historical breeding sites for R. pretiosa that the flat pan of rich farmland between Abbottsford and Chilliwack BC, known as the Sumas Prairie, contained prime habitat for this frog.
Until the early 1920s, this area contained a wildly undisciplined body of water called Sumas Lake, which during spring run-off could fill the valley south of the Fraser River between Sumas Mountain (the Canadian one; the Americans have one too), and Vedder Mountain, which is shared by Canada and the US. It would stretch from south of what is now the urbanized part of the City of Abbottsford to below the US border, and northeast across what is now the farmland of Chilliwack. Its extent changed from year to year, depending on amounts of winter-spring rain and mountain snowmelt.
You can assume that Oregon Spotted Frogs would be very happy with this situation. As the lake receded, impermanent shallow, plant-filled ponds would remain in which to lay eggs.
A smaller, shallow lake was present year-round, its outline represented by the blue polygon above. The wetlands around its perimeter would have provided prime frog habitat.
In the late 19th and early 20th centuries, Euro-Canadians were their own flood, filling the region and recognizing its farming potential. It is difficult to farm in land that is frequently, not always predictably, flooded. It is also difficult to build transportation infrastructure across such a a landscape.
(Although if you did, I imagine it would look like this).
In 1919 it was decided the lake would be drained. In 1924 the Vedder Canal was excavated to channel the flow of the Vedder(Chilliwack) River, which enters the lowland from the north end of Vedder Mountain, across what was to become the Sumas Prairie to the Fraser River, the banks of which were diked. Floodwater from the south was flushed on through, and floodwater from the north was blocked. End of lake.
There are presently three known extant populations of Oregon Spotted Frog in Canada. One is in Aldergrove, about nine miles west of Abbottsford (and the once western end of flooded Sumas Lake) and five miles north of the border. It's not far off the left side of the map. Two more are near Agassiz, BC, which is on the north side of the Fraser River, 11 miles upstream from Chilliwack, not far off the right side of the map.
But they're far apart from each other.
The disparateness of these Canadian localities is characteristic of the distributions of the frog in Washington and Oregon, the only two states in which populations remain. (They formerly also occurred in California, but there are now extirpated). For innumerable reasons, significantly-sized wetlands and their associated ephemeral breeding habitats have been changed, lost. The distribution of the species has become fragmented, reducing or removing the chances for successful dispersal. A single catastrophic event, man-made or natural, can eliminate a population.
Certainly in 1919, there was little thought of conserving a pain-in-the-neck lake for the sake of a frog. The Sumas Prairie is one of Canada's most productive agricultural areas. It's not likely to be turned back into a lake any time soon.
There remains one small remnant of Sumas Lake. It's a small wetland, snug against the south side of Sumas Mountain. A few years ago a concerted effort was made to determine if Oregon Spotted Frogs occurred there. None were found.
Rana pretiosa. Photo courtesy of Mountain View Conservation and Breeding Centre Society .Ref: Haycock, R.D. 2000. COSEWIC Status Report on the Oregon Spotted Frog Rana pretiosa in Canada. Online link - not functioning at time of posting.
Saturday, April 3, 2010
What wind?
Yesterday was the windiest in some time. Not only was the wind strong (gusting to >85 k), it was relentless, continuing for more than 24 hours. I went for a walk during the worst of it, because, well, it was there.I wish there were an adequate way to record and reproduce the sound. You would need multiple microphones, some means of preventing microphone huffage (yes, I just invented that word), and a theatre with speakers of all sizes in all directions. Sensurround!
Although continuous, the wind was not homogeneous. You could hear the stronger gusts approaching, unseen vortices ravaging one tree and then the next. And each tree, with its characteristic form and structure and degree of leafiness, writhed and wailed with its own rhythm and pitch. A plum, and then a cedar, and then a pair of Douglas firs, and so on. And then it was upon you, pushing you one way or another, removing your hat, turning your umbrella inside-out were you fool enough to carry one.
In the midst of all this was a pear tree in flower, and among its branches was a tiny bird, flitting from blossom to blossom, seemingly unaffected by the storm. Are hummingbirds too trifling for the wind to trouble with? Are they not seen by gusts bent on ripping branches off conifers?Friday, April 2, 2010
Stuck.
It's raining, windy and cold, not the Good Friday anyone would have ordered. So no field trip today. The birds and plants will have to wait.
Stuck at home with bored kids. We tried egg-decorating, but it never turns out the way you hope. Bored, disappointed kids.
But it could be worse. We could be the types who feel a need to take advantage of the almost-at-par dollar and head south.
2-3 hour border waits.
Stuck at home with bored kids. We tried egg-decorating, but it never turns out the way you hope. Bored, disappointed kids.
But it could be worse. We could be the types who feel a need to take advantage of the almost-at-par dollar and head south.
2-3 hour border waits.
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