Sunday, March 29, 2009

Where the Woodcock Probe

If you walk along a streambank, or pond edge, or any wetland around here you will see the speckled alder (Alnus incana or rugosa). This multi-stemmed shrub is easy to spot this time of year with its "speckles" (white lenticels on the stem - tiny openings that allow gas exchange), buds, cones, and catkins. The coarse, toothed leaves will not emerge and close in the alder thicket for another month or more.

Alders are monoecious, that is the male and female flowers ("catkins") are distinct from each other, but occur on the same plant. The catkins form in the fall, then overwinter, ready to open or flower in spring (any day now).

I took these photos yesterday near our home.

The male catkin is slender, cylindrical, hanging in clusters of 3 to 5 from short leafless branches.


The female catkin is conelike, droops slightly, usually in clusters of threes.

The fruits look like tiny cones. They cast their seeds in the fall; the dried cones remain until spring.

Woodcock seem to be everywhere this year and they are quite fond of "alder swales." Their peenting and twittering is often heard in an opening that is close to the alder thickets. Woodcock probe the moist soils beneath alders for their favorite food -- earthworms, which make up 50 to 90% of their diet. Young alder provide the best cover and safe probing sites for woodcock.

As alder ages, approaching 20 to 30 years, the stems become thick and the clump leans over, opening the "canopy" to more sunlight. This creates less cover for the woodcock and the earthworms move deeper as the soil is warmed by the sun. Older alder swales can be cut back to the ground to allow a new generation of growth; over time it will provide good habitat again. It is best to cut only a portion at a time and in winter when the ground is frozen.

Beaver clip alder stems for use in their dams and lodges. Goldfinches, pine siskins, and redpolls glean seeds from the mature fruits (cones), and grouse like the buds and catkins. Look for the alder and woodcock also are probably close at hand.

3 comments:

  1. Maybe you might know this...I've been wondering about earthworms and woodcock. They say earthworms are not native to northern, glaciated areas, but woodcock are. For such a specially adapted species as woodcock, if earthworms were only recently introduced to places like Minnesota, what did they eat before?

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  2. Hi Deb,

    Yes, a very curious thing that most of the earthworms in New England are also apparently not native. The profusion of our current earthworm population is thought to be an artifact of the land use clearing and agricultural period of the mid-1800s. There were some native earthworms post glacier, so woodcock may have had some available, along with other invertebrates such as centipedes, millipedes, larvae of beetles, flies and other insects. These prey are also somewhat long and wiggly so maybe that's the story. I'm not sure anyone knows yet, since the earthworm lineage is a relatively new find.

    The woodcock population was at its peak in the 1920s and 1930s when the habitat was perfect for them following 10-30 years of farm abandonment. Woodcock are in decline, but it is not clear if the populations are simply responding to natural changes in habitat, back to a mostly forested state, and are therefore returning to a pre-agricultural period. They are a hunted species so there are forces that want to arrest this decline.

    I think woodcock are cool, but we should keep in mind that their population changes may be an artifact of our land use history (past and current).

    If you learn more please post, and I will keep trying to find out more about the earthworm-woodcock connection. This might be fodder for a future post!

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  3. Hi

    Just wanted to chime in on the earthworm and woodcock issue. Earthworms appear in Native Ameican myth and lore, so at least some species were here before the European invasion. It especially makes since given that we have other species, like the woodcock, that are somewhat worm dependent.

    It is interesting that mostly people of European descent are now determining what was here when there were only Native Americans. How European of them!

    We could talk about dandelions and their preeuropean existence, but that's another story....

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