Hooded merganser male (Lophodytes cucullatus)
There were nine attendees on Friends of Oaks Bottom’s fall nature walk, Saturday, November 9th. Joshua Meyers and John Sparks were the official guides, but we were fortunate to be joined by Laura Guderyahn, one of Portland Parks’ five urban ecologists. Laura contributed much interesting information about refuge projects. It took us about three hours to do our usual circuit of the bottomland, and there was lots to see!
Most of the small birds have already passed through on their fall migration, but there were several species of waterfowl settling in for the long haul. These included rafts of wood ducks in the willows, a number of common and hooded mergansers, ring-necked ducks, and green-winged teals.
Great egret (Ardea alba)
A large number of great egrets were standing, stalking, and snoozing among the dead willows along the edge of the pond. Everywhere we looked there seemed to be a great blue heron. Double-crested cormorants were perched on snags out in the watery expanse.
Ruby-crowned kinglet (Regulus calendula)
As for other birds, Joshua pointed out a number of ruby-crowned kinglets feeding in the shrubbery. We got a close up sighting of a kingfisher, and a couple of bald eagles had stationed themselves on a sand bar in the Willamette. A hairy woodpecker investigated a snag on the bluff, while nuthatches were heard but not seen.
Western red-backed salamanders (Plethodon vehiculum)
Laura rolled some logs and came up with a couple of small and very wriggly western red-backed salamanders. Laura has done detailed salamander studies in the Bottom and explained that the area supports the highest density of this species in the urban area. Also on the amphibian front, we were frequently treated to the calls of male Pacific chorus frogs.
Black-tailed deer male (Odocoileus hemionus columbianus)
A couple of black-tailed deer almost stumbled into us when we were at Tadpole Pond. The male was definitely scenting the somewhat bemused female in front of him! When we were on the Springwater Corridor, John spotted a large ripple spreading across the main pond. We lifted our binoculars and were able to count a bevy of six otters coursing diagonally across the surface towards the dead willow forest on the far bank. Near the otters’ destination, we pointed out the beaver lodge, and Laura informed us that beaver “wars” may have been the cause of two corpses she had recently discovered.
Garlic mustard flowering in the spring (Alliaria petiolata)
Plants, both native and non-native, were also a major topic of discussion on the walk. Laura couldn’t help ripping out some garlic mustard on the bluff, explaining that this invasive plant is allelopathic, i.e. it produces chemicals that inhibit the growth of other plants, including native species. Garlic mustard has been used as a spice or salad in Europe, and some of us chewed on the fresh leaves (a taste somewhere between mustard and garlic, needless to say). We also discussed the disadvantages of having native cottonwoods in your yard, the difficulty of eradicating invasive reed canarygrass, and the use of Galerucella beetles to eradicate the pond’s swath of purple loosestrife.
Friends of Oaks Bottom conducts these nature walks once a season. Our next one will probably be in February. If you’re on our email list, you should receive a notification to sign up!
