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About Applegater. (Jacksonville, OR) 2008-current | View Entire Issue (May 1, 2019)
Applegater Spring 2019 13 BIRD EXPLORER Difficult ID of juvenile Bald and Golden Eagles BY PETER J. THIEMANN Eagles are more visible in late winter and early spring as they often congregate near open water where waterfowl is present. In southern Oregon, there are two species of eagles: the Golden Eagle and the Bald Eagle, our National Bird. A mature Bald Eagle is easily identified by its white head and tail. There is nothing “bald” about our Bald Eagle, which is really a misnomer. A far more appropriate name would be Sea Eagle due to its association with water. Juvenile Bald Eagle (left) and mature Bald Eagle (right). Photo courtesy of peterjthiemann flickr photo stream. Juvenile female Bald Eagle (top) with male Golden Eagle (bottom). Photo courtesy of peterjthiemann flickr photo stream. Butterflies benefit from native herb BY LINDA KAPPEN When I think of stinging nettle (Urtica dioica), I think of its many uses. This herbaceous flowering plant has long been used as a source for medicine, food, tea, and dyes for fabric. Nettles make excellent companion plants, helping to produce healthy herbs and vegetables. They also serve as a larval food plant, almost exclusively, for three species of Pacific Northwest butterflies and for other lepidoptera in locations all over the world where nettles grow. In our region, stinging nettle grows in the understory of forests and near rivers, creeks, or wetter meadows in mountains and valley bottoms. The stinging nettle has needlelike hairs that, if brushed against, can sting your skin much like a bee. This is a defense against herbivores. The three butterfly species found locally that use the stinging nettle almost exclusively are the Red Admirable, Milbert’s Tortoiseshell, and Satyr Anglewing. All three belong to the butterfly family Nymphalidae, and all three overwinter (hibernate) in our area. Red Admirable The wingspan of a Red Admirable (Vanessa atalanta) can reach up to two and a half inches. This very beautiful butterfly is black with bright scarlet bands and white spots at the tips of its forewings. Eggs are laid singly. Stinging nettle (oureverydaylife.com). The Bald Eagle is a closely related cousin to the Eurasian Sea Eagle, which looks similar, but without a white head. The ranges of Bald and Golden Eagles overlap, so it is possible to see them together and competing for prey. I have Larvae feed on stinging nettle, making shelters of folded leaves for protection while they feed. Older larvae will make nests tied together with silk. The Red Admirable will overwinter as an adult depending on seasonal weather. If overwintering occurs, it sets a good chance of numerous broods. I have witnessed a third brood toward the end of summer in the recent past. I have seen the Red Admirable fly during warmer days in early February to later dates in early fall. Mostly we see it in flight from May to October. The butterfly will use many nectar sources, including sap, bird droppings, and flowering plants, such as hyssop, rabbitbrush, fireweed, and many more. Its range is the entire Pacific Northwest, from sea level to high mountains. It can be seen in moist woods, fields, meadows, and mountain seeps. Milbert’s Tortoiseshell The wingspread of the Milbert’s Tortoiseshell (Aglais milberti) reaches up to two inches. Its wings have a chocolate- colored base with two-toned bands of orange to yellow and blue crescents toward the edge of the hindwings. It lays its eggs in masses. The behavior of the larvae is like that of the Red Admirable. This butterfly will also break hibernation on warm, late-winter days and can be seen in April and throughout the summer. The Milbert’s Tortoiseshell will nectar on spring flowers, sap, Douglas aster, pearly everlasting, and other plants. In the Pacific Northwest, it ranges from southern Alaska down to California and Nevada and can be seen in wet areas, mountain seeps and meadows, and moist woodlands. Satyr Anglewing The Satyr Anglewing (Polygonia satyrus) can reach a wingspread of two and a quarter inches. Its open wings display a bright yellow-orange color with black spots and a triangular black spot on both hindwings. Eggs are laid singly or in stacks or groups. The Anglewing larvae make shelters by eating the leaves of the stinging nettle, pulling them down and fastening the edges with silk. This butterfly also overwinters and can be seen in flight from February to early November. Adults nectar on tree saps, rotting fruit, lilacs, many thistles, and other flowers. This butterfly can be seen in many habitats such as parks, fields, valley bottoms, openings in riparian woods, canyons, and near streams. The range is all of the Pacific Northwest and also the Great Lakes states. Native stinging nettles or other nettles should be saved in our parks, water ways, woods, cities, and surrounding countryside. Eliminating the nettles would decrease the chances of seeing all three of these beautiful butterflies in our towns and parks. Interesting facts The name “Red Admiral” is a corruption of the original name, “Red Admirable,” which has been in use for over 250 years. The Red Admirable is of the genus Vanessa, but other admirals, like Lorquin’s Admiral and Weidenmeyer’s Admiral, belong to a different genus called Limenitis. Linda Kappen humbugkapps@hotmail.com seen them both on winter kills Peter J. Thiemann in Yellowstone National Park. Here in southern Oregon I was fortunate to capture a unique image of a large juvenile female Bald Eagle with a male Golden Eagle. A close look will show the head size difference with that enormous beak on the Bald and larger talons on the Golden. This comparison is very helpful, as juvenile Bald Eagles are often mistaken for Golden Eagles because they don’t yet have a white head or tail, which come, for both sexes, around age three to four. I posted the juxtaposition of the two eagle species online and received many comments, including some from viewers asking about cross-species relations. It certainly is a unique photo; however, the explanation may be simple. The pole they are sitting on is not a power pole but rather a pole specifically erected for raptors near water and large concentrations of waterfowl. So, it may have been just competition for a prime perch that brought the two together. We will never know. Peter J. Thiemann peterjthiemann@yahoo.com Red Admirable. Photo: Linda Kappen. Milbert’s Tortoiseshell. Photo: Linda Kappen. Satyr Anglewing. Photo: Linda Kappen.
