{"id":15172,"date":"2024-08-22T15:23:38","date_gmt":"2024-08-22T20:23:38","guid":{"rendered":"https:\/\/uwm.edu\/field-station\/?p=15172"},"modified":"2024-08-22T15:23:40","modified_gmt":"2024-08-22T20:23:40","slug":"american-copper-butterfly","status":"publish","type":"post","link":"https:\/\/uwm.edu\/field-station\/bug-of-the-week\/american-copper-butterfly\/","title":{"rendered":"American Copper Butterfly"},"content":{"rendered":"\n

Greetings, BugFans,<\/p>\n\n\n\n

The BugLady found this beautiful little butterfly in the dunes at Kohler-Andrae State Park recently. She doesn\u2019t see coppers often, and she always forgets how small they are \u2014 a tad smaller than a Pearl Crescent. Coppers are in the family Lycaenidae along with the Blues, Hairstreaks, and Harvesters.\u00a0<\/p>\n\n\n\n

The first thing to know about the American Copper (Lycaena phlaeas<\/em>) is that it probably<\/em> isn\u2019t native.\u00a0Some researchers believe that it\u2019s the same species as a European-Eurasian-North African butterfly called the Small, Flame, or Common Copper in English,\u00a0Lille Ildfugl<\/em>\u00a0in Danish,\u00a0Acobreada<\/em>\u00a0in Portuguese, and\u00a0Manto Bicolor<\/em>\u00a0in Spanish.\u00a0Bugguide.net calls it the \u201cthe most widespread species of the genus Lycaena, and among the most widespread of all butterfly species<\/em>.\u201d It is believed that the ancestors of the American Coppers in the Eastern US came over on the boat with the early settlers, probably from Scandinavia, probably in shipments of hay.\u00a0The other guess is that it\u2019s a Holarctic species \u2014 one that is native to the whole top of the world.\u00a0DNA analysis would answer that question.\u00a0<\/p>\n\n\n\n

\"American<\/figure>\n\n\n\n

Adults nectar on a variety of flowers, many of them in the composite\/aster family.\u00a0This butterfly found something to like about Spotted knapweed, an invasive that likes poor soils.\u00a0Caterpillar host plants are two non-native members of the buckwheat\/smartweed family \u2014 Sheep sorrel (sour dock) and, to a lesser extent, curly dock.\u00a0The fact that the American Copper\u2019s two main food plants also came over on the boat is considered proof of its non-native status, though some native butterflies do adopt introduced plants.\u00a0Further, the native plants that are related to Sheep sorrel and curly dock are wetland plants, and this is a butterfly of dry habitats. As their host plants followed the edge of the frontier west, it is said, the American Copper trailed behind. \u00a0<\/p>\n\n\n\n

In North America,\u00a0American Coppers are\u00a0mostly found east of the Rockies, north to the Tundra.\u00a0They\u2019re not found in the Deep South, except in the mountains, where they eat Mountain sorrel.\u00a0<\/p>\n\n\n\n

\"American<\/figure>\n\n\n\n

[Quick botanical aside:\u00a0Mountain sorrel is an alpine plant with its own origin story. Researchers found that it originated in China at least 11 million years ago, moved east into Russia and then into North America by 4 million years ago, west into Western Europe by two million years ago, and that it entered Greenland from both east and west \u2014 a circum-arctic species.]\u00a0<\/p>\n\n\n\n

American Coppers frequent\u00a0the habitats of their caterpillar food plants \u2014 barrens, abandoned fields, powerline and railroad rights-of-way, and especially dry, disturbed spots like vacant lots and road edges. And dunes.\u00a0The fabulous \u201cButterflies of Massachusetts\u201d website notes that this is a species that benefited from the clearing of forests for agriculture and timber in the 1700s and 1800s and that it does not do well in heavily developed or landscaped areas.\u00a0\u00a0\u00a0<\/p>\n\n\n\n

They are active, especially on sunny days \u2014 fast and erratic butterflies that fly a foot or two above the ground and may also hover or glide \u2014 strong flyers that can show up quite a ways from home.\u00a0They also bask on the ground.\u00a0Clarence Weed, in\u00a0Butterflies Worth Knowing\u00a0(1922) says that they \u201cbegin their day\u2019s work early in the morning and continue well into evening.\u00a0Then they find a roosting-place, head downward on a blade of grass, where they sleep until wakened by the morning sunshine<\/em>.\u201d \u00a0<\/p>\n\n\n\n

Females and males look similar, with wingspans of 7\/8\u201d to 1\u00bc\u201d.\u00a0They\u2019re beautiful with their wings closed, and spectacular with their wings open<\/a>.\u00a0The downy caterpillars are about \u00be\u201d long and may be greenish-yellow or have a rosy trim<\/a>.\u00a0\u00a0\u00a0\u00a0\u00a0<\/p>\n\n\n\n

Males are territorial and feisty, watching for females from perches on vegetation and chasing any insects that fly by. Sources said that they react to the shadows of birds, and renowned lepidopterist Alexander Klots reported seeing a male American Copper go after an airplane.\u00a0Females select males by landing nearby and displaying their wings, and they mate perched on vegetation<\/a>.\u00a0If they fly while coupled,\u00a0she<\/em>\u00a0totes\u00a0him<\/em>, rather than the other more common way around. \u00a0<\/p>\n\n\n\n

Eggs are laid on the upper surface of the host plant\u2019s leaves or stem, and the sluglike caterpillars shelter near the base of the plant by day and feed by night on the underside of the leaf.\u00a0There are several generations per year, and the final brood overwinters as larvae in leaf litter at the base of the plant, pupating for three weeks in the following spring (though some sources say that they overwinter in the pupal stage).\u00a0Adults live for two, all-too-brief weeks.<\/p>\n\n\n\n

Caterpillars of some of the other Lycaenids consort with ants (they are\u00a0myrmecophiles<\/em>) \u2013 ants care for them in return for a honeydew-like substance made by the caterpillar. A few sources speculated that American Copper caterpillars might enjoy such a relationship, too, producing chemicals that attract ants.\u00a0<\/p>\n\n\n\n

Three other items of business:<\/p>\n\n\n\n