On 21 August 2016, Erika and I found a dozen Eastern Tailed-Blues. Many butterflies feed on pollen, but others prefer urine and, in this case, excrement. Larvae eat various legumes, which are common along our trail in the Carleton arboretum. The larvae secrete substances that attract ants, which, in turn, protect the larvae from various predators.
Tailed-blues are hard to photograph, since, when they perch, they keep their wings folded. They look gray, until, suddenly they flutter away in a blaze of azure. On this day, they looked like sailboats keeling against the wind. Occasionally a gust knocked a few completely over.
These butterflies’ tails are just visible in this photograph. Note the tails along the wing edges, opposite the orange spots, on the furthest left butterfly. Often the tails wear off as the season progresses.