American Snout Butterflies in Texas Pecan Orchards
An adult American snout butterfly. Note the adult has the long extension of the face that gives it the appearance of having a large ‘snout.’ (Photo credit: Rebekah D. Wallace, University of Georgia, Bugwood.org)
The larva of the American snout butterfly. (Photo credit: Jerry Butler, University of Florida)
The American snout butterfly ranges from Southern and Central California all the way to Florida and as far south as Argentina. Snout butterflies are migratory, with Texas experiencing irregular migrations between June and October in parts of San Antonio, the Texas Hill Country, and Austin. This mass migration is believed to be triggered by rainfall patterns as population booms are often associated with droughts followed by summer rain. Drought reduces activity in adult butterflies and reduces parasitoid numbers that help keep populations in check, while the summer rains promote the growth of hackberry plants that the larvae feed on. This combination of events leads to the large migration events observed in Texas.
Pecan orchards can be popular flyways for migrating American snout butterflies. While large numbers of these butterflies congregating in orchards can be alarming, they are not known to feed on pecans and thus are not considered a pest species for the crop. Presence of American snout butterfly in pecan orchards are migrants on the search for hackberry plants to lay their eggs on.
