The spotted lanternfly, Lycorma delicatula, is an invasive planthopper first detected in Pennsylvania in 2014. Native to Asia, this insect poses a significant threat to agriculture and natural ecosystems. They feed on the sap of a wide range of plants, including important crops like grapes, hops, and stone fruits, and various hardwood trees. Their feeding activity can weaken plants, reduce crop yields, and even lead to vine death in vineyards. Beyond direct plant damage, spotted lanternflies excrete honeydew, a sugary substance that attracts other pests and promotes sooty mold growth.
Avian Predators of Lanternflies
While initially thought to lack natural predators, observations confirm several bird species prey on spotted lanternflies. Chickens are often reported as consumers. Various wild bird species have also been documented feeding on them.
Northern Cardinals, Gray Catbirds, Blue Jays, and Tufted Titmice are commonly observed eating spotted lanternflies. Species such as red-bellied woodpeckers, great crested flycatchers, and Eastern bluebirds also consume them. These predation events are often opportunistic, meaning birds eat lanternflies when encountered.
Factors Influencing Bird Predation
The diet of spotted lanternflies influences their palatability to birds. Lanternflies often feed on tree-of-heaven (Ailanthus altissima), which contains bitter, potentially toxic compounds. When lanternflies consume sap from this tree, they sequester these chemicals, making them unpalatable or toxic to predators. This can deter birds from consuming them.
Spotted lanternflies also exhibit aposematic coloration, with bright red and black markings. This warning coloration signals to predators that the insect may be toxic or unpalatable. As a newly introduced species, native birds may not instinctively recognize spotted lanternflies as a food source. However, some research suggests birds may not show a strong preference between lanternflies that have or have not fed on tree-of-heaven.
Ecological Impact of Bird Predation
Birds contribute to the natural control of spotted lanternfly populations, but their overall impact is localized and opportunistic rather than a major control agent. While community science initiatives have documented hundreds of predation events, these instances may not be sufficient to curb widespread infestations. Removing tree-of-heaven can enhance bird predation, as this reduces the bitter taste of lanternflies and makes them more appealing.
Encouraging bird activity by providing shelter, food, and water can support managing lanternfly numbers. Despite these efforts, bird predation alone is unlikely to eradicate the spotted lanternfly due to its rapid reproduction and lack of specialized natural enemies. Ongoing research into bird predation patterns offers insights into potential integrated pest management strategies.