The spotted lanternfly, an invasive insect native to Asia, has established itself as a significant agricultural and environmental pest across North America. First identified in Pennsylvania in 2014, this species has since spread throughout the Northeast, Mid-Atlantic, and Midwest, causing considerable damage to a variety of crops and native plants. Economic assessments indicate that this pest could lead to substantial annual losses, potentially reaching hundreds of millions of dollars in affected regions. This article explores the evolving relationship between North American bird populations and the spotted lanternfly, examining the extent of bird predation and the factors influencing this interaction.
Birds That Consume Spotted Lanternflies
Researchers and citizen scientists confirm that various bird species consume spotted lanternflies. Over 33 different avian species have been documented preying on these insects, including generalist insectivores such as Northern Cardinals, Gray Catbirds, Blue Jays, Tufted Titmice, Woodpeckers, and Chickadees. Chickens are also frequently reported eating them, often in backyard settings. Birds consume lanternflies in both nymphal and adult stages, indicating adapting predatory behavior among native bird populations towards this new food source.
Reasons for Variable Bird Predation
The interaction between birds and spotted lanternflies is not straightforward, with several factors influencing whether a bird will consume the insect. A significant deterrent is the lanternfly’s ability to sequester defensive chemicals from its primary host plant, the Tree-of-Heaven (Ailanthus altissima). These chemicals render the lanternfly bitter and unpalatable. Birds have been observed reacting negatively to these insects, sometimes even vomiting after ingestion. Research suggests birds show a preference for lanternflies that have not fed on the Tree-of-Heaven.
The bright red and black coloration of adult spotted lanternflies acts as an aposematic signal, warning predators of their unpalatability or toxicity. This warning coloration helps birds learn to avoid these insects after a single unpleasant experience. Since spotted lanternflies are a novel food source in North America, native birds are still in the process of learning and adapting their foraging behaviors. Some birds may learn to bypass the unpalatable parts, such as plucking off the wings, before consuming the body. While their specific nutritional value is still being researched, other traditional insect prey may offer a more favorable energy-to-effort ratio for many bird species.
Broader Ecological Context
While bird predation on spotted lanternflies is occurring, it is generally considered a supplementary control factor rather than a primary solution for large-scale infestations. Bird activity forms one component of a multi-faceted approach necessary to manage this invasive pest. The overall effectiveness of birds in significantly reducing spotted lanternfly populations across wide areas is still being investigated. Encouragingly, the removal of Tree-of-Heaven from local environments can make spotted lanternflies less bitter and potentially more appealing as a food source for birds, thereby increasing predation rates.
Regarding the safety of birds, current research indicates that the chemicals sequestered by spotted lanternflies from Tree-of-Heaven are not lethal to avian predators. Although these compounds can cause a bitter taste and lead to birds regurgitating the insects, they do not cause serious injury or death. Care should be taken with control methods, as sticky traps used for lanternflies can inadvertently harm birds and other wildlife. Supporting healthy bird populations may contribute to localized control efforts, but it is not expected to halt the spread of widespread infestations independently.