The belief that opossums consume a large number of ticks each year has gained considerable traction among the public. Many people consider these unique marsupials to be a natural solution for tick control in their environments. This widespread idea suggests that opossums play a significant role in reducing the presence of these disease-carrying parasites. Exploring the factual basis behind this popular claim helps to understand the true relationship between opossums and ticks.
The Widespread Belief and Its Origins
The popular notion that a single opossum can eliminate thousands of ticks annually, often cited as 5,000 to 6,000 per season or even per week, is widely circulated. This widespread belief largely stems from a 2009 study conducted by the Cary Institute of Ecosystem Studies. Researchers in this initial study placed captive opossums in enclosed spaces with larval ticks. The study observed that a large percentage of ticks introduced did not drop off the opossums. Based on this observation, it was extrapolated that the opossums must have consumed the ticks during their grooming activities. This extrapolation led to the impressive figures often quoted regarding the number of ticks an opossum supposedly eats.
Scientific Research on Possum Tick Consumption
More recent scientific investigations have provided a different perspective on the actual number of ticks opossums consume. A 2021 study, conducted by Cecilia Hennessy and Kaitlyn Hild, directly challenged the earlier assumptions. This research involved a detailed analysis of the stomach contents from 32 wild Virginia opossums collected in central Illinois. The examination of these wild opossum stomachs revealed no evidence of ticks or tick parts.
Furthermore, the researchers conducted an extensive review of 23 other published studies on the diets of Virginia opossums, including analyses of stomach contents and scat. None of these prior studies reported finding ticks in the opossums’ digestive systems. These findings collectively suggest that ticks are not a regular or preferred food source for wild Virginia opossums. The discrepancy with earlier findings may be due to the behavior of captive animals differing from those in the wild, and the prior assumption that absent ticks were consumed rather than simply falling off unnoticed.
Possums’ Broader Interaction with Ticks
While recent scientific evidence does not support opossums devouring thousands of ticks, their interaction with ticks is still noteworthy. Opossums are known for their fastidious grooming habits, similar to cats. This diligent self-cleaning removes ticks from their fur. However, the ticks removed through grooming are often simply killed or dislodged, rather than intentionally ingested as a food source.
Despite the popular belief, opossums can still carry ticks, sometimes in large numbers, including black-legged ticks which are known vectors for Lyme disease. It is worth noting that opossums possess a resistance to diseases like Lyme disease and rabies, possibly due to their lower body temperature and immune system.
Opossums are opportunistic omnivores with a varied diet that includes insects, fruits, carrion, and small vertebrates. Their presence in an ecosystem does not appear to significantly reduce local tick populations. Attracting opossums to residential areas specifically for tick control may not yield the desired results and could inadvertently attract other wildlife.