A Transportation Model Assessment of the Risk to Native Mussel Communities from Zebra Mussel Spread

Abstract

When introduced species threaten native flora and fauna, protection requires an analysis of the risk that native species face from the spread of the introduced species. Models of invading species, however, often do not include a dynamic component of risk. North American freshwater mussels are at risk of fouling by the introduced zebra mussel ( Dreissena polymorpha ). Predictions of the risk to native mussel communities of invasion by the zebra mussel can help prioritize conservation efforts. We present a model for the spatial analysis of zebra mussel spread that allows the characterization of relative risk of infestation to the high-quality mussel communities of Illinois streams. A gravity model, constrained at origin and destination, was parameterized with data on boat use at 120 boat landings in Illinois. The risk of spread of zebra mussels depends on the number of boat trips from infested waters, which in turn depends on distance from an infested water, boat use at a site, and the position of a lake within a river system. Habitats supporting a high diversity of native mussels and threatened and endangered species are at risk of infestation from reservoirs upstream. Invasion of inland lakes and reservoirs in Illinois is predicted to occur first at areas of high boat use close to currently infested waters, including the Fox Chain of Lakes, followed by central Illinois reservoirs. These reservoirs will act as stepping stones, facilitating the invasion of lakes upstream of critical native mussel habitats. Efforts to protect waters that center on prevention of the initial invasion of stepping-stone lakes could significantly reduce the risk of infestation. Education and inspection efforts are predicted to be more effective than quarantine because quarantines would displace boat traffic to critical habitats. The class of models presented here is useful for predicting risk of invasion when complete data on vector movement are not available.Evaluación de Riesgo de un Modelo de Transportación para Comunidades Nativas de Mejillones Debido a la Dispersión del Mejillon Zebra Resumen: Cuando las especies introducidas amenazan la flora y fauna nativa, la protecci ó n requiere de un análisis del riesgo que las especies nativas enfrentan debido a la disperción de las especies introducidas. Sin embargo, los modelos de invasi ó n de especies frecuentemente no incluyen un componente dinámico de riesgo. Los mejillones de Norteamérica se encuentran en riesgo de ser entampados por el mejill ó n zebra introducido ( Dreissena polymorpha ). Las predicciones de riesgo para las comunidades nativas de mejillones podrían ayudar a priorizar los efuerzos de conservación. Presentamos un modelo de análisis espacial de la dispersión del mejillón zebra que permite la caracterización del riesgo relativo de infestación de comunidades de mejillones de alta calidad de los arrollos de Illinois. Un modelo de gravedad, forzado en el origen y destino, se parametrizó con datos de uso de botes en 120 arribos en Illinois. El riesgo de dispersión del mejill...

Canal construction destroys the barrier between major European invasion lineages of the zebra mussel

“…This loss of overall genetic variability and the fact that populations of an invasion group are interconnected by linear structures like rivers, canals and reservoirs, explain the erosion of between-population structure. Long-distance transportation by boat traffic and massive downstream dispersal of free-swimming Dreissena larvae are assumed to have a significant effect (Koutnik & Padilla 1994;Horvath et al 1996;Schneider et al 1998). The significance and speed of the larval swamping was shown at the Main-Danube canal, where the overall water movement reflected the direction of genetic interchange.…”

Biological Invasions: Recommendations for U.S. Policy and Management

“…For instance, simple estimates of boat traffic to lakes are predictive of invasions even without knowing the exact propagule pressure, timing or frequency of introductions, or condition of the propagules (Schneider et al 1998, Bossenbroek et al 2001. Likewise, at the largest scale, estimates of international trade are positively correlated with invasions (Levine and D'Antonio 2003).…”

Boats, Pathways, and Aquatic Biological Invasions: Estimating Dispersal Potential with Gravity Models

“…Basically, doubly constrained gravity models require a substantial amount of information and are therefore limited to analyses of a relatively small number of lakes (e.g., Schneider et al 1998). In contrast, production-constrained gravity models can require as little information as lake size, location and numbers of registered boaters, and therefore can be applied to large systems.…”

“…However, past research have only used gravity models to describe the distribution of invasive species such as zebra mussels (Schneider et al 1998;Bossenbroek et al 2001) and the spiny water flea (MacIsaac et al in press), which are transported primarily by the recreational boater pathway (Johnson et al 2001). The efficacy of gravity models as an estimate of the actual mechanism -the movement pattern of recreational boaters -has not been explicitly examined, which is evident when the gravity model of Bossenbroek et al (2001) is examined more closely.…”