In the last few decades research has focused on protecting wetlands and their ecological system services from invasive species. Cattails (Typha spp.) are an iconic species that shape wetland ecology by contributing to water filtration, preventing erosion, and providing nesting space for birds when native but invasive species can cause damage. In the Fraser River estuary Typha angustifolia has displaced native sedges and meadow species causing a decrease in biodiversity of the plant community and a decrease in ecological system services. The spread of T. angustifolia in North America began in the east coast of the US and Canada and has now expanded to the west coast. Wherever it appears, it may interbreed with the native species to produce a vigorous ecosystem-changing hybrid (Typha x glauca). However, no research had been conducted to see if T. x glauca is present in the Fraser River estuary. The goal of my research was to discover if T. x glauca was present in the Fraser River estuary and to test if it could be accurately identified by morphological traits. I used machine learning to analyze morphological measurements and microsatellites to examine genetic variation of samples from three wetland sites around Vancouver.
Results/Conclusions
The results showed the native species, the non-native and the hybrid are all present at each site. The hybrid was found to be intermediate for three of the morphological traits used in identification and displayed increased vigor, heterosis, for the other three traits. Microsatellite analysis supported putative field identifications based on morphology in all samples. Potential evidence of backcrossing between hybrids and parents were found which, given further investigation, could provide information on the timing of the invasion to the Fraser River Estuary. In summary, this data is the first evidence that T. angustifolia and the hybrid T. x glauca are present in the Fraser River Estuary as well as providing a multi-access key for identifying T. x glauca. This will allow individuals to accurately identify the hybrid without the need for genetic tools or a microscope to examine microscopic flower traits. In the future these traits can be used to decrypt this typically cryptic invasion by allowing for identification of the hybrid before it begins to cause major impacts on the estuary ecosystem.
