학술논문

The identification of watermilfoil, discovery of hybrid watermilfoil, and their implications for aquatic plant management in the Clark Fork River, Western MT, USA
Document Type
article
Source
Journal of Freshwater Ecology, Vol 36, Iss 1, Pp 111-125 (2021)
Subject
myriophyllum spicatum
myriophyllum sibiricum
eurasian watermilfoil
northern watermilfoil
invasive species
macrophyte
reservoir
aquatic plant management
Environmental sciences
GE1-350
Ecology
QH540-549.5
Language
English
ISSN
0270-5060
2156-6941
02705060
Abstract
Eurasian watermilfoil (Myriophyllum spicatum) is an invasive submersed macrophyte that has infested many waters in North America since its introduction. Eurasian watermilfoil has the ability to alter the structure and function of the ecosystems that it invades. Eurasian watermilfoil was first surveyed in the Clark Fork River, MT in 2008, alongside the native northern watermilfoil (Myriophyllum sibiricum). Three reservoirs (Cabinet Gorge, Noxon Rapids and Thompson Falls) on the lower Clark Fork River had entire lake surveys conducted using the point intercept method. Morphological data from these surveys showed that only Eurasian watermilfoil and northern watermilfoil were present during the time of the surveys in 2008. The results of the morphological identification were supported by molecular identification at three different laboratories. In 2015, a genetic survey of watermilfoil species was conducted on the Noxon Rapids Reservoir and found that hybrid watermilfoil (Myriophyllum spicatum × sibiricum) was present. This hybridization event poses a number of issues for aquatic plant management. Hybrid watermilfoil is much more difficult to identify morphologically than its parent types. The hybrid is also more invasive and may be differentially susceptible to some herbicides than the parental type Eurasian watermilfoil.