prevention measures include inspecting and washing boats and dumping live bait and bilge water 
onto land. Because of the possibility of spread by recreational boaters and anglers, education 
and outreach are also important prevention tools. The 100 th Meridian Initiative is one example 
of an interstate cooperative program that educates the public to prevent zebra mussel spread. 
This organization posts signs and brochures along highways and at boat ramps to teach the 
importance of cleaning and inspecting boats. Several states also have boat inspection sites, put 
out news releases, give presentations, educate divers, and train port of entry personnel. Missouri 
uses a variety of measures, such as installing Traveler Information Stations to advise boaters to 
clean their boats and working with bait shops to spread their message. 
Freshwater lakes and streams in the northern U.S. may be available for recreation for 
longer periods of the year because of increasing temperatures. This would, in turn, extend the 
period of time during which recreational boaters and anglers could disperse zebra mussels in the 
northern U.S. Educational efforts such as those undertaken by the 100 th Meridian Initiative may 
increase in importance, especially in the northern U.S. regions that are not yet infested with zebra 
mussels. 
While higher latitudes and altitudes in the U.S. and Canada may become more suitable 
for zebra mussel invasion, habitats at the southern extent of its range may become less suitable. 
As temperatures rise, so do metabolic rates in zebra mussels. Unlike some species, zebra 
mussels have little capacity for metabolic adjustment to temperature change (Alexander et al., 
1994). As turbidity increases, zebra mussel oxygen consumption drops, which may be due to 
increased undigestible particles clogging gills. Based on these results, Alexander et al. (1994) 
hypothesized that the most stressful conditions for zebra mussels would be high temperature and 
high turbidity conditions. Climate change may lead to these high temperature conditions in low 
altitude and latitude rivers and lakes in the U.S., making these habitats less suitable for zebra 
mussels; if these changes are combined with increased turbidity from altered precipitation and/or 
land use patterns, conditions may become too stressful for zebra mussels in these habitats. In 
addition, disturbances that result in die off of adults and decreased recruitment of 1-year old 
juveniles have been shown to stabilize zebra mussel populations (Strayer and Malcom, 2006). If 
changes in hydrology due to climate change include more intense flooding, this type of 
population stabilization that limits population size may occur more frequently, versus a more 
cyclic dynamic that can include very high densities. Management of more stable populations 
may be easier and impacts also may be more stable (Strayer and Malcom, 2006). 
2.5.2. Water Hyacinth 
Water hyacinth (Eichhornia crassipes ) is a tropical aquatic plant native to Brazil that has 
invaded many countries (Charudattan, 2001). Considered one of the most problematic weeds in 
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