launching sites, regularly patrol waters and roads, and enforce violations such as launching a 
boat or transporting a vehicle on public roads with plants attached. 
Prevention activities typically focus on species that are already known to cause impacts. 
Climate change, however, may enhance environmental conditions for some species with the 
following consequences: (1) new species are now able to survive in these locations, (2) known 
invasive species expand their range into new territories, and (3) species that are currently not 
considered invasive may become invasive and cause significant impacts. Monitoring and survey 
efforts may be used to identify species that are encroaching as a result of expanding ranges. 
Monitoring efforts, as given in Figure 1-1, may need to be modified to focus on weakened or 
changing ecosystems that are more vulnerable to invasion (Hellmann et al., 2008). As 
temperatures warm, precipitation regimes fluctuate, and nutrient flows change, ecosystems may 
lose their ability to support a diverse set of native species, becoming more vulnerable to invasion 
as new resources become available; however, managers should not assume that pristine, species- 
rich environments are immune to invasion (Melbourne et al., 2007; Byers and Noonburg, 2003; 
Davis et al., 2000). 
Vectors also may be influenced by changes in climate and should be evaluated for their 
ability to transmit species under changing conditions. For example, seaways may remain open 
for longer periods during the year due to warming temperatures; thus, shipping and boating 
traffic, a major vector for species such as the zebra mussel, also may increase. In addition, 
completely new shipping routes may also open in polar waters due to melting ice, which will 
further increase boating and shipping traffic (Hellmann et al., 2008; Pyke et al., 2008). To begin 
to address these concerns, pathway analysis and species prediction models should be modified to 
include climate change parameters. States may need to alert inspection and border control 
agencies to new invasive threats, and related inspection priorities may need to be re-assessed in 
light of these impending threats and pathways. Import/introduction/release requirements should 
be based on risk assessments that account for how changing conditions will affect the potential 
for an area to be invaded. Climate changes resulting in increased storm surge and flooding may 
increase the risk of species escape from aquaculture facilities. In light of these changes, 
aquaculture facilities may need to take additional precautionary measures against escapes or 
establishment (e.g., use only triploids, stock only one sex, or use sterile hybrids) or to use only 
native species. Finally, ongoing land and water management activities should be re-evaluated 
for their potential to provide new invasion pathways. For example, waterway engineers could 
examine passage between water bodies that were historically separated, create barriers to 
passages, and consider AIS spread before re-filling or reconnecting waterways (Rahel and Olden, 
2008). 
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