conditions, how one species uses another as 

 cover or food or habitat for reproduction. 



• We can't predict how the dynamics of 

 various populations will change in new 

 surroundings; we don't have enough long- 

 term data to know how variable populations 

 can be and still persist in perpetuity. It is 

 unrealistic to expect stability once a habitat 

 is constructed. 



• We don't know what factors confer 

 resilience to species and communities. 

 Pickleweed is a good invader after some 

 disturbances and persists well under a 

 variety of other disturbances. Tolerance to a 

 wide range of salinities and inundation 

 regimes appears to be important to 

 pickleweed's resilience, but we have minimal 

 understanding of why other species are less 

 resilient. 



• There have been few studies of 

 constructed wetlands to allow us to predict the 

 kinds of problems that will arise during 

 construction. 



None of these problems or shortcomings 

 should halt efforts to restore ecosystems. 

 Rather, the past experiences should be used to 

 guide future restoration programs. 

 Unexpected problems will occur, and a 

 mechanism for dealing with those problems 

 must be in place. Every site can be used to 

 improve our ability to restore wetlands. 

 Monitoring has a very important role in the 

 implementation of restoration projects, but it 

 should be linked to research programs and not 

 just be a number-gathering process. 



Most importantly, the problems must be 

 acknowledged; in other words, just because a 

 restoration design has been developed does not 

 mean that the project will achieve it. Just 

 because channels are excavated to the proper 

 elevations does not mean they won't fill in or 

 erode. Just because a transplanting program 

 provides the desired species does not mean the 

 vegetation will persist or that it will attract 

 the desired animals. 



The adaptive management program for 

 Tijuana Estuary is the proper approach, and 

 it should become the standard for all future 

 restoration programs in the region. 



139 



