increasing anthropogenic stress from excessive nutrient loading, urbanization, shoreline 
modification, invasion of nonindigenous species, and the host of potential alterations 
resulting from global climate change. 
Sampling the range of vegetated and unvegetated tidal wetlands was not a 
simple endeavor but the approaches used in this survey, from use of hovercraft to 
quantifying burrowing shrimp, generally proved feasible for regional scale surveys of 
wetland condition. A slightly modified version of these approaches has since been used 
in another tidal wetland survey (Lee et al., 2006). This is not to say that improvements 
could not be made. 
In the sample design, with the exception of San Francisco Bay, sample sites 
were selected at random, with no attempt to require that sample sites fell within marsh 
habitats within a given multidensity category. The sample distribution by habitat type 
thus reflects the relative distribution of habitat types in the estuarine intertidal of the 
West Coast, but does mean that marsh type habitats had relatively few samples from 
some states. In hind sight, the habitat maps available appear to have been sufficiently 
accurate to have allowed partitioning of sample effort by habitat type. 
The use of the shoreline development indicator proved to be somewhat variable 
among field crews, suggesting a need for more careful a priori definition of shoreline 
development categories, and development of a photographic guide to assist field crews 
in providing a consistent classification. 
A difficult issue that arose was the need to subsample benthic samples due to 
the extreme processing time for some samples, especially those collected in vegetated 
wetlands. The consequence of this practice, which was carried out with differing 
subsample sizes by different state laboratories and contractors, was the generation of 
biological samples based on effectively different surface areas. We recommend that if 
at all possible, sufficient dollar and time resources be allocated to fully process the 0.1 
m 2 benthic samples regardless of the volume of residue. If that is not practical, then one 
possibility is to subsample all 0.1 m 2 benthic samples with a smaller core and process 
these independently. This approach would allow the comparison among all sites within 
a study using the smaller, standardized sample size, while maintaining the ability to 
compare the sites sampled with the 0.1 m 2 area with previous EMAP efforts. Another 
issue is the high abundance of oligochaetes and, to a lesser extent, insects in several 
tidal wetland habitats. Both of these are difficult taxa to identify, but to the extent 
practical they should be identified to species or at least to family. 
The other major ecological endpoints used in this survey were tidal wetland plant 
composition, cover, and biomass. One goal of the plant survey was to evaluate the 
potential for development of wetland indicators. However, one of the lessons learned is 
that the number of plant species in the 0.25 m 2 quadrat or 5-m transect is too low for 
use in most of the standard benthic indicators based on species richness. Another 
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