There are some things that the SAV group at the University 
of Maryland put together; change in terms of atrazine, a herbi¬ 
cide, being used in the basin; variability in the Susquehanna 
River flow; some notions of sediment yield in the Patuxent River 
Basin being very possibly influenced by both construction acti¬ 
vities and practices through several decades; Hurricane Agnes, a 
natural event; fertilizer sales from Maryland; again, change in 
general practices; and sewage discharge from Washington. 
So what I'm saying here is that within the context of moni¬ 
toring characteristics of the Bay, there are important forcing 
functions, some of them natural, some of them man-influenced 
that are also changing. 
Monitoring programs, in our view, need to be able to sort 
out the natural variability, and I've given you some examples of 
that, from the types of change that is induced by human activi¬ 
ties. If we can't do that, then we have a real problem in con¬ 
tinuing to monitor. 
We also need to be able to detect and reasonably assign 
changes in habitat quality or water quality conditions to manage¬ 
ment activities. Again, we're interested in being able to — it 
seems necessary, rather — to be able to detect changes in 
inputs and then from soup to nuts, if you will, in the 
biological food web situation. 
And lastly, we need to be able to take some of these nice 
little patterns for monitoring, and as I said before and as I 
say again, be able to synthesize these various and sundry 
factors influencing the things we're concerned about in a way 
that's useful for the management community. 
Various people have showed some examples of monitoring; I 
wanted to show you a few more that have been going on in the Bay 
Region for a number of years. One of them, for example, is an 
anadromous fish survey that's been conducted since the early 
1950s. So there's some sense of continuity there. 
Another program of monitoring which has changed its form a 
bit over the years is that of submerged aquatic vegetation sam¬ 
pling. And it shows the pattern in sea grass abundance in the 
Upper Chesapeake Bay. 
As you know, and I'll show you explicitly in a few minutes, 
there's lots of different kinds of monitoring going on here. 
Some of it is of relevance to the Chesapeake Bay, but the moni¬ 
toring takes place in the Canadian Artie, as well as through the 
flyways. For example, a bit of synthesis in terms of monitoring 
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