Trafficsheds are defined by barriers that affect boat traffic. In the trafficsheds identified in Sarasota Bay, all are small enough that traffic within the trafficshed is negligible. When all the entry points to the trafficsheds can be identified, one can describe 100% of the boating activity in that trafficshed based on what passes through the entry/exit point by monitoring all of the entrances. When there is a single entrance, then a single observer at the entry point is sufficient to effectively monitor all boating activity for the trafficshed over the time period in question. When there is more than one entrance to the trafficshed, all entrances must be monitored- simulation results suggest that day-to-day traffic patterns (including types of boats, destinations selected, hence which exit is used) are highly variable even when factors such as weather, tide, and seasonality are constant. Presumably, one has no way of knowing at the beginning of the day which exit will receive what portion of the boat traffic.
The high variability in traffic patterns indicate that for smaller trafficsheds and shorter time periods, each day is unique and defies generalizations. Statistically valid inferences about the boat traffic of a single trafficshed can only be made in cases where the trafficshed is very large (allowing for a lot of observations) or when the trafficshed is observed for a long period of time. If boat traffic is as variable as the simulations suggest, one would have to be very cautious about making inferences on any of the trafficsheds in Sarasota Bay based on a single or a few days of monitoring efforts.
When one is gathering information about boat traffic, one is looking for information about what the long-term prospects of the area in consideration, as well as an indication of what extreme conditions one will be faced with. Extreme conditions can be monitored if one knows in advance when the extreme event is going to occur. For example, time of extreme traffic congestion are anticipated from long-term residents of the area, especially members of the business or law enforcement community who's livelyhoods are dependent on familiarity with boating behavior. If one knows that the heaviest traffic of the year occurs on Labor Day or the Fourth of July, then an observation effort on those days will be sufficient for measuring extreme traffic conditions. If one wishes to find typical conditions or long-time averages, it is very unlikely that one could gather sufficient information to describe these conditions based on a single day's observation effort.