Breeding takes place only when average bird weight rises

above a threshold value. In the model, breeding success of

one species, the Wood Stork is taken as an index not only

of the condition of the area's wading bird populations but

also of the general healthy functioning and overall

productivity of the wetlands system. The model tests the

effect of seasonal and long-term variations in rainfall and

the effect of drainage on expansion and contraction of

surface water area, fluctuation of the water table, total

annual fish production, fish density, and breeding success

of Wood Storks.


 Climate

 Figure 2 reveals seasonal and long-term patterns in

the rainfall of southwest Florida. The record of rainfall

is for the years 1951 through 1975 collected by ALICO

(Atlantic Land Improvement Company, La Belle) at Corkscrew

grove, a commercial orchard at latitude 260 25'N, located

30 km from the coast and immediately north of Corkscrew

Swamp (see Figure 4 for location). 5.

 Average yearly rainfall was 1421 mm at Corkscrew

grove, which is slightly greater than the 1372 mm average

reported by the U. S. Weather Bureau near the Gulf Coast at

Page Field in Ft. Myers, Lee County. On the average,

Corkscrew grove received 68% of its annual rain during the

5 mos from June through October.