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 Survival Prospects for Wood Storks

 The three models developed by this study present

alternate ways of viewing the south Florida wetlands

ecosystem. Model I ignores the past, history of the area;

fish biomass expands and young birds are produced only as a

function of climatic conditions of the current year and

water stored from the previous year. Initial fish stock

and the number of potentially breeding birds are

unimportant. Models II and III consider climatic events

and production of preceding years; fish production is a

function not only of one year's sunlight and rainfall but

also of the fish stock surviving from the previous year.

In Model III bird production is a function not only of one

year's fish production but also of the fish production five

or more years previously, which determined the size of Fthe

current population of potentially breeding birds.

 According to analog simulations from Models I and II,

drainage narrows the period of time each year when it is

possible for the birds to carry out a successful nesting

effort. By narrowing this period, drainage makes the

timing of nesting more important, increases the risk of

winter rains disrupting nesting, and reduces the

possibility of second nestings, if the first should fail

(Figures 73 and 74). Drainage also reduces the number of

Wood Storks that are able to nest in a suitable breeding

year by reducing the absolute biomass of fish and the