Hydro-ecological relations in the Delta Waters

In order to lsok for relatiouehips between prey and bird abundance and
to cry to understand the distribution described abmve, the density of
each bird group was calculated (the wan of the 12 average monthly
c m s of the period 1975/76 - 1983184 was used). For each group the
surfaces of t4e follwing habitats (for the tidal and stagnant basfns
respeetlvely) were u ~ s t calculate o the density: pi8civores: tidal
water and tidal areas er deep and &allow warer; waders: tidal flats or
shores; 6iVing ducks: tidal wata and tidal ateas or deep a4ld shallow
water; herbivores: sale marshes and adjacent wetlands ar $here6 aad
shallow water. Of course this is a very crude approximation hut for
such a large scale comparison no greater detidl can he used.
Table 2 Winter density (N/1000 me) of Gobiid fish and densities of
Piseivores (h11100 ha) in the different aquatic s$stems of the
Delta arm. (Source of fish data: Cl) Ewrlynck (pen. mm.)
(2) Bamerlynck, et al. (in press) (3) Dopmhos and Tviek.
L987 (4) Waacdenburg and Meyer, 1988) (Voordelta (W);
Westerscbelde (TB); Oosterschelde (05); rame er-Volkerak
(KV); kevelinaen Meer (CH); Veerse Mser (W); Baringvliet
(W); Bollaads Ddep (!.DJ; Biesbosch (BB)]
Fish
Bird
Basin Density Seurce Density
(~11000 m*)
(e/ioo ha)