waders and their estuarine food supplies - Vlaams Instituut voor de ...

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PREY PROFITABILITY AND INTAKE RATE
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shell lengih (mm)
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prey weight (mg AFDW)
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Fig. 2. Handling time as a ttmctkin of A. prey length or B. prey weight in Mytilus opened by Oystercatchers suihbing the bill belween the
valves, or hammering ihe shell on the dorsal or ventral side. Sources: Blomert er«/. 11983), Cayford & Goss-Custard I 1990), Ens 11982), Pais
et al. (1996b). Hulscher (unpubl.). Koene (1978). Linders (1985). Meire & Ervynck (1986). Speakman (1984), Sutherland & Ens (1987).
Zwarts & Drent 11981). The three regression lines (sec also Table 11 differ significantly (p < 0.001) from each other according to cava iance
analyses: R- = 0.593 lor prey length and R- = 0.168 for the three techniques (loft); R- = 0.620 for prey w eight and R' = 0.100 for the three techniques
t right).
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prey weight (mg)
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Fig. 3. Handling lime as a function of A. prey lengih or B. prey weight in Cerastoderma. given separately for Oy stercatchers opening Cockles
by slabbing the bill between the valves or hammering the shell. Sources: Hulscher (1976 & unpubl.). Ens et al. (1996b & 1996c). Sutherland
(1982c). Swennen er al. (1989). Triplet (1994). The two regression lines iscc also Table I) differ significantly