Table 3 Number of food items and dietary niche width for Mute Swan, Bewick’s Swan and Whooper Swan in 20 February – 20 March and 21 March – 28 April
From: Ecological and phylogenetic aspects of the spring diet of three palaearctic species of swans
Mute Swan | Bewick's Swan | Whooper Swan | |
|---|---|---|---|
20 February – 20 March | |||
Number of food items | 12 | - | 10 |
Levins’ index (standardized value) | 2.42 (0.03) | - | 2.66 (0.04) |
21 March – 28 April | |||
Number of food items | 26 | 30 | 32 |
Levins’ index (standardized value) | 8.47 (0.16) | 6.11 (0.11) | 4.01 (0.06) |