Co-occurrence and commensal feeding between Little Egrets (Egretta garzetta) and Eurasian Spoonbills (Platalea leucorodia)

Hamza, F., & Selmi, S. (2016). Co-occurrence and commensal feeding between Little Egrets Egretta garzetta and Eurasian Spoonbills Platalea leucorodia. Bird Study 63: 509–515. doi: 10.1080/00063657.2016.1238035
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Abstract:

Capsule: The spatial distribution and feeding efficiency of Little Egrets Egretta garzetta wintering in the gulf of Gabès, Tunisia, are affected by a commensal association with the Eurasian Spoonbills Platalea leucorodia.

Aims: To investigate the role of the interspecific interaction between Little Egrets and Eurasian Spoonbills in shaping the spatial distribution and feeding efficiency of Little Egrets.

Methods: Using count and behavioural data, we examined the co-occurrence of these species in flocks, and compared the foraging efficiency of Little Egrets feeding with Eurasian Spoonbills with that of solitary Little Egrets.

Results: We found that the presence of Eurasian Spoonbills doubled the chance of Little Egrets being present. Within mixed flocks, the number of Little Egrets increased with the number of Spoonbills. Moreover, Little Egrets foraging in association with Eurasian Spoonbills took fewer steps, had higher pecking rates and higher prey intake rates than solitary Little Egrets.

Conclusion: Little Egrets appear to obtain foraging efficiency benefits by following Eurasian Spoonbills. This interaction seems to play a role in determining the spatial distribution of Little Egrets.

 

Eurasian Spoonbills (Platalea leucorodia), Gulf of Gabès, Tunisia (Csaba Pigniczki )

Eurasian Spoonbills (Platalea leucorodia), Gulf of Gabès, Tunisia (Csaba Pigniczki )