Attributes / relations provided by
♦ 1del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.).
Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
♦ 2Diet composition and prey choice by the red-backed shrike Lanius collurio in western Poland, Piotr Tryjanowski, Malgorzata Karolina Karg, Jerzy Karg, Belg. J. Zool., 133 (2) : 157-162 (2003)