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1 ISSN Russian Ornithological Journal 2014, Volume 23, Express Issue 976: Notes on the feeding behavior of the striped shrike Thamnophilus doliatus on Margarita Island (Caribbean Sea) A.G. Rezanov, A.A. Rezanov Alexander Gennadievich Rezanov, Andrey Alexandrovich Rezanov. Moscow City Pedagogical University, Institute of Natural Sciences, Department of Biology of Animals and Plants, st. Chechulina 1, Moscow, Russia, Received February 14, 2014 The striped shrike anttrap Thamnophilus doliatus (Linnaeus, 1764) (Thamnophilidae, Tyranni) is widespread in Central and South America (except for the southern half of the mainland). It is mainly an entomophage, collecting food mainly from leaves (foliage gleaning). In addition, these birds collect invertebrates from branches and trunks of trees and shrubs and on the ground (Hilty, Brown 1986, Keeler-Wolf 1986, Zimmer, Isler 2003, Koloff, Mennill 2011). In August 2011, in Venezuela, we observed striped shrike ant traps on the territory of the Hato El Sedral ranch (August 18) and on Margarita Island (Caribbean Sea, Leeward Islands, southern group of the Lesser Antilles archipelago) in August.A total of 3 birds (all males) were monitored: one in Ato El Sedral and two on Margarita Island. The total observation time was 4 hours. The main material on feeding behavior was collected on Margarita Island near Porlamar (Portofino hotel). Fig. 1. Forest belt on the border of the Portofino hotel (Margarita Island). August 20 Photo of the authors. Rus. ornithol. Journal Volume 23. Express Edition
2 Striped shrike anttraps fed in a narrow (no more than 10 m) forest belt (Fig. 1, 2), separating the hotel territory from a vast wasteland overgrown with weeds. In the forest belt, the main mass was made up of dense shrubs and leguminous trees (Fabaceae) towering above it with very large fruits, like those of Gleditsia. Terminalia guianensis also grew here, large trees with pear-shaped leaves. The birds examined shrubs and trees in the height layer from several tens of centimeters to 2-4 m (Fig. 3-6), sometimes they flew down and fed on the ground. Fig. 2. Forest belt on the border of the Portofino hotel (Margarita Island). August 22 Photo by the authors. Fig. 3. The striped shrike Thamnophilus doliatus examines the lower layer of legumes. Margarita Island. August 21 Photo of the authors. 706 Rus. ornithol. Journal Volume 23. Express Edition 976
Fig. 3 4. Male striped shrike anttrap Thamnophilus doliatus. Margarita Island. August 22 Photo by the authors. It is known that striped shrike ant traps can hunt small lizards (Keeler-Wolf 1986), however, despite the abundance of these reptiles (sometimes up to several individuals were in sight at the same time) in the forest belt, we did not note any attempts by ant traps to attack lizards or even just pay attention to them.Based on the observations of striped shrike ant traps, we identified the following feeding methods used by these birds: 1) Moving on the ground by jumping and pecking (picking up) food objects (small fruits) from the surface of the main substrate. 2) Inspection and collection of food from branches of trees and shrubs at a height of up to 2-4 m from the ground with the help of jumping and flipping, when jumping, the bird pulls its tail. 3) Inspection and collection of food from the leaves of the crown of a tree (bush) within a height of up to 2-4 m by jumping and flipping, when jumping, the bird pulls its tail. According to K.J. Zimmer, M.L. Isler (2003), striped shrike anttraps usually feed in a height layer of 0-3 m, up to a maximum of 10 m. 4) Inspection and collection of invertebrates from thin branches using "hanging" in the manner of tits. 5) Inspecting and collecting invertebrates from leaves using "hanging" in the manner of tits. 6) Walking and running along branches and inclined trunks (up to 60) and collecting invertebrates from the surface, along thin vertical branches of the ant - Rus. ornithol. Journal Volume 23. Express Edition
4 the dexterous moves easily both up and down, constantly scans the space around him. Fig. 5. The striped shrike Thamnophilus doliatus feeding. Margarita Island. August 20 Photo of the authors. Fig. 6. The striped shrike Thamnophilus doliatus feeding. Margarita Island. August 22 Photo by the authors. Fig. 7. The striped shrike Thamnophilus doliatus during feeding. Margarita Island. August 22 Photo by the authors. 708 Rus. ornithol. Journal Volume 23. Express Edition 976
