DOI: 10.5061/dryad.18931zd98
title: Data from: Association of nesting <em>Otus scops</em> (Eurasian Scops Owl) with <em>Xerotyphlops vermicularis</em> (Worm snake) in Türkiye

description: We report the discovery of a novel relationship between the Eurasian Scops
 Owl (Otus scops) and the Worm Snake (Xerotyphlops vermicularis) found
 during systematic nest box inspections spanning six breeding seasons in
 central Türkiye. The presence of live Worm Snakes was specific only to
 nest boxes occupied by Eurasian Scops Owls, which delivered snakes alive
 to the nest boxes. The snakes were found in 44% of 109 owl nests. While
 there was no significant difference in clutch or brood size between nests
 with and without snakes, the presence of snakes in the nest significantly
 improved the survival rate of owl nestlings, from 29% to 61% in nests
 without and with snakes, respectively. Insectivorous snakes were found
 both on and within the nesting material, where they might remove commensal
 and kleptoparasitic insects, e.g., ants and fly larvae. Several research
 questions emerge from our findings, since non-consumptive interaction
 between blind snakes and owls is now known from different parts of the
 globe. Taken together, these studies suggest that behaviors potentially
 involving cognitive processes could, over evolutionary timescales,
 facilitate the emergence of mutualistic interactions through selective
 predation. Owl nests might be beneficial environments for the
 insectivorous Worm Snake, but it remains to be determined whether
 owl-snake interactions are a facultative mutualistic relationship or only
 misdirected predation or even parasitism, primarily beneficial just for
 the owls.
description: ## Data from: Association of nesting *Otus scops* (Eurasian Scops Owl)
 with *Xerotyphlops vermicularis* (Worm snake) in Türkiye #### Dataset
 description This dataset was collected between 2017 and 2022 in Türkiye as
 part of a long-term nest box monitoring study of the Otus scops (Eurasian
 Scops Owl). **File format** File name: data-owl-snake.xlsx File type:
 Microsoft Excel (.xlsx) Sheets: “without snake”, “with snake” The dataset
 contains two separate sheets: * Without snake – Data from nests without
 Worm Snakes. - With snake – Data from nests where Worm Snakes were found.
 **Column descriptions** Shared columns (in both sheets): * Nest no. – nest
 box identification number. - Year – Year of breeding attempt. * Eggs laid
 – Total number of eggs laid. - Eggs date – Date of first egg laid. * Egg
 Julian – Julian day of the first egg laid. - Hatched – Number of eggs
 hatched. * Hatched date – Date of first young hatching. - Hatch Julian –
 Julian day of first young hatching. * Fledged – Number of young fledged. -
 Fledged date – Date of first fledgling leaving the nest. * Fledge Julian –
 Julian day of first fledgling leaving the nest. - Success rate –
 Fledged/Hatched. * Survival rate – Hatched/Eggs Snake number – Number of
 Xerotyphlops vermicularis individuals detected in the nest. **Additional
 columns:** (only in the “with snake” sheet): First snake date – Date of
 the first Worm Snake observed in the nest. First snake Julian – Julian day
 of the first Worm Snake observed. **Usage notes:** All data were collected
 directly during field monitoring. Missing (empty cells) values are coded
 as NA. All dates are given both in calendar format (day/month) and in
 Julian day format.