Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels

Abstract: According to niche theory, sympatrically breeding species with similar diets frequently show foraging niche partitioning to decrease inter-specific competition, e.g. through temporal or spatial separation, or foraging specialisation. In this study, using stable isotope analyses, we aimed t...

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Main Authors: 3rd World Seabird Conference 2021, Ausems, Anne
Format: Article in Journal/Newspaper
Language:unknown
Published: Underline Science Inc. 2021
Subjects:
Online Access:https://dx.doi.org/10.48448/927x-7w84
https://underline.io/lecture/34638-sharing-menus-or-kids-specialsquestion-inter--and-intraspecific-differences-isotopic-niches-between-sympatrically-breeding-storm-petrels
id ftdatacite:10.48448/927x-7w84
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spelling ftdatacite:10.48448/927x-7w84 2023-05-15T13:56:43+02:00 Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels 3rd World Seabird Conference 2021 Ausems, Anne 2021 https://dx.doi.org/10.48448/927x-7w84 https://underline.io/lecture/34638-sharing-menus-or-kids-specialsquestion-inter--and-intraspecific-differences-isotopic-niches-between-sympatrically-breeding-storm-petrels unknown Underline Science Inc. Animal Biology Animal Science Ornithology MediaObject article Conference talk Audiovisual 2021 ftdatacite https://doi.org/10.48448/927x-7w84 2022-02-09T11:22:26Z Abstract: According to niche theory, sympatrically breeding species with similar diets frequently show foraging niche partitioning to decrease inter-specific competition, e.g. through temporal or spatial separation, or foraging specialisation. In this study, using stable isotope analyses, we aimed to assess the extent of niche overlap, differences in niche width and the relationship between isotopic signatures and chick growth in two sympatric storm-petrel species, Fregetta tropica (BBSP) and Oceanites oceanicus (WSP) breeding in Maritime Antarctica. We analysed δ15N and δ13C in chick down (pre-laying maternal diet), chick feathers (under tail coverts, UTC; current diet) and adult blood (current diet), and δ18O in UTC. We found isotopic (N, C) niche overlap (proportion (± confidence interval) of the standard ellipse area intersection relative to BBSP and WSP areas) for blood (BBSP 0.39 ± 0.18; WSP 0.10 ± 0.05) and down (BBSP 0.57 ± 0.19; WSP 0.26 ± 0.11), but a lack thereof for UTC (BBSP 0.05 ± 0.13; WSP 0.01 ± 0.03). We found wider isotopic niches for WSP compared to BBSP in all three tissues, indicating differences in foraging flexibility between the species. In both species body mass growth was negatively correlated with δ15N (in UTC for BBSP and in down for WSP). Tarsus growth was positively correlated with δ18O in WSP. We found no correlations for δ13C. The observed niche overlap between BBSP and WSP adults during the pre-breeding (down) and chick-rearing (blood) phases can be explained by their reliance on superabundant Antarctic krill (Euphausia superba). Despite similar chick growth rates in both species, BBSP chicks were fed a more nutritious diet, as implied by higher δ15N values, and the more frequent occurrence of fish in BBSP regurgitations reported in previous studies. While the highly productive Antarctic environment might reduce inter-specific foraging competition, chick nutrition requirements might force parents to be more selective in chick prey selection. Authors: Anne Ausems¹, Grzegorz Skrzypek², Katarzyna Wojczulanis - Jakubas¹, Dariusz Jakubas¹ ¹University of Gdansk, ²The University of Western Australia (M090) Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Antarctica Euphausia superba DataCite Metadata Store (German National Library of Science and Technology) Antarctic
institution Open Polar
collection DataCite Metadata Store (German National Library of Science and Technology)
op_collection_id ftdatacite
language unknown
topic Animal Biology
Animal Science
Ornithology
spellingShingle Animal Biology
Animal Science
Ornithology
3rd World Seabird Conference 2021
Ausems, Anne
Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
topic_facet Animal Biology
Animal Science
Ornithology
description Abstract: According to niche theory, sympatrically breeding species with similar diets frequently show foraging niche partitioning to decrease inter-specific competition, e.g. through temporal or spatial separation, or foraging specialisation. In this study, using stable isotope analyses, we aimed to assess the extent of niche overlap, differences in niche width and the relationship between isotopic signatures and chick growth in two sympatric storm-petrel species, Fregetta tropica (BBSP) and Oceanites oceanicus (WSP) breeding in Maritime Antarctica. We analysed δ15N and δ13C in chick down (pre-laying maternal diet), chick feathers (under tail coverts, UTC; current diet) and adult blood (current diet), and δ18O in UTC. We found isotopic (N, C) niche overlap (proportion (± confidence interval) of the standard ellipse area intersection relative to BBSP and WSP areas) for blood (BBSP 0.39 ± 0.18; WSP 0.10 ± 0.05) and down (BBSP 0.57 ± 0.19; WSP 0.26 ± 0.11), but a lack thereof for UTC (BBSP 0.05 ± 0.13; WSP 0.01 ± 0.03). We found wider isotopic niches for WSP compared to BBSP in all three tissues, indicating differences in foraging flexibility between the species. In both species body mass growth was negatively correlated with δ15N (in UTC for BBSP and in down for WSP). Tarsus growth was positively correlated with δ18O in WSP. We found no correlations for δ13C. The observed niche overlap between BBSP and WSP adults during the pre-breeding (down) and chick-rearing (blood) phases can be explained by their reliance on superabundant Antarctic krill (Euphausia superba). Despite similar chick growth rates in both species, BBSP chicks were fed a more nutritious diet, as implied by higher δ15N values, and the more frequent occurrence of fish in BBSP regurgitations reported in previous studies. While the highly productive Antarctic environment might reduce inter-specific foraging competition, chick nutrition requirements might force parents to be more selective in chick prey selection. Authors: Anne Ausems¹, Grzegorz Skrzypek², Katarzyna Wojczulanis - Jakubas¹, Dariusz Jakubas¹ ¹University of Gdansk, ²The University of Western Australia (M090)
format Article in Journal/Newspaper
author 3rd World Seabird Conference 2021
Ausems, Anne
author_facet 3rd World Seabird Conference 2021
Ausems, Anne
author_sort 3rd World Seabird Conference 2021
title Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
title_short Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
title_full Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
title_fullStr Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
title_full_unstemmed Sharing menus or kids specials? Inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
title_sort sharing menus or kids specials? inter- and intraspecific differences isotopic niches between sympatrically breeding storm-petrels
publisher Underline Science Inc.
publishDate 2021
url https://dx.doi.org/10.48448/927x-7w84
https://underline.io/lecture/34638-sharing-menus-or-kids-specialsquestion-inter--and-intraspecific-differences-isotopic-niches-between-sympatrically-breeding-storm-petrels
geographic Antarctic
geographic_facet Antarctic
genre Antarc*
Antarctic
Antarctic Krill
Antarctica
Euphausia superba
genre_facet Antarc*
Antarctic
Antarctic Krill
Antarctica
Euphausia superba
op_doi https://doi.org/10.48448/927x-7w84
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