Martín Alejandro Colombo, Adrián Jauregui, Luciano N. Segura
{"title":"Weather influenced nestling growth of an insectivorous but not a granivorous grassland passerine in Argentina","authors":"Martín Alejandro Colombo, Adrián Jauregui, Luciano N. Segura","doi":"10.1016/j.avrs.2024.100173","DOIUrl":null,"url":null,"abstract":"<div><p>Nestling growth of birds can be affected by weather fluctuations. In general, it is expected that higher temperatures favor growth by improving food availability and nestling metabolism, while rain hinders it by reducing foraging efficiency. However, most of these patterns have been described in insectivorous cavity-nesting birds in temperate forests. We tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to weather. We measured nestlings of the Hellmayr's Pipit (<em>Anthus hellmayri</em>, an insectivorous passerine) and the Grassland Yellow-Finch (<em>Sicalis luteola</em>, which feeds its nestlings exclusively with seeds) during three breeding seasons (2017–2020) in central-eastern Argentina. We took measurements of tarsus and body mass, modeled growth curves using nonlinear mixed-effects models, and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to hatching. For pipits (60 nestlings from 21 nests), minimum temperatures during the growth period were positively associated with tarsus and body mass asymptotes. Also, there was a positive association between precipitation during the pre-hatching period and tarsus asymptote. Conversely, none of the weather variables analyzed had significant effects on nestling growth of finches (131 nestlings from 35 nests). Dietary contrast between species may explain the different results. Arthropod activity and abundance can be affected by weather variations within the span of a breeding season, whereas seeds may depend on conditions from previous years, making the effects harder to detect. Fledglings with reduced asymptotic size can have reduced chances of survival. Hence, pipit populations could be impacted if they experience cold and dry conditions during their breeding season, which is of major relevance in the current context of climate change.</p></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"15 ","pages":"Article 100173"},"PeriodicalIF":1.6000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2053716624000161/pdfft?md5=a1f77d04f73927201ab5e13e09f91454&pid=1-s2.0-S2053716624000161-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Avian Research","FirstCategoryId":"99","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2053716624000161","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ORNITHOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Nestling growth of birds can be affected by weather fluctuations. In general, it is expected that higher temperatures favor growth by improving food availability and nestling metabolism, while rain hinders it by reducing foraging efficiency. However, most of these patterns have been described in insectivorous cavity-nesting birds in temperate forests. We tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to weather. We measured nestlings of the Hellmayr's Pipit (Anthus hellmayri, an insectivorous passerine) and the Grassland Yellow-Finch (Sicalis luteola, which feeds its nestlings exclusively with seeds) during three breeding seasons (2017–2020) in central-eastern Argentina. We took measurements of tarsus and body mass, modeled growth curves using nonlinear mixed-effects models, and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to hatching. For pipits (60 nestlings from 21 nests), minimum temperatures during the growth period were positively associated with tarsus and body mass asymptotes. Also, there was a positive association between precipitation during the pre-hatching period and tarsus asymptote. Conversely, none of the weather variables analyzed had significant effects on nestling growth of finches (131 nestlings from 35 nests). Dietary contrast between species may explain the different results. Arthropod activity and abundance can be affected by weather variations within the span of a breeding season, whereas seeds may depend on conditions from previous years, making the effects harder to detect. Fledglings with reduced asymptotic size can have reduced chances of survival. Hence, pipit populations could be impacted if they experience cold and dry conditions during their breeding season, which is of major relevance in the current context of climate change.
期刊介绍:
Avian Research is an open access, peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world. It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists. As an open access journal, Avian Research provides a unique opportunity to publish high quality contents that will be internationally accessible to any reader at no cost.