Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms

Detalhes bibliográficos
Autor(a) principal: Carreira, Bruno Martins, 1987-
Data de Publicação: 2016
Idioma: eng
Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
Texto Completo: http://hdl.handle.net/10451/27182
Resumo: Tese de doutoramento, Biologia (Ecologia), Universidade de Lisboa, Faculdade de Ciências, 2016
id RCAP_c65ac0fbc6a60a0bd70abd8e8f9909d5
oai_identifier_str oai:repositorio.ulisboa.pt:10451/27182
network_acronym_str RCAP
network_name_str Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
repository_id_str https://opendoar.ac.uk/repository/7160
spelling Warm vegetarians? : heat wave effects on aquatic omnivorous ectothermsTeses de doutoramento - 2016Domínio/Área Científica::Ciências Naturais::Ciências BiológicasTese de doutoramento, Biologia (Ecologia), Universidade de Lisboa, Faculdade de Ciências, 2016Freshwater communities are particularly vulnerable to climate change, as they are mainly composed of ectotherm species, whose metabolism is strongly influenced by temperature. This relationship is particularly relevant, as projections show both a global warming and an increase in the frequency, intensity and duration of extreme climatic events such as heat waves. Measurements of imbalanced temperature effects on various metabolic aspects of ectotherms lead to the suggestion that these organisms may optimize energetic intake at higher temperatures by increasing herbivory and avoiding protein-rich animal diets. In this thesis, I tested the effects of different types of heat waves on diet assimilation (and indirectly on diet choice) of five species of freshwater omnivorous ectotherms, belonging to three different phyla. As study models, I used species commonly found in Mediterranean temporary ponds: the tadpoles of three anuran species breeding along a seasonal climatic gradient (Discoglossus galganoi, Hyla arborea and Hyla meridionalis), the gastropod Radix balthica and the invasive crayfish Procambarus clarkii. Individuals were fed animal, plant or mixed diets and exposed to temperature treatments simulating the current short heat waves, as well as long heat waves expected to become more frequent in the future. Treatment responses were recorded in terms of survival and life history traits. In the individuals feeding on the mixed diet, the proportion of animal and plant material assimilated was estimated with stable isotopes. Overall, I found evidence that performance at higher temperatures decreased on animal diets and increased on plant diets, suggesting that diet quality changed with temperature. Although the type of heat wave inducing assimilation shifts varied and the species responded to different extents, heat waves generally increased the assimilation of plant material, and this was adaptive in almost all species. Furthermore, the seasonal climatic gradient in the three anuran species was found to match a gradient in their feeding preferences, the degree of herbivory increasing with minimum temperature experienced in nature. Surprisingly, albeit native to climates warmer than the Iberian Peninsula, the invasive crayfish P. clarkii was negatively affected by the heat waves. However, the results of nutrient assimilation showed that warmer temperatures may increase this species’ impact in freshwater communities through increased herbivory. In conclusion, my results suggest that temperature plays an important role in modulating nutrient acquisition in omnivorous ectotherms. A greater assimilation of plant material or increased herbivory may help ectotherms to cope with the challenges imposed by higher temperatures. However, a reduction in the trophic positions of the omnivores may trigger changes in the functioning and structure of freshwater communities and food webs.Rebelo, Rui Miguel Borges Sampaio e, 1969-Laurila, AnssiRepositório da Universidade de LisboaCarreira, Bruno Martins, 1987-2017-03-10T17:12:53Z201620162016-01-01T00:00:00Zdoctoral thesisinfo:eu-repo/semantics/publishedVersionapplication/pdfhttp://hdl.handle.net/10451/27182TID:101439970enginfo:eu-repo/semantics/openAccessreponame:Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)instname:FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologiainstacron:RCAAP2025-03-17T13:37:45Zoai:repositorio.ulisboa.pt:10451/27182Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireinfo@rcaap.ptopendoar:https://opendoar.ac.uk/repository/71602025-05-29T02:49:45.204238Repositórios Científicos de Acesso Aberto de Portugal (RCAAP) - FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologiafalse
dc.title.none.fl_str_mv Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
title Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
spellingShingle Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
Carreira, Bruno Martins, 1987-
Teses de doutoramento - 2016
Domínio/Área Científica::Ciências Naturais::Ciências Biológicas
title_short Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
title_full Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
title_fullStr Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
title_full_unstemmed Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
title_sort Warm vegetarians? : heat wave effects on aquatic omnivorous ectotherms
author Carreira, Bruno Martins, 1987-
author_facet Carreira, Bruno Martins, 1987-
author_role author
dc.contributor.none.fl_str_mv Rebelo, Rui Miguel Borges Sampaio e, 1969-
Laurila, Anssi
Repositório da Universidade de Lisboa
dc.contributor.author.fl_str_mv Carreira, Bruno Martins, 1987-
dc.subject.por.fl_str_mv Teses de doutoramento - 2016
Domínio/Área Científica::Ciências Naturais::Ciências Biológicas
topic Teses de doutoramento - 2016
Domínio/Área Científica::Ciências Naturais::Ciências Biológicas
description Tese de doutoramento, Biologia (Ecologia), Universidade de Lisboa, Faculdade de Ciências, 2016
publishDate 2016
dc.date.none.fl_str_mv 2016
2016
2016-01-01T00:00:00Z
2017-03-10T17:12:53Z
dc.type.driver.fl_str_mv doctoral thesis
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://hdl.handle.net/10451/27182
TID:101439970
url http://hdl.handle.net/10451/27182
identifier_str_mv TID:101439970
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
instname:FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
instacron:RCAAP
instname_str FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
instacron_str RCAAP
institution RCAAP
reponame_str Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
collection Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
repository.name.fl_str_mv Repositórios Científicos de Acesso Aberto de Portugal (RCAAP) - FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
repository.mail.fl_str_mv info@rcaap.pt
_version_ 1833601496693866496