Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status

Transitional waters are highly productive ecosystems, providing essential goods and services to the biosphere and human population. Human influence in coastal areas exposes these ecosystems to continuous internal and external disturbance. Nitrogen-loads can affect the composition of the resident com...

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Main Authors: Simona Sporta Caputi, Giulio Careddu, Edoardo Calizza, Federico Fiorentino, Deborah Maccapan, Loreto Rossi, Maria Letizia Costantini
Format: Article
Language:English
Published: MDPI AG 2020-04-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/10/8/2756
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author Simona Sporta Caputi
Giulio Careddu
Edoardo Calizza
Federico Fiorentino
Deborah Maccapan
Loreto Rossi
Maria Letizia Costantini
author_facet Simona Sporta Caputi
Giulio Careddu
Edoardo Calizza
Federico Fiorentino
Deborah Maccapan
Loreto Rossi
Maria Letizia Costantini
author_sort Simona Sporta Caputi
collection DOAJ
description Transitional waters are highly productive ecosystems, providing essential goods and services to the biosphere and human population. Human influence in coastal areas exposes these ecosystems to continuous internal and external disturbance. Nitrogen-loads can affect the composition of the resident community and the trophic relationships between and within species, including fish. Based on carbon (δ<sup>13</sup>C) and nitrogen (δ<sup>15</sup>N) stable isotope analyses of individuals, we explored the feeding behaviour of two ecologically and economically important omnivorous fish, the eel <i>Anguilla anguilla</i> and the seabream <i>Diplodus annularis</i>, in three neighbouring lakes characterised by different trophic conditions. We found that <i>A. anguilla</i> showed greater generalism in the eutrophic lake due to the increased contribution of basal resources and invertebrates to its diet. By contrast, the diet of <i>D. annularis,</i> which was mainly based on invertebrate species, became more specialised, focusing especially on polychaetes. Our results suggest that changes in macroinvertebrate and fish community composition, coupled with anthropogenic pressure, affect the trophic strategies of high trophic level consumers such as <i>A. anguilla</i> and <i>D. annularis</i>. Detailed food web descriptions based on the feeding choices of isotopic trophospecies (here Isotopic Trophic Units, ITUs) enable identification of the prey taxa crucial for the persistence of omnivorous fish stocks, thus providing useful information for their management and habitat conservation.
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spelling doaj.art-e1ef69217b3d4d6f9f9d5487788740d02023-11-19T21:47:51ZengMDPI AGApplied Sciences2076-34172020-04-01108275610.3390/app10082756Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic StatusSimona Sporta Caputi0Giulio Careddu1Edoardo Calizza2Federico Fiorentino3Deborah Maccapan4Loreto Rossi5Maria Letizia Costantini6Department of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyDepartment of Environmental Biology, Sapienza University of Rome, via dei Sardi 70, 00185 Rome, ItalyTransitional waters are highly productive ecosystems, providing essential goods and services to the biosphere and human population. Human influence in coastal areas exposes these ecosystems to continuous internal and external disturbance. Nitrogen-loads can affect the composition of the resident community and the trophic relationships between and within species, including fish. Based on carbon (δ<sup>13</sup>C) and nitrogen (δ<sup>15</sup>N) stable isotope analyses of individuals, we explored the feeding behaviour of two ecologically and economically important omnivorous fish, the eel <i>Anguilla anguilla</i> and the seabream <i>Diplodus annularis</i>, in three neighbouring lakes characterised by different trophic conditions. We found that <i>A. anguilla</i> showed greater generalism in the eutrophic lake due to the increased contribution of basal resources and invertebrates to its diet. By contrast, the diet of <i>D. annularis,</i> which was mainly based on invertebrate species, became more specialised, focusing especially on polychaetes. Our results suggest that changes in macroinvertebrate and fish community composition, coupled with anthropogenic pressure, affect the trophic strategies of high trophic level consumers such as <i>A. anguilla</i> and <i>D. annularis</i>. Detailed food web descriptions based on the feeding choices of isotopic trophospecies (here Isotopic Trophic Units, ITUs) enable identification of the prey taxa crucial for the persistence of omnivorous fish stocks, thus providing useful information for their management and habitat conservation.https://www.mdpi.com/2076-3417/10/8/2756food websMediterranean coastal lakesnitrogen pollutionstable isotopestrophic relationships<i>Anguilla anguilla</i>
spellingShingle Simona Sporta Caputi
Giulio Careddu
Edoardo Calizza
Federico Fiorentino
Deborah Maccapan
Loreto Rossi
Maria Letizia Costantini
Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
Applied Sciences
food webs
Mediterranean coastal lakes
nitrogen pollution
stable isotopes
trophic relationships
<i>Anguilla anguilla</i>
title Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
title_full Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
title_fullStr Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
title_full_unstemmed Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
title_short Changing Isotopic Food Webs of Two Economically Important Fish in Mediterranean Coastal Lakes with Different Trophic Status
title_sort changing isotopic food webs of two economically important fish in mediterranean coastal lakes with different trophic status
topic food webs
Mediterranean coastal lakes
nitrogen pollution
stable isotopes
trophic relationships
<i>Anguilla anguilla</i>
url https://www.mdpi.com/2076-3417/10/8/2756
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AT federicofiorentino changingisotopicfoodwebsoftwoeconomicallyimportantfishinmediterraneancoastallakeswithdifferenttrophicstatus
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