Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea
Severe reproductive failure has contributed to a drastic population decline of the nominate Lesser Black-backed Gull (Larus fuscus fuscus) in its breeding grounds in the Gulf of Finland and the Bay of Bothnia. In intensive field studies in the central area of the Gulf of Finland, roughly 65-70% of c...
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fttsvojs:oai:journal.fi:article/133758 2023-09-05T13:20:56+02:00 Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea Hario, M. Nuutinen, J. M. J. 2011-03-31 application/pdf https://ornisfennica.journal.fi/article/view/133758 eng eng BirdLife Finland https://ornisfennica.journal.fi/article/view/133758/82308 https://ornisfennica.journal.fi/article/view/133758 Ornis Fennica; Vol 88 Nro 1 (2011); 1–13 Ornis Fennica; Vol. 88 No. 1 (2011); 1–13 0030-5685 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article 2011 fttsvojs 2023-08-23T23:03:06Z Severe reproductive failure has contributed to a drastic population decline of the nominate Lesser Black-backed Gull (Larus fuscus fuscus) in its breeding grounds in the Gulf of Finland and the Bay of Bothnia. In intensive field studies in the central area of the Gulf of Finland, roughly 65-70% of chicks died in their nest in the 1980s and 1990s due to innate diseases. In the 1990s, the fledging rate was only 0.02. The diseases consisted mainly of liver degeneration and various inflammations, and most chicks died of sepsis. The hepatic concentrations of legacy organochlorines (OC) in dead chicks were high, and they correlated with the proportion of dead chicks in a brood. During the 2000s, however, the occurrence of diseased chicks in the Gulf of Finland decreased to 48%, which helped to achieve a fledging rate supposedly sustaining the population (0.52). At the same time, the trends in hepatic levels of certain legacy OCs in chicks decreased, especially the DDE, HCB, β-HCH, and iraws-nonachlor levels. In spite of skewed sampling (only dead chicks were available), our results indicate an enhancing health status among the present population, probably due to a less contaminated diet during the non-breeding period. Article in Journal/Newspaper Larus fuscus fuscus Lesser black-backed gull Federation of Finnish Learned Societies: Scientific Journals Online |
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Open Polar |
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Federation of Finnish Learned Societies: Scientific Journals Online |
op_collection_id |
fttsvojs |
language |
English |
description |
Severe reproductive failure has contributed to a drastic population decline of the nominate Lesser Black-backed Gull (Larus fuscus fuscus) in its breeding grounds in the Gulf of Finland and the Bay of Bothnia. In intensive field studies in the central area of the Gulf of Finland, roughly 65-70% of chicks died in their nest in the 1980s and 1990s due to innate diseases. In the 1990s, the fledging rate was only 0.02. The diseases consisted mainly of liver degeneration and various inflammations, and most chicks died of sepsis. The hepatic concentrations of legacy organochlorines (OC) in dead chicks were high, and they correlated with the proportion of dead chicks in a brood. During the 2000s, however, the occurrence of diseased chicks in the Gulf of Finland decreased to 48%, which helped to achieve a fledging rate supposedly sustaining the population (0.52). At the same time, the trends in hepatic levels of certain legacy OCs in chicks decreased, especially the DDE, HCB, β-HCH, and iraws-nonachlor levels. In spite of skewed sampling (only dead chicks were available), our results indicate an enhancing health status among the present population, probably due to a less contaminated diet during the non-breeding period. |
format |
Article in Journal/Newspaper |
author |
Hario, M. Nuutinen, J. M. J. |
spellingShingle |
Hario, M. Nuutinen, J. M. J. Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
author_facet |
Hario, M. Nuutinen, J. M. J. |
author_sort |
Hario, M. |
title |
Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
title_short |
Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
title_full |
Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
title_fullStr |
Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
title_full_unstemmed |
Varying chick mortality in an organochlorine-“strained” population of the nominate Lesser Black-backed Gull Larus f. fuscus in the Baltic Sea |
title_sort |
varying chick mortality in an organochlorine-“strained” population of the nominate lesser black-backed gull larus f. fuscus in the baltic sea |
publisher |
BirdLife Finland |
publishDate |
2011 |
url |
https://ornisfennica.journal.fi/article/view/133758 |
genre |
Larus fuscus fuscus Lesser black-backed gull |
genre_facet |
Larus fuscus fuscus Lesser black-backed gull |
op_source |
Ornis Fennica; Vol 88 Nro 1 (2011); 1–13 Ornis Fennica; Vol. 88 No. 1 (2011); 1–13 0030-5685 |
op_relation |
https://ornisfennica.journal.fi/article/view/133758/82308 https://ornisfennica.journal.fi/article/view/133758 |
_version_ |
1776201564137979904 |