alexa Jellyfish and Ctenophores in the Environmentally Degraded Limfjorden (Denmark) During 2014 - Species Composition, Population Densities and Predation Impact | Abstract
ISSN: 2150-3508

Fisheries and Aquaculture Journal
Open Access

OMICS International organises 3000+ Global Conferenceseries Events every year across USA, Europe & Asia with support from 1000 more scientific Societies and Publishes 700+ Open Access Journals which contains over 50000 eminent personalities, reputed scientists as editorial board members.

Open Access Journals gaining more Readers and Citations

700 Journals and 15,000,000 Readers Each Journal is getting 25,000+ Readers

This Readership is 10 times more when compared to other Subscription Journals (Source: Google Analytics)

Research Article

Jellyfish and Ctenophores in the Environmentally Degraded Limfjorden (Denmark) During 2014 - Species Composition, Population Densities and Predation Impact

Hans Ulrik Riisgård1*, Josephine Goldstein1,2, Kim Lundgreen1,2 and Florian Lüskow1

1Marine Biological Research Centre, University of Southern Denmark, Hindsholmvej 11, DK-5300 Kerteminde, Denmark

2Max-Planck Odense Center on the Biodemography of Aging and Department of Biology, Campusvej 55, DK-5230 Odense M, Denmark

Corresponding Author:
Hans Ulrik Riisgård
Marine Biological Research Centre
University of Southern Denmark
Hindsholmvej 11, DK-5300 Kerteminde, Denmark
Tel: 65321433
Fax: 65321433
E-mail: [email protected]

Received Date: April 22, 2015; Accepted Date: July 24, 2015; Published Date: July 28, 2015

Citation: Riisgård HU, Goldstein J, Lundgreen K, Lüskow F (2015) Jellyfish and Ctenophores in the Environmentally Degraded Limfjorden (Denmark) During 2014 - Species Composition, Population Densities and Predation Impact. Fish Aquac J 6:137. doi:10.4172/2150-3508.1000137

Copyright: © 2015 Riisgård HU, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Species composition, population densities and size of jellyfish and ctenophores were recorded during 5 cruises in the heavily eutrophicated Limfjorden in 2014. No or very few ctenophores (Pleurobrachia pileus) and jellyfish (Aurelia aurita, Cyanea lamarckii) were recorded in April and June 2014, whereas in August and September numerous small individuals of the invasive ctenophore Mnemiopsis leidyi were found on all 4 locations studied, which were strongly reduced in population density during November. M. leidyi exerted a notable predation impact, most pronounced in Løgstør Bredning and Skive Fjord in August when the estimated half-lives of zooplankton were 4.8 and 7.3 d, respectively, and in late September, when the half-life in Skive Fjord was only 2.2 d. Severe oxygen depletion in Løgstør Bredning and Skive Fjord between June and September resulted in a release of nutrients. This was followed by a bloom of the dinoflagellate Noctiluca scintillans and a subsequent peak in the abundance of copepods which decreased rapidly after the introduction of M. leidyi into Limfjorden from the North Sea (between early April and mid- July) to become virtually absent during the rest of the season. This subsequently resulted in starvation and decay of the M. leidyi population. The small predatory ctenophore Beroe gracilis was recorded on most locations during August and September 2014 but although B. gracilis eats small M. leidyi, their low number suggested a negligible predation impact on the M. leidyi population. Our present understanding of the many biological and environmental factors that control the species composition, abundance and predation impact of jellyfish and ctenophore populations in Limfjorden are discussed. It is concluded that there are many unsolved questions, e.g. how gelatinous predation of zooplankton may reinforce anoxia and further habitat degradation in eutrophicated waters.

Keywords

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2018-19
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri & Aquaculture Journals

Dr. Krish

[email protected]

1-702-714-7001Extn: 9040

Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001Extn: 9040

Clinical Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

Food & Nutrition Journals

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

General Science

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics & Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Materials Science Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Nursing & Health Care Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Medical Journals

Nimmi Anna

[email protected]

1-702-714-7001Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

Ann Jose

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001Extn: 9042

 
© 2008- 2018 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version