Beak length analysis of loligo forbesi, Todarodes sagittatus and Todaropsis eblanae from the northern North Sea

A detailed analysis of lower rostral beak length (LRL) to body size and wet body mass measurements was carried out for the squids Loligo forbesi, Todarodes sagittatus and Todaropsis eblanae. Specimens were sampled in the northern North Sea during two research cruises of FRV WALTHER HERWIG III in Jan...

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Bibliographic Details
Main Authors: Zumholz, Karsten, Piatkowski, Uwe
Format: Article in Journal/Newspaper
Language:unknown
Published: University of Miami - Rosenstiel School of Marine and Atmospheric Science 2002
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Online Access:https://oceanrep.geomar.de/id/eprint/39408/
Description
Summary:A detailed analysis of lower rostral beak length (LRL) to body size and wet body mass measurements was carried out for the squids Loligo forbesi, Todarodes sagittatus and Todaropsis eblanae. Specimens were sampled in the northern North Sea during two research cruises of FRV WALTHER HERWIG III in January/February of 1998 and 1999. Altogether 241 specimens of Loligo forbesi (ML = 45–376 mm), 108 specimens of Todarodes sagittatus (ML = 173–325 mm) and 97 specimens of Todaropsis eblanae (ML = 30–127 mm) were investigated to correlate lower rostral beak length with both mantle length and wet body mass. Linear relationships between LRL and mantle length and powerfunctional relationships between LRL and wet body mass were calculated for all three species. By calculating these correlations separately for males and females, no obvious sex-specific relationships were found. The presented data will upgrade the information on beak/mantle length/body mass relationships of major cephalopod species of the North Sea. They provide essential information for future use in estimates of cephalopod prey biomass in North East Atlantic top predators such as whales, seals, seabirds and fishes.