Universität zu Köln

Bleeker, Katinka, de Jong, Karen ORCID: 0000-0001-9239-7268, van Kessel, Nils, Hinde, Camilla A. and Nagelkerke, Leopold A. J. (2017). Evidence for ontogenetically and morphologically distinct alternative reproductive tactics in the invasive Round Goby Neogobius melanostomus. PLoS One, 12 (4). SAN FRANCISCO: PUBLIC LIBRARY SCIENCE. ISSN 1932-6203

Full text not available from this repository.

Abstract

Alternative reproductive tactics are characterized by the occurrence of discrete alternative morphs that differ in behavioural, morphological and physiological traits within the same sex. Although much effort has been made to describe the behaviour, morphology and physiology of such alternative morphs, less effort has been invested investigating how much overlap there is in the characteristics of such morphs in natural populations. We studied random population samples of the invasive Round Goby Neogobius melanostomus from five different localities in the river Rhine system in the Netherlands. We found two morphologically and physiologically distinct male morphs which likely represent alternative reproductive tactics. Almost all mature males under 9.35 cm total length had a gonadosomatic index > 3%, suggestive of a sneaker tactic, while nearly all males above 9.35 cm has a gonadosomatic index of < 3%, suggestive of a parental tactic. Cheek size and eye diameter alone were sufficient to distinguish the two morphs. Gonads had a different relationship with size in the two morphs, indicating separate growth trajectories. The gonad mass of sneaker morphs would be ca. 7.5 times as high as the gonad mass of parental morphs of the same total length after extrapolation. Few (9%) intermediates were found, suggesting that the expression of alternative reproductive tactics is determined before the first breeding season. This contrasts with studies on other goby species, which show evidence of plastic tactics that can be affected by social circumstances. We conclude that it is possible to distinguish two alternative male morphs in the Dutch Round Goby population using morphological measurements alone. Although behavioural observations are needed to provide conclusive evidence, the difference in GSI between these morphs indicates that these morphs reflect alternative reproductive tactics.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Bleeker, Katinka UNSPECIFIED UNSPECIFIED UNSPECIFIED de Jong, Karen UNSPECIFIED orcid.org/0000-0001-9239-7268 UNSPECIFIED van Kessel, Nils UNSPECIFIED UNSPECIFIED UNSPECIFIED Hinde, Camilla A. UNSPECIFIED UNSPECIFIED UNSPECIFIED Nagelkerke, Leopold A. J. UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-234173
DOI:	10.1371/journal.pone.0174828
Journal or Publication Title:	PLoS One
Volume:	12
Number:	4
Date:	2017
Publisher:	PUBLIC LIBRARY SCIENCE
Place of Publication:	SAN FRANCISCO
ISSN:	1932-6203
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language ZOSTERISESSOR-OPHIOCEPHALUS TELEOSTEI; MALE MATING TACTICS; SPERM COMPETITION; BOURGEOIS; SUCCESS; FISH; FERTILIZATION; INVESTMENT; STRATEGIES; BEHAVIOR Multiple languages Multidisciplinary Sciences Multiple languages
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/23417