A1 Journal article (refereed)
Population and reproductive dynamics of the polychaete Pygospio elegans in a boreal estuary complex (2016)


Thonig, A., Knott, E., Kesäniemi, J., Hansen, B. W., & Banta, G. T. (2016). Population and reproductive dynamics of the polychaete Pygospio elegans in a boreal estuary complex. Invertebrate Biology, 135(4), 370-384. https://doi.org/10.1111/ivb.12149


JYU authors or editors


Publication details

All authors or editorsThonig, Anne; Knott, Emily; Kesäniemi, Jenni; Hansen, Benni Winding; Banta, Gary Thomas

Journal or seriesInvertebrate Biology

ISSN1077-8306

eISSN1744-7410

Publication year2016

Volume135

Issue number4

Pages range370-384

PublisherWiley-Blackwell Publishing, Inc.; American Microscopical Society

Publication countryUnited Kingdom

Publication languageEnglish

DOIhttps://doi.org/10.1111/ivb.12149

Publication open accessNot open

Publication channel open access


Abstract

Pygospio elegans is an opportunistic, wide‐spread spionid polychaete that reproduces asexually via fragmentation and can produce benthic and pelagic larvae, hence combining different developmental modes in one species. We documented the density, size distribution, and reproductive activity of P. elegans at four sites in the Danish Isefjord‐Roskilde Fjord estuary complex, where all modes of reproduction were reported. We compared population dynamics of this species to environmental parameters such as salinity, temperature, and sediment characteristics (grain size, sorting, porosity, water content, organic content, C/N). We observed that new cohorts—resulting either from sexual or asexual reproduction—appeared in spring and fall, and old ones disappeared in late summer and winter. Sexual reproduction occurred from September until May, and although their timing was variable, there were two reproductive peaks at three sites. At those sites, we also observed a switch in larval developmental mode. Asexual reproduction peaked in April. While the seasonal dynamics can be related to temperature to a large extent, the differences in population dynamics among sites also correlated with sediment structure and salinity. Populations from sites with coarse and heterogeneous sediment had high levels of sexual reproduction. At the site with lower salinity, intermediate and benthic larvae were present during winter in contrast to pelagic larvae found at the other sites. However, we could not identify one clear environmental factor determining the mode of development. At present, it remains unclear to what degree genetic background contributes to mode of development. Hence, whether the differences in developmental mode are the result of genetically different cohorts will be further investigated.


Keywordslife history

Free keywordspoecilogony; development; spatiotemporal variation; environmental impact


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Ministry reportingYes

VIRTA submission year2016

JUFO rating1


Last updated on 2024-11-10 at 18:30