Long-term dynamics, population structure and connectivity of the helmet jellyfish Periphylla periphylla in a Norwegian fjord and adjacent waters.

ABSTRACT: Mass occurrences of Periphylla periphylla in Norwegian fjords cause major concerns related to potential regime shifts that could affect ecosystem stability. 15 years of trawl data (2006-2015), complemented with comprehensive sampling in different areas and seasons (2018-2021) allowed new insights on the dynamics, structure and connectivity of P. periphylla populations within and beyond Trondheimsfjorden. Despite assumed population bursts, no clear trend on P. periphylla population size in Trondheimsfjorden were identified. Sampling frequency and population size suggest a local reproduction of P. periphylla, especially in the inner part of the fjord where young-of-the-year (YOY) individuals occur. Size variations occurred in relation to sampling month, thus point

SUBMITTER: Aberle N 

PROVIDER: S-EPMC10810686 | biostudies-literature | 2024 Jan-Feb

REPOSITORIES: biostudies-literature