Temperate fish community variation over seasons in relation to large-scale geographic seascape variables

Abstract

In shallow-water marine environments, ecosystem functioning is a complex interworking of fine-scale characteristics and region-wide factors, and the importance of these variables can vary on multiple temporal and spatial scales. This underwater video study targeted seasonal changes in the fish community of seagrass habitats along the Swedish west coast and the influence of offshore seascape variables (latitudinal position, wave exposure, open ocean, and deep water). Results showed that fish assemblage structure exhibited seasonal changes between summer and autumn and strong spatiotemporal variations in the importance of offshore factors affecting shallow-water fish communities. In summer, abundance from the Gobiidae family responded to wave exposure, whereas the Gadidae family and juvenile migrant habitat preference guild responded to latitudinal position and proximity to deep water. In autumn, deep water was related to abundance of Gadidae and juvenile migrants, whereas latitudinal position influenced Gasterosteidae. These findings underscore the importance of understanding the influence of offshore factors on facets of coastal fish assemblages to address large-scale geographic connectivity along nearshore–offshore gradients.

Habitat Connectivity of Fish in Temperate Shallow-Water Seascapes

“…Subsequently, abundances were calculated (m −2 ) based on fish activity. This was defined as the number of instances fish entered the field of view divided by the recording area, which therefore corrects for the variation in visibility among sites (Hammar et al, 2015;Perry et al, 2017). Field of view is defined by the maximum distance at which a recorded fish is identified for each specific film.…”

“…Additionally, species were grouped into guilds based on habitat preference in order to elucidate similarities and differences in fish assemblage structure between various coastal shallow-water habitats, to understand species connectivity between habitats. Guilds were selected based on information from FishBase (Froese and Pauly, 2015) and other sources (Elliott and DeWailly, 1995;Pihl and Wennhage, 2002;Pihl et al, 2006;Perry et al, 2017;Staveley et al, 2017). The guild groupings were as follows: stationary species (SS), shallowwater generalists (SWG), occasional shallow-water visitors (OSV) and juvenile migrants (JM).…”

“…A tremendous effort has been made toward describing and comparing distribution patterns of fish in different shallow-water habitats (e.g., Dean et al, 2000;Mathieson et al, 2000;Able, 2005;Dorenbosch et al, 2007;Reiss et al, 2010), such as the significant role of seagrass meadows as nursery grounds (reviewed by Heck et al, 2003). However, in temperate waters the strength of habitat linkages and the relative importance of multiple habitats from a seascape perspective (considering ecological functions in relation to spatial patterns) has, as yet, been given sparse attention (see Perry et al, 2017;Staveley et al, 2017).…”

Exploring seagrass fish assemblages in relation to the habitat patch mosaic in the brackish Baltic Sea

“…Note: low-and mid-level carnivore biomass models for the autumn were not generated in Baltic Sea coastal areas; a recent study reported a 45-times increase from 1980 to 2011 in the central Baltic Sea (Bergström et al 2015). In Z. marina meadows on the Swedish west coast, this species has also increased substantially in the past few decades and is now one of the most abundant fish found in these habitats (Baden et al 2012;Staveley et al 2017;Perry et al 2018b).…”

Utilization of species checklist data in revealing the spatial distribution of fish diversity

“…Various fish species are widely distributed and are integrally linked to their environment (Perry et al, 2018). The taxonomic variation of fish assemblages is important for the maintenance of ecosystem stability (Sun et al, 2010).…”