Coastal habitats and their importance for the diversity of benthic communities: A species- and trait-based approach

Predation risk and competition affect habitat use of adult perch, Perca fluviatilis

“…Indeed, the two fish species occupy the same benthic habitats at several locations, such as the Baltic Sea, Lake Constance and Swedish lakes, with only slight differences in their distribution (Bergman, 1988(Bergman, , 1991Fischer & Eckmann, 1997;Henseler et al, 2019;Mustamäki et al, 2016). In addition to overlap in habitat preference and occupancy, P. fluviatilis and G. cernuus possess similar diets, potentially causing competition.…”

“…This study instead assessed the effects of predator presence for adult P. fluviatilis (~15 cm in size) to examine whether their habitat use is affected the same way by a predator (pike Esox lucius L. 1758), as has been shown for juveniles. Additionally, the impact of competition on habitat use of adult P. fluviatilis was tested using G. cernuus as the potentially competing species, as both species use the same habitats and are benthic feeders preying on macroinvertebrates during all (G. cernuus) or some (P. fluviatilis) life stages (Bergman, 1991;Fischer & Eckmann, 1997;Henseler et al, 2019;Schleuter & Eckmann, 2008). In this study, the term "competition" was used in the context of studying behaviour that could be linked to direct interference regarding habitat use between different individuals, and thus, does not include other aspects of competition, such as resource competition.…”

Mediterranean nekton traits: distribution, relationships and significance for marine ecology monitoring and management

“…Highlighting the importance of traits at the population scale comes easily, as traits are related to the adaptations of the species to its environment aiming to maximize fitness at the individual and population level (Violle et al, 2007). Various works have examined the significance of traits for the population/species possessing them (e.g., Tornroos & Bonsdorff, 2012;Costello et al, 2015;Henseler et al, 2019). Villéger et al (2017) expand the relation of functioning at the population level to ecosystem processes and services.…”

“…Size is important in determining male reproductive success (Wooton, 1999) (continued on next page) Related to individual biomass, food web position, abundance, metabolic rates, and dispersal (Costello et al, 2015) As in the marine ecosystem there is an ''eat what is smaller'' pattern, there has to be some variability in species sizes to support a community (Giacomini, Shuter & Baum, 2016;Kerr & Dickie, 2001) Related to energy flow in the ecosystem (because of association with trophic level/diet) and resulting food webs (Gerlach, Hahn & Schrage, 1985;Jennings, 2005) Relevant for fisheries (with regard to body shape) for selectivity (Jennings, Kaiser & Reynolds, 2001) 6 Body form (flat) Related to position in the water column/habitat, diet/potential prey, activity (Henseler et al, 2019;Wooton, 1999) Because of association with habitat, specific communities may have higher frequencies of some body forms NR Related to the way fishing gear may affect selectivity (together with size) (Jennings, Kaiser & Reynolds, 2001) 7 Optimal depth (0-50 m)…”

“…Defines optimal temperature conditions for population fitness. May affect movement between water masses (behavioural thermoregulation) and thus abundance and distribution (Moyle & Cech Jr, 2004) Due to climate change can shift to dominance of more thermophilic species (Lejeusne et al, 2010) NR More thermophilic species may appear more frequently in the catches ( (Cheung, Watson & Pauly, 2013); Vasilakopoulos et al, 2017) 9 Habitat type (benthic) Populations are closely associated to pelagic or benthic habitat or migrate between them (Henseler et al, 2019;Wooton, 1999) Specific habitats are characterised by specific communities (Ballesteros, 2006;Kalogirou et al, 2010) Effect of seabed type on ecosystem functioning expected to be significant as both are related to biodiversity and its attributes (Loreau et al, 2001) Has implications for target species abundance and bycatch (thus fishing gear use) (Tzanatos et al, 2006) (continued on next page) Related to proximity to the geographic distribution of the area examined (if e.g., through Gibraltar or Suez in the Med) and could be associated to favourable environmental conditions (Coll et al, 2010) Species of alien distribution (invasive) species may dominate the community through colonisation of empty niches/lack of ''natural enemies'' (Givan et al, 2017) NR Climate change or other environmental changes may be forcing changes in distribution paterns (Galil, 2007, Occhipinti-Ambrogi & Savini, 2003 11 Sea bed type (hard) Physical factor determining potential species habitat (Costello et al, 2015) Specific habitats host and are characterized by specific communities (Ballesteros, 2006;Kalogirou et al, 2010) Effect of seabed type on ecosystem functioning expected to be significant as both are related to biodiversity and its attributes (Loreau et al, 2001;Solan, Aspden & Paterson, 2012) Has implications for target species abundance and bycatch (thus gear use) (Tzanatos et al, 2006) 12 Spawning habitat (pelagic)…”