Drivers of kelp distribution in the Gulf of St. Lawrence: insights from a transplant experiment

High‐latitude kelps and future oceans: A review of multiple stressor impacts in a changing world

“…Glaciers discharge freshwater and terrestrial sediments into coastal environments, both of which alter local conditions in a number of ways and impact the structure and function of kelp forests (Spurkland & Iken, 2011a ). Increased sediment load attenuates light penetration, thereby affecting photosynthesis and productivity, and also physically impacts kelp through sediment scour (Aumack et al, 2007 ; Picard, Johnson, Ferrario, et al, 2022 ).…”

“…The literature indicates that scouring effects and burial strongly inhibit spore germination in S. latissima and A. esculenta , gametophyte survival in S. latissima (Traiger & Konar, 2017), and sporophyte germination and growth in M. pyrifera, S. latissima and A. esculenta (Muth et al, 2021;Zacher et al, 2016). Interestingly, however, and Picard, Johnson, Ferrario, et al (2022) show that increased sediment loads actually improve spore attachment in S. latissima, and suggest that this is due to the chemotactic responses of spores to nutrients carried by sediment granules.…”

“…In terms of kelp forests in Alaska, based on the trends observed throughout this review, we would expect S. latissima to expand its distributional range throughout the Alaskan region. This species is relatively warm‐adapted (Andersen et al, 2013 ; Li, Monteiro, et al, 2020 ) and is also resilient to changes in sediment load and light penetration (Picard, Johnson, & Côté, 2022 ; Picard, Johnson, Ferrario, et al, 2022 ; Roleda & Dethleff, 2011 ; Traiger & Konar, 2017 ), and will therefore be able to persist in warming waters and glacially‐influenced areas. Macrocystis pyrifera is also likely to expand northwards and may come to dominate the high‐latitude subtidal in wave‐influenced areas (Hollarsmith et al, 2020 ; Le et al, 2022 ).…”

Macroalgae maintain growth outside their observed distributions: Implications for biodiversity‐ecosystem functioning at landscape scales

“…A meta‐analysis of 14 transplant experiments in plants along elevational gradients found that plants had lower survival in ‘foreign’ habitats compared to their ‘home’ habitat, but reproductive output and biomass production were not affected (Halbritter et al, 2018). In a study using the adults of two kelp species in two different marine habitats (a bay and an island), while one species naturally dominated entirely in the bay, the nondominant kelp species performed better (in terms of both survival and growth), when both species were transplanted into the bay (Picard et al, 2022). The authors speculated that the naturally restricted occurrence of the subdominant species in the bay habitat might be due to constraints during earlier life stages.…”

Nature-based coastal restoration: Development of an early-rearing production protocol of sugar kelp (Saccharina latissima Linnaeus) for bottom planting activities in the Gulf of St-Lawrence (Québec, Canada)

“…Based on different attributes, considered indigenous kelp species for our trials were: Saccharina latissima (Laminariaceae), Saccorhiza dermatodea, Agarum clathratum (Phaeophyceae) and Alaria esculenta (Alariaceae). This study focused on the production of the sugar kelp, Saccharina latissimi based on: 1) the availability of well-developed and simple culture protocols (Tamigneaux et al, 2014;Kerrison et al, 2020;Solvang et al, 2021); 2) their predominance in the areas of Quebec targeted for coastal restoration efforts (Tamigneaux and Johnson, 2016); 3) high growth rate (Reid et al, 2013); 4) well developed holdfast securing anchoring (Kerrison et al, 2019); 5) strong potential as a candidate species for aquaculture diversification in the North Atlantic (Tamigneaux and Johnson, 2016;Forbord et al, 2018;Visch et al, 2020) and 6) provision of substantial ecosystem services (Hasselström et al, 2018;Grebe et al, 2019;Boderskov et al, 2021;Picard et al, 2022).…”