title: Future climate change is predicted to shift long-term persistence zones in the cold-temperate kelp Laminaria hyperborea.
abstract: Global climate change is shifting species distributions worldwide. At rear edges (warmer, low latitude range margins), the consequences of small variations in environmental conditions can be magnified, producing large negative effects on species ranges. A major outcome of shifts in distributions that only recently received attention is the potential to reduce the levels of intra-specific diversity and consequently the global evolutionary and adaptive capacity of species to face novel disturbances. This is particularly important for low dispersal marine species, such as kelps, that generally retain high and unique genetic diversity at rear ranges resulting from long-term persistence, while ranges shifts during climatic glacial/interglacial cycles. Using ecological niche modelling, we (1) infer the major environmental forces shaping the distribution of a cold-temperate kelp, Laminaria hyperborea (Gunnerus) Foslie, and we (2) predict the effect of past climate changes in shaping regions of long-term persistence (i.e., climatic refugia), where this species might hypothetically harbour higher genetic diversity given the absence of bottlenecks and local extinctions over the long term. We further (3) assessed the consequences of future climate for the fate of L. hyperborea using different scenarios of greenhouse gas emissions (RCP 2.6 and RCP 8.5). Results show NW Iberia, SW Ireland and W English Channel, Faroe Islands and S Iceland, as regions where L. hyperborea may have persisted during past climate extremes until present day. All predictions for the future showed expansions to northern territories coupled with the significant loss of suitable habitats at low latitude range margins, where long-term persistence was inferred (e.g., NW Iberia). This pattern was particularly evident in the most agressive scenario of climate change (RCP 8.5), likely driving major biodiversity loss, changes in ecosystem functioning and the impoverishment of the global gene pool of L. hyperborea. Because no genetic baseline is currently available for this species, our results may represent a first step in informing conservation and mitigation strategies.
authors.affiliation: CCMAR, University of Algarve, Campus de Gambelas, Faro 8005-139, Portugal. Electronic address: jorgemfa@gmail.com.
authors.forename: Jorge
authors.initials: J
authors.lastname: Assis
authors.affiliation: CCMAR, University of Algarve, Campus de Gambelas, Faro 8005-139, Portugal.
authors.forename: Ana Vaz
authors.initials: AV
authors.lastname: Lucas
authors.affiliation: Grupo BioCost, Departamento de Bioloxía Animal, Vexetal e Ecoloxía, Facultade de Ciencias, Universidade da Coruña, Campus de A Zapateira, 15071 A Coruña, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Bárbara
authors.affiliation: CCMAR, University of Algarve, Campus de Gambelas, Faro 8005-139, Portugal.
authors.forename: Ester Álvares
authors.initials: EÁ
authors.lastname: Serrão
mesh_terms: D057231:Climate Change; D003080:Cold Temperature; D003710:Demography; D017753:Ecosystem; D005060:Europe; D007795:Laminaria / Q000502:physiology*; D009792:Oceans and Seas; D058974:Phylogeography
keywords: Climate change; Ecologial niche modelling; Kelp forests; Laminaria hyperborea; Local persistence; Phylogeography; Range shifts