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Forest fires are drivers of spatial patterns and temporal dynamics of vegetation and biodiversity. On the Canary Islands, large areas of pine forest exist, dominated by the endemic Canary Island pine, Pinus canariensis C. Sm. These mostly natural forests experience wildfires frequently. P. canariensis is well-adapted to such impacts and has the ability to re-sprout from both stems and branches. In recent decades, however, anthropogenically caused fires have increased, and climate change further enhances the likelihood of large forest fires. Through its dense, long needles, P. canariensis promotes cloud precipitation, which is an important ecosystem service for the freshwater supply of islands such as La Palma. Thus, it is important to understand the regeneration and vegetation dynamics of these ecosystems after fire. Here, we investigated species diversity patterns in the understory vegetation of P. canariensis forests after the large 2016 fire on the southern slopes of La Palma. We analyzed the effect of fire intensity, derived from Sentinel-2 NDVI differences, and of environmental variables, on species richness (alpha diversity) and compositional dissimilarity (beta diversity). We used redundancy analysis (dbRDA), Bray-Curtis dissimilarity, and variance partitioning for this analysis.

During his explorations in temperate and tropical mountains, Humboldt made crucial observations about the importance of elevational climate gradients as drivers for biodiversity. We show here that pollen deposition may be a suitable, and statistically robust proxy for climate-driven elevational eco-gradients, thus assisting in the interpretation of modern ecosystem dynamics as well as in past climate reconstructions from fossil records. Our specific challenges are: (1) to derive consistent pollen-climate relationships in complex mountain regions bearing differences in local climates and intensity of human impact; (2) to find potential indicator taxa useful for paleoclimate reconstructions; (3) to estimate the effect of local parameters on the relationships linking pollen percentages variations, elevation and climate and put forward new hints for calibration of fossil sites; (4) to obtain quantitative climate reconstructions and compare the results with instrumental modelled data and finally (5) to integrate the newly-obtained pollen spectra into larger modern pollen samples datasets. We analyzed pollen deposition in the European Alps and the Canaries, captured by surface samples (subsampling mosses, forest litter, surface soil in open ground land) and artificial traps both at the ground level and over it. To examine the variance explained by climate parameters, elevational training sets were equipped with site-specific climatologies, together with an array of environmental variables (i.e. proxies for fire, nutrients, pastoralism, terrain parameters, plant cover). The potential for a quantitative reconstruction of sensible climate parameters was tested by canonical correspondence analysis (CCA), enhanced hierarchical logistic regression (extended eHOF models), and weighted averaging (WA).

Aim: To quantify the influence of past archipelago configuration on present-day insular biodiversity patterns, and to compare the role of long-lasting archipelago configurations over the Pleistocene to configurations of short duration such as at the Last Glacial Maximum (LGM) and the present-day. Location: 53 volcanic oceanic islands from 12 archipelagos worldwide—Azores, Canary Islands, Cook Islands, Galápagos, Gulf of Guinea, Hawaii, Madeira, Mascarenes, Pitcairn, Revillagigedo, Samoan Islands and Tristan da Cunha. Time period: The last 800 kyr, representing the nine most recent glacial–interglacial cycles. Major taxa studied: Land snails and angiosperms. Methods: Species richness data for land snails and angiosperms were compiled from existing literature and species checklists. We reconstructed archipelago configurations at the following sea levels: the present-day high interglacial sea level, the intermediate sea levels that are representative of the Pleistocene and the low sea levels of the LGM. We fitted two alternative linear mixed models for each archipelago configuration using the number of single-island endemic, multiple-island endemic and (non-endemic) native species as a response. Model performance was assessed based on the goodness-of-fit of the full model, the variance explained by archipelago configuration and model parsimony. Results: Single-island endemic richness in both taxonomic groups was best explained by intermediate palaeo-configuration (positively by area change, and negatively by palaeo-connectedness), whereas non-endemic native species richness was poorly explained by palaeo-configuration. Single-island endemic richness was better explained by intermediate archipelago configurations than by the archipelago configurations of the LGM or present-day. Main conclusions: Archipelago configurations at intermediate sea levels—which are representative of the Pleistocene—have left a stronger imprint on single-island endemic richness patterns on volcanic oceanic islands than extreme archipelago configurations that persisted for only a few thousand years (such as the LGM). In understanding ecological and evolutionary dynamics of insular biota it is essential to consider longer-lasting environmental conditions, rather than extreme situations alone. © 2018 John Wiley & Sons Ltd

The term meta-archipelago has been in use in cultural studies for some time, to refer to certain complex island areas in which the boundaries between conventionally recognised archipelagos are indistinct, although the concept also carries additional connotations. Use of the term in biogeography appears more recent and without effort to prescribe its meaning. We outline, from a biogeographical perspective, distinctions between meta-archipelagos and archipelagos and those islands not occurring within either collective grouping, highlighting that network analysis tools provide metrics for formal analytical purposes. © The authors.

The general dynamic model of oceanic island biogeography (GDM) has added a new dimension to theoretical island biogeography in recognizing that geological processes are key drivers of the evolutionary processes of diversification and extinction within remote islands. It provides a dynamic and essentially non-equilibrium framework generating novel predictions for emergent diversity properties of oceanic islands and archipelagos. Its publication in 2008 coincided with, and spurred on, renewed attention to the dynamics of remote islands. We review progress, both in testing the GDM’s predictions and in developing and enhancing ecological–evolutionary understanding of oceanic island systems through the lens of the GDM. In particular, we focus on four main themes: (i) macroecological tests using a space-for-time rationale; (ii) extensions of theory to islands following different patterns of ontogeny; (iii) the implications of GDM dynamics for lineage diversification and trait evolution; and (iv) the potential for downscaling GDM dynamics to local-scale ecological patterns and processes within islands. We also consider the implications of the GDM for understanding patterns of non-native species diversity. We demonstrate the vitality of the field of island biogeography by identifying a range of potentially productive lines for future research. © 2016 Cambridge Philosophical Society.

Islands provide classic model biological systems. We review how growing appreciation of geoenvironmental dynamics of marine islands has led to advances in island biogeographic theory accommodating both evolutionary and ecological phenomena. Recognition of distinct island geodynamics permits general models to be developed and modified to account for patterns of diversity, diversification, lineage development, and trait evolution within and across island archipelagos. Emergent patterns of diversity include predictable variation in island species-area relationships, progression rule colonization from older to younger land masses, and syndromes including loss of dispersability and secondary woodiness in herbaceous plant lineages. Further developments in Earth system science, molecular biology, and trait data for islands hold continued promise for unlocking many of the unresolved questions in evolutionary biology and biogeography.

Aims: The 50th anniversary of the publication of the seminal book, The Theory of Island Biogeography, by Robert H. MacArthur and Edward O. Wilson, is a timely moment to review and identify key research foci that could advance island biology. Here, we take a collaborative horizon-scanning approach to identify 50 fundamental questions for the continued development of the field. Location: Worldwide. Methods: We adapted a well-established methodology of horizon scanning to identify priority research questions in island biology, and initiated it during the Island Biology 2016 conference held in the Azores. A multidisciplinary working group prepared an initial pool of 187 questions. A series of online surveys was then used to refine a list of the 50 top priority questions. The final shortlist was restricted to questions with a broad conceptual scope, and which should be answerable through achievable research approaches. Results: Questions were structured around four broad and partially overlapping island topics, including: (Macro)Ecology and Biogeography, (Macro)Evolution, Community Ecology, and Conservation and Management. These topics were then subdivided according to the following subject areas: global diversity patterns (five questions in total); island ontogeny and past climate change (4); island rules and syndromes (3); island biogeography theory (4); immigration–speciation–extinction dynamics (5); speciation and diversification (4); dispersal and colonization (3); community assembly (6); biotic interactions (2); global change (5); conservation and management policies (5); and invasive alien species (4). Main conclusions: Collectively, this cross-disciplinary set of topics covering the 50 fundamental questions has the potential to stimulate and guide future research in island biology. By covering fields ranging from biogeography, community ecology and evolution to global change, this horizon scan may help to foster the formation of interdisciplinary research networks, enhancing joint efforts to better understand the past, present and future of island biotas. © 2017 John Wiley & Sons Ltd

The monitoring plan of a Marine Protected Area (MPA) is a fundamental element within its management plan, being designed for meeting the requirements of the site, as well as controlling and informing about the processes affecting the system analysed. Despite its importance, several deficiencies have been found in the monitoring and management plans of the Special Areas of Conservation (SACs) of the Macaronesian Region within Natura 2000 network. One of these shortfalls deals with the indicators selected. Taking advantage of the need of producing a management plan for upgrading the Banco de La Concepción to a SAC, a methodology able to deal with this issue and to generate the necessary guidelines and recommendations on which the management plan can be based, has been set up. Banco de La Concepción is an offshore seamount located in the Macaronesian biogeographical region, characterized by being a spot of high productivity and biodiversity within a more oligotrophic environment. Among the communities and species existing there we can highlight the presence of reef communities considered a priority habitat and included in the Annex I of the European Habitats Directive as sensitive habitat, as well as the presence of the loggerhead sea turtle (Caretta caretta) and the bottlenose dolphin (Tursiops truncatus), both sensitive species included in the Annex II of the same directive. The methods used have been various including: i) the development of a driver-pressure-state-impacts-response (DPSIR) conceptual model, with the aim of determining the elements affecting the MPA for selecting a suitable list of indicators, ii) the Delphi method for incorporating the experts’ opinion, and iii) the implementation of a Multicriteria-Decision-Analysis (MCDA) approach, specifically the Analytical-Hierarchy-Process (AHP) for determining the suitability of the indicators for the evaluated system, thus generating a novel methodological combination used for the first time in a Spain for MPA evaluation. The results obtained highlight the suitability of 18 indicators from 144 initially detected, divided within four groups considered (driving forces, pressures, state/impact and responses). Among them “Fishing effort”, “Catch per unit effort”, “Extent of Habitats/Communities” and “Existence and adoption of a monitoring plan” stand out as the more appropriate for each group regarding the Banco de La Concepción monitoring. Finally, the advices given by the project INDEMARES have been followed and an alternative methodology able to perform in a transparent way the selection of indicators for the Spanish marine SACs management plans, which they currently lack, has been developed.

Since the contributions of Charles Darwin and Alfred Russel Wallace, oceanic archipelagos have played a central role in the development of biogeography. However, despite the critical influence of oceanic islands on ecological and evolutionary theory, our focus has remained limited to either the island-level of specific archipelagos or single archipelagos. Recently, it was proposed that oceanic archipelagos qualify as biotic provinces, with diversity primarily reflecting a balance between speciation and extinction, with colonization having a minor role. Here we focus on major attributes of the archipelagic geological dynamics that can affect diversity at both the island and the archipelagic level. We also reaffirm that oceanic archipelagos are appropriate spatiotemporal units to frame analyses in order to understand large scale patterns of biodiversity. © 2016 the authors.

The monitoring plan of a Marine Protected Area (MPA) is a fundamental element within its management plan, being designed for meeting the requirements of the site, as well as controlling and informing about the processes affecting the system analysed. Despite its importance, several deficiencies have been found in the monitoring and management plans of the Special Areas of Conservation (SACs) of the Macaronesian Region within Natura 2000 network. One of these shortfalls deals with the indicators selected. Taking advantage of the need of producing a management plan for upgrading the Banco de La Concepción to a SAC, a methodology able to deal with this issue and to generate the necessary guidelines and recommendations on which the management plan can be based, has been set up. Banco de La Concepción is an offshore seamount located in the Macaronesian biogeographical region, characterized by being a spot of high productivity and biodiversity within a more oligotrophic environment. Among the communities and species existing there we can highlight the presence of reef communities considered a priority habitat and included in the Annex I of the European Habitats Directive as sensitive habitat, as well as the presence of the loggerhead sea turtle (Caretta caretta) and the bottlenose dolphin (Tursiops truncatus), both sensitive species included in the Annex II of the same directive. The methods used have been various including: i) the development of a driver-pressure-state-impacts-response (DPSIR) conceptual model, with the aim of determining the elements affecting the MPA for selecting a suitable list of indicators, ii) the Delphi method for incorporating the experts’ opinion, and iii) the implementation of a Multicriteria-Decision-Analysis (MCDA) approach, specifically the Analytical-Hierarchy-Process (AHP) for determining the suitability of the indicators for the evaluated system, thus generating a novel methodological combination used for the first time in a Spain for MPA evaluation. The results obtained highlight the suitability of 18 indicators from 144 initially detected, divided within four groups considered (driving forces, pressures, state/impact and responses). Among them “Fishing effort”, “Catch per unit effort”, “Extent of Habitats/Communities” and “Existence and adoption of a monitoring plan” stand out as the more appropriate for each group regarding the Banco de La Concepción monitoring. Finally, the advices given by the project INDEMARES have been followed and an alternative methodology able to perform in a transparent way the selection of indicators for the Spanish marine SACs management plans, which they currently lack, has been developed.

The study of islands as model systems has played an important role in the development of evolutionary and ecological theory. The 50th anniversary of MacArthur and Wilson's (December 1963) article, 'An equilibrium theory of insular zoogeography', was a recent milestone for this theme. Since 1963, island systems have provided new insights into the formation of ecological communities. Here, building on such developments, we highlight prospects for research on islands to improve our understanding of the ecology and evolution of communities in general. Throughout, we emphasise how attributes of islands combine to provide unusual research opportunities, the implications of which stretch far beyond islands. Molecular tools and increasing data acquisition now permit re-assessment of some fundamental issues that interested MacArthur and Wilson. These include the formation of ecological networks, species abundance distributions, and the contribution of evolution to community assembly. We also extend our prospects to other fields of ecology and evolution - understanding ecosystem functioning, speciation and diversification - frequently employing assets of oceanic islands in inferring the geographic area within which evolution has occurred, and potential barriers to gene flow. Although island-based theory is continually being enriched, incorporating non-equilibrium dynamics is identified as a major challenge for the future. © 2014 John Wiley & Sons Ltd/CNRS.

The MacArthur and Wilson island biogeography theory relates species diversity on islands as the result of equilibrium between extinctions and colonization events which rates depend on island size and isolation. Although island size and isolation can be considered static on ecological timescales (

Vegetation dynamics since the last glacial maximum in small oceanic islands and in continental settings are compared. We selected the islands of Minorca (Western Mediterranean), Tenerife (Eastern Atlantic), the Azores (Central Atlantic) and Mauritius (Indian Ocean) and compared pollen-based dynamics with selected continental areas of southern Italy, the Atlas mountains, northwest Africa, and the East African mountains. We identified potential areas where plant diversity is conserved during unfavourable periods serving as refugial areas. Most pollen records from small oceanic islands with a low topography show, as far as the pollen records reach, stable forest compositions suggesting floral diversity is lodged within a mosaic-like structure. In mountainous islands data point to an altitudinal distribution of plant diversity and to altitudinal migration of plants as a response to climate change. In Mauritius we registered at 11.4 cal. ka a climate-forced change in forest composition which triggered a cascade of species turnover events considered as system-driven. In the small islands discussed we identified areas with a high potential to provide on a long-term shelter to insular floral diversity, thus serving as a refugium: 1) gallery forest located along the drainage system (topography constrained), 2) cloud forest located at the elevation where atmospheric moisture condensates and cloud formation takes place (sea surface temperature and atmospheric lapse rate constrained), 3) and deeply incised valleys, connecting diversity between all available elevations, where relatively humid conditions prevail such as the barrancos in Tenerife and the deeply incised valleys in Mauritius (geomorphology and sea-level constrained).

Using the data from six oceanic archipelagos, we investigated the species richness patterns on islands for all natives, archipelagic endemics and single-island endemics of pteridophytes and spermatophytes. We tested the hypothesis that the descriptive ability of biogeographical factors for species is reduced as we move from native species, to archipelagic endemics and to single island endemics, because of the increasing importance of island ‘idiosyncrasies’ (i.e. unique features of each island shaping its biota, such as catastrophic volcanic eruptions, random colonization events, mega-landslides) in controlling the species richness of endemic species. This hypothesis was addressed using two approaches: (1) the island species–area relationships (ISARs), and (2) a multiple regression approach with variable selection based on permutation, to test the combined effects of island area with other biogeographical factors. Area was an effective predictor of species richness for all native species (R 2 = 0.568 and R 2 = 0.624 for pteridophytes and spermatophytes respectively), but its predictive capacity decreased for archipelagic endemics (R 2 = 0.261 and R 2 = 0.531) and single-island endemics (R 2 = 0.084 and R 2 = 0.438). The reduction of R 2 from all native species, to archipelagic endemics and to single-island endemics was attributed to the increasing effects of the ‘idiosyncrasies’ of each island. The predictive capacity of multiple regression models increased with respect to ISARs, ranging from 27.3% (for single-island endemic pteridophytes) to 83.3% (all native pteridophytes), and included three to five predictors. Island area remained the most important variable for spermatophytes but was less important for pteridophytes. For pteridophytes, elevation was the most important predictor for native species, while isolation-related variables were the most important predictors for archipelagic endemics and single-island endemics. Our results support the hypothesis that as we move from native, to archipelagic endemic and to single-island endemic species the predictive ability of models is reduced, indicating an increased effect of the ‘idiosyncratic’ character of islands.

This paper introduces the integration of additive partitioning with species--area relationships to island biogeography in order to address the question "How are the pteridophyte and spermatophyte native and endemic flora of different oceanic archipelagos partitioned across islands?". Species richness data of all endemic species and all native species of pteridophytes and spermatophytes were obtained for the Azores, Canaries and Cape Verde in the Atlantic Ocean and Galbpagos, Hawaii and Marquesas in the Pacific Ocean. Additive partitioning of species diversity was used to quantify how much of the total diversity of an oceanic archipelago flora ([gamma]-diversity) is due to (i) the mean species richness of the flora of each island ([alpha]-diversity), (ii) the variability in species richness of the floras across islands ([beta]Nestedness) and (iii) the complementarity in species composition of the floras of different islands ([beta]Replacement). The analysis was separately performed for the native and endemic pteridophyte and spermatophyte floras. The diversity partitioning of the six archipelagos showed large differences in how the flora of each archipelago is partitioned among the [alpha], [beta]Nestedness and [beta]Replacement components, for pteridophytes and spermatophytes and for all endemic species and all native species. The [alpha]-diversity was more important for all native species than for endemic species and more important for pteridophytes than for spermatophytes, with the Azores showing outstanding high values of [alpha]-diversity. The [beta]Nestedness was higher for pteridophytes than for spermatophytes and higher for endemic species than for all native species in both pteridophytes and spermatophytes. The values of [beta]Replacement suggested that: (i) the spermatophyte native flora is more differentiated across islands than the pteridophyte native flora and (ii) the pteridophyte endemic flora and, especially, the spermatophyte endemic flora are more differentiated across islands than the corresponding native flora. An outstanding value of [beta]Replacement for endemic and all native spermatophytes was found in Hawaii, confirming the biogeographical island differentiation in this archipelago