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Caribbean islands are important hotspots for endemic species, concentrating high biodiversity on exceptionally small areas. Cozumel Island is not an exception, yet little published information exis...

The island laboratory concept has long been an important construct in island archaeology, with an emphasis on human biogeography and issues of isolation, connectivity, interaction, evolution, and e...

The assessment of ecological environment during the large-scale development of islands is a major topic in the study of current coastal islands. Choosing the appropriate assessment method to evaluate the suitability of carrying capacity of islands and making relevant suggestions are significant to the sustainable development of islands. Ecological footprint method is used to analyze the ecological carrying capacity of Pingtan Island (PI) from 2005 to 2016 for promoting the coordinated rational development and construction and ecological environment of the island. Although PI is in rapid urban development and construction, the island maintains secure and stable ecological conditions. PI is used as a research case to analyze the sustainable development of the ecological environment through the carrying capacity of the island ecosystem.

Research in Macaronesia has led to substantial advances in ecology, evolution and conservation biology. We review the scientific developments achieved in this region, and outline promising research avenues enhancing conservation. Some of these discoveries indicate that the Macaronesian flora and fauna are composed of rather young lineages, not Tertiary relicts, predominantly of European origin. Macaronesia also seems to be an important source region for back-colonisation of continental fringe regions on both sides of the Atlantic. This group of archipelagos (Azores, Madeira, Selvagens, Canary Islands, and Cabo Verde) has been crucial to learn about the particularities of macroecological patterns and interaction networks on islands, providing evidence for the development of the General Dynamic Model of oceanic island biogeography and subsequent updates. However, in addition to exceptionally high richness of endemic species, Macaronesia is also home to a growing number of threatened species, along with invasive alien plants and animals. Several innovative conservation and management actions are in place to protect its biodiversity from these and other drivers of global change. The Macaronesian Islands are a well-suited field of study for island ecology and evolution research, mostly due to its special geological layout with 40 islands grouped within five archipelagos differing in geological age, climate and isolation. A large amount of data is now available for several groups of organisms on and around many of these islands. However, continued efforts should be made toward compiling new information on their biodiversity, to pursue various fruitful research avenues and develop appropriate conservation management tools., This manuscript is a contribution by the INCT in Ecology, Evolution and Biodiversity Conservation funded by MCTIC/CNPq/FAPEG (grant 465610/2014-5)., Florencio, M.; Patiño, J.; Nogué, S.; Traveset, A.; Borges, P. A. V.; Schaefer, H.; Amorim, I. R.; Arnedo, M.; Ávila, S. P.; Cardoso, P.; de Nascimento, L.; Fernández-Palacios, J. M.; Gabriel, S. I.; Gil, A.; Gonçalve, v.; Harou, R.; Iller, J C.; López-Daria, M.; Martíne, A.; Martins, G. M.; Neto, A. I.; Nogales,M.; Oromí, P.; Rando, J. C.; Raposeiro, P. M.; Rigal, F.; Romeiras, M. M.; Silva, L.; Valido, A.; Vanderpoorten, A.; Vasconcelos, E.; Santos, A. M. C.

The Caribbean island of Carriacou is notable for its recurrent drought, paucity of large, native land animals, and well-developed bank and barrier reef system. These environmental conditions presented challenges and opportunities to the Amerindians, Europeans, and enslaved Africans who settled here through time. While available evidence suggests human presence has altered island ecology through agriculture, deforestation, erosion, species introductions, and extinction, overall human ecodynamics remain poorly understood. In 2018, the Carriacou Ecodynamics Archaeology Project (CEAP) initiated a field program investigating long-term human-environment interaction to reconstruct Carriacou’s landscape history. The CEAP seeks to develop high-resolution records for anthropogenic habitat modification and change in biotic communities from initial Amerindian settlement (ca. AD 400) through the colonial period (1740s–1974) up to the present. Pilot investigations comprising pedestrian survey, test pitting, site mapping, and geophysical survey targeted the coastal archaeological site Sabazan, where ca. 1,600 years of pre- and post-contact settlement are recorded. Here, we present the results of this first field season, demonstrating the potential of geophysical survey approaches in the Caribbean and the need for renewed, focused attention to Carriacou’s archaeological resources which are being rapidly lost due to coastal erosion.

Importance of community stakeholder participation in coastal freshwater and tidal wetland monitoring and restoration has become increasingly recognised. In Australia, Land and Sea Rangers (LSR) are appointed land and sea custodians from local indigenous communities and under guidance of experts learn a range of scientifically relevant and rigorous sampling techniques to protect and conserve Country. Scientific training to build LSR confidence to tackle restoration and conservation of sensitive and culturally important wetlands is shown here. Between May 2014 and May 2015 three training campaigns were completed where LSR on Boigu and Saibai Islands (the most northern islands in the Torres Straits, Australia), completed water quality and wetland flora/fauna surveys across both islands. Forty wetland fauna species were documented (with a similar wetland assemblage on each ANOSIM P > 0.4) comprising 35 fish species (including the invasive freshwater climbing perch, Anabas testudineus), two crustaceans, a freshwater turtle (Chelodina oblonga) (a relic freshwater species after the last sea level rise approximately 6,000 years ago in the region), and two mangrove snakes (Myron richardsoni and Fordonia leucobalia) (both snake records represent a range extension). This data was presented at community workshops with the purpose to build LSR confidence, and with the community, develop a plan to conserve wetland cultural and environmental values. Five thematic wetland conservation themes were identified which resulted in agreeing to management actions necessary on both islands. Since the inception of this program in 2014, additional LSR restoration and monitoring programs have extended to wetlands on other islands in the Torres Straits. We advocate the need for more remote area wetland monitoring and management programs facilitated through LSR programs.

Island Ecology for Educators is an interdisciplinary course that is cross-listed between environmental studies and education students engaging both undergraduate and graduate students. This chapter aims to contribute to our understanding of environmental education practices by introducing the TTIP Teaching Model addressing (1) the importance of teaching about and in nature, (2) issues of teaching in the digital age, (3) benefits derived from interdisciplinary courses, and (4) building partnerships in your community. The TTIP model is the framework that the authors developed and adapted for creating an engaging platform for learning and teaching of environmental education and blends the aspects of teaching outdoors (T), technology inclusion (T), interdisciplinary courses (I), and partnering with experts (P). The discussion includes the outcomes of the course and recommendations for how to design similar environmental education courses using the TTIP Teaching model focusing on content application, pedagogical application, technology infusion, and partnership creation.

Aim Long‐term ecological data provide a stepped frame of island ecosystem transformation after successive waves of human colonization, essential to determine conservation and management baselines. However, the timing and ecological impact of initial human settlement on many islands is still poorly known. Here, we report analyses from a 4800‐year sedimentary sequence from Gran Canaria (Canary Islands), with the goal of disentangling forest responses to natural fire from early human pressure on the island. Location La Calderilla, a volcanic maar caldera at 1,770 m a.s.l. on Gran Canaria. Taxon Plants and fungi. Methods A core from the caldera infill was analysed for sediment properties, pollen, micro‐ and macrocharcoal, with radiocarbon and biochronology dating. Fossil data were statistically zoned and interpreted with the help of cross‐correlation and ordination analyses. Surface samples and a pollen–vegetation training set were used as modern analogues for vegetation reconstruction. Results Before human settlement (4,800–2,000 cal. yr bp), pine (Pinus canariensis) pollen dominated. Extensive dry pine forests characterized the highlands, although with temporary declining phases, followed by prompt (sub‐centennial scale) recovery. Towards 2,280 cal. yr bp there was a shift to open vegetation, marked by an increase in coprophilous spores. Coincidental with independent evidence of human settlement in the pine belt (2,000–470 cal. yr bp) there was a decline of pine and a peak in charcoal. Following historic settlement (470–0 cal. yr bp), pollen producers from anthropogenic habitats, secondary vegetation and coprophilous fungi increased in abundance, reflecting higher pressure of animal husbandry and farming. Modern moss polsters reflect extensive reforestation since 1950 ce (Common Era). Main conclusions From 4,800 cal. yr bp, the pristine vegetation covering the Gran Canaria highlands was a mosaic of dry pine forests and open vegetation. The pine forests sustained intense fires, which may well have promoted habitat diversity. Human interference was initiated around 2,280 cal. yr bp probably by recurrent cultural firing and animal husbandry, triggering a steady trend of forest withdrawal and expansion of grasses and scrubs, until the final disappearance of the pine forest locally in the 20th century. Grasslands were found to be of ancient cultural origin in the summit areas of Gran Canaria, although they underwent an expansion after the Castilian Conquest.

Islands are ideal research models to study ecological processes, as they vary in size, ecological conditions, and have clearly defined boundaries. Despite great advances in island research, comprehensive understanding of numerous aspects in island ecology is still lacking. Open questions include the effects of spatial scale on island biodiversity, community assembly processes, and the diversity of species forms and functions on islands. Here, I review recent studies investigating species assembly processes and resulting diversity patterns on small islands at local and global scales. I discuss how small-island communities are shaped by environmental, population-level, and species-level processes that differ in strength with island area. Functional trait-based approaches better explained these patterns than measures of species richness on small islands. Detailed ecological understanding of community assembly processes on islands is of paramount importance to conserve biodiversity in an increasingly fragmented natural world.

Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record covering the past ~ 8,000 years from Lago di Baratz, north-west Sardinia. Vegetation and fire history are reconstructed by pollen, spores, macrofossils and charcoal analyses and environmental dynamics by high-resolution element geochemistry together with pigment analyses. During the period 8,100–7,500 cal bp, when seasonality was high and fire and erosion were frequent, Erica arborea and E. scoparia woodlands dominated the coastal landscape. Subsequently, between 7,500 and 5,500 cal bp, seasonality gradually declined and thermo-mediterranean woodlands with Pistacia and Quercus ilex partially replaced Erica communities under diminished incidence of fire. After 5,500 cal bp, evergreen oak forests expanded markedly, erosion declined and lake levels increased, likely in response to increasing (summer) moisture availability. Increased anthropogenic fire disturbance triggered shrubland expansions (e.g. Tamarix and Pistacia) around 5,000–4,500 cal bp. Subsequently around 4,000–3,500 cal bp evergreen oak-olive forests expanded massively when fire activity declined and lake productivity and anoxia reached Holocene maxima. Land-use activities during the past 4,000 years (since the Bronze Age) gradually disrupted coastal forests, but relict stands persisted under rather stable environmental conditions until ca. 200 cal bp, when agricultural activities intensified and Pinus and Eucalyptus were planted to stabilize the sand dunes. Pervasive prehistoric land-use activities since at least the Bronze Age Nuraghi period included the cultivation of Prunus, Olea europaea and Juglans regia after 3,500–3,300 cal bp, and Quercus suber after 2,500 cal bp. We conclude that restoring less flammable native Q. ilex and O. europaea forest communities would markedly reduce fire risk and erodibility compared to recent forest plantations with flammable non-native trees (e.g. Pinus, Eucalyptus) and xerophytic shrubland (e.g. Cistus, Erica).

Dokdo's high marine biodiversity has received worldwide attention recently. A total of 578 macrozoobenthos are recorded since the 1960s, but ecology of Dokdo's fauna is unknown. We monitored Dokdo's subtidal macrozoobenthos for 5 years in 2013–17, in the present study. Five stations representing three subtidal habitats were monitored; 1) oceanic plateau, 2) coastal terrace, and 3) island wharf. In total, 13,664 individuals belonging to 141 taxa were recorded during the survey. The number of species and density varied greatly among stations without distinct year-round variation. Faunal compositions significantly differed in time and space, reflecting varied faunal adaptations in a harsh environment. Whilst, temporal stability in faunal assemblages was evidenced for some dominant or cosmopolitan taxa. High spatial heterogeneity reflects site-specific oceanographic conditions. Meantime, sea-surface temperature and wave action were associated with year-round faunal compositions. Overall, the Dokdo's macrozoobenthos significantly contribute to marine biodiversity of the East Sea.

Antelope Island, situated in Great Salt Lake, Utah, is predominantly grassland (~90%), which supports a variety of organisms from grazers to predators. The island is also home to multiple freshwater springs and rocky sagebrush highlands, as well as rolling sandy dunes. Reptiles are an oft overlooked, but incredibly important, contributor of local food webs. Lizards dominate dune habitats while snakes are often observed in rocky upland habitats searching for small mammals. This chapter seeks to describe the paleogeographic history of amphibians and reptiles in the western United States generally and in Utah specifically. It is also our goal to provide context to the rich herpetological research conducted in Utah over the last 75 years that has contributed to our current understanding. This chapter will also include the species accounts for the known amphibians and reptiles inhabiting Antelope Island as well as a dichotomous key for accurate field identification. Lastly, in addition to describing how these organisms have adapted to their current habitats, we will discuss how those populations may transform as a result of a changing climate.

Island Ecology Oceanic islands are among the most recent areas on Earth to have been colonized by humans, in many cases in just the past few thousand years. Therefore, they are important laboratories for the study of human impacts on natural vegetation and biodiversity. Nogue et al. provide a quantitative palaeoecological study of 27 islands around the world, focusing on pollen records of vegetation composition before and after human arrival. The authors found a consistent pattern of acceleration of vegetation turnover after human invasion, with median rates of change increasing by a factor of six. These changes occurred regardless of geographical and ecological features of the island and show how rapidly ecosystems can change and how island ecosystems are set on new trajectories. Science , this issue p. [488][1] [1]: /lookup/doi/10.1126/science.abd6706

SUMMARYIslands are widely considered to be model systems for studying fundamental questions in ecology and evolutionary biology. The fundamental state factors that vary among island systems – geologic history, size, isolation and age – form the basis of mature phenomenological and predictive theory. In this review, we first highlight classic lines of inquiry that exemplify the historical and continuing importance of islands. We then show how the conceptual power of islands as ‘natural laboratories’ can be improved through functional classifications of both the biological properties of, and human impact on, insular systems. We highlight how global environmental change has been accentuated on islands, expressly because of their unique insular properties. We review five categories of environmental perturbation: climate change, habitat modification, direct exploitation, invasion and disease. Using an analysis of taxonomic checklists for the arthropod biotas of three well-studied island archipelagos, we show how taxonomists are meeting the challenge of biodiversity assessment before the biodiversity disappears. Our aim is to promote discussion on the tight correlations of the environmental health of insular systems to their continued importance as singular venues for discovery in ecology and evolutionary biology, as well as to their conservation significance as hotspots of endemism.

For effective and efficient pest management it is essential to understand the ecology of the target species and recipient ecosystems. The use of rodent eradication as a restoration tool is well established in temperate regions, but less common in the tropics, presenting an opportunity to undertake scientific learning in tandem with rodent eradications. On a dry tropical archipelago, we used a Before-After-Control-Impact framework to document (1) fluctuations in the abundance and demography of invasive Rattus rattus and Mus musculus on three different islands, (2) the trophic niche of all three invasive rodent populations, and (3) changes in the invertebrate community before and after rodent eradication, also comparing with two rodent free islands. While rat density was high and relatively stable throughout the year, the two mouse populations greatly differed in body size and seasonal dynamics, despite their proximity. The rodents in all three populations were generalist and opportunistic feeders, although stable isotope analyses results indicated major differences among them, driven by food availability and rodent species. Seasonal fluctuations in invertebrate communities depended on rodent invasion status, but recovery in the invertebrate communities one year after rodent removal was limited for all islands. Predictions for other tropical ecosystem biomes require long-term research on more tropical islands. Improving our understanding of island and species-specific contexts of rodent eradications can advance island restoration projects and assist the selection of indicator species for ecosystem recovery.

Herbaceous plants are widely distributed on islands and where they exhibit spatial heterogeneity. Accurately identifying the impact factors that drive spatial heterogeneity can reveal typical island biodiversity patterns. Five southern islands in the Miaodao Archipelago, North China were studied herein. The spatial distribution of herbaceous plant diversity on these islands was analyzed, and the impact factors and their degree of impact on spatial heterogeneity were identified using CCA ordination and ANOVA. The results reveal 114 herbaceous plant species, belonging to 94 genera from 34 families in the 50 plots sampled. The total species numbers on different islands were significantly positively correlated with island area, and the average α diversity was correlated with human activities, while the β diversity among islands was more affected by island area than mutual distances. Spatial heterogeneity within islands indicated that the diversities were generally high in areas with higher altitude, slope, total nitrogen, total carbon, and canopy density, and lower moisture content, pH, total phosphorus, total potassium, and aspect. Among the environmental factors, pH, canopy density, total K, total P, moisture content, altitude, and slope had significant gross effects, but only canopy density exhibited a significant net effect. Terrain affected diversity by restricting plantation, plantation in turn influenced soil properties and the two together affected diversity. Therefore, plantation was ultimately the fundamental driving factor for spatial heterogeneity in herbaceous plant diversity on the five islands.

Stable carbon and nitrogen isotopes are used to address the dietary relationship between humans and two canid species at the Uyak site (KOD-145) on Kodiak Island, Alaska: dog (Canis familiaris) and red fox (Vulpes vulpes). We assess the relative contribution of marine and terrestrial protein to each species’ diet as a measure of their dietary relationship to people, using zooarchaeological data, food web data, and ethnohistoric observations to interpret the results. The results suggest that dogs and foxes had different diets: the dogs are consistently enriched in both 13C and 15N, which indicates a heavy dependence on marine protein, while the fox samples produced both marine and terrestrial isotope values. Data from this project have the potential to expand our understanding of human-canid relationships in this island environment and in the greater context of island ecology, and contribute some of the first isotopic data for small terrestrial mammals in the Gulf of Alaska.

Aim: We undertook the largest comparative study to date of the form of the island species–area relationship (ISAR) using 207 habitat island datasets and 601 true island datasets. We also undertook analyses of (a) the factors influencing z‐ and c‐values of the power (log–log) model and (b) how z and c vary between different island types. Location:Global. Methods: We used an information theoretic approach to compare the fit of 20 ISAR models to 207 habitat island datasets. Model performance was ranked according to pre‐set criteria, including metrics of generality and efficiency. We also fitted the power (log–log) model to each dataset and analysed variation in parameter estimates and model fits as a function of key dataset characteristics using linear models and constrained analysis of principal coordinates. Results: The power (nonlinear) model provided the best fit to the most datasets, and was the highest ranked model overall. In general, the more complex models performed badly. Average z‐values were significantly lower for habitat island datasets than for true islands, and were higher for mountaintop and urban habitat islands than for other habitat island types. Average c‐values were significantly lower for oceanic islands, and significantly higher for inland water‐body islands, than for habitat islands. Values of z and c were related to dataset characteristics including the ratio of the largest to smallest island and the maximum and minimum richness values in a dataset. Main conclusions: Our multimodel comparisons demonstrated the nonlinear implementation of the power model to be the best overall model and thus to be a sensible choice for general use. As the z‐value of the log–log power model varied in relation to ecological and geographical properties of the study systems, caution should be employed when using canonical values for applied purposes.

Islands face increasingly prominent environmental problems with rapid urbanization. Hence, timely and objective monitoring and evaluation of island ecology is of great significance. This study took the Pingtan Comprehensive Experimental Zone (PZ) in the east sea of Fujian Province of China as the research object. Based on remote sensing technology, four Landsat images from 2007 to 2017 and the remote sensing ecological index (RSEI) were used to explore the ecological status and space&ndash, time change. The results showed that from 2007 to 2011, the average RSEI decreased from 0.519 to 0.506, indicating that the ecological quality generally showed a slight downward trend, mainly due to large-scale development brought by the construction, by 2014, although the ecology of the original area improved, the overall ecology was still declining with 0.502 mean RSEI mainly because of large-scale reclamation projects, by 2017, the average RSEI rebounded to 0.523, which was attributed to the fact that ecological construction and protection were emphasized in the construction of PZ, especially in reclamation areas. In conclusion, the increase of large area bare soil will lead to the decline of regional ecology, but the implementation of scientific ecological planning is conducive to ecological restoration and construction.

© 2017 The Authors., [Aim] Rarity—an important measure for conservation biogeography—can vary over many orders of magnitude. However, it is unclear which regional-scale abiotic conditions drive processes affecting rarity of endemic species on islands. To support conservation efforts, we (1) assess the main abiotic drivers of endemic rarity, (2) determine how well existing protected areas (PAs) coincide with hotspots of endemic rarity and (3) introduce and evaluate a new hypervolume-based rarity estimator., [Location] La Palma (Canary Islands)., [Methods] We recorded all present endemic vascular plant species in 1,212 plots covering the entire island. We calculated endemic rarity (corrected range-rarity richness for endemics) using a rarity estimation approach based on kernel density estimations (hypervolume approach). We performed a sensitivity analysis based on multiple linear regressions and relative importance estimations of environmental drivers to estimate the performance of the hypervolume-based rarity estimation compared to standard methods (occurrence frequency, convex hulls, alpha hulls)., [Results] Climate variables (mean annual temperature, climatic rarity, precipitation variability) best explained archipelago endemic (AE) and single-island endemic (SIE) rarity. Existing PAs covered the majority of AE and SIE rarity, especially national and natural parks as well as the Natura 2000 sites. In our study system, hypervolumes performed better than standard measures of range size., [Main conclusion] Both AE and SIE rarity on La Palma show a clear spatial pattern, with hotspots of endemic rarity found at high elevations and in rare climates, presumably owing to geographical and climatic constraints and possibly anthropogenic pressure (e.g., land use, introduced herbivores, fire). Areas of high rarity estimates coincide with the distribution and extent of PAs on La Palma, especially since the recent addition of the Natura 2000 sites. The hypervolume approach is a promising tool to estimate species range sizes, and can be applied on all scales where point/plot data are available., This work contributed to and was partially supported by the European H2020 Project 641762 ECOPOTENTIAL: Improving future ecosystem benefits through Earth Observations.

The Pilbara Coast, in NW Australia, stands unique as the most geologically/geomorphologically diverse arid coast globally and, as such, it is a coastline of Global Significance. Ideally, it should have been listed as a site of World Heritage. While there are a variety of coastal forms along the Pilbara Coast, a ubiquitous feature of the region is the development of extensive salt flats landward of mangrove-fringed coastlines, and leeward of barrier limestone ridges and barrier dunes. The aridity of the Pilbara Coast and the occurrence of extensive salt flats lend themselves to exploitation for development of solar salt production ponds but this has resulted in the destruction of unique coastal geomorphology, salt flat habitats, 'sand island ecology' and the natural diagenesis of arid-zone coastal geology. This contribution explores the significance of solar salt pond development along a globally unique coastline, and highlights that there needs to be a component of geoethics in government decision-making that considers all the values of a site.

Seed dispersal and seedling recruitment are crucial phases in the life cycle of all spermatophyte plants. The net contribution of seed dispersers to plant establishment is known as seed dispersal effectiveness (SDE) and is defined as the product of a quantitative (number of seeds dispersed) and a qualitative (probability of recruitment) component. In Galápagos, we studied the direct contribution to SDE (number of seeds dispersed and effect on seedling emergence) provided by the five island groups of frugivores (giant tortoises, lizards, medium-sized passerine birds, small non-finch passerine birds, and finches) in the two main habitats in this archipelago: the lowland and the highland zones, and found 16 vertebrate species dispersing 58 plant species. Data on frequency of occurrence of seeds in droppings and number of seeds dispersed per unit area produced contrasting patterns of seed dispersal. Based on the former, giant tortoises and medium-sized passerines were the most important seed dispersers. However, based on the latter, small non-finch passerines were the most important dispersers, followed by finches and medium-sized passerines. The effect of disperser gut passage on seedling emergence varied greatly depending on both the disperser and the plant species. Although the contribution to SDE provided by different disperser guilds changed across plant species, medium-sized passerines (e.g., mockingbirds) provided a higher contribution to SDE than lava lizards in 10 out of 16 plant species analysed, whereas lava lizards provided a higher contribution to SDE than birds in five plant species. While both the quantitative and qualitative components addressed are important, our data suggests that the former is a better predictor of SDE in the Galápagos archipelago.

The first human populations colonized the Bismarck Archipelago about 40,000 years ago. The zooarchaeological evidence from Buang Merabak (New Ireland) reveals that, at a first stage, hunter-gatherers only focused on the exploitation of local faunal resources, especially cave-dwelling bats and varanids. As for other Pleistocene assemblages, the contribution of fish to the diet is negligible. Introduced species appear since about 23,050 cal bp with the northern common cuscus (endemic of New Guinea), although bats still provided most of the meat consumed at the site. In later times, the cuscus dominates the assemblage, partially replacing cave-dwelling bats, and the wallaby is also introduced from New Guinea. The introduction and increasing consumption of the cuscus had major implications in terms of land use and mobility. The initial focus on cave-dwelling bats implied shorter stays at sites and required constant movements through the landscape; the shift towards cuscus consumption reduced mobility.

Everglades tree islands are patches of woody vegetation ranging in size from 0.1 to 70 ha embedded in a marsh matrix. Tree islands are an essential component of the tree island–ridge–slough topographic continuum and the trees provide a mechanism for the accumulation of phosphorus in the landscape, enhancing landscape biocomplexity. This article reviews the literature of tree island ecology and describes the predicted effects of five ecosystem restoration scenarios on tree islands. Elevations of the highest points on 404 islands across the Everglades were used to assess the effects of the scenarios at a landscape level, while the plant communities of nine islands were modeled to assess local effects. Evaluation of the restoration scenarios were based on three critical components needed to maintain and restore tree islands: hydrology that allows the survival of woody species, seasonally appropriate water flow to move nutrients off the heads of islands, and oligotrophy. All restoration options generally improved water conditions for tree growth, although flooding of islands in some areas was predicted to increase. Scenarios with the greatest amount of decompartmentalization and largest capacity to remove phosphorus from water entering the Everglades provided the best chance of delivering vigorous pulses of sheet flow in directions parallel to historic flows and maintaining oligotrophy. Tree islands are “bellwethers” of restoration actions because their maintenance on the landscape requires multiple ecosystem functions.

In recent years, China’s island ecology has been destroyed seriously, so ecological recovery of islands is an urgent task. Qiaoliangshan Island is a typical island in China that suffers from ecological problems after land ecology is destroyed by human beings. This paper introduces general situation of Qiaoliangshan Island, researches on species selection for vegetation ecological recovery on Qiaoliangshan Island and aims to provide a reference for ecological recovery of Chinese islands.

This paper documents the first 10,000 year old plant macrofossil record of vegetation changes on the central island of Santa Cruz, providing information on Sphagnum bog vegetation patterns, local extinction of key taxa, and temporal successions in the Galápagos humid highlands. Vegetation change is reconstructed through examination of Holocene sedimentary sequences obtained from three Sphagnum bogs located within volcanic caldera forming the high elevation central ridge system of Santa Cruz Island. Results indicate that these specialized Sphagnum bog ecosystems are dynamic and have undergone considerable changes in vegetation composition, transitioning from diverse hygrophilous herbs and submerged aquatic ecosystems to drier Sphagnum/. Pteridium bog systems, during the last 10,000 cal yr BP. Additionally a new aquatic genus previously undocumented on the islands, Elatine, was discovered at two of the study sites, but it is now extinct on the archipelago. Some of the observed vegetation successions may have been driven by climatic shifts occurring within the eastern equatorial Pacific (EEP). Other drivers including anthropogenic change are also considered significant over the last hundred years, placing strain on this naturally dynamic system. This study helps reveal patterns of change in the humid highlands over the last 10,000 cal yr BP regarding vegetation variability, climatic shifts, the historical influence of fire, tortoise disturbance, and recent anthropogenic impacts on the island. © 2012 Elsevier Ltd.

Explanations for the extinction of Late Quaternary megafauna are heavily debated, ranging from human overkill to climate change, disease and extraterrestrial impacts. Synthesis and analysis of Late Quaternary animal extinctions on California's Channel Islands suggest that, despite supporting Native American populations for some 13,000 years, few mammal, bird or other species are known to have gone extinct during the prehistoric human era, and most of these coexisted with humans for several millennia. Our analysis provides insight into the nature and variability of Quaternary extinctions on islands and a broader context for understanding ancient extinctions in North America.

Long-term ecological studies are critical for providing key insights in ecology, environmental change, natural resource management and biodiversity conservation. However, island fire ecology is poorly understood. No previous studies are available that analyze vegetative changes in burned and unburned dry forest remnants on Wa'ahila Ridge, Hawai'i. This study investigates vegetation succession from 2008 to 2015, following a fire in 2007 which caused significant differences in species richness, plant density, and the frequency of woody, herb, grass, and lichens between burned and unburned sites. These findings infer that introduced plants have better competitive ability to occupy open canopy lands than native plants after fire. This study also illustrates the essential management need to prevent alien plant invasion, and to restore the native vegetation in lowland areas of the Hawaiian Islands by removing invasive species out-planting native plants after fire. Language: en

13 pages, 4 figures, 3 tables.-- Available online Nov 28, 2008., The diet of feral cats in the main habitats of the Canary Islands is composed of introduced mammals, birds, reptiles and insects. However, introduced mammals constitute the main source of biomass consumed, followed in importance by reptiles and birds. PCA analysis of biomass revealed the ordination of three different groups, corresponding to the diet in the laurel forest (La Gomera), thermophilous forest (El Hierro) and one large group that include the rest of habitat types. A similar pattern was observed when these habitats were analyzed in a single island (La Palma). Oryctolagus cuniculus was an important prey in practically all habitats, while Rattus rattus was frequently captured in the laurel forest, Mus musculus domesticus in the open shrubs (both xeric and high mountain), reptiles (mainly lizards genus Gallotia) in the open habitats of Tenerife, birds play a relative role in forest habitats, and large invertebrates (basically Orthoptera and Coleoptera) in the three forest habitats and in the xerophytic shrub of Fuerteventura. Morisita's index of similarity of diet showed maximum differences between the forest habitats (pine and thermophilous vs. laurel forest), indicating an important heterogeneity in the diet of feral cats in these environments. Shrub habitats showed smaller values of Levin's niche breadth than those from the forest habitats, showing a broader diet in the latter. Lastly, the diet of feral cats on the Canary Islands follows the general pattern of other islands located at similar latitude and mainly composed by rabbits and mice. However, specific preys such as lizards, rats or birds, play an important role in particular habitats in which they are abundant., This contribution has been carried out during the Project GL2004-04884-C02-01/BOS financed by the Spanish Ministry of Science and the European Union.

Tropical island species and ecosystems are threatened worldwide as a result of increasing human pressure. Yet some of these islands also lend themselves to restoration, as they are physically defined units that can be given focused attention, as long as resources are available and clear conservation targets are set. Cousine Island, Seychelles, is a tropical island that has received such intensive restoration. From a highly degraded island in the 1960s, the island has now been restored to what is believed to be a semblance of the natural state. All alien vertebrates have been eradicated, as have 25 invasive alien plants. Cultivated plants are now confined to one small section of the island. Poaching of nesting marine turtles has been stopped, leading to an increase in turtle breeding numbers. The shearwater population has increased in size with poaching activities under control. The Sooty tern has also returned to the island to breed. The coastal plain has been restored with over 2,500 indigenous shrubs and trees, which have now grown into a forest carpet. There are strict quarantine procedures on the island, keeping it free of rats, mice, various alien invertebrates and potentially invasive alien plants. Three threatened Seychelles endemic land birds (Seychelles warbler, Seychelles magpie robin and Seychelles white-eye) have been introduced and are thriving, with these introductions contributing to both the magpie robin and the white-eye being downgraded from CR to EN (the warbler remains at VU). Ecotourism, and nature conservation for the local inhabitants, have been introduced in a way that does not reduce the improved compositional, structural and functional biodiversity of the island. The result of the restoration effort appears to be sustainable in the long term, although challenges still remain, especially with regards to adequate clean water and a non-polluting power supply on the island. Cousine is thus paving the way in the art and science of tropical island restoration as a legacy for future generations.

Aim To investigate the chronology, causes and consequences of the extinction of the autochthonous Pleistocene small mammals of Mallorca. Location Mallorca (Gymnesic Islands, Balearics, Western Mediterranean). Methods We have obtained the first direct 14C ages from the bone collagen of selected samples of two extinct endemic small mammals from Mallorca: the Balearic dormouse, Eliomys morpheus (Rodentia: Myoxidae) and the Balearic shrew, Asoriculus hidalgoi (Soricomorpha: Soricidae). We also present evidence for the absence of both endemics from the earliest Mallorcan archaeological sites and for the introduction of the garden dormouse, Eliomys quercinus, and the wood mouse, Apodemus sylvaticus. Combined information from direct dating of bone collagen of E. quercinus and A. sylvaticus and from cultural associations provides an adequate framework to establish the chronology of the faunal change and to compare it with the chronological information available on climatic change and the first arrival of humans on the islands. Results The chronological record includes the latest evidence available for the survival of endemic species and the earliest introduction of small mammals into Mallorca. We present ‘uncertainty periods for extinction’ (UPEs) of both endemic mammals based on the chronology of their last occurrence and on the inferred timing of their extinction (restricted UPEs). Main conclusions Possible causes for the extinction of autochthonous small mammals on Mallorca are discussed. Once we have discarded climatic causes, predation by invasive species, competition with newcomers and habitat deterioration, the introduction of diseases emerges as the most reasonable explanation for these extinctions. Based on the identification of changes in keystone species in Mallorcan ecosystems, we propose a tentative schedule of key ecological changes that have taken place over the past 5 millennia.

Climate and topography are among the most fundamental drivers of plant diversity. Here, we assessed the importance of climate and topography in explaining diversity patterns of species richness, endemic richness and endemicity on the landscape scale of an oceanic island and evaluated the independent contribution of climatic and topographic variables to spatial diversity patterns. 2. We constructed a presence/absence matrix of perennial endemic and native vascular plant species (including subspecies) in 890 plots on the environmentally very heterogeneous island of La Palma, Canary Islands. Species richness, endemic richness and endemicity were recorded, interpolated and related to climate (i.e. variables describing temperature, precipitation, variability and climatic rarity) and topography (i.e. topographic complexity, solar radiation, geologic age, slope and aspect). We used multimodel inference, spatial autoregressive models, variance partitioning and linear regression kriging as statistical methods. 3. Species richness is best explained by both climatic and topographic variables. Topographic variables (esp. topographic complexity and solar radiation) explain endemic richness, and climatic variables (esp. elevation/temperature and rainfall seasonality) explain endemicity. Spatial patterns of species richness, endemic richness and endemicity were in part geographically decoupled from each other. 4. Synthesis. We identified several topography-dependent processes ranging from evolutionary processes (micro-refugia, in situ speciation, pre-adaptation to rupicolous conditions, dispersal limitations) to human-induced influences (introduced herbivores, fire, land use) that possibly shape the endemic richness pattern of La Palma. In contrast, climate mainly drives endemicity, which is connected to ecological speciation and specialization to local conditions. We highlight the importance of incorporating climatic variability into future studies of plant species diversity and endemism. The spatial incongruence in hot spots of species richness, endemic richness and endemicity emphasizes the need for an integrated conservation approach acknowledging different diversity measures to protect the complete spectrum of diversity. High-elevation islands such as La Palma are highly suitable to study drivers of diversity and endemism, as they offer environmental gradients of continental magnitude on the landscape scale of a single climatic mini-continent and a large array of in situspeciated endemics.

Copyright by the Ecological Society of America, Seed dispersal effectiveness (SDE) is the contribution of dispersers to plant recruitment and is estimated as the product of the number of seeds dispersed (quantity) and the probability of recruitment of each dispersed seed (quality). Although SDE is a key concept in seed dispersal ecology, few studies estimate SDE and none has a community approach. Oceanic islands, with simple communities, are ideal for this purpose. In this study, we compared the SDE of the main types of dispersers (lizards and passerine birds) at the community level in a given habitat. We estimated SDE using a stochastic simulation model parameterized with empirical data on quantity and quality components measured throughout the recruitment process. Although lizards are highly frugivorous and their density was ~20 times higher than that of birds, lizards and birds dispersed a similar quantity of seeds. This may be due to lower intake of seeds by lizards due to their slower metabolism (~20 times lower than birds). This low metabolic rate limits the importance of lizards as seed dispersers, but it is compensated by extraordinarily high lizard densities in the study area (~9600 individuals/km2). High densities of lizards are typical of islands, and this helps to explain why dispersal by lizards seems mainly an island phenomenon. Birds and lizards showed functional complementarity, especially regarding seed dispersal distribution patterns. In fact, lizards dispersed more seeds in shrublands and open sites, and birds in woodlands and beneath canopies, with their joint contribution helping to maximize recruitment. Lizards provided higher SDE than birds for 7 out of 11 plant species. The disperser with a higher quantity for a given plant generally had the higher quality, and plants could be classified as bird- or lizard-dependent for dispersal. This dependence increased when considering SDE instead of dispersal quantity only. Moreover, quality was a better predictor of SDE than quantity, which should be considered when parameterizing interaction networks, as this might affect inferences about their architecture., This work was financed by the Spanish Ministry of Science and Education project (CGL2007-61165/BOS), supported by FEDER funds from the European Union.

Marine islands harbour a great part of our planet’s biological diversity and a high proportion of endemic species. However, island biota are particularly susceptible to anthropogenic threats like climate change, habitat loss and species invasions, making a detailed understanding of ecological processes on islands imperative if we wish to conserve their unique biotas. Due to their discrete and isolated nature, islands are useful model systems in ecological and evolutionary research. So far, however, most studies have concentrated on small-scale biogeographic patterns, and standardized global data on island biogeographic characteristics as well as a macroecological synthesis of their biotas are currently lacking. In this thesis, I provide a physical and bioclimatic characterization of the world’s islands and address the question of how abiotic island characteristics affect the diversity of island floras. I tackle two major aspects of this question: First, I investigate past and present bioclimatic and physical island characteristics as drivers of island plant diversity patterns, focusing on the spatial arrangement of islands and structure of archipelagos. Second, I investigate taxon-specific and trait-related differences in the response of plant diversity patterns to abiotic factors on islands. I present a database of past and present bioclimatic and physical characteristics including island area, isolation and geology for 17,883 islands larger than 1 km² worldwide. Using ordination and clustering techniques, I characterize and classify the islands in multidimensional environmental space. I also develop a set of ecologically meaningful metrics of island isolation and of the spatial arrangement of islands in archipelagic settings, including metrics related to stepping stones, wind and ocean currents, climatic similarity, inter-island distances and surrounding landmass area. These metrics account for different aspects of island isolation that influence immigration, in situ speciation and extinction on islands and turnover among islands. To link abiotic characteristics of islands to biotic attributes of island floras, I use a database of 1,295 island species checklists including c. 45,000 native vascular plant species, compiled for this thesis. It is the first global and most comprehensive dataset on island plant diversity, including species identities instead of mere species numbers. The global island characterization quantitatively confirms that islands differ from mainland areas in their bioclimatic and physical characteristics. Islands are, on average, significantly cooler, wetter and less seasonal than mainlands. I show that a thorough circumscription of the physical and spatial characteristics of islands and archipelagos, especially isolation, archipelago structure and scale, is needed to understand diversity patterns of their biotas. Isolation is the second most important factor after area determining vascular plant species richness on islands. Among the compared isolation metrics, the proportion of surrounding land area serves best for explaining vascular plant species richness. Also, accounting for stepping stones, large islands as source landmasses and climatic similarity of source areas increases the explanatory power of models compared to considering only the commonly used distance to the nearest mainland. Isolation is less important on large islands where in situ diversification counteracts the negative effect of isolation on immigration. At archipelagic scales, the intra-archipelagic spatial structure is particularly important for β diversity, i.e. species turnover among islands, and, indirectly through β, for γ diversity, i.e. the species richness of the entire archipelago. These findings highlight the importance of the spatial location of islands relative to each other for insular diversity patterns and indicate the necessity of considering islands in an archipelagic context in island research and conservation. For ferns on Southeast Asian islands, I show that the importance of physical island characteristics for diversity gradually decreases with spatial grain size from island level to plot level, where local environmental conditions are more important. Local communities may often be saturated, limiting the number of species that can immigrate from the regional species pool. To make predictions about local diversity on islands it is hence important to take the scale-dependence of species pool effects into account. Major plant groups differ in their dispersal abilities, levels of gene flow, speciation rates and adaptations to climate. Accordingly, comparative analyses among taxonomic plant groups reveal clear differences among taxa in the responses of species richness and phylogenetic diversity patterns to abiotic factors. I find varying island species-area relationships (SPARs), i.e. rates of increase in species richness with island area, among groups. The slope of SPARs is higher in spermatophytes than in pteridophytes and bryophytes, whereas the intercept is lower. In combination, phylogenetic trait and niche conservatism, environmental and dispersal filtering mechanisms and in situ speciation are expected lead to phylogenetically clustered assemblages. I show that physical and bioclimatic island attributes, linked to filtering and speciation, influence the phylogenetic structure and diversity of island floras. The strengths and directions of the relationships vary among taxonomic groups. Abiotic predictors explain more variation in phylogenetic diversity and structure for angiosperms and palms than for ferns, which is in accordance with the high dispersal ability and large range sizes of fern species. The abiotic characterization and regionalization of the world’s islands I present and the accompanying data should facilitate a more integrative consideration of islands in macroecological research. In this thesis, I provide the first predictions of insular vascular plant species richness and analyses of different diversity components (α, β, γ and phylogenetic diversity) of insular systems and their abiotic drivers at a global scale. I show that relationships between environmental drivers and species richness as well as phylogenetic assemblage attributes vary among taxonomic groups in dependence on their predominant dispersal and speciation-related characteristics. This is a new perspective in macroecological island research allowing inferences about the mechanisms underlying patterns of island plant diversity. Furthermore, understanding how the diversity of insular plant groups is shaped by immigration and diversification should promote our understanding of global diversity patterns in general.

Made available in DSpace on 2015-10-21T13:12:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-07 Aarhus University Research Foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Danish Research Council FNU Although species and their interactions in unison represent biodiversity and all the ecological and evolutionary processes associated with life, biotic interactions have, contrary to species, rarely been integrated into the concepts of spatial beta-diversity. Here, we examine beta-diversity of ecological networks by using pollination networks sampled across the Canary Islands. We show that adjacent and distant communities are more and less similar, respectively, in their composition of plants, pollinators and interactions than expected from random distributions. We further show that replacement of species is the major driver of interaction turnover and that this contribution increases with distance. Finally, we quantify that species-specific partner compositions (here called partner fidelity) deviate from random partner use, but vary as a result of ecological and geographical variables. In particular, breakdown of partner fidelity was facilitated by increasing geographical distance, changing abundances and changing linkage levels, but was not related to the geographical distribution of the species. This highlights the importance of space when comparing communities of interacting species and may stimulate a rethinking of the spatial interpretation of interaction networks. Moreover, geographical interaction dynamics and its causes are important in our efforts to anticipate effects of large-scale changes, such as anthropogenic disturbances. Aarhus Univ, Dept Biosci, Aarhus, Denmark Aalborg Univ, Dept Chem &Biosci, Aalborg, Denmark CSIC, Integrat Ecol Grp, Estn Biol Donana, E-41080 Seville, Spain Univ Estadual Paulista UNESP, Lab Fenol, Dept Bot, Sao Paulo, Brazil Departamento de Botânica, Laboratório de Fenologia, Universidade Estadual Paulista (UNESP), Rio Claro, São Paulo, Brazil FAPESP: 2011/22635-2 FAPESP: 2014/01594-4

As evidence mounts that sea levels are rising, it becomes increasingly important to understand the role of ocean water within terrestrial ecosystem dynamics. Coastal sand dunes are ecosystems that occur on the interface of land and sea. They are classic ecotones characterized by zonal distribution of vegetation in response to strong gradients of environmental factors from the ocean to the inland. Despite the proximity of the dune ecosystem to the ocean, it is generally assumed that all vegetation utilizes only freshwater and that water sources do not change across the ecotone. Evidence of ocean water uptake by vegetation would redefine the traditional interpretation of plant-water relations in the dune ecosystem and offer new ideas for assessing maritime influences on function and spatial distribution of plants across the dune. The purpose of this study was to identify sources of water (ocean, ground, and rain) taken up by vegetation using isotopic analysis of stem water and to evaluate water uptake patterns at the community level based on the distribution and assemblage of species. Three coastal dune systems located in southern Florida, USA, and the Bahamian bank/platform system were investigated. Plant distributions across the dune were zonal for 61-94% of the 18 most abundant species at each site. Species with their highest frequency on the fore dune (nearest the ocean) indicate ocean water uptake as evidenced by delta 18O values of stem water. In contrast, species most frequent in the back dune show no evidence of ocean water uptake. Analysis of species not grouped by frequency, but instead sampled along a transect from the ocean toward the inland, indicates that individuals from the vegetation assemblage closest to the ocean had a mixed water-harvesting strategy characterized by plants that may utilize ocean, ground-, and/or rainwater. In contrast, the inland vegetation relies mostly on rainwater. Our results show evidence supporting ocean water use by dune vegetation and demonstrate an exciting relationship between seawater and ecotonal shifts in plant function of a terrestrial ecosystem.

A first study of the ants on the three main islands of the Juan Fernandez Archipelago (Chile) has revealed the presence of just three species, Hypoponera confinis, Linepithema humile, and Tetramorium bicarinatum, all widely distributed invasive species. Most notable among them is the Argentine ant, L. humile, an ecologically destructive species that has established several populations and appears to be expanding. Fil: Ingram, Krista K.. University of Stanford; Estados Unidos Fil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Cover, Stefan. Harvard University; Estados Unidos Fil: Wilson, Edward O.. Harvard University; Estados Unidos

Based on field interviews in Singapore in 1985, 1997, and 2003, this article addresses the issue of how island ecology helps explain the remarkable low rates of crime that are often attributed mainly to cultural and government policies. Understanding crime and control on this most densely populated Southeast Asian atoll must begin with how people are dispersed over the limited spatial area. Ecology also influences how styles of some crimes are defined and controlled. Several of Donald Black’s propositions are given further consideration.

Abundance of floor-dwelling frogs was studied in the humid subtropical lowland forest of Iriomote Island, the Ryukyu Archipelago, southern Japan. Field survey was conducted monthly for 1 y, and the seasonal pattern of abundance was examined for each species. We observed 251 frogs belonging to four species of three families in a total sampling of 600 m2. Of these species, Microhyla ornata (66.5% of total frogs) and Fejervarya limnocharis (30.3%) were dominant in number. Total abundance of the frogs was strongly seasonal and peaked in the hottest month, August, while the number of frog species was one to three throughout the year. The seasonal pattern of abundance showed considerable variation among species, most likely due to their differences in reproductive season, and in physiological characteristics under the influence of varying temperature and rainfall. These patterns are more similar to those of temperate species than those of tropical species. The estimated density of all frogs ranged from 0.08 to 1.60 individuals m−1, and their average annual density and biomass were 4180 individuals ha−1 and 11460 g ha−1, respectively. These values, among the highest so far reported for floor-dwelling anurans, may be a feature of amphibian fauna in the humid subtropical forests on a small island.

Island archaeology is a well-established and increasingly active field of the wider discipline. Most studies, however, draw solely upon Pacific and Mediterranean examples, with Africa’s islands correspondingly neglected. This paper reviews previous archaeological work on Africa’s islands and asks what could be obtained from more systematic research on them. Several themes are identified, to all of which a comparative archaeology of Africa’s islands could contribute: patterns of colonisation and abandonment; transformations of island ecology wrought by human settlement; the role of islands in systems of international trade; the establishment of plantation economies; and the constitution and development of distinctive island cultures. Emphasis is also placed on the contribution that such a comparative archaeology could make to island archaeology as a whole and to enhancing the global profile of Africanist archaeological research.

Aims To test a new concept for island ecology and metapopulation studies: if population persistence is a result of colonization and extinction processes, one would expect remarkable variability in the age of neighbouring populations – there would be both old and young (recently established) populations. Location The lake Mamry archipelago, Poland. Methods Forty trap transects with a total of 114 Barber traps were operating from June to September in 1997 and in 1998. The traps (0.5-L plastic beakers, mouth diameter 120 mm, with a 20 × 20 cm wooden roof) were placed by applying a stratified sampling design into 13 habitat types on the 16 islands and two mainland sites. The frequency of macropterous individuals in wing-dimorphic populations of three carabid species (Pterostichus melanarius, P. anthracinus and Carabus granulatus) was used as an indicator of population ‘age’. Results The frequency of macropterous individuals in the populations varied from 0% to 100% for P. melanarius (18.5% on average), from 0% to 91% for P. anthracinus (12.6%) and from 0% to 29% for C. granulatus (8.9%). Populations hosted more long-winged individuals (and were therefore interpreted as being younger) on smaller islands, compared with those inhabiting large islands and the mainland sites. The results also revealed that the viability of the populations of the autumn-breeding P. melanarius might be more affected by population size than that of the two studied spring breeders. Island connectivity did not have a significant effect on the frequency of macropterous individuals in the studied populations. Main conclusions The inverse relationship between the proportion of macropterous individuals and island size contrasts with the accepted theory of dispersal, which assumes that there is selection against dispersal on small islands. A regression analysis for population age and habitat characteristics reveals the extinction probability of a given population. I suggest that investigations based on variability in population age can help in studies of colonization–extinction processes that would otherwise face logistic and methodological obstacles.