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The Cyclades Islands (Aegean Sea, Greece) are part of the Mediterranean Basin biodiversity hotspot and harbor a plethora of endemic species. Plant communities on the smaller islands in this region have largely evolved in the absence of herbivory and frequently lack antiherbivore defenses. This study evaluates the short- and long-term effects of the European rabbit (Oryctolagus cuniculus), an herbivore that has been released on numerous islands in the region, by comparing islands that 1. have historically been rabbit-free (ungrazed); 2. are currently grazed by rabbits, and 3. have previously been grazed, but are now rabbit-free. Ecological impacts of rabbits on the Aegean Islands were investigated by assessing the abundance, composition, and diversity of plant and arthropod communities as well as soil characteristics. Our results indicate that ungrazed islands have more arthropod species, more specialized or endemic plant species, and less exposed soil than currently grazed islands. While ungrazed islands did not necessarily possess higher total plant species richness, they did harbor significantly more small-island endemic taxa relative to presently grazed islands. This study indicates that native plant communities on Mediterranean islets are not adapted to the presence of this introduced species and that the practice of intentionally releasing rabbits on islands has significant and lasting negative ecological impacts, especially on small islands. While a complete recovery of post-rabbit was not evident over the time span of our research, both arthropod and plant data indicate that partial recovery is possible once rabbits have been removed.

Island forests are becoming increasingly fragmented and colonized by invasive species, which can eventually lead to local species extinctions. In the Galapagos Islands, invasive species pose a serious extinction threat to the endemic daisy tree Scalesia pedunculata , formerly the dominant habitat-forming species of the unique Scalesia forest. This forest has been reduced to fragments due to land use changes in the past and is now increasingly invaded by introduced plants. We conducted a field experiment on Santa Cruz Island to assess the impacts of blackberry ( Rubus niveus ) and two other invasive plant species, Cestrum auriculatum and Tradescantia fluminensis , as well as the effects of the removal of two of these ( R. niveus and C. auriculatum ) on cover, composition and diversity of the resident plant communities. Particular attention was paid to effects of the invasive species on the S. pedunculata population. Annual vegetation monitoring was carried out in a total of 34 permanent plots (10 m × 10 m) over 10 years (2014–2023), using the line-intercept method. Seventeen of these plots were established in an invaded area and 17 plots in an area with continuous invasive plant removal since 2014. Results indicated that there were significant changes in both the species composition of the plant communities and average percent cover of species over time, comparing removal plots with invaded plots. Species composition in removal plots changed significantly more than in invaded plots, towards a plant community with greater percent cover of endemic species. A significant negative relationship between the three invasive species and cover of S. pedunculata suggested that multiple invader species may have additive negative impacts. Natural recruitment of S. pedunculata by seeds was observed in the removal but not in the invaded plots. These results, as well as the striking decrease of 71% in cover of adult S. pedunculata in the invaded plots indicate that this threatened species will be driven to local extinction on Santa Cruz Island, Galapagos, in less than 20 years if invasive plant species are not removed on a large scale.

Here I examine the overexploitation of Artemisia granatensis, a narrow endemic medicinal plant species from Sierra Nevada, Spain, and the consequences for its conservation. With over 50,000 flowering plant species used for medicinal purposes worldwide, many species face sustainability issues due to overharvesting and habitat loss. Historical documentation of A. granatensis use dates back to the 13th century, highlighting its significance in traditional medicine. However, this species has suffered extensive overexploitation, particularly in the 19th and 20th centuries, leading to a significant decline in populations. Conservation concerns were first raised in 1909, and despite the species being legally protected since 1982, illegal collection and environmental pressures persist. Today, A. granatensis is critically endangered, with fewer than 2000 individuals remaining in fragmented populations. The study synthesizes the historical and recent literature to understand the long-standing pressures on this species and the limited conservation efforts made. Cultivation of A. granatensis is proposed as a crucial strategy to reduce pressure on wild populations and ensure the survival of this flagship important plant species.

Aim The African Guineo‐Congolian (GC) region is a global biodiversity hotspot with high species endemism, bioclimatic heterogeneity, complex landscape features, and multiple biogeographic barriers. Bioclimatic and geographic variables influence global patterns of species richness and endemism, but their relative importance varies across taxa and regions and is poorly understood for many faunas. Here, we test the hypothesis that turnover in endemic amphibians of the GC biodiversity hotspot is influenced mainly by the geographic distance between grid cells and secondarily by rainfall‐ and temperature‐related variables. Location West and Central Africa. Major Taxa Studied Amphibians. Methods We compiled species‐occurrence records via field sampling, online databases, and taxonomic literature. Our study used 1205 unique georeferenced records of 222 amphibian species endemic to the GC region. Patterns of species richness were mapped onto a grid with a spatial resolution of 0.5° × 0.5°. We estimated weighted endemism and tested whether endemism was higher than the expected species richness (randomization test). We quantified species turnover using generalized dissimilarity modelling to evaluate the processes underlying observed patterns of species richness in GC endemic amphibians. We explored bioregionalization using agglomerative hierarchical clustering based on the unweighted pair group method with arithmetic averages. Results We identified seven areas within the lower GC region – forests in Cameroon, Gabon, Southern Nigeria, Equatorial Guinea, Republic of Congo, Democratic Republic of Congo, and Cote d'Ivoire – as having high species richness of endemic amphibians. The randomization test returned four major areas of significant weighted endemism: Nigeria‐Cameroon mountains, forest regions of the Democratic Republic of Congo, Cote d'Ivoire, and Ghana. Our analysis revealed five bioregions for amphibian endemism, four of which were located within the lower Guineo‐Congolian forest. Species turnover was strongly related to the geographic distance between grid cells; contributing bioclimatic variables included precipitation of the warmest quarter, mean temperature of the wettest quarter, and mean diurnal temperature range. Main Conclusions Our results indicate that geographic distance between grid cells is the primary determinant of turnover in GC endemic amphibians, with secondary but significant effects of rainfall‐ and temperature‐related variables. Our study identifies key areas of endemic amphibian richness that could be prioritized for conservation actions.

Population monitoring is critical for informing the management and conservation of rare Hawaiian forest birds. In 2017, we used point-transect distance sampling methods to estimate population densities of birds on Haleakal a Volcano on east Maui island. We estimated the populations and ranges of three island-endemic Hawaiian honeycreepers, including the endangered ‘Ākohekohe (Palmeria dolei), the endangered Kiwikiu (Maui Parrotbill; Pseudonestor xanthophrys), and the Maui ‘Alauahio (Paroreomyza montana newtoni). We examined population trends back to 1980, and our 2017 density estimates were the lowest ever recorded for each species. Most concerning was the status of Kiwikiu, with a 71% decline in population since 2001 to a current population of 157 (95% CI 44–312) birds. The population of ‘Ākohekohe similarly decreased by 78% to a current population of 1768 (1193–2411) birds. For both species, population declines were due to declines in density and contraction of ranges from lower elevations. Both species are now restricted to ranges of less than 3000 ha. We surveyed ~ 91% of the range of Maui ‘Alauahio and estimated a population of 99,060 (88,502–106,954) birds, a 41% decrease since the highest estimate in 1992. Contraction of ranges to higher elevations is consistent with evidence that the impacts of avian malaria are being exacerbated by global warming trends. Our results indicate that the landscape control of either avian malaria transmission or its vector (Culex mosquitoes) will be a pre-requisite to preventing the extinction of endemic forest birds in Hawaii. El monitoreo poblacional es fundamental para informar sobre la gestión y la conservación de aves forestales raras aves de Hawai. En 2017, utilizamos métodos de muestreo de distancia de transectos puntuales para estimar las densidades de población de aves en el volcán Haleakalā en la isla este de Maui. Estimamos las poblaciones y áreas de distribución de tres trepadores de miel hawaianos endémicos de la isla, incluido la especie en peligro de extinción ‘Ākohekohe (Palmeria dolei), la especie en peligro de extición Kiwikiu (Pico de loro de Maui; Pseudonestor xanthophrys) y el Alauahio de Maui (Paroreomyza montana newtoni). Examinamos las tendencias de la población desde 1980, y nuestras estimaciones de densidad de 2017 fueron las más bajas jamás registradas para cada especie. Lo más preocupante fue el estado de Kiwikiu, con una disminución del 71% en la población desde 2001 a una población actual de 157 (IC del 95%: 44–312) aves. La población de ‘Ākohekohe disminuyó de manera similar en un 78% a una población actual de 1768 (1193–2411) aves. Para ambas especies, la disminución de la población se debió a la disminución de la densidad y la contracción de los rangos de las elevaciones más bajas. Ambas especies están ahora restringidas a áreas de distribución de menos de 3000 ha. Muestreamos ~ 91% del rango del Alauahio Maui y estimamos una población de 99,060 (88,502-106,954) aves, una disminución del 41% desde la estimación más alta en 1992. La contracción de rangos hacia elevaciones más altas son consistentes con evidencia de que los impactos de la malaria aviar se ve agravada por las tendencias del calentamiento global. Nuestros resultados indican que el control del paisaje de la transmisión de la malaria aviar o de su vector (mosquitos Culex) será un prerrequisito para prevenir la extinción de l.

Describing the natural history of endemic and endangered species is useful for developing effective conservation plans. Two important pieces of the natural history are the timing of reproduction and morphometrics. In this study, we estimated the reproductive season of Antioquia Brushfinch ( Atlapetes blancae ) based on a large database of observations and captures. We also provide the most extensive morphometric data base of males, females and subadult individuals for this species. Taking advantage of ecological modeling techniques, we estimated that the reproductive season of A. blancae most likely spans from February through late July with peak reproductive activity during early July. The reproductive activity is influenced by day length and precipitation. We also found that subadults are smaller than adults and females are smaller than males providing evidence for both, age and sexual size dimorphism. This study was the first attempt to provide important missing information about A. blancae that could help with the understanding of population viability.

Background Scrophularia oxyrhyncha (Scrophulariaceae), endemic to southwest Spain, is one of the species of the genus whose distribution across the Iberian Peninsula is most limited. In this study, we analyzed its reproductive system by evaluating its fruit and seed set after different treatments, floral phenology, reproductive success, and the predation level of two populations in the Extremadura region (Spain), inhabiting different substrates (quartzitic in the San Serván population, granitic in the Cornalvo population) between 2019 and 2022. Results Scrophularia oxyrhyncha presents protogyny, it is self-compatible but requires the presence of pollinators to produce offspring which, in quite a high percentage, would result from geitonogamous pollinations. The two populations did not differ significantly in their reproductive behaviour throughout the years studied, and both presented a spring synchronous pattern, somewhat longer in the San Serván population; this was probably due to the existence of two short second flowering periods caused by sheep predation suffered by individuals. The main threat to the populations was cattle grazing and, to a lesser extent, caterpillars. Conclusions Cattle grazing decreased reproductive success and altered the floral display in such a way that there was a flowering time-pollinator activity mismatch. The decline in reproductive success due to vertebrate predation depended on the time at which such predation occurred, with the most severe being late predation, that is, after peak flowering. Finally, we recommend that the pertinent authorities adopt measures to ensure the conservation and survival of the populations of this endemic species in Extremadura.

The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. Low genetic diversity and small effective population sizes (Ne) are expected for narrow endemic species (NES). Conservation biology studies centered in a single species show some limitations, but they are still useful considering the limited time and resources available for protection of species at risk of extinction. Here, we evaluated the genetic diversity, population structure, Ne, and minimum viable population (MVP) of I. cangae to provide information for effective conservation programs. Our analyses were based on 55 individuals collected from the Amendoim Lake and 35,638 neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and Ne in the order of thousands, contrasting the expected for NES. Negative FIS values were also found, suggesting that I. cangae is not under risk of inbreeding depression. Our findings imply that I. cangae contains enough genetic diversity to ensure evolutionary potential and that all individuals should be treated as one demographic unit. These results provide essential information to optimize ex situ conservation efforts and genetic diversity monitoring, which are currently applied to guide I. cangae conservation plans. The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. To provide information for effective conservation programs, we evaluated its genetic diversity and population structure using neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and effective population size in the order of thousands, contrasting to the expected for NES.

The loss of biodiversity in marine populations is one of the consequences of the increased events of extreme environmental conditions in the oceans, which can condition the persistence of populations to future scenarios of climate change. Therefore, it is extremely necessary to explore and monitor the genetic diversity of natural populations. In the Southeast Pacific Ocean (SEPO), specifically on the coast of Chile, the presence of the copepod Acartia tonsa has been indicated solely using morphological evidence, due to the absence of genetic information. In the present work, the genetic diversity, population structure and phylogenetic position within the genus Acartia , of populations identified morphologically as A. tonsa , was evaluated by amplification of the mitochondrial cytochrome c oxidase subunit I and nuclear marker 18 s. Our results showed that the populations identified as A. tonsa correspond to a new monophyletic group endemic to SEPO (GMYC = 1.00; PTP = 0.95). The populations showed moderate to high genetic diversity with an incipient structuring between populations and biogeographic zones. Our results suggest that despite the homogenizing effect of the Humboldt Current, isolation by distance and contrasting environmental conditions at different geographic scales have an important influence on the genetic diversity of zooplankton in the SEPO region.

Global climate change, dominated by climate warming, is seriously affecting the balance of global ecosystems, but the risk of species extinction is particularly high in low-altitude mountain areas. To clarify the response of the endemic and critically endangered species Ilex nanchuanensis to climate change, this study used the MaxEnt model to simulate and predict the potential habitat of I. nanchuanensis during the Last Interglacial, Last Glacial Maximum, the current period, and two future periods (the 2050 s and 2070 s). The results showed that the hottest monthly minimum temperature is the most important climatic factor affecting the geographical distribution of I. nanchuanensis. Furthermore, I. nanchuanensis will be at risk of population shrinkage and extinction in the future, with the center of mass moving further northwest as concentrations of greenhouse gases increase, especially in the 2070 s, when its geographical distribution shrinks the most under the RCP6 scenario. Therefore, to actively respond to the impacts of climate change, protected areas should be established around the geographical distribution centers of species, and core, buffer, and experimental areas should be scientifically and rationally delineated for the conservation and cultivation of germplasm resources.