scholarly journals Population structure, stand-level dieback and recovery of Scalesia pedunculata forest in the Galápagos Islands

1988 ◽  
Vol 3 (3) ◽  
pp. 333-339 ◽  
Author(s):  
Syuzo Itow ◽  
Dieter Mueller-Dombois
1992 ◽  
Vol 49 (1) ◽  
pp. 78-84 ◽  
Author(s):  
Hal Whitehead ◽  
Susan Waters ◽  
Thomas Lyrholm

The structure of the population of female and immature sperm whales (Physeter macrocephalus) in the region of the Galápagos Islands was studied using individual photographic identifications of 1285 animals collected between 1985 and 1989. Population parameters were estimated using a maximum-likelihood mark–recapture estimate permitting emigration from the study area in which identifications are collected and then reimmigration back into it. Because permanent associations among whales violated assumptions of independence, confidence intervals for the estimates were constructed using Monte-Carlo population simulation. The analysis suggested that there is a population of very approximately 200 whales in the study area around the islands at any time. These were part of a larger population numbering between 2600 and 5300 individuals (95% confidence interval). An average of 39–94% (95% confidence interval) of the whales left the study area in any month, with a similar number immigrating.


2017 ◽  
Vol 8 ◽  
Author(s):  
Yveline Pailles ◽  
Shwen Ho ◽  
Inês S. Pires ◽  
Mark Tester ◽  
Sónia Negrão ◽  
...  

2020 ◽  
Author(s):  
Diego Urquia ◽  
Gabriela Pozo ◽  
Bernardo Gutierrez ◽  
Jennifer K. Rowntree ◽  
Maria de Lourdes Torres

ABSTRACTOceanic archipelagos are known to host a variety of endemic plant species. The genetic diversity and structure of these species is an important indicator of their evolutionary history and can inform appropriate conservation strategies that mitigate the risks to which they’re exposed, including invasive species and environmental disturbances. A comprehensive consideration of the role of their natural history, as well as the landscape features and the geological history of the islands themselves is required to adequately understand any emerging patterns. Such is the case for the guayabillo (Psidium galapageium), an understudied endemic plant from the Galapagos Islands with important ecological and economic roles. In this study we designed and evaluated 13 informative SSR markers and used them to investigate the genetic diversity, population structure and connectivity of the guayabillo populations from San Cristobal, Isabela and Santa Cruz islands. A total of 208 guayabillo individuals were analyzed, revealing a strong population structure between islands and two distinct genetic lineages for the Santa Cruz population. Overall, the guayabillo genetic diversity is relatively high, an unusual pattern for an insular endemic species which is possibly explained by its polyploidy and the geographical features of the islands. These include their broad altitudinal ranges and habitat heterogeneity. For populations displaying a lower genetic diversity such as San Cristobal, the history of human disturbance could be an important factor explaining these observations. Some similarities between individuals in Santa Cruz and the San Cristobal population could be explained by population differentiation or distinct natural histories of separate lineages. Our findings highlight the complex population dynamics that shape the genetic diversity of species like the guayabillo and emphasize the need to explore the currently unresolved questions about this Galapagos endemic plant.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Daniel Escobar-Camacho ◽  
Paulina Rosero ◽  
Mauricio Castrejón ◽  
Carlos F. Mena ◽  
Francisco Cuesta

AbstractThe unique marine and terrestrial ecosystems of the Galapagos Islands are highly vulnerable to human-based drivers of change, including the introduction of invasive species, unsustainable tourism, illegal fishing, overexploitation of ecosystem services, and climate change. These drivers can interact with climate-based drivers such as El Niño-Southern Oscillation (ENSO) at multiple temporal and spatial scales, exacerbating their negative impacts on already fragile ecosystems and the socioeconomic system of the Archipelago. In this review, we performed a literature review based on published literature from 1945 to 2020 and local and global climate databases to analyze drivers of change in the Galapagos. We developed and applied a spatial impact assessment model to identify high-ecological value areas with high sensitivity and exposure scores to environmental change drivers. We identified 13 priority HEVA that encompass ca. 23% (14,715 km2) of the Galapagos Archipelago, distributed in nearly 3% of the Galapagos Marine Reserve and 20% Galapagos National Park. Current and future impacts are likely to concentrate on the inhabited islands’ highlands, whereas marine impacts concentrate along most of the Galapagos Islands’ shorelines. These results are important for guiding the design and implementation of adaptation measures aimed at increasing ecosystem resilience and human adaptive capacity in the face of global environmental change. Overall, these results will be valuable in their application for preserving Galapagos biota, securing the provision of vital ecosystem services for resident human populations, and sustaining the nature-based tourism industry.


2021 ◽  
pp. 100180
Author(s):  
William F. Vásquez ◽  
Nejem Raheem ◽  
Diego Quiroga ◽  
Valeria Ochoa-Herrera

2011 ◽  
Vol 65 (4) ◽  
pp. 507-513 ◽  
Author(s):  
Mark S. Hoddle ◽  
Laurence A. Mound

Author(s):  
Polpass Arul Jose ◽  
Michael Ben‐Yosef ◽  
Paola Lahuatte ◽  
Charlotte E. Causton ◽  
George E. Heimpel ◽  
...  

Author(s):  
A. Cano ◽  
Paul Arévalo ◽  
F. Jurado

This research compared different sizing methods to improve the current autonomous hybrid system in the Galapagos Islands in 2031, analyzing the loss of power supply probability (LPSP).


Sign in / Sign up

Export Citation Format

Share Document