Agriculture, Wildlife, and Conservation in the Galapagos Islands

Agriculture has profoundly transformed the humid highlands of inhabited islands in this UNESCO World Heritage Site. However, the agriculture and conservation sectors have historically had an antagonistic relationship. Therefore, this dissertation uses a mixed-methods approach to explore common interest points related to farmer livelihoods, invasive species control, and endemic species protection. These relationships are framed as part of a coupled human-natural system, where human and non-human agency constantly shape agroecosystems of the Galapagos (Chapter 2). For the first time, the land cover of Galapagos agroecosystems was mapped in high-resolution using categories relevant to both agriculture and conservation sectors (Chapter 3). Invasive plants cover the most considerable fraction of the agricultural areas (28.5%), followed by pastures (22.3%), native vegetation (18.6%), food crops (18.3), and mixed forest and pioneer plants (11.6%). Interviews and socioeconomic data were used to categorize land use and farming practices in the Galapagos along an agroecological spectrum (Chapter 4). There is a wide range of farming practices, but 44.1% of farms were categorized as conventional, 52% of farms were ranked as transition, and 28% were categorized as agroecological. The newly generated land cover and land use datasets were used to create habitat suitability maps for the emblematic giant tortoises (Chelonoidis spp., Chapter 5). The predicted suitable habitat for tortoises in Santa Cruz extends over 6839.9 ha. In the case of C. porteri, 29% of their predicted suitable habitat is within agricultural areas. In San Cristobal, C. chathamensis has a predicted suitable habitat of about 2581 ha, mainly in the northern regions. Still, interviews with key stakeholders of the food system suggest tortoises are migrating south and entering the agricultural areas. Farmers have complex and context-dependent relationships with invasive plants like Psidium guajava as well as with giant tortoises. Farmer experiences that reconcile agricultural activities with tortoise conservation as well as with P. guajava management were documented. I hope that these studies increase the rural sector's representation for regional policymaking and encourage collaboration between agriculture and conservation sectors.Doctor of Philosoph

Sharing land with giants: Habitat preferences of Galapagos tortoises on farms

One of the most pressing dilemmas of our time is determining how to satisfy the demands of a growing human population while still conserving biodiversity. Worldwide, land modification to accommodate human resource needs has caused significant declines in wildlife populations. To help minimize biodiversity loss, we must support wildlife on human-dominated land, such as farms and urban areas, but our knowledge of how to do so is lacking. Agriculture is a major driver of land modification; but also has the potential to play a role in conserving biodiversity. To support critically endangered ecosystem engineers that use farms, such as giant Galapagos tortoises, we need to understand the characteristics encouraging or hindering them. To quantify tortoise habitat preferences, we assessed the relationship between tortoise density, habitat structure, and land-use type, by recording tortoise density on farms on Santa Cruz Island, Galapagos, over two years. Tortoise density was lowest in abandoned farmland and highest in tourist areas and was most strongly positively correlated with abundant ground cover, short vegetation, and few shrubs. The habitat features favoured by tortoises could potentially be manipulated to help support tortoise conservation on farms. Measuring wildlife preferences in human-dominated areas is an important step towards balancing biodiversity conservation and human-enterprise

The interaction between giant tortoises and agriculture in the Galapagos Islands

Kyana Pike investigated the interaction between giant tortoises and agriculture on Santa Cruz, Galapagos. She found farmland remains an important habitat for tortoises and their abundance, behaviour, and movement are strongly influenced by land-use type, habitat structure and infrastructure. Findings are being used as evidence-based decision support for wildlife managers

Linking animal migration and ecosystem processes: Data-driven simulation of propagule dispersal by migratory herbivores

Animal migration is a key process underlying active subsidies and species dispersal over long distances, which affects the connectivity and functioning of ecosystems. Despite much research describing patterns of where animals migrate, we still lack a framework for quantifying and predicting how animal migration affects ecosystem processes. In this study, we aim to integrate animal movement behavior and ecosystem functioning by developing a predictive modeling framework that can inform ecosystem management and conservation.We propose a framework to model individual-level migration trajectories between populations' seasonal ranges as well as the resulting dispersal and fate of propagules carried by the migratory animals, which can be calibrated using empirical data at every step of the modeling process. As a case study, we applied our framework to model the spread of guava seeds, Psidium guajava, by a population of migratory Galapagos tortoises, Chelonoidis porteri, across Santa Cruz Island. Galapagos tortoises are large herbivores that transport seeds and nutrients across the island, while Guava is one of the most problematic invasive species in the Galapagos archipelago.Our model can predict the pattern of spread of guava seeds alongside tortoises' downslope migration range, and it identified areas most likely to see establishment success. Our results show that Galapagos tortoises' seed dispersal may particularly contribute to guava range expansion on Santa Cruz Island, due to both long gut retention time and tortoise's long-distance migration across vegetation zones. In particular, we predict that tortoises are dispersing a significant amount of guava seeds into the Galapagos National Park, which has important consequences for the native flora.The flexibility and modularity of our framework allow for the integration of multiple data sources. It also allows for a wide range of applications to investigate how migratory animals affect ecosystem processes, including propagule dispersal but also other processes such as nutrient transport across ecosystems. Our framework is also a valuable tool for predicting how animal-mediated propagule dispersal can be affected by environmental change. These different applications can have important conservation implications for the management of ecosystems that include migratory animals

Memorias del 3er Simposio de Investigación & Conservación en Galápagos GSC– DPNG

Memorias del 3er Simposio de Investigación & Conservación en Galápagos GSC– DPN

Scientific Research in Ecuador: A Bibliometric Analysis

Ecuador has shown a growth in its scientific production since 2011, representing 85% of the total historical production. These investigations are reflected in scientific publications, which address world interest topics and serve as a link for the university, business, and society. This work aims to analyze the scientific production generated by Ecuador in the period of 1920–2020 using bibliometric methods to evaluate its intellectual structure and performance. The methodology applied in this study includes: (i) terms definition and search criteria; (ii) database selection, initial search, and document compilation; (iii) data extraction and software selection; and finally, (iv) analysis of results. The results show that scientific production has been consolidated in 30,205 documents, developed in 27 subject areas, in 13 languages under the contribution of 84 countries. This intellectual structure is in harmony with the global context when presenting research topics related to “Biology and regional climate change”, “Higher education and its various approaches”, “Technology and Computer Science”, “Medicine”, “Energy, food and water”, and ”Development and applications on the Web”. Topics framed in the Sustainable Development Goals (SDGs), sustainability, climate change, and others. This study contributes to the academic community, considering current re-search issues and global concerns, the collaboration between universities and countries that allow establishing future collaboration links

Enhancing performance of multi-temporal tropical river landform classification through downscaling approaches

Data availability: Data are available from: https://doi.org/10.5525/gla.researchdata.1355.Supplementary material: Supplemental data for this article can be accessed online at https://doi.org/10.1080/01431161.2022.2139164 .Copyright 2022 The Author(s). Multi-temporal remote sensing imagery has the potential to classify river landforms to reconstruct the evolutionary trajectory of river morphologies. Whilst open-access archives of high spatial resolution imagery are increasingly available from satellite sensors, such as Sentinel-2, there remains a fundamental challenge of maximising the utility of information in each band whilst maintaining a sufficiently fine resolution to identify landforms. Although image fusion and downscaling methods on Sentinel-2 imagery have been investigated for many years, there is a need to assess their performance for multi-temporal object-based river landform classification. This investigation first compared three downscaling methods: area to point regression kriging (ATPRK), super-resolution based on Sen2Res, and nearest neighbour resampling. We assessed performance of the three downscaling methods by accuracy, precision, recall and F1-score. ATPRK was the optimal downscaling approach, achieving an overall accuracy of 0.861. We successively engaged a set of experiments to determine an optimal training model, exploring single and multi-date scenarios. We find that not only does remote sensing imagery with better quality improve river landform classification performance, but multi-date datasets for establishing machine learning models should be considered for contributing higher classification accuracy. This paper presents a workflow for automated river landform recognition that could be applied to other tropical rivers with similar hydro-geomorphological characteristics. Key policy highlights . Choice of downscaling approach influences the performance of river landform classification from satellite imagery and should be considered in river and flood management. . An efficient and straightforward operating workflow was developed for automated river landform classification with high accuracy that supports an improved understanding of the use of machine learning approaches in river landform recognition. . Freely available and easy-to-access remote sensing datasets can help extend the operating workflow to difficult-to-access or remote regions and allow for complete regional and/or national coverage.China Scholarship Council [201908060049] and University of Glasgow [201908060049]

The influence of hybridization on range dynamics

Hybridization can have a significant influence on the evolutionary trajectories of both plant and animal lineages, resulting in a variety of outcomes including – but not limited to – range expansion, stabilization, and decay. When early generation hybrids have high fitness, or when adaptive genetic variation is transferred between the genetic backgrounds of hybridizing taxa via so-called adaptive introgression, hybridization can facilitate the colonization of novel environments, resulting in range expansion. On the other hand, when hybrids have low fitness, or when other negative sexual interactions occur, frequent heterospecific mating can result in a reduction in parental fitness via wasting reproductive effort. One potential result of this evolutionarily unstable scenario is the evolution of reproductive characters to avoid heterospecific mating (ie. reproductive character displacement and reinforcement), which may stabilize range boundaries. Another potential result is that one of the two lineages is excluded from sympatry before reinforcement can evolve, leading to range decay. Although much attention has been paid to reinforcement due to the important implications it has for the process of speciation, relatively less is known about the factors that influence when hybridization results in range expansion and decay.The body of work presented here seeks to help fill this knowledge gap by exploring a number of ecological and evolutionary genetic factors that influence when and how hybridization leads to range expansion and decay. I focus predominantly on island systems because islands: i) offer unique eco-evolutionary contexts that may encourage heterospecific mating in secondary contact, ii) host an alarming number of biological invasions where hybridization may have influenced range dynamics and, consequently, iii) offer systems where the influence of hybridization on range dynamics may have immediate ramifications for the conservation of native species. In my first chapter, I present an ecological and evolutionary framework for understanding the causes and consequences of hybridization on islands – with particular emphasis on the influence of genetic divergence on outcomes of hybridization. In my second chapter, I use a population genetic modeling approach to generate predictions about how genetic architecture influences the contribution of hybridization to range expansion. In my third chapter, I explore the potential role of hybridization in facilitating the range expansion of invasive Psidium guajava in the Galápagos Islands. In my fourth and final chapter, I investigate whether reproductive interference with invasive guava may be contributing to the ongoing range decay of guayabillo in the Galápagos.Doctor of Philosoph

Proceedings of the 5th International Symposium on Biological Control of Arthropods

This proceedings contains papers dealing with issues affecting biological control, particularly pertaining to the use of parasitoids and predators as biological control agents. This includes all approaches to biological control: conservation, augmentation, and importation of natural enemy species for the control of arthropod targets, as well as other transversal issues related to its implementation. It has 14 sessions addressing the most relevant and current topics in the field of biological control of arthropods: (i) Accidental introductions of biocontrol agens: positive and negative aspects; (ii) The importance of pre and post release genetics in biological control; (iii) How well do we understand non-target impacts in arthropod biological control; (iv) Regulation and access and benefit sharing policies relevant for classical biological control approaches; (v) The role of native and alien natural enemy diversity in biological control; (vi) Frontiers in forest insect control; (vii) Biocontrol marketplace I; (viii) Weed and arthropod biological control: mutual benefits and challenges; (ix) Maximizing opportunities for biological control in Asia's rapidly changing agro-environments; (x) Biological control based integrated pest management: does it work?; (xi) Exploring the compatibility of arthropod biological control and pesticides: models and data; (xii) Successes and uptake of arthropod biological control in developing countries; (xiii) Socio-economic impacts of biological control; (xiv) Biocontrol marketplace II