Nicole EstebanSwansea University | SWAN · Department of Biosciences
Nicole Esteban
PhD
About
55
Publications
24,735
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1,344
Citations
Citations since 2017
Introduction
Additional affiliations
December 2010 - present
April 2003 - July 2010
St Eustatius National Parks
Position
- Parks Manager
Publications
Publications (55)
There are major concerns about the ecological impact of extreme weather events. In the oceans, marine heatwaves (MHWs) are an increasing threat causing, for example, recent devastation to coral reefs around the world. We show that these impacts extend to adjacent terrestrial systems and could negatively affect the breeding of endangered species. We...
• Satellite tracking of animals is very widespread across a range of marine, freshwater, and terrestrial taxa. Despite the high cost of tags and the advantages of long deployments, the reasons why tracking data from tags stop being received are rarely considered, but possibilities include shedding of the tag, damage to the tag (e.g., the aerial), b...
In 1873, Charles Darwin marveled at the ability of sea turtles to find isolated island breeding sites [1], but the details of how sea turtles and other taxa navigate during these migrations remains an open question [2]. Exploring this question using free-living individuals is difficult because, despite thousands of sea turtles being satellite track...
Increasing incubation temperatures may threaten the viability of sea turtle populations. We explored opportunities for decreasing incubation temperatures at a Caribbean rookery with extreme female-biased hatchling production. To investigate the effect of artificial shading, temperatures were measured under simple materials (white sheet, white sand,...
Estimating the absolute number of individuals in populations and their fecundity is central to understanding the ecosystem role of species and their population dynamics as well as allowing informed conservation management for endangered species. Estimates of abundance and fecundity are often difficult to obtain for rare or cryptic species. Yet, in...
Dive studies across mammals, birds, reptiles and fish often focus on deep dives, and shallow water diving has tended to be overlooked. For air-breathers, foraging in shallow water poses challenges since the lungs generate buoyancy, and shallow divers must trade off the extent of inhalation against the negative buoyancy needed to avoid floating to t...
Estimating population abundance is central to many ecological studies and important in conservation planning. Yet the elusive nature of many species makes estimating their abundance challenging. Abundance estimates of sea turtles , marine birds, and seals are usually made when breeding adults are ashore, while life stages spent at sea, including as...
To maximize the opportunities of seagrass as a nature-based solution requires restoration to occur on a large scale. New methods and knowledge are required that can solve ecological bottlenecks, improving its reliability and effectiveness. Although there is increasing interest in the use of seeds for seagrass restoration there exists a limited unde...
Around the world, declines in the mean size of nesting sea turtles have been reported with concerns of a concomitant decrease in the reproductive output of populations. Here, we explore this possibility using long-term observations of green turtles (Chelonia mydas) at Aldabra Atoll, Seychelles. Based on > 4500 individual measurements over 21 years...
Seagrass meadows commonly reside in shallow sheltered coastal environments which are typically safe havens for mooring boats. There is evidence from around the globe that the use of common swinging chain moorings leads to halos of bare sediment in otherwise productive seagrass. These halos reduce animal abundance and diversity and lead to a loss of...
We report Anthropogenic Marine Debris (AMD) in Chagos Archipelago in the Indian Ocean, globally amongst the most isolated island groups. AMD on 14 island beaches in five atolls were surveyed in 2019 using two techniques: Marine Debris Tracker (MDT) along littoral vegetation and photoquadrats in open beach. Over 60 % of AMD in both beach zones was c...
How animals navigate across the ocean to isolated targets remains perplexing greater than 150 years since this question was considered by Charles Darwin. To help solve this long-standing enigma, we considered the likely resolution of any map sense used in migration, based on the navigational performance across different scales (tens to thousands of...
Aim
Understanding the spatial ecology of animal movements is a critical element in conserving long‐lived, highly mobile marine species. Analyzing networks developed from movements of six sea turtle species reveals marine connectivity and can help prioritize conservation efforts.
Location
Global.
Methods
We collated telemetry data from 1235 indivi...
Coastal ecosystems provide vital ecosystem functions and services, but have been rapidly degrading due to human impacts. Restoration is increasingly considered key to reversing these losses, but is often unsuccessful. Recent work on seagrasses and salt marsh cordgrasses highlights that restoration yields can be greatly enhanced by temporarily mimic...
Supplemental Information for "Reconstructing past thermal conditions in beach microclimates".
Reconstruction of past conditions provides important information on how ecosystems have been impacted by climate change, but generally for microhabitats worldwide there are no long-term empirical measurements. In these cases, there has been protracted debate about how various large-scale environmental proxies can best be used to reconstruct local t...
Space use estimates can inform conservation management but relaying high‐accuracy locations is often not straightforward. We used Fastloc‐GPS Argos satellite tags with the innovation of additional data relay via a ground station (termed a “Mote”) to record high volumes (typically > 20 locations per individual per day) of high accuracy tracking data...
The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundr...
Supplemental Information for " Impacts of marine heatwaves for sea turtle incubation conditions".
Supplemental Information for "Why do Argos satellite tags stop relaying data?".
To better understand dietary requirements, trophic shifts, and trophic interactions of the threatened green turtle (Chelonia mydas), we conducted a comprehensive global review and literature tabulation (177 studies) reporting diets of individuals > 25 cm carapace length. We analysed those studies involving natural sites and healthy animals that rep...
Supplemental Information for "A global review of green turtle diet: sea surface temperature as a potential driver of omnivory levels".
Given the recent trend towards establishing very large marine protected areas (MPAs) and the high potential of these to contribute to global conservation targets, we review outcomes of the last decade of marine conservation research in the British Indian Ocean Territory (BIOT), one of the largest MPAs in the world. The BIOT MPA consists of the atol...
Restoration is becoming a vital tool to counteract coastal ecosystem degradation. Modifying transplant designs of habitat-forming organisms from dispersed to clumped can amplify coastal restoration yields as it generates self-facilitation from emergent traits, i.e. traits not expressed by individuals or small clones, but that emerge in clumped indi...
1. Estimates of space use derived from animal tracking studies are often biased by where animals are tagged, with areas distant to the tagging site, in both space and time, being under‐represented. 2. We develop an approach to overcome this tagging bias by quantifying the likely movements of animals after tags have failed. 3. We illustrate the appr...
Patterns of animal movement associated with foraging lie at the heart of many ecological studies and often animals face decisions of staying in an environment they know, versus relocating to new sites. The lack of knowledge of new foraging sites means there is risk associated with a decision to relocate (e.g. poor foraging) as well as a potential b...
Global marine turtle population assessments highlight the importance of the south-west Indian Ocean region, despite data gaps for the Chagos Archipelago. The archipelago hosts nesting hawksbill Eretmochelys imbricata and green turtles Chelonia mydas, both heavily exploited for 2 centuries until protection in 1968–1970. We assessed available nesting...
Green turtles (Chelonia mydas) are key herbivores of tropical and subtropical neritic habitats and play a major role in structuring seagrass meadows. We present the first detailed assessment of green turtle diet in the Western Indian Ocean using the gut contents of salvaged animals from three atolls in the Republic of Seychelles separated from each...
We review how unmanned aerial vehicles (UAVs), often referred to as drones, are being deployed to study the abundance and behaviour of sea turtles, identifying some of the commonalities and differences with studies on other marine vertebrates, including marine mammals and fish. UAV studies of all three groups primarily focus on obtaining estimates...
Sea turtles are vertebrates with temperature-dependent sex determination. Rising temperatures due to climate change cause female-biased sex ratios. We have assessed the influence of nest depth and shading conditions on nest temperatures and hatchling fitness of the leatherback sea turtle (Dermochelys coriacea). We relocated 48 leatherback clutches...
Seagrass meadows are an important wetland habitat that have been degraded globally but have an important carbon storage role. In order to expand the restoration of these productive and biodiverse habitats methods are required that can be used for large scale habitat creation across a range of environmental conditions. The spreading of seagrass seed...
There have been efforts around the globe to track individuals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, w...
Our understanding of global seagrass ecosystems comes largely from regions characterized by human impacts with limited data from habitats defined as notionally pristine. Seagrass assessments also largely focus on shallow-water coastal habitats with comparatively few studies on offshore deep-water seagrasses. We satellite tracked green turtles (Chel...
Seagrasses are hugely valuable to human life, but the global extent of seagrass meadows remains unclear. As evidence of their value, a United Nations program exists (http://data.unep-wcmc.org/datasets/7) to try and assess their distribution and there has been a call from 122 scientists across 28 countries for more work to manage, protect and monito...
The advent of Fastloc-GPS is helping to transform marine animal tracking by allowing the collection of high-quality location data for species that surface only briefly. We show how the improved location accuracy of Fastloc-GPS compared to Argos tracking is expected to lead to far more accurate home range estimates, particularly for animals moving o...
Determining the time of day that animals initiate and end migration, as well as variation in diel movement patterns during migration, provides insights into the types of strategy used to maximise energy efficiency and ensure successful completion of migration. However, obtaining this level of detail has been difficult for long-distance migratory ma...
An animal’s home range is driven by a range of factors including top-down (predation risk) and bottom-up (habitat quality) processes, which often vary in both space and time. We assessed the role of these processes in driving spatiotemporal patterns in the home range of the green turtle (Chelonia mydas), an important marine megaherbivore. We satell...
Sand temperatures at nest depths and implications for hatchling sex ratios of hawksbill turtles (Eretmochelys imbricata) and green turtles (Chelonia mydas) nesting in the Chagos Archipelago, Indian Ocean are reported and compared to similar measurements at rookeries in the Atlantic and Caribbean. During 2012–2014, temperature loggers were buried at...
Satellite transmitters were deployed on three green turtles, Chelonia mydas, and two hawksbill turtles, Eretmochelys imbricata, nesting in the Lesser Antilles islands, Caribbean, between 2005 and 2007 to obtain preliminary information about the inter-nesting, migratory and foraging habitats in the region. Despite the extremely small dataset, both y...
Large marine protected areas (MPAs), each hundreds of thousands of square kilometers, have been set up by governments around the world over the last decade as part of efforts to reduce ocean biodiversity declines, yet their efficacy is hotly debated. The Chagos Archipelago MPA (640,000 km 2) (Indian Ocean) lies at the heart of this debate. We condu...
At least 33 native species of marine mammals have been documented from the Wider Caribbean Region (WCR). For many of these species, the waters of the region serve as primary habitat for critical activities that include feeding, mating and calving. However, relatively little remains known about their biology, life history, distribution and behavior,...
Until the early 1990s, information on sea turtle nesting in the Netherlands Antilles amounted to little more than a few anecdotal accounts and sea turtle nesting was considered nothing more than a rare or accidental occurrence. However, several recent studies have found significant levels of sea turtle nesting activity and have served as an importa...
Until the early 1990s, information on sea turtle nesting in the Netherlands Antilles amounted to little more than anecdotal accounts and sea turtle nesting was considered to be nothing more than a rare accidental occurrence. However, several recent studies have found unprecedented levels of sea turtle nesting activity and have served as an importan...
Projects
Project (1)
The goal of this project is to drive growth in the Welsh blue economy by supporting the developing commercial marine renewable sector in Wales. It will do this through co-production of the knowledge required to reduce the risk to industry based on first class research carried out at the Universities of Bangor and Swansea. New data and information will be acquired through linked coastal observatories and advanced numerical models and disseminated via an environmental informatics infrastructure - the Environmental Knowledge Systems Hub (ENVOKH).
http://www.seacams.ac.uk/
