Natacha Aguilar de Soto

Universidad de La Laguna | ULL · Soon joining Spanish Oceanographic Institution (CSIC)

El proyecto Interespecies ha realizado una caracterización del escenario de interacciones entre la pesca artesanal y cetáceos, elasmobranquios, tortugas y aves a nivel archipelágico. Se han detectado interacciones de colaboración, depredación/rotura y captura accidental de cetáceos, elasmobranquios, tortugas y aves. La frecuencia e intensidad de la...

Interactions between cetaceans and fisheries are a worldwide problem including in the Canary Islands (Spain). Here, the small-scale fishing fleet plays a role in maintaining the food security of the archipelago as well as socioeconomic and cultural values. The Canary Islands waters contain 30 species of cetaceans protected under Spanish (Law 42/200...

Sperm whales are known for producing powerful clicks that allow them to echolocate mesopelagic prey at long ranges in the darkness of the deep ocean, during long and deep dives. However, sperm whales sometimes switch from pelagic to benthic or benthopelagic foraging at or near the highly reflective seafloor, raising the question of how the most pow...

Deep diving toothed whales evolved to predate on the biggest biomass on Earth in the Deep-Scattering-Layer (DSL) and Benthic-Boundary-Layer (BBL). The behavioural ecology of these more than 20 species of air-breathing predators might include interspecific competition leading to spatial segregation or coexistence. Here we used DTAGs to investigate...

Cetaceans are the top predators of their ecosystems, however, little is known about deep-diving cetaceans, since they feed at depths where light does not reach. Therefore, the great ally in the study of deep-diving whales is sound and sperm whales produce the most powerful sounds in the animal kingdom for long-range echolocation during long and dee...

Recent fieldwork strategies and early results on tagged Short-Finned Pilot Whales during 2021 and 2022 in South Tenerife, Canary Islands, Spain. Published in the SATURN's Project Newsletter. https://www.saturnh2020.eu/post/newsletter-issue-no-2

To understand the effects of anthropogenic disturbance on the nutritional health of animals, it is important to measure and understand the morphometrics, allometrics, and body condition of the species. We examined the body shape, allometric relationships, and body condition of short-finned pilot whales (Globicephala macrorhynchus) in three location...

This project, integrated within the SATURN consortium and led by Dr. Natacha Aguilar de Soto from the University of La Laguna (ULL), aims to identify the sounds that are most harmful to cetaceans and how they impact the behavior of these animals. Passive acoustic monitoring (PAM) methods and maritime traffic data have been used in collaboration wit...

UP TO 300 WORDS in ONE PAGE): Sperm whales produce the most powerful sounds in the animal kingdom for long-range echolocation of mesopelagic prey during long and deep dives. Occasionally, sperm whales switch from pelagic to benthic-benthopelagic foraging at or near to the highly reflective seafloor, raising the question of how the most powerful bio...

The steep bathymetry of the volcanic archipelago of the Canary Islands favors finding an exceptional deep-water fauna near the coast. The Deep Scattering Layer (DSL) is considered the largest biomass of the planet but it is still largely unknown. Here we contribute quantification methods. The DSL occurs in the mesopelagic domain (200-1000 m) and pe...

Large predators typically feed on proportionally sized prey but the world's largest animals, baleen whales, bulk feed on plankton and small fishes. While most baleen whales migrate to feed on polar aggregations of nutritious zooplankton prey, Bryde's whales (Balaenoptera edeni brydei and B. e. edeni) inhabit less productive warm‐temperate waters wi...

The number and size of whale-watching and swim-with-cetacean vessels are increasing worldwide, but the noise impact on targeted species depends on vessel source characteristics, which remain largely unquantified. Here, we report the acoustic characteristics from 13 whale-watching vessels from Australia and Canary Islands. Acoustic recorders were de...

Abstract available in English, Spanish and Portuguese. The deep sea has been described as the last major ecological frontier, as much of its biodiversity is yet to be discovered and described. Beaked whales (ziphiids) are among the most visible inhabitants of the deep sea, due to their large size and worldwide distribution, and their taxonomic div...

Acceleration‐based proxies for activity and energy expenditure are widely used in bio‐logging studies of animal movement and locomotion to explore biomechanical strategies, energetic costs of behaviour, habitat use and the impact of anthropogenic disturbance. The foremost such proxy is overall dynamic body acceleration (ODBA) along with variants Ve...

Visual predators rely on fast-acting optokinetic responses to track and capture agile prey. Most toothed whales, however, rely on echolocation for hunting and have converged on biosonar clicking rates reaching 500/s during prey pursuits. If echoes are processed on a click-by-click basis, as assumed, neural responses 100× faster than those in vision...

Wide-ranging connectivity patterns of common bottlenose dolphins (Tursiops trunca-tus) are generally poorly known worldwide and more so within the oceanic archipelagos of Macaronesia in the North East (NE) Atlantic. This study aimed to identify long-range movements between the archipelagos of Macaronesia that lie between 500 and 1,500 km apart, and...

Short-finned pilot whales (Globicephala macrorhynchus) are large, deep-diving predators with diverse foraging strategies, but little is known about their echolocation. To quantify the source properties of short-finned pilot whale clicks, we made 15 deployments off the coast of Tenerife of a deep-water hydrophone array consisting of seven autonomous...

Echolocating animals that forage in social groups can potentially benefit from eavesdropping on other group members, cooperative foraging or social defence, but may also face problems of acoustic interference and intra-group competition for prey. Here, we investigate these potential trade-offs of sociality for extreme deep-diving Blainville′s and C...

Fear of predation can induce profound changes in the behaviour and physiology of prey species even if predator encounters are infrequent. For echolocating toothed whales, the use of sound to forage exposes them to detection by eavesdropping predators, but while some species exploit social defences or produce cryptic acoustic signals, deep-diving be...

For vocal animals with distinctive calls, passive acoustic monitoring can be used to infer presence, distribution, and abundance provided that the calls and calling behaviour are known. Key to enabling quantitative acoustic surveys are calibrated recordings of identified species from which the source parameters of the sounds can be estimated. Obtai...

Deep-diving whales must meet their energetic requirements by foraging efficiently in time-limited dives. Pilot whales are active hunters that sprint to catch few prey items while beaked whales target more low-caloric prey. Within depth-stratified pelagic habitats, the mesopelagic deep scattering layer constitutes the highest biomass concentration i...

Poster MSc Thesis in World Marine Mammal Conference 2019

Sperm whales (Physeter macrocephalus) produce powerful clicks that allow them to echolocate prey at long ranges in the darkness of the deep ocean. They use information gleaned by echolocation to choose dynamically the foraging habitat targeted in each dive. At high latitudes they exploit epi-, meso-, and benthopelagic prey with highly variable divi...

Echolocating toothed whales produce powerful clicks pneumatically to detect prey in the deep sea where this long-range sensory channel makes them formidable top predators. However, air supplies for sound production compress with depth following Boyle’s law suggesting that deep-diving whales must use very small air volumes per echolocation click to...

Mass stranding events (MSEs) of beaked whales (BWs) were extremely rare prior to the 1960s but increased markedly after the development of naval mid-frequency active sonar (MFAS). The temporal and spatial associations between atypical BW MSEs and naval exercises were first observed in the Canary Islands, Spain, in the mid-1980s. Further research on...

Aim The knowledge of a species biogeographical patterns greatly enhances our understanding of geographical ecology, which can improve identifying key conservation needs. Yet, this knowledge is still scarce for many marine top predators. Here, we aim to analyse movement patterns and spatial structuring of a large predator, the short‐finned pilot wha...

Until the 1990s, beaked whales were one of the least understood groups of large mammals. Information on northern bottlenose whales (Hyperoodon ampullatus) and Baird’s beaked whales (Berardius bairdii) was available from data collected during whaling, however, little information existed on the smaller species other than occasional data gleaned from...

The distribution of non-commercial large cephalopods is still largely unknown in spite of their important ecological role as top-predators in the oceans. Here we compile a large dataset of opportunistic findings of more than fifty giant/large cephalopods in the Canary Islands showing that the archipelago holds one of the highest rates of occurrence...

Many animals require intervals of rest or sleep in which their vigilance level is reduced. For marine fauna, including large baleen whales, resting potentially increases the risk of predation and vessel-strike. However, there is scarce information about how, and how often, whales rest which makes it difficult to assess the severity of this risk. He...

This work investigates whether a submarine volcanic eruption off El Hierro (Canary Islands) in October 2011 influenced the metal contents of two deep water cephalopod species: Abraliopsis morisii and Pyroteuthis margaritifera. This was assessed by comparing metal contents in specimens collected off the island of El Hierro and in the neighbouring is...

El objetivo principal del proyecto “Physico-chemical, biological and geological study of an underwater volcano in a degassing stage: island of El Hierro”, (VULCANO-II, CTM2014-51837-R) es estudiar, desde un punto de vista totalmente multidisciplinar, la fase de desgasificación activa del único volcán submarino monitoreado desde su nacimiento en agu...

Se estudiaron 180 muestras de dos especies de cefalópodos (Abraliopsis morisii y Pyroteuthis maragaritifera) de las islas de El Hierro, La Palma y Tenerife pescados en la campaña oceanográfica CETOBAPH. De las muestras se analizaron 20 metales pesados y se elaboró un estudio estadístico para comprobar si habían diferencias de concentraciones de met...

Blainville’s beaked whales (Mesoplodon densirostris) perform long deep foraging dives in which they use echolocation to hunt individual prey. Although social groups of Blainville's synchronize their dives, it is unknown if group size may affect their echolocation behaviour and specifically their vocal production, as has been proposed for bottlenose...

Passive acoustic monitoring has become an increasingly prevalent tool for estimating density of marine mammals, such as beaked whales, which vocalize often but are difficult to survey visually. Counts of acoustic cues (e.g., vocalizations), when corrected for detection probability, can be translated into animal density estimates by applying an indi...

The True’s beaked whale (Mesoplodon mirus, True 1913) is a poorly known member of the Ziphiidae family. Its distribution in the northern hemisphere is thought to be restricted to the temperate or warm temperate waters of the North Atlantic, while a few stranding records from the southern hemisphere suggest a wider and antitropical distribution, ext...

Gervais’ beaked whales in a group of four whales breaching repetitively in the Canary Islands, recorded by Roland Gockel (MEER)

Underwater video of True’ beaked whales recorded off the Azores by R Edler within the Master Mint program (report 8 Table 1)

The development of guidelines for mitigating noise impacts on marine fauna requires data about the biological relevance of noise effects and about the practicality of mitigation options. Recent expansion of scientific knowledge has shown that noise effects vary among animals with different behavioral ecophysiology. Beaked whales exemplify that some...

The Araguaian boto (Inia araguaiaensis), a newly described species of river dolphin, is also one of the most threatened cetaceans as it inhabits the most modified riverine system in the Amazon. To enable passive acoustic surveys of this species, we conducted a pilot study of a population associated with the municipal market of Mocajuba, Pará State,...

Los zifios presentan comportamientos de buceo y acústico que los distinguen de otros odontocetos, destacando su característico silencio cerca de superficie, a pesar de la cohesión de los grupos observados en emersión. Para comprobar si esta cohesión se traduce en coordinación en los perfiles de inmersión y sincronía de la actividad acústica durante...

Toothed whales use a pneumatic sound generator to produce echolocation and communication sounds. Increasing hydrostatic pressure at depth influences the amplitude and duration of calls but not of echolocation clicks. Here we test the hypothesis that information transfer at depth might be facilitated by click-based communication signals. Wild short-...

The sperm whale carries a hypertrophied nose that generates powerful clicks for long-range echolocation. However, it remains a conundrum how this bizarrely shaped apex predator catches its prey. Several hypotheses have been advanced to propose both active and passive means to acquire prey, including acoustic debilitation of prey with very powerful...

Restriction site-associated DNA (RAD) sequencing has become a popular approach to genotyping non-model organisms for ecological and evolutionary studies. However, there is difficulty in predicting how many variable loci will be recovered for a given protocol, combination of restriction enzymes and/or size selection criteria. Here we undertake a pil...

Studies of locomotion kinematics require high-resolution information about body movements and the specific acceleration (SA) that these generate. On-animal accelerometers measure both orientation and SA but an additional orientation sensor is needed to accurately separate these. Although gyroscopes can perform this function, their power consumption...

Sperm whales are present in the Canary Islands year-round, suggesting that the archipelago is an important area for this species in the North Atlantic. However, the area experiences one of the highest reported rates of sperm whale ship-strike in the world. Here we investigate if the number of sperm whales found in the archipelago can sustain the cu...

Systematic data collection of cetacean and seabird distribution in offshore waters is challenging due to the high costs of performing oceanic surveys. Opportunistic platforms such as ferries have proven to be effective in gathering consistent data in local areas and in large offshore routes. Data are used to study the spatial and temporal distribut...

Systematic data collection of cetacean and seabird distribution in offshore waters is challenging due to the high costs of performing oceanic surveys. Opportunistic platforms such as ferries have proven to be effective in gathering consistent data in local areas and in large offshore routes. Data are used to study the spatial and temporal distribut...

Systematic data collection of cetacean and seabird distribution in offshore waters is challenging due to the high costs of performing oceanic surveys. Opportunistic platforms such as ferries have proven to be effective in gathering consistent data in local areas and in large offshore routes. Data are used to study the spatial and temporal distribut...

Systematic data collection of cetacean and seabird distribution in offshore waters is challenging due to the high costs of performing oceanic surveys. Opportunistic platforms such as ferries have proven to be effective in gathering consistent data in local areas and in large offshore routes. Data are used to study the spatial and temporal distribut...

Systematic data collection of cetacean and seabird distribution in offshore waters is challenging due to the high costs of performing oceanic surveys. Opportunistic platforms such as ferries have proven to be effective in gathering consistent data in local areas and in large offshore routes. Data are used to study the spatial and temporal distribut...

Passive acoustic monitoring has become an increasingly prevalent tool for estimating the density of marine mammals, such as beaked whales, which vocalise often but are difficult to survey visually. Acoustic cue counts, when corrected for detection probability, can be translated into an estimate of animal density by applying an individual cue produc...

The True´s beaked whale (Mesoplodon mirus, True 1913) is a poorly studied member of the speciose Ziphiidae family. Its distribution in the North Hemisphere is thought to be restricted to the temperate or warm temperate waters of the North Atlantic, while a small number of stranding records from the Southern Hemisphere suggest a wider distribution,...

The True´s beaked whale (Mesoplodon mirus, True 1913) is a poorly studied member of the speciose Ziphiidae family. Its distribution in the North Hemisphere is thought to be restricted to the temperate or warm temperate waters of the North Atlantic, while a small number of stranding records from the Southern Hemisphere suggest a wider distribution,...

1: Effects of salinity as a stressor to aquatic invertebrates 2: Respiratory responses of marine animals to environmental hypoxia 3: Physiological effects of ocean acidification on animal calcifiers 4: Physiological responses of marine invertebrates to thermal stress 5: Physiological impacts of chemical pollutants in marine animals 6: Nitrogen stre...

Diel vertical migration (DVM) facilitates biogeochemical exchanges between shallow waters and the deep ocean. An effective way of monitoring the migrant biota is by acoustic observations although the interpretation of the scattering layers poses challenges. Here we combine results from acoustic observations at 18 and 38 kHz with limited net samplin...

Marine invertebrates at the base of oceanic trophic webs play important ecological and economical roles supporting worldwide fisheries worth millions. There is an increasing concern about the effects of anthropogenic noise on marine fauna but little is known about its effects on invertebrates. Here the current peer-reviewed literature on this subje...

Once considered abundant, the short-beaked common dolphin (Delphinus delphis) in the Mediterranean Sea has been subject to a large-scale decline during the last few decades. Despite considerable efforts in the conservation of this species, to date, only a few conservation measures have been implemented. Furthermore, although Malta is recognized as...