David JiménezUniversidad de Las Palmas de Gran Canaria | ULPGC · IU-EcoAqua
David Jiménez
Phd
About
58
Publications
17,889
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
423
Citations
Introduction
David Jiménez currently works at the Instituto Universitario Ecoaqua of the University of Las Palmas de Gran Canaria as postdoc researcher. David does research in Zoology, Marine Biology and Ecology. His current projects are the 'Angel Shark Project' and 'Rays of Paradise Project' among other different projects related with elasmobranch ecology, biology and projects related with fisheries (recreational and artisanal) and policy implementationimplementation.
Publications
Publications (58)
The angelshark, Squatina squatina, is listed as Critically Endangered on the IUCN Red List of Threatened Species, and remaining populations are highly fragmented throughout its historical distribution. The Canary Islands archipelago in the North East Atlantic has been identified as a uniquely large stronghold for the species. In the present study,...
The angelshark, Squatina squatina , is listed as Critically Endangered on the IUCN Red List of Threatened Species and remaining populations are highly fragmented throughout its historical distribution range. The Canary Islands archipelago in the North East Atlantic has been identified as a uniquely large stronghold for the species. In the present s...
Length-weight relationships (LWRs) were estimated for 15 mesopelagic shrimp species off the Canary Islands (central eastern Atlantic). Total length, cephalothorax length and total weight were taken for individuals collected during three research campaigns using a commercial semi-pelagic trawl net. The most represented families among the collected s...
The African cuttlefish, Sepia bertheloti, is a commercially exploited cephalopod in two productive system areas off West Africa. However, there is a lack of information on its feeding ecology, making it difficult to describe its ecological role (Morocco and Guinea-Bissau). In the present study, we analyse the gastric contents of 1.114 individuals,...
In this study, we explored the feasibility of using the beaks of the African cuttlefish Sepia bertheloti for age estimation and growth analysis. The rostrum sagittal section (RSS) of the lower beak was the most suitable region in the species. It was applied in samples caught off Morocco and Guinea-Bissau between June 2018 and January 2020. A maximu...
Establishing how threatened wildlife are distributed spatially and temporally is essential for effective conservation and management planning. While many shark species are threatened globally, knowledge on sex-specific differences in behaviour and fine-scale habitat use remains limited, hindering the implementation of appropriate conservation actio...
We report the first case of partial albinism in the Critically Endangered angelshark, Squatina squatina. The encounter with this specimen took place while SCUBA diving on the beach of Tufia, located on the east coast of the island of Gran Canaria on 2 April 2021. This is also the first confirmed finding of an albino elasmobranch specimen in the Can...
The presence of spiny butterfly rays, Gymnura altavela, in waters less than 20 m deep off the Canary Islands shows marked seasonality, with relatively high abundances in the summer and autumn. Large aggregations of sometimes hundreds of individuals, primarily females, appear in specific shallow areas of the archipelago and seem to be associated wit...
Percnon gibbesi is a native crab species characteristic of intertidal and subtidal zones of the Atlantic coast of the European Macaronesian archipelagos (Azores, Madeira, and Canary Islands), and probably also in the neighbouring rocky coasts of northwest Africa. P. gibbesi is considered an invasive alien species in almost all of the Mediterranean,...
This is the first study addressing validation of the early growth stages (including the first increment) in the beaks of juvenile cuttlefishes. The age validation in juveniles of Sepia officinalis was performed by comparison of the number of increments observed in the rostrum surface of lower jaws with their true age. A total of 159 individuals wer...
Globally, elasmobranchs have suffered severe population declines and are, therefore, under an urgent necessity of protection, particularly along the Northeastern Atlantic realm. However, a lack of ecological (e.g., abundance) knowledge across this realm limits the implementation of adequate conservation and management actions. Here, we collected 4,...
Canary Islands, in particular Gran Canaria Island, show spiny butterfly ray aggregative behaviour in different beaches, and it seems to be related with the temperature variation.
Telemetry is a technique used to safeguard the misinformation about elasmobranchs, in this case acoustic tags are being used to find out the presence of spiny butterfly ray on the coast of Gran Canaria
The common cuttlefish Sepia officinalis is one of the most important species for cephalopod fisheries in many countries along the Eastern Atlantic and the Mediterranean Sea. Knowledge of the life cycle of the species is essential for understanding of its population structure and promoting sustainable management of the resource. Age and growth studi...
The African cuttlefish Sepia bertheloti is fished on the West African coast, often mixed with S. officinalis and/or S. hierredda. As in other marine fished species, the sustainable management of their populations begins with the understanding of the species life-cycle. Wild-caught samples of S. bertheloti from the same season and two different fish...
Angel sharks are among the most threatened species of sharks globally. Twenty-two species have been identified globally so far, with three species being present in the Mediterranean Sea: Squatina aculeata, Squatina oculata, and Squatina squatina. The Mediterranean populations of all three species have been assessed as Critically Endangered by the I...
Introducción: El tiburón Angelote (Squatina squatina) también conocido como peje ángel en el archipiélago canario, es una especie de tiburón bentónico que se puede encontrar en toda la zona costera de las Islas Canarias. La especie está clasificada, por la Lista Roja de UICN, como en peligro crítico de extinción, debido principalmente a la sobrepes...
Introducción: La Mantelina, Gymnura altavela (Linnaeus, 1758), catalogada como vulnerable en el atlántico y en peligro crítico en el mediterráneo (Lista Roja de la UICN), ha sufrido y un agotamiento importante debido a la presión pesquera en los últimos 50 años, tanto por el sector profesional como por el sector de la pesca recreativo, debido a que...
Batoids, distributed from shallow to abyssal depths, are considerably vulnerable to anthropogenic threats. Data deficiencies on the distribution patterns of batoids, however, challenge their effective management and conservation. In this study, we took advantage of the particular geological and geomorphological configuration of the Canary Islands,...
This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue econom...
• As an increasingly important resource in ecological research, citizen scientists have proven dynamic and cost-effective in the supply of data for use within habitat suitability models. With predictions critical to the provision of effective conservation measures in cryptic marine species, this study delivers baseline ecological data for the Criti...
Three species of Critically Endangered angel shark are present in the Mediterranean with overlapping ranges:
• Squatina aculeata Sawback Angelshark (EN), Esfen Moshaoak-shkatleo (LY)
• Squatina oculata Smoothback Angelshark (EN), Esfen Mobaka-shkatleo (LY)
• Squatina squatina Angelshark (EN), Esfen-shkatleo (LY)
The Mediterranean Angel Sharks: Regi...
Covid-19 pandemic has affected worldwide in many different ways. Fisheries around the world are not an exception due to the long term isolation and the non-activities period suffered. To do an evaluation of its impact on the fishing sectors in the Canary Islands, 87 online and phone questionnaires were carried out between July and September 2020, c...
Notoscopelus resplendens is an abundant myctophid in the region of the central‑eastern Atlantic. As with a majority of other myctophid species, this species performs vertical migration, playing a key role in the oceanic food web and in carbon sequestration. We examined the reproductive biology of N. resplendens based on 579 specimens caught between...
Wales is one of the only places in north-west Europe with regular sightings of the Critically Endangered Angelshark (Squatina squatina) over the last decade. This species is protected in Wales, through inclusion on both the ‘Wildlife and Countryside Act’ and ‘Environment (Wales) Act’ (Table 1), but little is known about its status, ecology or locat...
• The identification and effective protection of nursery areas is critical for elasmobranch conservation. Research on the angelshark (Squatina squatina ) is in its infancy, and is particularly challenging during the early life stages, in part because of their rarity, but also because of their camouflage and cryptic behaviour.
• Focused research on...
Autonomous sailboats are silent surface vehicles which are well suited for acoustic monitoring. The integration of an acoustic receiver in an unmanned surface vehicle has a large potential for population monitoring as it permits to report geo-referenced detections in real time, so that researchers can adapt monitoring strategies as data arrive. In...
Three species of angel shark are present in the Mediterranean: the Sawback Angelshark Squatina aculeata, the Smoothback Angelshark S. oculata, and the Angelshark S. squatina. All three are classified as Critically Endangered.
This Regional Action Plan is designed to focus efforts and will aid in increasing the profile of angel sharks in the Medite...
The Mediterranean is a hotspot of extinction risk for chondrichthyans, making it a priority region for conservation action. Angel sharks are an example of one of the families where all species present in the region are threatened. The Mediterranean Angel Sharks: Regional Action Plan provides a conservation roadmap and acts as a call to action for s...
Abralia veranyi and Abraliopsis morisii were the most abundant cephalopods caught during epipelagic and mesopelagic surveys off the Canary Islands and accounted for 26% and 35% of the cephalopod catch, respectively. Diel vertical migration patterns were observed in both species. At night, A. veranyi was recorded at depths as shallow as 38–90 m, whe...
IUCN Red List Assessment for Angelshark (Squatina squatina)
IUCN Red List Assessment for Sawback Angelshark (Squatina aculeata)
The distribution of the Rough triggerfish, Canthidermis maculata, has been established in the East Atlantic for the west coast of subtropical central Africa, from Cape Verde Islands to Gabon, but with some records also toward Angola. The capture of a single specimen (TL: 289.6 mm) by tuna vessels in the Canary Islands, expand the distribution range...
Abstract Analysis of 322 cuttlebones of Sepia bertheloti caught in the waters of the Northwest Africa showed significant differences in growth between males and females. Morphometric analysis revealed a relatively different cuttlebone growth pattern between sexes, with males presenting faster growth in length to reach larger sizes and females displ...
Recreational fishing shows a growing number of followers, but at the same time it is a difficult fishery to assess, due to the lack of records of the activity and captures. In the present work it has been analysed the information collected from 118 spearfishing tournaments held in the Canary Islands between 2007 and 2017. The number of recreational...
In this paper we consider what may happen to the marine ecosystem of Gran Canaria Island within the 2030 horizon, if fishing strategies different from those currently in place were implemented and we evaluate the effect of, for example, reduction of recreational–artisanal fishing, limitation of catches (e.g. total allowable catches, TAC), or spatia...
In this study, we used a historical collection of photographs taken by recreational fishers from 1940 to 2014, at the island of Gran Canaria, to show both a significant decrease in the mean total length of Epinephelus marginatus and a concurrent change in the composition of captures. Before 1980, the mean total length of fish caught and photographe...
Understanding the details of local and regional extinctions allows for more efficient allocation of conservation activities and resources. This involves identifying where populations persist, where populations may still be present, and where populations may be locally extinct. Three threatened angel sharks occur in the Eastern Atlantic and Mediterr...
A fishing policy oriented to influencing the behavior of recreational fishermen requires, as a first step, an analysis of the variables affecting their fishing habits in order to establish actions aimed at reducing the impact of this extractive activity. The main objective of this study is to increase existing knowledge concerning recreational fish...
La anómala presencia de bancos de ejemplares del tamboril oceánico (Lagocephalus lagocephalus) en Canarias parece haber estar motivada por un calentamiento anormal del agua de mar en el verano de 2017, asociados a fenómenos oceanográficos y climáticos (aumento de la temperatura por encima de 23ºC, disminución del viento, polvo sahariano). En genera...
The presence of Sthenoteuthis pteropus in the Canary waters (between 27º5N-20ºN and
13ºW-18º5W) is related to migratory aspects in the months of July and November, according with an increase in sea surface temperature. The range of sizes found in the study area is associated with a part of the life cycle of the squid, not finding small size or larg...
The Eastern Atlantic & Mediterranean Angel Shark Conservation Strategy has been developed to act as a catalyst for conservation action for the three Critically Endangered angel sharks found in these regions - the Angelshark (Squatina squatina), Sawback Angelshark (S.aculeata), and Smoothback Angelshark (S. oculata).
Angel sharks are among the most threatened fish worldwide, facing regional and global extinction. In Europe, populations of the three Critically Endangered angel sharks ( Squatina aculeata , Squatina oculata and Squatina squatina ) have been severely depleted.
Taking advantage of the last global ‘hotspot’ of the angelshark, Squatina squatina , this...
1. Angel sharks are among the most threatened fish worldwide, facing regional and global extinction. In Europe, populations of the three Critically Endangered angel sharks (Squatina aculeata, Squatina oculata and Squatina squatina) have been severely depleted. 2. Taking advantage of the last global 'hotspot' of the angelshark, Squatina squatina, th...
The Angel Shark Project (a joint project created
by the Universidad de Las Palmas de Gran Canaria, Zoological Society of London, and Zoologisches Forschungsmuseum Alexander Koenig), the IUCN Shark Specialist Group and the Shark Trust organised a four-day workshop in Gran Canaria in June 2016 to develop the Angelshark Action Plan for the Canary Isla...
Catching angels: Habitat use, population structure and growth rates of juvenile Angelsharks (Squatina squatina) in a nursery area
Meyers E1, Jiménez Alvarado D2, Escánez A3, Crespo A3 Barker J4, Marrero J3
1Zoological Research Museum Alexander Koenig (Angel Shark Project)
2EcoAqua, Universidad de Las Palmas de Gran Canaria (Angel Shark Project)
3...
Angel Sharks are among the most threatened fish worldwide, facing regional and global extinction. In Europe, populations of the three Critically Endangered Angel Sharks (Squatina aculeata, Squatina oculata and Squatina squatina) have been severely depleted. Taking advantage of the last global ’hotspot’ of the Angelshark, Squatina squatina, this stu...
The critically endangered Angelshark (Squatina squatina) has suffered a vast fragmentation of its former distribution range, leaving the Canary Islands as a unique “hotspot”. Here, Angelsharks are present all year around, showing a spatial abundance gradient from the easternmost towards the westernmost islands of the archipelago. Local recreational...