Paola Andrea Mejía-Falla

Wildlife Conservation Society-Colombia

The deep ocean is the last natural biodiversity refuge from the reach of human activities. Deepwater sharks and rays are among the most sensitive marine vertebrates to overexploitation. One-third of threatened deepwater sharks are targeted, and half the species targeted for the international liver-oil trade are threatened with extinction. Steep pop...

Small-scale fisheries represent the largest source of income and livelihood for communities along Colombia’s Pacific coast, and at least 100 fish species of commercial interest have been recorded in this fishery. The aim of this study was to estimate the Length–weight relationships (LWR) for some of the most frequently captured fish species in smal...

Sharks and rays are key functional components of coral reef ecosystems, yet many populations of a few species exhibit signs of depletion and local extinctions. The question is whether these declines forewarn of a global extinction crisis. We use IUCN Red List to quantify the status, trajectory, and threats to all coral reef sharks and rays worldwid...

The age and growth rate of the giant electric ray, Narcine entemedor, was estimated using growth bands deposited in the vertebral centra of 245 specimens. Differences in size and age distribution were found between the sexes, a pattern that suggests the annual deposition of band pairs, possibly occurring in April. Multimodel inference and back-calc...

Until March 2021, marine Chondrichthyans in Colombia were fishery resources, administered under the Ministry of Agriculture (MinAgricultura) with the fisheries authority had an NPOA Sharks as a guide for their management. After that, and under the Decree 281 of 18 March 2021 issued by the Ministry of Environment of Colombia, a new policy (called th...

An analysis on the species richness distribution of marine sharks and batoids for the Colombian Caribbean and Pacific regions was carried out. A total of 138 species was documented in nearby marine waters off Colombia, including 76 sharks and 62 batoids; 20 species occurred on both coasts with the Caribbean generally having a higher observed richne...

Chondrichthyan fishes are among the most threatened vertebrates on the planet because many species have slow life histories that are outpaced by intense fishing. The Western Central Atlantic Ocean, which includes the Greater Caribbean, is a hotspot of chondrichthyan biodiversity and abundance, but has been characterized by extensive shark and ray f...

Context Rhinoptera steindachneri is the third-most abundant batoid species in the artisanal gillnet fishery of the Gulf of California, but there are limited age and growth data available for management. Aims The aim was to estimate age and growth of this species from vertebral centra of 276 individuals. Methods Two adjusted data sets were construct...

Chondrichthyan fishes are among the most threatened vertebrates on the planet because many species have slow life histories that are outpaced by intense fishing. The Western Central Atlantic Ocean, which includes the greater Caribbean, is a hotspot of chondrichthyan biodiversity and abundance, but is historically characterized by extensive shark an...

Hematological and blood biochemical reference information is important to establish physiological status of freshwater stingray populations and improve care and management protocols in artificial environments. Here, we used a commercial freshwater stingray with high mortality rates in the market (Potamotrygon magdalenae), as an example to understan...

Heterodontus mexicanus

Rhizoprionodon lalandii. The IUCN Red List of Threatened Species 2020

Due to the ongoing and increasing demand for their products, chondrichthyan populations are often subject to intense exploitation by many small-scale and industrial fisheries worldwide. This situation generates an urgent need for conservation and management of many chondrichthyan species. This includes the Eastern Pacific round rays of the family U...

Se confirma la presencia de la raya chupare del Pacífico Styracura pacifica en el Pacífico colombiano. Esta especie junto con S. schmardae en el Atlántico son los únicos representantes de la familia Potamotrygonidae que habitan en aguas marinas y salobres. La distribución confirmada de la especie se limitaba a las costas del Pacífico de Centroaméri...

Hypanus dipterurs red list assessment

Hotspots identification can be used to establish protected or priority areas for conservation at different geographic scales. We aimed to determine if San Andres, Providencia and Santa Catalina Archipelago could be considered as a hotspot of elasmobranch diversity within the Greater Caribbean. For that, we updated the elasmobranch species richness...

The diet of the diamond stingray (Hypanus dipterurus) was quantified based on individuals collected monthly from October 2013 to December 2015 on Espiritu Santo Island in the Bahı´a de La Paz, Me´xico. Of the 473 stomachs analysed, 211 (44.6%) contained food. Analysis of the prey-specific index of relative importance indicated that the diet of H. d...

The aim of this study was to assess the suitability of different vertebrae staining techniques for the visualization and counting of growth bands in tropical species of batoids (Narcine leoparda, Urotrygon aspidura, Hypanus longus, Potamotrygon magdalenae) and sharks (Alopias pelagicus, Carcharhinus falciformis, Sphyrna lewini, Sphyrna corona and M...

The reproductive potential of the shovelnose guitarfish, Pseudobatos productus, was described for Bahía Sebastián Vizcaíno, a bay in the western coast of the Baja California peninsula, Mexico, and contrasted with other commercially important fishing sites for this species. The reproductive cycle of P. productus at this bay is annual. Ovulation and...

The Southern Eagle Ray (Myliobatis goodei) is a medium-sized (to at least 115 cm DW) coastal eagle ray that occurs in the Western Central and Southwest Atlantic Oceans from South Carolina and Florida, USA and Quintana Roo, Mexico to San Jorge Gulf, Santa Cruz, Argentina. It inhabits continental shelves from inshore to depths of 181 m. It is capture...

The Tortugas Skate (Dipturus bullisi) is a medium-sized (to 77 cm total length) demersal skate with a widespread but patchy distribution from the Gulf of Mexico to Pará, Brazil in the Western Central Atlantic. This is a poorly-known species occurring on upper continental shelves and slopes at depths of 185–550 m. No information is available on inte...

The Rough Pygmy Skate (Cruriraja rugosa) is a small (to 51 cm total length) deepwater ray occurring from Florida (USA) to Brazil, including Caribbean and Gulf of Mexico in the Western Central and South Atlantic. This is a poorly-known species occurring on soft bottoms of continental and insular slopes at depths of 251–1,007 m. No information is ava...

The Bullnose Eagle Ray (Myliobatis freminvillii) is a medium-sized (to 106 cm disc width) demersal coastal eagle ray that occurs in the Northwest, Western Central, and Southwest Atlantic Oceans from Massachussetts, USA to the Texas coast of the Gulf of Mexico and from Venezuela to Buenos Aires, Argentina and inhabits continental shelves from the su...

The Smalltail Shark (Carcharhinus porosus) is a small (<150 cm total length) coastal requiem shark that historically occurred in the Western Central and Southwest Atlantic Oceans from the central, western and southern Gulf of Mexico and along the Caribbean coast of Central and South America to the state of Paraná in southern Brazil, not including t...

Antecedentes. El Golfo de California presenta una alta diversidad de organismos marinos y es una de las principales áreas de pesca en México. La pesquería de tiburones y rayas constituye una importante actividad económica con relevancia social. Objetivo. En el presente estudio se estima la riqueza y abundancia relativa (expresada como CPUE), de 15...

The Caribbean Skate (Dipturus teevani) is a medium-sized (to 84 cm total length) deepwater ray that occurs in the Western Central and Southwest Atlantic from North Carolina, USA to Rio Grande do Norte, Brazil, including the Bahamas, Gulf of Mexico, and Lesser Antilles. This is a poorly-known skate that inhabits upper continental slopes at depths of...

The San Blas Skate (Dipturus garricki) is a medium-sized (to 107 cm total length) demersal ray with a widespread but patchy distribution in the Western Central and Southwest Atlantic in the Gulf of Mexico and from Nicaragua to Piauí, Brazil, and inhabits upper continental slopes at depths of 275–475 m. No information is available on interactions wi...

The Hook Skate (Dactylobatus clarkii) is a medium-sized (to 75 cm total length) demersal skate with a widespread but patchy distribution from South Carolina (USA) to Rio Grande (Brazil) including the Lesser Antilles in the Western Atlantic. This is a poorly-known species that inhabits muddy bottoms on continental and insular slopes at depths of 300...

The impact of fisheries on elasmobranch populations has been widely documented; however, baseline information on shark and batoid management remains limited, particularly in tropical areas and in developing countries. The use of precautionary measures and data-poor methods have been recommended as valuable tools to guide the management and conserva...

The aim of this study was to estimate the age and growth parameters of the Panamic stingray (Urotrygon aspidura) of the Pacific coast of Colombia. Vertebral centra were removed from 309 individuals and used for estimation of age. The results of edge type and marginal increment analysis indicate an annual formation of band pairs. The maximum ages es...

Rhinoptera steindachneri is a commercially important, medium-sized, pelagic migratory batoid fish with benthic feeding habits. It has been considered a specialized predator that feeds on molluscs as well as benthic ophiurids and arthropods off the Mexican Pacific coast. Most biological aspects of this species in La Paz Bay are unknown, despite its...

A review and update to the shark and ray species recorded for the marine waters of Colombia was carried out. A total of 206 species had been recorded in the literature, of which 138 species (76 sharks and 62 rays) could be confirmed from museum records, catches, photographs, and videos. No evidence was found for 25 species, but their distribution i...

Se reporta por primera vez un macho maduro de Zapteryx exasperata con ausencia de clasper derecho, recolectado en el Golfo de California. Las observaciones en el sistema reproductivo no mostraron anomalías ni evidencia de cicatrización reciente de la aleta pélvica derecha. Se sugiere que esta condición podría generarse por dos posibles causas: malf...

David's Angelshark (Squatina david) is a small (to 79 cm total length) demersal shark that inhabits soft substrates on the continental shelf and upper slope at depths of 100-326 m in the southern Caribbean from Panama to Suriname. This species is caught in gillnets, trawls, and longlines, all of which are increasing in effort. Based on the level of...

Entre junio y noviembre de 2014 se realizaron muestreos mensuales de pesca artesanal de arrastre de camarón en localidades cercanas a La Bocana (Santa Bárbara-Raposo y Bajo Punta Soldado) y a Juanchaco (La Barra, El Tigre), Pacífico centro colombiano. El arte de pesca usado para captura de camarón consiste en una malla de nylon negro (calibre 40 a...

Background. Teeth can change significantly in shape and size depending on their position in the jaw, age and sex of the organism. Sometimes due to the loss of these teeth, an incomplete description of the dental morphology exists for several batoid species, which makes it difficult to evaluate intraspecific and interspecific differences. Goals. Des...

Rhinoptera steindachneri is one of the most common batoid species in the artisanal gill net fishery of the Gulf of California. In this study we investigated its reproductive biology based on 317 specimens caught in Bahía de la Paz, Mexico. Females measured up to 94.2-cm disc width (DW) and males reached 82.5 cm DW; there were no significant differe...

The objective of the present study was to describe and characterize macroscopic and microscopic aspects of the reproductive biology of the Giant Electric Ray Narcine entemedor, a viviparous elasmobranch targeted by commercial fishers in Mexico. A total of 305 individual rays were captured (260 females, 45 males); all males were sexually mature. The...

This study found that the reef stingray Urobatis concentricus presents a matrotrophic aplacental viviparous reproduction with yolk sac and trophonemata formation. Growth of ovarian follicles occurs asynchronously and continuously with fecundity of three embryos per female. A maximum size of 58·4 cm total length and 37·6 cm disc width was recorded,...

This study reports the size–weight relationships (SWR) for nine batoid species that are frequently fished by the artisanal fisheries in the southern Gulf of California. Analysis included a total of 2,012 specimens, caught from October 2013 to July 2016. The slope values (b) oscillated from 2.80 to 3.56. Growth was isometric for five species and p...

The aims of the present study were to identify the trophic roles of shark and batoid species in a tropical marine food web and to examine how ontogenetic dietary changes affect these roles. Elasmobranch species at different stages of maturity ( juveniles and adults) are distributed at medium and high trophic levels (3.2–4.2), preying on numerous fi...

Para el Pacífico mexicano se han reportado varios casos de anormalidades en elasmobranquios, en los cuales se pueden mencionar embriones bicéfalos, albinismo y anomalías morfológicas; sin embargo, los casos conocidos de individuos con un solo clasper han sido escasos, siendo este trabajo el segundo conocido para este orden. El ejemplar fue capturad...

In this paper, we used two methodological approaches to analyze the structure and function of a trophic web in the temperate coastal lagoon of Bahía Magdalena, Baja California Sur, Mexico, which represents the largest wetland ecosystem along the west coast of the Baja California peninsula. Ecosystem structure was studied using a topological approac...

In order to investigate zoogeographical patterns of the marine elasmobranch species of Colombia, species richness of the Pacific and Caribbean and their subareas (Coastal Pacific, Oceanic Pacific, Coastal Caribbean, Oceanic Caribbean) was analyzed. The areas shared 10 families, 10 genera and 16 species of sharks, and eight families, three genera an...

During 1995, 2001, 2003, 2004 and 2007; we studied the temporal variation in the structure of the elasmobranch assemblage along the Colombian Pacific coast using: the community index of diversity, heterogeneity, equitability, species composition, average catch sizes, and mean trophic levels. A total of 1711 specimens from 19 species (7 sharks and 1...

We studied anatomical and functional aspects of the reproductive system of females of the Magdalena river stingray Potamotrygon magdalenae using microscopic and macroscopic analysis of each organ. Although the reproductive tract was fully functional on both side, the left organs possibly have a greater contribution to reproductive success, because...

p>During 1995, 2001, 2003, 2004 and 2007; we studied the temporal variation in the structure of the elasmobranch assemblage along the Colombian Pacific coast using: the community index of diversity, heterogeneity, equitability, species composition, average catch sizes, and mean trophic levels. A total of 1 711 specimens from 19 species (7 sharks an...

The use of topological analysis tools in marine trophic networks offers a wide range of possibilities to investigate how the different species are involved in the structuring of a network, as well as to evaluate how important they can be in their organization. This approach allows us to identify the importance of the species from its connectivity a...

We examined the age and growth of Urotrygon rogersi on the Colombian coast of the Eastern Tropical Pacific Ocean by directly estimating age using vertebral centra. We verified annual deposition of growth increments with marginal increment analysis. Eight growth curves were fitted to four data sets defined on the basis of the reproductive cycle (una...

Se evaluó el uso de hábitat del aletiblanco Triaenodon obesus, la mantaraya Manta birostris y el tiburón ballena Rhincodon typus en la Isla Gorgona, a partir de 427 inmersiones de buceo y del análisis de 866 fotografías y videos. T. obesus se observó a lo largo del año, y su presencia se correlacionó con profundidades entre 20 y 30m (66.9%), fondos...

The ecotouristic approach to sharks and rays has developed rapidly in the last 20 years. We studied three species in Gorgona Island from 427 dives (2004-2011), including 866 photographs and videos. There was at least one sighting in 34.4% of the dives, and 25.0% of the photos and videos were useful for identification of individuals. T. obesus was s...

This study reports the first bicephalic embryo of smalltail shark Carcharhinus porosus, which was removed from a pregnant female in coastal waters of the tropical eastern Pacific Ocean. The observation suggested that although the individual's body was well formed, the malformation of the head would have affected it survival.

The discusray has been confirmed in Colombia for the Orinoco Basin in the rivers Meta, Inírida, Tomo, Orinoco and low Arauca. This study reports this species, for first time, for the Bita River from a pregnant female captured in March 2009, therefore extending the distribution range of this species in Colombia.

Reproductive aspects of the round ray Urotrygon rogersi were studied based on 2005 specimens obtained in the artisanal shrimp fishery operating on the Colombian Pacific coast. Females reached greater maximum total length (L(T) ), disc width (W(D) ) and mass (M) (38·0 cm, 19·9 cm and 348 g) than males (32·5 cm, 17·0 cm and 165 g). Sex ratio of juven...

Sexual, ontogenic and temporal effects in the diet of Dasyatis longa were evaluated to determine feeding habits and trophic ecology. Numeric indices and the index of relative importance were applied to establish the feeding strategy of the species. Independence of the diet with respect to sex, dry or rainy season and size was evaluated with conting...

Urotrygon rogersi is a stingray of the order Myliobatiformes, with benthic habits and trophic preference for crustaceans, is frequently caught in trawling fisheries. Such frequency could change the morphometric relationships (possible associations between variables) in this species; therefore, the 41 morphometric variables more commonly used in bat...

Urotrygon rogersi is a stingray of the order Myliobatiformes, with benthic habits and trophic preference for crustaceans, is frequently caught in trawling fisheries. Such frequency could change the morphometric relationships (possible associations between variables) in this species; therefore, the 41 morphometric variables more commonly used in bat...

This is the first report of morphological abnormalities in embryos of Roger's roundray Urotrygon rogersi in the Tropical Eastern Pacific. The embryos of two pregnant females caught in artisanal shrimp trawl nets had incomplete, deformed pectoral fins that were separated from the head along the anterior margin. Moreover, one of the embryos presented...

This study evaluated the relationship between body size and geographic range size, measured as extent and volume of occurrence of resident and endemic elasmobranchs of the Tropical Eastern Pacific. Data of body size, minimum and maximum depths, and latitudinal distribution of the species were obtained from the literature. Extent and volume of occur...

This study evaluated the relationship between body size and geographic range size, measured as extent and volume of occurrence of resident and endemic elasmobranchs of the Tropical Eastern Pacific. Data of body size, mínimum and maximum depths, and latitudinal distribution of the species were obtained from the literature. Extent and volume of occur...

The guitar ray Rhinobatos leucorhynchus is commonly caught as by-catch of industrial and artisanal shrimp trawling in the shallow waters of the Colombian Pacific. The biological aspects of this species were studied using 286 animals caught as by-catch between 2001 and 2007. The females were proportionally larger than males, although growth was simi...

The guitar ray Rhinobatos leucorhynchus is commonly caught as by-catch of industrial and artisanal shrimp trawling in the shallow waters of the Colombian Pacific. The biological aspects of this species were studied using 286 animals caught as by-catch between 2001 and 2007. The females were proportionally larger than males, although growth was simi...

The food habits and trophic ecology of Urotrygon rogersi were analysed to ascertain sexual, ontogenetic, temporal and spatial effects on the diet. These effects were examined with contingency tables, simple correspondence analysis and MANOVA. The trophic relationships of the species were determined with Levin's niche amplitude index and Pianka's di...

This is the first report of morphological abnormalities in embryos of Roger's roundray Urotrygon rogersi in the Tropical Eastern Pacific. The embryos of two pregnant females caught in artisanal shrimp trawl nets had incomplete, deformed pectoral fins that were separated from the head along the anterior margin. Moreover, one of the embryos presented...

We built a trophic network based on a matrix of interspecific trophic relationships to assess the role of elasmobranch fishes in shaping community structure of the Gulf of Tortugas in the Colombian Pacific Ocean. We analyzed diet similarities to define trophic components (nodes) – rather than taxonomical groups – in the network. We evaluated the ec...

This is the first report of morphological abnormalities in embryos of Roger's roundray Urotrygon rogersi in the Tropical Eastern Pacific. The embryos of two pregnant females caught in artisanal shrimp trawl nets had incomplete, deformed pectoral fins that were separated from the head along the anterior margin. Moreover, one of the embryos presented...

The presence of the Gorgona guitarfish, Rhinobatos prahli, in new zones of the Colombian Pacific coast is registered. The current unique Colombian record of the species corresponds to its description from Gorgona Island in 1995. This paper gives new information on the species on the tropical eastern Pacific coast; and contributes to the knowledge o...

This report confirms the presence of Tumbes round stingray Urobatis tumbesensis in the Colombian Pacific coast, increases the species richness of the Urobatis genus in the study zone, and considerably extends the known geographic distribution range of this species in the Tropical Eastern Pacific.

A revision of the species of sharks, skates and rays registered for the marine and continental waters of Colombia was carried out; a total of 176 species (88 sharks and 88 batoids) were found. Of these, 63 species of sharks and 58 of skates and rays have been confirmed through photographic records and biological collections, and the remaining has o...

Stomach contents of 131 specimens of five elasmobranch species (Mustelus lunulatus, Dasyatis longa, Rhinobatos leucorhynchus, Raja velezi and Zapteryx xyster) caught in the central fishing zone in the Pacific Ocean of Colombia were counted and weighed to describe feeding habits and dietary overlaps. Twenty-one prey items belonging to four major gro...

A revision of the species of sharks, skates and rays registered for the marine and continental waters of Colombia was carried out; a total of 176 species (88 sharks and 88 batoids) were found. Of these, 63 species of sharks and 58 of skates and rays have been confirmed through photographic records and biological collections, and the remaining has o...

Specimens of Mustelus lunulatus captured in the trawling fishery of a shrimp vessel in the central zone in the Pacific Ocean off Colombia were analyzed. The size, weight, growth pattern, sexual proportion, stages of maturity and diet were determined. The captured specimens were between 50 and 125 cm, the sexual proportion was 1:1, and the isometric...

The specific life history of rays from the family Rhinobatidae includes low fecundity, ovoviviparous reproduction, and few progeny, making the species vulnerable to recruitment in fishing zones. In Colombia, Zapteryx xyster does not have any commercial value but is captured incidentally by small-scale and industrial fisheries in the Pacific. We stu...

Specimens of Mustelus lunulatus captured in the trawling fishery of a shrimp vessel in the central zone in the Pacific Ocean off Colombia were analyzed. The size, weight, growth pattern, sexual proportion, stages of maturity and diet were determined. The captured specimens were between 50 and 125 cm, the sexual proportion was 1:1, and the isometric...

The specific life history of rays from the family Rhinobatidae includes low fecundity, ovoviviparous reproduction, and few progeny, making the species vulnerable to recruitment in fishing zones. In Colombia, Zapteryx xyster does not have any commercial value but is captured incidentally by small-scale and industrial fisheries in the Pacific. We stu...

We present the first record of the electric ray Torpedo andersoni in the Caribbean re- gion of Colombia. One specimen was sighted and photographed in November 2004 in a reef zone of San Andres Island. This record extends the geo- graphic range of this species to the southwestern Caribbean Sea; its only previous reports were from the Grand Bahama Ba...