JESSICA ESCOBAR-PORRAS

Chief Scientist – Volunteer Coordinator

Born in the mountains of Colombia yet I loved to be in the water before I could walk. When I turned 11 yrs old I met the amazing animals that are sharks and never turned back. I did my free diving course at 12 yrs old and SCUBA at age 15. My first dive with sharks was at Gorgona Island, in the Colombian Pacific Ocean in 1994. That same year I landed my first job as a dolphin trainer, which only confirmed what I had long sensed: I wanted to be a marine biologist!

I moved to Hawaii in 1998 where I carried out my studies working with Monk seals, turtles and sharks for 5 years. In 2006, I moved to South Africa to pursue a Masters degree in Catshark population dynamics. This eventually expanded to the field of conservation genetics in Shark populations.

I currently reside in Durban, South Africa, where I am the Chief Scientist at the Blue Wilderness Research Unit. Here I conduct shark research and develop conservation programs for Durban’s Aliwal Shoal. I’m simultaneously completing my doctorate on the genetic population structure of sharks and its relation to their reproductive strategies through the University of KwaZulu-Natal. My main interest is the biology and conservation of Chondrichthyes worldwide and I am carrying out a revision of shark biodiversity in South Africa and the Indian Ocean

About Jessica

  • Hails from: Medellin, Colombia
  • Currently lives in: Durban, South Africa
  • Favorite Place: Kauai- Hawaii
  • Passions: Diving, especially night dives. When that fails, I like to head outdoors and play with Tinto (my dog) in and around the tidal pools.
  • Favorite Shark: Zebra shark – Stegostoma fasciatum

My Research Work

Movement patterns and population dynamics of four catsharks endemic to South Africa

 Escobar-Porras, J (2009) Movement patterns and population dynamics of four catsharks endemic to South Africa 

 
Sharks are particularly vulnerable to over-exploitation. Although catsharks are an important component of the near-shore marine biodiversity in South Africa and most of the species are endemic, little is known about their movement patterns, home range and population size. With an increasing number of recreational fishers this information is crucial for their conservation. The aims of this study were threefold. Firstly, to identify and analyze existing data sources on movement patterns and population dynamics for four catshark species: pyjama (Poroderma africanum), leopard (P. pantherinum), puffadder (Haploblepharus edwarsii ) and brown (H. fuscus). This highlighted a number of shortcomings with existing data sets, largely because these studies had diverse objectives and were not aimed solely at catsharks. Secondly, a dedicated study was carried out for a limited area, testing a number of methods for data collection, and where appropriate the data was analyzed to determine movement patterns and population numbers. Thirdly, the most appropriate methodology for future studies (with similar objectives) was identified, and the results of the study were used to propose a number of conservation measures.All species of catsharks exhibited strong site fidelity and limited dispersal for extended periods. A few individuals did, however, travel distances in excess of 150 km. Significant trends in temporal abundance were not observed, nevertheless, there was some evidence for higher catches from September to December. Population estimates for the study area were low, with P. africanum having the smallest population size while H. fuscus had the highest population size within the restricted study area. Limited movements, high site fidelity and small population sizes emphasize their vulnerability and suggest that catsharks would benefit from no-take marine protected areas.

Parupeneus fraserorum, a new species of goatfish (Perciformes: Mullidae) from South Africa and Madagascar

John E. Randall and Dennis R. King. (2009) Jessica Escobar recognised in publication acknowledgements. Parupeneus fraserorum, a new species of goatfish (Perciformes: Mullidae) from South Africa and Madagascar
 
Abstract. Parupeneus fraserorum is described as a new species of mullid fish from three specimens collected off the coast of KwaZulu-Natal, South Africa in 39–57 m. Five additional specimens taken by trawl in 81 m off southeastern Madagascar are listed as non-type material. This species is most similar to P. chrysopleuron, known from Japan to Western Australia, which differs in having an asymmetrical maxilla, a higher and more pointed first dorsal fin, and larger size (223 mm SL, compared to 166.5 mm)

Residency and Small-Scale Movement Behaviour of Three Endemic Sparid Fishes in Their Shallow Rocky Subtidal Nursery Habitat, South Africa

Peter A. Watt-PringlePaul D. Cowley Albrecht Götz (2013) (J Escobar-Porras recognised in acknowledgements). Residency and Small-Scale Movement Behaviour of Three Endemic Sparid Fishes in Their Shallow Rocky Subtidal Nursery Habitat, South Africa
.
The residency and small-scale movements of early juveniles (<175 mm fork length) of three sparid fish species were examined in the shallow subtidal zone along a 500 m stretch of rocky coastline near Schoenmakerskop (Eastern Cape Province, South Africa). A total of 12 blacktail (Diplodus capensis), 12 zebra (Diplodus hottentotus) and six white musselcracker (Sparodon durbanensis) were tagged using visible implant elastomer (VIE) tags. Underwater observations in four shallow rocky subtidal gullies and adjacent areas were made using snorkelling gear on a total of 37 days spanning 13 field trips over spring low tide periods between January and August 2006. The VIE tagging method was well suited to individually tag small juvenile fish with minimum disturbance. In general, the degree of residency of juveniles in the shallow rocky subtidal zone was species specific and dependent on the size of individuals. Juvenile zebra displayed the highest degree of residency followed by white mussel cracker and blacktail, with re-sightings recorded on 53%, 40% and 10% of observation days, respectively. The high degree of residency by early juvenile sparids renders them vulnerable to localized coastal perturbations and climate change.

Spatial and Temporal Variability in the Larval Fish Assemblage of a Warm Temperate South African Estuary, with Notes on the Effects of Artificial Channelling

(2010) Jessica Escobar recognised in publication acknowledgements. Spatial and Temporal Variability in the Larval Fish Assemblage of a Warm Temperate South African Estuary, with Notes on the Effects of Artificial Channelling
 
Abstract. The composition, abundance, distribution and seasonality of larval fishes was investigated in the permanently open Kowie Estuary on the temperate southeast coast of South Africa. Larval fishes were sampled within the estuary and marina for a period of two years. Samples were collected seasonally at 14 different sampling stations along the main channel and within the artificially-channelled marina by means of boat-based plankton tows. A total of 11 128 larval fishes were collected, representing 23 families and 38 taxa. Clupeidae and Gobiidae were the dominant fish families, contributing 47.0% and 24.7%, respectively, to the total catch. Common species included Gilchristella aestuaria (Clupeidae), Omobranchus woodii (Blennidae), an unidentified blenniid, Caffrogobius gilchristi, Caffrogobius nudiceps, Glossogobius callidus, Psammogobius knysnaensis(Gobiidae) and Solea turbynei (Soleidae) with the other species contributing <1% to the total catch. Catches varied significantly with season and were highest in summer. Estuary-resident species dominated the overall catch (91%). A notable absence of postflexion larvae and early juveniles characterized the artificial channels. This was attributed to the absence of shallow, marginal water habitat, typical of a good estuarine nursery area. The steep walls of the artificial channels reduce refuge areas, increasing predation by larger piscivores.

East Madagascar Current Ecosystem Survey - ASCLME / FAO 2008 Cruise 1

J.O. Krakstad , S. Mehl , R. Roman , J. Escobar-Porras, J. Stapley, B. Flynn, M. Olsen and I.M.Beck (2013). East Madagascar Current Ecosystem Survey – ASCLME / FAO 2008 Cruise 1
 
Following discussion between the ASCLME project, the Nansen Programme coordinator and FAO, the following aims and objectives were decided for the survey.
Aims To establish a baseline for the ecosystem off southern and eastern Madagascar. To establish for the very first time the physical, chemical and biological characteristics of the East Madagascar Current system as a whole, its bifurcation and with special regard to its influence on the ecosystem of the adjacent continental shelf. This current 7 system (including shelf) is one of the least known systems of the world ocean; physically, chemically and biologically. The cruise has been planned to establish a baseline for all three of these disciplines, albeit a once off. It is planned to deploy current meters for long-term monitoring at a later stage to overcome this shortcoming. The ecosystem baseline assessment is expected to be completed with a special survey on the demersal fauna, (fish and benthos) next year.