March 3, 2016

Research

Research interests include;

 

  • Photo identification

photo-idThe spots and stripes pattern of a whale shark is unique to each individual much like the fingerprint of a human being. This whale shark ‘fingerprint’ does not change as the animal grows which means we can monitor the movements of individuals between localities, make estimates of abundance, study population dynamics and evaluate site fidelity. The accepted ‘standard fingerprint’ is the area between the fifth gill slit and the first dorsal fin as shown in the photograph. We maintain our own photo identification library and newly discovered whale sharks are also uploaded to the Wildbook for Whale Sharks, a Wild Me project engineered by Jason Holmberg which consists of a global whale shark database and visual library of whale shark encounters. The database is maintained by marine biologists and citizen scientists from across the globe and the information is used for collaborative research to better understand and protect the species.

 

  • Tagging program

Little is known about where the whale sharks go when they leave the Gulf of California. A number of large, and sometimes even pregnant, females have been observed around Isla Espiritu Santo off the coast of La Paz and Gordo Banks off the coast of Los Cabos. This presence of pregnant sharks together with the nearby aggregation of juveniles in La Paz bay suggests that there is a primary nursery area relatively close by. By placing satellite tags on the sharks we can collect 6 months worth of data to a maximum of depth of 2000 meters. Anything below this depth will cause the tag to be automatically released, helping to ensure the safe transfer of the invaluable data. It is thought that whale sharks make dives well below 2000 meters. For what reason is unknown and present technology does not allow us to follow the whale sharks any deeper.

 
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  • Injury analysis

It is common knowledge that over 60% of the whale sharks in La Paz bay have visible boat-caused scarring . Often when new, un-scarred sharks are identified in the bay, later encounters show that some are inflicted with boat injuries within weeks or months of their arrival. The injury analysis data, including video footage and photos, give us the opportunity to raise awareness and improve training with local whale shark tour operators. We are looking to back up this study with some behavioural data in the near future (see behavioural studies below).

 

  • jay-drone-sunlightBehavioural studies

Tourism has the potential of causing detrimental effects to the target species and their habitats. In the case of the whale shark tourism industry in the Gulf of California, concerns have been raised about the ecological sustainability of the practise due to direct disturbance to the animals’ natural behaviour. We are in the process of devising a study that will use various observational platforms to give us a better insight into potential or actual negative impacts that tourism may have on the behaviour of our local whale shark population.