About This Project
Sharks are known hosts to hundreds of different species of tapeworm parasites. However, we know little about their transmission pathways. Krill and other small crustaceans are keystone species, meaning they are essential to support the biomass of many top marine predators. However, are they the first intermediate hosts for these shark parasites? Using molecular tools, this study will elucidate the role these tiny, yet abundant, organisms play in the transmission of shark tapeworms.
Ask the Scientists
Join The DiscussionWhat is the context of this research?
In 2011, in collaboration with a colleague from the Falkland Islands, we obtained funding to identify parasites from commercial squid species. We published our results in the journal Marine Ecology Progress Series in 2011 (available from my profile at researchgate.net). The larval parasites we identified from squid were tapeworms who complete their life cycle in porbeagle sharks (who feed on the squid). To date, less than 1% of the complete life cycles of tapeworms infecting sharks are known. Since the squid examined feed almost exclusively on krill and other small crustaceans, I am confident that these are the first intermediate hosts (transmit the parasite to squid). Funding for this project would allow me to identify the complete life cycle for these tapeworms of porbeagle sharks.
What is the significance of this project?
Krill and other small invertebrates, such as Themisto gaudichaudii, are at the base of the food chain and support a large biomass of predators, including sharks, fish, marine mammals, and seabirds. Yet, we know very little of their role in the transmission of parasites in marine ecosystems. Understanding which parasites they carry and can transmit via the food chain is essential to the understanding of our marine ecosystems and for development of ecosystem-based management of our fisheries. Furthermore, changes in oceanic currents due to El-Nino or climate change can alter the distribution of these small invertebrates and of the diseases/parasites they carry. Hence, it is important to know what parasites they carry.
What are the goals of the project?
The main goal is to identify parasites of krill and other small crustaceans at the base of the food chain on the Falkland Shelf. I will collect small invertebrates in Nov 2016 and Feb 2017 during Falkland Islands Fisheries Dept research cruises (no cost to this project). My goal is to dissect approximately 25,000 small invertebrates (I expect 1% will be infected with parasites), recover the first stage larvae of the tapeworm parasites, and identify these using their DNA. Larval parasites, especially tapeworm, lack morphological features necessary for their specific identification, hence the use of molecular tools. I will then attempt to match DNA signatures from these parasites to those I have generated from tapeworm recovered in squid and fish (second stage larvae) and sharks (adults).
Budget
Krill and small crusteacens will be collected during scheduled Falkland Islands Fisheries Dept sampling trips in November 2016 and February 2017, hence at no cost to this project. I plan on using specific genetic markers, i.e. the D1-D3 domain of the large subunit of ribosomal DNA (28S) for tapeworms (requires 8 different primers to get full coverage). The parasite larvae will be fixed individually in 100% Ethanol before DNA is extracted using DNA Extraction kits. The D1-D3 domain will be amplified using Polymerase Chain Reaction (PCR) and the PCR product will be either gel purified (using a gel purification kit) or using a PCR purification kit (i.e. ExoSap). Samples will then be sequenced using direct sequencing at an overseas facility (hence the shipping costs; these facilites are not available in the Falkland Islands) and hologenophores (molecular vouchers) will be sent to the New Brunswick Museum to ensure these become publicly available to other scientists.
Meet the Team
Haseeb Randhawa
I was born and raised in Montreal, Canada and completed my BSc in Zoology at McGill University. During my degree, Parasitology was my favourite class and I became fascinated with parasites. Parasitism is the most successful evolutionary adaptation on the planet with more than half the species on Earth having adopted parasitism as a means of life. Simply fascinating! Then, I decided to pursue a MSc in Parasitology at the Institute of Parasitology (McGill University) describing the parasite communities of four skate species in the northwest Atlantic Ocean. During this time, my passion for sharks and skates developed and I continued to nurture my interest in parasites. Combining the best of two worlds, I went on to complete a PhD at the University of New Brunswick (Canada) where I studied the determinants of host specificity in skate parasites in the northern Atlantic Ocean. During the latter stages of my studies, I had the opportunity to join a research cruise in the Falkland Islands to work on the parasite communities of skates off the Falkland Shelf. I completed four years of postdoctoral work at the University of Otago in New Zealand investigating the drivers of parasite diversity and host specificity in sharks and skates. Prior to taking on my current role as fisheries scientist for the Falkland Islands Government, I worked as a Senior Teaching Fellow for the Ecology Degree Programme at the University of Otago for nearly five years. Over the past few years, I have been collaborating with members of the Falkland Islands Fisheries Department on various projects, primarily on using otolith microchemistry to differentiate between different commercial fish stocks; an important aspect in recruiting me to the Department. However, knowledge of parasites in the Falkland Islands Shelf ecosystem, especially those of squid (the main fisheries we manage), is essential to develop an ecosystem-based management approach to fisheries.
Project Backers
- 21Backers
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- $1,819Total Donations
- $86.62Average Donation