Shark Research in Action: PIT 2013

A setting sun means another night on the water.

Guest Blog
By Annie Anderson and Antonia Ash

This past June, researchers, students, and volunteers from all over the world assembled in The Bahamas for the 19th Bimini Biological Field Station’s (aka Sharklab) annual PIT lemon shark tagging program. It was an international affair with this year’s 29 participants hailing from South Africa to Brazil, from the US to the UK, Belgium, and finally France. Despite the blood sucking mosquitos and lightning illuminating the skies above, the crew rallied together to make PIT 2013 a year to remember.

Juvenile lemon sharks in their pen behind Sharklab

PIT stands for “passive integrated transponder,” a little rice-grain sized uniquely coded microchip that is inserted under the skin of the lemon shark. PIT is also used by the researchers to describe the annual 12-night project that is the longest running research project Sharklab conducts.

For the past 18 years Sharklab has monitored the juvenile lemon shark population in Bimini. Scientists assess survival, growth, and mating characteristics of the lemon sharks in two mangrove-fringed nursery areas called North Sound and Sharkland.

PIT lasts for 12 days

Late in the afternoon while tourists strain their eyes across the Caribbean in the hopes of seeing a green flash, the volunteers load up boats, split up into separate netting and tagging teams, and leave the Sharklab in South Bimini for a long, wet night.

Whether at North Sound or Sharkland, it is the tagging boat’s responsibility to ensure all the nets are set at the same time. Once they go in they must be checked every 15 minutes over a 12-hour period from dusk until sunrise.

Working up a shark

Every night we collect a mountain of data. On finding a shark in the net the team immediately removes it, records the time and location of capture, and radios the information to the tagging boat before transporting the shark for a more detailed ‘work up’. The information recorded at this stage is crucial for past and future data comparisons, for example when they are re-captured we can determine how much they’ve grown, who their siblings are (through DNA), their weight fluctuations, and movements from initial capture locations.

After the long and tiring 12-hour cycle and as the sun rises the net boats haul their lines and all head back to the lab for a hearty breakfast prepared by the hard working home crew. All equipment is cleaned and the team then head to bed for a 6 to 8 hour nap before they must wake to start the whole process again.

Check back here tomorrow where we will describe what goes on at North Sound.

The Bimini Biological Field Station Sharklab depends on the efforts of dedicated volunteers to accomplish our research. Since its 1990 inception, the BBFS Sharklab has been host to thousands of volunteers from all over the globe. Annie Anderson blogs at Sharks Need Love.