6 Feb

Map of the Week: Tracking Marine Life

Map of the Week: Tracking Marine Life

Marine life can often go overlooked in the eyes of an average person, and that person may rarely stop to think about the abundance of aquatic organisms that are living in the ocean. A company called Ocearch is trying to change this, by helping scientists collect previously unattainable data in the ocean and sharing it with the world.

This map is a screenshot on Ocearch’s interactive map (https://www.ocearch.org/tracker/?list) from 2/6/2019. It shows tagged animals from Ocearch on the East Coast and in the Gulf of Mexico

The data shown in this map indicates the location of marine animals, particularly sharks, that have been tagged by Ocearch. According to their website, “Animals are caught from tenders, using handlines, and are guided by hand in the water to a lift. Once the animals are restrained and hoses of water have been set to enable a continuous flow of fresh seawater over the gills, the science team, made up of researchers and veterinarians, begins its process. Tags such as SPOT, acoustic, and accelerometer are attached, morphometrics are recorded, and samples, such as blood and tissue, are collected.” (OCEARCH) Once tagged, these sharks can be pinged each time they come to the surface of the water, where satellites can connect to the on-animal trackers. This is arguably the only way to obtain such detailed information about these creatures, as “the technologies and methods used represent the least invasive means of obtaining the data necessary to fill knowledge gaps regarding sharks.” (OCEARCH) This method of surveying the sharks does not alter their behavior after samples are taken, and it is the least stressful method of surveying for a sharks health. Each shark is sexed, and samples are collected from the sharks that include blood, tissue, sperm, and parasites that are on the animal.

With the information collected, important studies can be conducted to ensure future stability of the species. For example, researchers will assess the reproductive condition of the animal, and the animal’s diet to determine the path that the animal is on. Ocearch also conducts studies of “parasite species presence, abundance, and infection sites in white sharks.” (Ocearch).

Sharks are apex predators in their ecosystem, and are central to a functioning food-chain. They maintain biodiversity in oceans by keeping populations of smaller predatory species in check, and removing sharks would result in the disruption of the oceanic food web. The research that Ocearch is doing will help future generations of shark and other marine species continue to thrive in the world’s oceans.

Ocearch’s research is incredibly important and contributes to actualizing current conservation goals that are lacking this useful information. Several peer-reviewed papers have been published based on Ocearch expeditions and resulting studies, and there are more that are currently in preparation. For example, the company is currently on an expedition to the Southeast coast of the US attempting (specifically the Northwest Atlantic Shared Foraging Area (NASFA)) to observe large numbers of white sharks that are there during the winter months. In doing so, Ocearch seeks to, “increase the sample size of tagged white sharks to get a clearer picture of their movements in the Northwest Atlantic as a continuation of our North Atlantic White Shark study to reveal the life history of white sharks.” (OCEARCH) The studies, once published, become a basis for informed policy and management decisions. Data collected is shared with collaborating institutions and students who request them for their studies.

Source

Written by: Sean Halpin