What Lurks Beneath the Surface

The Halloween Edition!!!!!

This creepy, crawly Halloween blog contains information provided by the James Sulikowski Lab at the University of New England. 

On Thursday October 25th, James Sulikowski and a team of 5 students went out on the Llyr, a UNE research vessel, to our favorite sturgeon grounds, a spot in between the jetties at the mouth of the Saco River. With a suite of 5 nets, we caught a total of 14 Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus). The largest sturgeon we caught was brought back to the lab and is being housed in one of the MARC tanks (the tank Noodle had been swimming in), and can be seen from the windows on the upper floor of the Marine Science Center.

Historically, sturgeon have been fished for both their meat and caviar, however, their populations could not withstand the fishing pressure. They are now protected under the Endangered Species Act where Atlantic sturgeon are classified as threatened in the Gulf of Maine and endangered everywhere else in their range, while shortnose sturgeon are endangered everywhere. Because of this status, the more we can learn about these fish – the better!

Our lab is actively working to better understand these fish by looking at size, diet, movement and physiology of the sturgeon we catch in the Saco River. Before they are released, all of our sturgeon are given a full “work up” which includes an internal tag (PIT) an external tag (Tbar), 5 different size measurements (see below), a DNA sample and a blood sample. These 2 tags will help us (or other researchers) to identify the sturgeon if it is ever caught again. Some sturgeon are additionally given an acoustic tag. In the river, we have a series of acoustic receivers which can detect every time a sturgeon with an acoustic tag swims by. The receiver will record the exact time that this sturgeon was at that location and we can later collect this data. What’s especially awesome about acoustic tags is that other researchers have receivers in other locations and they can alert us if they ever spot our sturgeon.

In an effort to transfer the sturgeon you now see in the MARC tank to the lab as quickly as possible—and to minimize stress—we haven’t measured it yet and therefore don’t know its exact size; but if I were to guess, I’d say it’s about 6 feet long. Normally, we will set these fish free as soon as we have collected all data points and they have recovered from being handled. However, this sturgeon was brought back to the lab so that we can attach a satellite tag to it. This tag will record pressure and temperature data and store it until the tag pops off, floats to the surface and transmits this data via satellite to us. This sturgeon will be going back in the river soon so make sure to stop by the Marine Science Center and check it out while you can!

Special thanks to Laura Whitefleet-Smith of the Sulikowski Lab for sharing some details about this giant fish.

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