Know The Atlantic Sturgeon

 Know The Atlantic Sturgeon 2As we celebrate Endangered Species Day on May 16, we turn to one strange looking creature that is approximately 200 million years old: the mighty Atlantic sturgeon. There are 5 distinct populations of Atlantic sturgeon: the Gulf of Maine (threatened), New York Bight (Endangered),Chesapeake Bay (Endangered), Carolina (Endangered), and South Atlantic (Endangered).

Sturgeon are biologically unique and one of the longest surviving animals, predating Pterodactyls, flowering plants, and Tyrannosaurs. For some reference, modern humans appeared approximately 2.5 million years ago. Sturgeon live in salt water and reproduce in fresh water, making them one of a limited number of anadromous species. 

Sturgeon have five rows of bony plates, or “scutes” on their bodies. NOAA Fisheries Jason Kahn knows a thing or two about these fish. You asked Jason questions during our tweet chat on sturgeon using #ESDaychat, catch up on his answers below!

We sat down with NOAA Fisheries scientist Jason Kahn and he told us a little more about sturgeon and his research.Know The Atlantic Sturgeon 1

What’s a typical day at your job like?
I work with the Endangered Species Act to ensure threatened and endangered species, including sturgeon, are not driven to extinction by human activities. We work with the people who want to undertake projects that may accidentally kill listed species or harm their habitat, and we suggest ways to alter their project to ameliorate or eliminate effects to these species and their habitat. I also work in the field setting gill nets to determine whether Atlantic sturgeon are still found in some rivers they historically occupied. Last fall, we determined there is still a spawning population of Atlantic sturgeon in the York River system.

What kind of research do you conduct?
Atlantic sturgeon were listed in 2012 as five distinct populations segments. One of those distinct population segments was the Chesapeake Bay, where at the time of listing, only the James River was known to support a reproductive population. Last year, as part of a collaborative effort within the Chesapeake Bay, NOAA Fisheries, and the Navy funded research in the York River. For the first time since the Atlantic sturgeon commercial fishery was closed in Virginia in 1974, adult Atlantic sturgeon were captured in the upper tributaries to the York River. With the discovery of this previously unidentified population, there’s an opportunity to improve management of sturgeon in the Chesapeake Bay. Through this research, we aim to identify and quantify adult Atlantic sturgeon, identify and quantify juvenile Atlantic sturgeon, verify spawning is occurring, collect tissue samples to determine whether York River sturgeon are genetically similar to James River sturgeon, and to tag these fish using telemetry tags and passive telemetry receivers to track their movements within the York River system, the Chesapeake Bay, and along the Atlantic Coast. 

What did you study in school? Why did you want to be a fish biologist?
I double majored in marine biology and ecology as an undergraduate and studied ecology for my Master’s and PhD. I’ve known I would be a fish biologist since my dad took me fishing when I was 5 years old. I caught a spot (a common, small saltwater fish), and was fascinated by the fact that I could stand on the beach and look out at this massive ocean. While I couldn’t see any fish anywhere, there was an entire ecosystem that thrived beneath the surface. I loved the mystery that came with fishing because you had to understand fish habitat to know where they would be. Now, sampling sturgeon is much the same; if you don’t understand sturgeon habitat, you’ll never be a successful sturgeon researcher or sturgeon manager.

How do we use technology to study sturgeon?

We use technology in so many different ways to advance our knowledge of sturgeon. We put passive integrated transponder tags in every sturgeon we catch.  These are the same tags often put in pets, which allow us to identify each fish as an individual and allows future researchers who capture that fish to know where else it has been captured. We also understand the sturgeon genome better now than ever before. We take small fin clips from every sturgeon we catch to determine from which spawning population they originated. Recently, side scan sonar has been used to drive a boat up or down a river and count the number of sturgeon that appear on the image. And probably most importantly, we now use telemetry tags and passive telemetry receivers to monitor sturgeon movements along the entire Atlantic Coast. While all of those technologies are amazing, that only scratches the surface of the way technology has been used to better understand sturgeon. More advances are likely to surface in the next decade to help us learn even more.