Why is the shortnose sturgeon endangered
The Search for Sturgeon: A Prehistoric and Endangered Fish
They're about a 170 to 200 million years old. It's really
amazing to think that we have this big prehistoric animal right here in our
backyards. This is the Pamunkey River; it's one of the two main tributaries to the
York River
The Pamunkey has a population of Atlantic Sturgeon which were listed as endangered
in 2012, which means that they are at the brink of extinction.
Anytime a species is listed as endangered or threatened, under the Endangered Species
Act, it becomes
all federal agencies' responsibilty to try to minimize our impact on the species
and try to help protect and preserve it where possible.
This is an enormous fish, right; it gets up to 800 pounds.
So from biomass perspective, it's consuming a lot of food,
it fills a large role in the ecosystem because of the size of the fish.
So the Navy does a lot of activities and has a lot
of installations throughout the lower Chesapeake Bay.
And so, when the species got listed as endangered through this area,
the Navy wanted to know, well, where these species
occur, what time of year they're here, and
where they overlap with their training and testing activities.
Within this river, any project that takes place, whether it
be the Navy or the Nuclear Regulatory
Commission or the Corps of Engineers, we want to make sure that whatever projects they
have to undertake to help society in general that we don't wipe out a species in
the process.
So we did some research and started working with Chris Hager in
Chesapeake Scientific. And our main interest was putting transponders into these
fish
So we can can track their movements.
So when we get out in the morning, we put out usually three to four different sets
of gill nets. We string them all the way across the river. What we do is we
check the nets every hour to make sure that the fish aren't in the net for too long they
don't get stressed out. And if we catch a fish, we bring it over to the bank and
keep it in the river the whole time. We put passive integrated transponder tags
in it and they also put a t-bar tag which is just a simple external identifier
tag so we can see that we've caught it before so we can release it quickly
if we catch it again. And then we also sometimes put telemetry tags in
The telemetry tag sends out a ping, and so that way, we can follow the movements of
these fish over about four to five year period.
Through this system we can tell when they came into the mouth of the bay,
when they came... did they come from the south, did they come from the north, which way did
they come into the
bay, because we've got two lines of receivers out there in the ocean,
one going north, one going south, so you can actually sort of piece together
the track of how they got here.
We can track their movements and see where they're going
what time of year they're utilizing different locations in the bay,
and how those different areas overlap with the Navy's activities and that gives
us
the ability to then turn around and adjust our activities in terms of timing
or whatever to try to avoid having an impact of these species.
So, the Pamunkey River is actually a really interesting area to be working because
it's such a small river that you can catch almost every fish that comes up.
You actually get to know each individual fish. And so you can monitor the
behavior of an entire population and you can see whether they're coming back
every year or every other year
you can see the changes in growth rates that you might have within the population,
So, we're learning quite a bit about Atlantic Sturgeon and their behavior for this
river and we hopefully can extrapolate that out to other rivers as other scientists
figure out that their fish are doing the same thing. Having these species here
and having them go back to their historic abundance is really important
to the overall ecosystem function.
