[Celia] I'd just like to acknowledge my collaborators.
I especially wanna acknowledge Sarah Nelson,
who is at the Appalachian Mountain Club,
and really, the person who started
this entire Dragonfly Mercury Project
many years ago in Maine,
when she was at the University of Maine.
And I acknowledge my collaborators here,
Christine Gardiner, my lab manager, and Vivian Taylor,
who's in Earth Sciences here, who is also a collaborator.
So, next slide please.
So before we get into
the community science side of all of this,
I just wanna kind of justify
why so many of us spend
a lot of our time studying mercury.
And just in case you don't know,
it is ranked third on the US ATSDR
priority list of contaminants in the US.
It's a toxin that actually affects humans
and wildlife at low levels,
not just at acute exposures.
Pregnant women, children,
and seafood consumers are most at risk,
because really,
our exposure is mostly through consumption of fish;
and 80% of the fish consumption advisories in the US,
which cover many different kinds of contaminants,
80% are for mercury.
And to the right,
you can see the "Alice in Wonderland" image
because that was the exposure of the Mad Hatters
were actually causing them to look mad
from neurotoxicity from mercury,
and the reason that we worry about mercury in fish
is because it bio magnifies
in that lower cartoon, you can see.
It bio magnifies from mercury in water,
which is almost undetectable,
to very high levels in predatory fish.
Next slide please.
So in addition to effects on humans,
we also know that there are exposures,
important exposures and effects of wildlife,
particularly obligate piscivores.
And our very beloved common loon
has been studied extensively
by my colleague Dave Evers and his group,
and they have found that even in the common loon,
there are been detected aberrant incubation behaviors,
lethargy, changes in wing asymmetry,
and body burdens that are related
to reduced numbers of fledged chicks.
So we know that there are,
from our research in general,
that there are detrimental effects
on populations of wildlife.
Next slide please.
So for those of you who don't
spend all your time thinking about the mercury cycle,
I just wanted to give you all a little background
on where it comes from and where it goes, and what it is.
So when we talk about mercury,
we're generally talking about two main forms:
inorganic mercury and organic mercury.
And in organic mercury, we call methyl mercury,
is the toxic and most bioavailable form of mercury,
but it is not the form that is
emitted and transported in the environment.
In the environment,
the two forms of inorganic mercury are elemental.
And since I can't really point to things,
you can look up in the sky, there's an HG0,
the atmospheric form is mostly HG0, elemental mercury.
And then if you look down
toward where the lake is and the stream,
we have HG2 plus, which is oxidized mercury.
And that's the dominant form in water.
It isn't until that oxidized mercury
gets into the water and into areas
that are relatively anoxic,
that that inorganic mercury,
the HG2+ gets methylated
and turned into methyl mercury.
And if you look at the graph on the bottom,
or at least the bioaccumulation factors,
you can see that from one x in water
it goes to 10,000 x in phytoplankton.
So that's a big step of bioaccumulation,
from water to phytoplankton.
And then it just keeps on going up beyond that,
so that the amount that in the far right, in loons,
is 10 million times the concentration that was in water
because of bioaccumulation and bio magnification.
Next slide please.
So dragonflies are what we are using
as a bio indicator of mercury exposure
in our community science.
And this is because dragonflies
occupy a diverse range of freshwater habitats.
They have site fidelity, so that when you find a dragonfly,
and I'm talking about the larvae,
they really represent where you find them.
And so, most of you are probably familiar
with the adults that we see around,
especially in our region,
we see them all over around aquatic habitats.
But as you see on the left,
the lifecycle of the dragonfly,
those adults actually lay eggs on or in water bodies
and then those eggs hatch into larvae,
which is like number three to four,
which can spend about two to three years
in that environment, in that stage of life.
And then later they then molt
and the adults emerge from that larval stage.
So what we are studying,
are using as bio indicators,
are dragonflies in their larval phase.
And you can see on the right,
in the bottom right corner,
you can see these are ones that have been
collected out of some of the habitats
from which our community scientists
have been collecting and measuring
and identifying the species,
or at least the families.
Next slide please.
So all around the country,
this is being done and I'll talk about
the national program in a moment.
But what we see, as you might imagine,
you might ask, well you know,
are there the same species all around the country?
And of course not.
And in fact, there are seven different families
that we pretty much identify;
but really, four of them are what have been
focused on in the Dragonfly Mercury project.
So you can see on the left,
there are all of these regressions
that show the relationship between
what we are calling the Aeschnid Total Mercury,
which is on the Y axis,
and then whatever other family
that is shown in the four panels,
the dragonfly larvae, total mercury.
And what you can see from that is that Aeschnids,
which is one of the families,
the Aeschnids concentrations
are very correlated with the ones
that are in these other families of dragonflies.
And so by having that very linear relationship,
those of us who are actually
looking at national patterns,
are able to convert the concentrations
that are found in these other families
into an Aeschnid equivalent.
And you can see on the bottom graph,
the Aeschnids actually are the highest in concentrations,
compared to the other families of dragonflies.
But it's this Aeschnid equivalent
that allows us to then compare across sites,
using the data that has been generated
in some of the sites where they collected
each Aeschnids and at least one of the other families.
And you can see some of them on the right,
that's what they look like
when they're in their larval phase.
Next slide please.
So, I'm first gonna just talk
about the Dragonfly Mercury project,
which is one a project,
it's a citizen science framework
for monitoring mercury pollution in the US.
And it's really conducted by the National Park Service,
so we have collaborators there,
and very much organized in terms of the data
and receiving the samples and everything,
by the US Geological Survey.
So, next slide please?
So this map just shows you
the National Dragonfly Mercury Project,
which has been going from 2009 to 2019.
And you can see all of the circles
are national parks all around the country,
in which dragonflies have been collected
by community scientists
who are basically visiting those parks.
And then they go out with trained park service rangers
and they collect and learn about this project
and they help to collect the samples.
There's also a number of samples
that are coming from non-National Parks service sites,
but what you can also see from this
is the coloration is an indication
of Mercury deposition in the US.
And what that shows is,
the more yellow-red color shows
higher deposition of mercury in the US
and the blue-green is lower deposition.
And you can see that, actually,
the highest deposition is around
the Midwest and the Gulf of Mexico,
and also up in some of the mountainous areas
in the Pacific Northwest.
But, that said, we in the Northeast
have also received a lot of mercury emissions
and deposition from the Midwest.
And also in the northeast, where we are,
we have some of the more mercury sensitive habitats;
in other words areas where
Mercury gets methylated more readily
and taken up by our ecosystems.
Next slide please.
So the national scale program
has been written up kind of recently, in 2020,
by Collin Eagles-Smith at the US Geological Survey
and a whole bunch of our colleagues.
And this study was quite a massive effort,
to take all of the data
from what was collected over that period of time,
from 2009 actually to 2018
at 457 unique locations,
across a hundred national park service units.
And it really involved more than 4,000 volunteers,
which is pretty remarkable.
And so I'm just gonna show you
some of the findings from this study.
Next slide please.
[Moderator] I'm just gonna interrupt here, Celia,
we're really mandated to stay on track time-wise,
so we just have three minutes left.
[Celia] Oh, because we started like,
-[Moderator] Yeah. -[Celia] five minutes late,
so I will have to, okay,
well why don't I just skip these slides then?
I would suggest you go to the Eagles-Smith paper
in Environmental Science and Technology,
or if you have any questions just let me know.
And why don't we go straight on to the Dartmouth,
so I think it's slide 13.
Yeah.
[Moderator] This one?
[Celia] No, I'm gonna skip these
because there's so little time.
Yeah, go ahead. That one.
Okay, so the Dartmouth Dragonfly Mercury Project
ran from 2010 to just till last year.
And we focused our efforts on taking this program,
which was developed at the University of Maine,
to New Hampshire and Vermont high schools.
And so we collaborated with teachers,
we took students out where they field sampled,
the samples came to us,
and we then also in the last two years,
got funding from FEMC
to expand this particular project out
to some of the national forests.
So, next slide.
So you can see that this is where,
in the last couple years,
our sites were inclusive of schools and national forests,
Green Mountain National Forest,
as well as the White Mountain National Forest.
And we included our schools in that, so keep going.
Next slide.
All of these samples from schools and from national forests
come back to my lab here
and they are re-identified for a taxonomy check.
We run Mercury on a direct mercury analyzer
and we do an inter calibration
with the US Geological survey,
so that the data can go into the national database.
Next slide.
And so this is just
a figure showing some of the data,
and I guess I don't have time
to talk to you much about it,
but we have, on the right side,
data that came in from the National Forests
and National Historical Parks,
there is one site in the Green Mountain National Forest
that's kind of high.
And all the ones that have asterisks
were collected by volunteers with our students
and other volunteers.
Next slide.
Then we had a culminating symposium,
with students coming to Dartmouth,
and I think that was a really kind of seminal event
for many of the students
and they brought all their families.
Next slide.
So the last two examples of this
are one that's in the Merrimack Watershed,
which is run by Sarah Nelson,
who is now at the Appalachian Mountain Club.
And it is run with so many partners,
as you can see on the left there.
And we work with students,
as well as park service,
National Historic sites.
And next slide.
In this particular program,
we're really able to reach
a different kind of community,
from what we were able to work with
up in New Hampshire and Vermont.
It's Lowell and Lawrence, Massachusetts,
our environmental justice communities,
and so we have a much more
diverse population of students
as well as community members
who are involved in this particular project.
And then, I think next slide?
And then the last slide about the projects,
is we've also just expanded in 23 to 24,
up into the Lake Champlain watershed
and we have been working
with the Lake Champlain Watershed Alliance.
And so that is taking this project
to a new region of our region.
And lastly, I must acknowledge,
especially our collaborators,
but also the funding sources
which have been funding different parts
of this overall regional program;
including NIH and Wellborn Foundation,
FEMC as I mentioned earlier,
the US EPA, Parker Foundation,
Lake Champlain Basin Program
and Lake Champlain Sea Grant.
So, I think I used up my time.
And probably have no time for questions,
but feel free to put them in a chat and I can respond.
[Moderator] Yeah, we do have time for one question.
People can leave too,
but we can take one question if anybody has any.
[Audience Member] How reliable do you find
the data that students collect?
[Celia] It's very reliable.
We teach them clean hands, dirty hands technique.
And because dragonflies have so much mercury in them,
not so much, I should say,
it's not like we're trying to sample water,
which has very low levels;
it's not so much of a contamination issue.
And they wear gloves just like we do,
and so the data are very robust.
[Audience Member] Great, thank you.