Thursday, August 20, 2015

Mussels in the news!

This summer there have been quite a few news reports about water quality in Minnesota rivers and lakes.  Here's a link to a great story about native mussels in the Mississippi River!
http://www.mprnews.org/story/2015/08/16/mississippi-mussels-making-a-comeback

Wednesday, August 12, 2015

Find the Mussels: Video

Last week, the Snake River gave us quite the treat--clear(ish) water! We took the opportunity to capture a few mussels hanging out underwater.  Do you think you can find the mussels buried in the riverbed? Give it a try! 


Thursday, August 6, 2015

Fun Day! Let's go...grocery shopping??

Our summer is almost over!! How did that happen? It went so fast. 

We finished our last push of field work this Tuesday, after a very successful trip back to the Snake River to aggregate some pocketbooks and heelsplitters. We greeted our old friends at Freddie's Restaurant, ate the continental breakfast at AmericInn one last time, upset a very tiny very fluffy white dog at the riverside, and found more leeches in two days than we had in the seven weeks preceding. We finally found the elusive heelsplitters in the shallow water and reeds by the white dog, instead of the deeper pools like we had expected. For the entirety of the summer, I don't think we ever successfully predicted where the mussels we wanted would be. Always keeping us on our toes--what mischievous creatures! (And for those of you that have seen the picture of us on the front page of the Macalester website, we do not agree with the claim that mussels are "unglamorous" creatures. Fascinating, beautiful, overlooked, complex, yes, but never unglamorous!)


The very definition of glamour

We returned to the lab on Wednesday, and because it was Kelly's last day (And the day before Brooke's birthday) we had a "fun day"! Which to us meant, after a delicious and enlightening lunch at Kelly's house where her children revealed all the family secrets, we drove to Target and did some personal grocery shopping. It's what everyone wishes they could do on their fun day at work but are too shy to say, obviously. We finished with a final stop at Nelson's, where we all raised a spoon in Dan's honor before eating approximately a gallon of ice cream each. Good day.

For our final two days, we have quite a lengthy to-do list, including more sediment, data analysis, poster-making, and cleaning out the garage and the beachful of sand in the truck. I'm looking forward to making sense of all the data we've collected and translating it so everyone can understand the important work we've been doing! We are planning on presenting our posters at the Macalester summer research poster session during family weekend, as well as at the St. Croix River Research Rendezvous and possibly the Minnesota State Fair, so check us out at all of these places if you can! We'd love to explain more about what we've accomplished this summer!


The whole crew on the Snake River
(photo credit Macalester Promotional Material)


Thursday, July 30, 2015

Three Cheers for Public Water Access

Do you ever wonder how we actually get to our river sites? It's a legitimate question for sure, and the answer can actually get quite complicated.

According to the DNR, we may legally access Minnesota's lakes and rivers "if public land or a public road right­-of­-way borders the surface of the water or if you have permission to cross private land to reach the surface of the water" (DNR, http://files.dnr.state.mn.us/rlp/regulations/fishing/fishing2015.pdf#view=fit&pagemode=bookmarks).

Bridge overlooking Chippewa River site
 Since nearly 100% of our mussel sites border road bridges that cross over the river, we are usually able to walk down the side of the bridge into the water, which can either be common river-entry points with beaten paths, or the complete opposite, sometimes involving a plethora of poison ivy and thistles to battle through to the water's edge. 

We do often knock on the nearby homes of the landowners that live next to the river to ask for permission though, just in case.
Farmland near Chippewa River site










Entry into Snake River site
In case you were also curious about mussel regulations, we are allowed to work with these cool living (and sometimes dead) organisms because we are granted authority under the Minnesota DNR in the form of a permit to handle them in these rivers. Even then, there are many rules to follow, such as careful avoidance of invasive species spreading, the care of endangered and threatened mussel species, and more!


 If you're super excited about our research and hoping to collect some of your own mussel shells, here's a heads up about the DNR's rules about that:
  • People with a fishing license and children younger than 16 may hand-pick or possess up to 24 whole shells or 48 half shells from dead mussels of species that are not endangered or threatened
  • Shell collection is allowed from May 16 through the last day in February
  •  You cannot take mussel shells from the St. Croix River
  •  You cannot possess zebra mussels
  •  Mussel shells cannot be bought or sold 

 (DNR, http://files.dnr.state.mn.us/rlp/regulations/fishing/fishing2015.pdf#view=fit&pagemode=bookmarks)

Happy Regulations!



 Photo Credits: photo 3, Macalester promotional material

 

Minnesotan Horror Story: Terrors of the Dark, Murky Waters

Minnesota has some beautiful rivers, and no two rivers are ever exactly the same.  There are often flowers blooming along the banks, trees shading the water, and picturesque homes and farms along the meandering waterways. Birds swoop over the water and sing, and dragonflies dart around happily while frogs hop away from your advances. 


Don't be fooled! This is more than a serene view. 


But when you're in the water, everything changes.  

There's a lot of suspended sediment (check out Brooke's post, "You look Mighty FINE with a 'Mudstache'" for more information) in the rivers we've been in, making visibility nonexistent. Once the water gets more than 3-4 feet deep, there isn't even sunlight filtering through the water, no longer making it appear light and warm and safe. It becomes dark. And cold.  You feel alone.  Anything could happen. 

Without vision, your other senses become heightened, but this really only makes things worse.  On the river bottoms, you can hear the clinking of gravel being swept downstream. But is it gravel? Is it actually catfish stalking you? Is it a snapping turtle warming up its snapper? Is it a serial killer chuckling in the depths, waiting for you to fall into a hole? On occasion, you find your vision actually does work, and you come face to face with a fish darting past your mask. 

Then there's your sense of touch.  To search for mussels, there are a couple of techniques--a sweeping motion like a windshield wiper or a more rummaging technique, like you're frantically playing a piano but doing so under the top layer of sediment. Either way, your hands seem to be magnetically attracted to half-buried objects that should not be there, like farm equipment, glass, your fellow project-mates' boots, or weird cloth bundles.  

For some reason, it is impossible to not let your mind go to the worst possible place--buried bodies, dismembered animal skeletons, or fecal matter. Around rocks, you undoubtedly picture gigantic, aggressive, ferocious crayfish ready to claim your fingers or monster fish that might swallow you whole. On top of it all, minnows like to satisfy their curiosity by lightly nibbling any exposed skin. It's a strange feeling. 

Our timed searches looking for the species richness and abundance at different sites take 20 minutes.  While finding mussels is absolutely the goal, survival is also a goal.  The best way to get through the time is to try and NOT think about any of the things above: what you're feeling (unless they're mussels), what you're hearing, and definitely not what you can't see.  Singing, daydreaming, and repeating "mussels! mussels! mussels!" are all great methods of coping.  

Despite all this, hanging out in the rivers is a lot of fun.  Every snorkeling search is an adventure, and the unknown can be super exciting. We never know what to expect. All of us are great at exercising our imaginations. In the end, we always make it through to the next site and with all our fingers attached.  On to another survey! 

Wetsuits or Wet Suits?

This week, your favorite freshwater native mussel researchers were at it again in the Chippewa River near Benson, MN. Since we finished the Chippewa aggregations last time, we instead focused on doing timed searches and gathering sediment samples.

Maya, Clara, and Mark counting mussels



Brooke, Kelly, and Molly (that's me!) measuring water velocity


The water was often high with a strong current, but the team made do, starting at the most upstream site (which theoretically has the smallest amount of water running through it) and working our way downstream. Some sites reminded us of the good ol' days in the Snake River, when our bags were filled to the brim with mussels....

Mussel data collection at the Chippewa River


And others? Nada, zip, the big zero. These sites were a lot of shifting sand, and the mussels had shifted right on out of there, leaving us with mussel graveyards and hungry leeches....

Mussel data collection at the Chippewa River



Maya and Clara warm up on the roadside
 The weirdest thing about this week's trip was the donning of the short wetsuits! We wore legless wetsuits for part of the week, and even shed them completely in favor of our sediment-y swim suits. Which was amazing. We felt so gloriously free in our own skins! The one downside? You get cold. Oh well!



After 3 days of hard work, we succeeded in completing 9 different sites, so we headed home back to the Twin Cities. In the words of Prof. Kelly, "Yay team!"

Eat Like a Local

All demanding field work requires satisfying meals to sustain the incredible energy output. As we have all learned, snorkeling and fighting strong currents all day can really give you an appetite, so our field experience has included many meals in many restaurants.

But which ones should we go to? Since our project is funded by the LCCMR (Legislative-Citizen Commission on Minnesota Resources), we have decided that the best way to use Minnesota's money is to put it back in the pockets of local Minnesotan businesses. As a result, we have become quite the connoisseurs of the "Authentic Mexican Restaurants" of Southern MN, and discovered the best places to grab a cheap, tasty bite to eat ($2 Burger Baskets, anyone?!) The locals are always extremely friendly and willing to talk about anything, from farming's impact on water to China's monetary policies to how we look like we might eat our hands off if we don't get our food in the next two minutes. 


Molly, Brooke, and Maya enjoy their Mexican Flag enchiladas at Authentic Mexican Restaurant in New Ulm, MN

It feels really nice to get to know not just the local Minnesotan mussels, but the townspeople and the landowners adjacent to the bridges and rivers we snorkle in. Talking with people can also give us really valuable information about the river systems and land use changes that might affect or give context to our results. Building local relationships is always important in the scientific research world!



Digesting our food babies after a full lunch at the Coffee Pot Cafe in Alexandria, MN (Now serving Pepsi!)





"Fat Mussels"

Macalester made a promotional video of what we are up to this summer!
Brooke, Molly, Maya and Clara. Photo courtesy of Macalester Promotional Material





A Field Trip to the Belwin Conservancy

Last week, Clara and I had the chance to accompany Dan Hornbach, one of our professors, on a visit to the Belwin Conservancy. The conservancy focuses on outdoor environmental education and is a site for ecology and conservation-based research as well. We went there to install a piezometer, which, put simply, is a device that lets you measure the pressure of groundwater. With multiple piezometers, it is possible to look at the motion of groundwater and see whether it is coming up or going down. Our trip was a little unusual for us because wetsuits weren't part of our uniform; it was a wader day! 

Installing a piezometer was pretty straightforward: we used a post driver to pound a pipe into a creek, and, once it was far enough into the ground, slid in the piezometer (which is basically a pipe with a mesh-covered end in the ground so water can get in but sediment stays out). 

Clara and Dan taking some initial readings from the newly-installed piezometer while rocking the wader look. 

Once we got some initial readings from the new piezometer, we took readings from other ones that have already been installed. We also downloaded weather and water temperature data from stations around the conservancy.  Dan teaches an aquatic ecology course in the fall, and is planning to use some of these data for the course.  Clara and I are actually enrolled in the class, so we were excited to get a sneak peak of what fun things we'll get to learn about!

Maya taking water depth readings. 

Our visit to the Belwin Conservancy was a great opportunity to learn about groundwater and try something new for a day, but we're back to work on mussels, sediment, and the Minnesota River basin! 

You're Looking Mighty FINE with a "mudstache".

hjulstrom.gif
Hjustrom Diagram: http://www.columbia.edu/~vjd1/streams_basic.htm


Hi, Brooke here!

While we are snorkeling in the rivers we often grow a “mudstache” throughout the search. These fashionable features are due to the sediment flowing through the river. The interaction between the velocity of water and the sediment flowing in it is an important one! The energy (determined by the velocity) of the river, determines how much sediment is entrained and suspended - with more sediment suspended, the greater the “mudstaches” we get.

There are two important diagrams that show the relationship between sediment size and energy of the river system.

One is The Hjulström Diagram below shows the relationship of sediment diameter versus water velocity - showing what speed a particle is in transport, being eroded and deposited.   

Another is Shield's diagram. Put simply, this diagram shows at what shear stress is particle is likely to be entrained (or move along the bed or in suspension).

03_shields_diagram.gif

There are three categories of sediment transport; the wash load, suspended load and bedload.

The wash load of a river is the sediment/debris in the river that is carried by the water near the surface. Usually it will not ever deposit.

The suspended load is the sediment that settles very slow, so slow that it also may never touch the bed of the river. It is upheld by turbulence - and is what causes us to get our great five o’clock shadows.

The bedload of a river is the sediment that is transported along the bed. This transport occurs through the saltation, rolling and sliding of the sediment. Saltation is jumping along of a particle along the bed - rolling and sliding are pretty intuitive.

suspended_load_water.jpg


Unfortunately we do not have any images of us with our fancy-staches, but instead is here a picture of Maya as a burrito! We call this a burrito because we wrap ourselves up in a tarp to keep the car somewhat dry when driving from site to site!

DSCF0423.JPG

Monday, July 20, 2015

I'm Pretty "Sueur" There Are No Mussels Here

Since Molly and Brooke conquered the Chippewa early last week, it was my and Maya's turn to join Mark and head to the Le Sueur river to aggregate more mussels for our glycogen analysis. We got up bright and early Friday morning and drove out into the cornfields.

The river that greeted us was noticeably different than the rivers we've seen so far. The current was strong, and there were deep holes you wouldn't want to step into with a weight belt on. There were downed trees everywhere; at one site, they had created a dam that was ~30 meters wide and ~35 meters long! 

In addition, there was so much suspended sediment that there was no chance of spotting anything farther than three inches away from your face! This meant we were forced to feel around for mussels, but unfortunately we caught many more mussel-sized rocks. We were only able to aggregate enough heelsplitters and pocketbooks at one site instead of three.


One of our data sheets. As you can see, we did not find any live mussels at this site (although we did see a softshell turtle!!)


15 years ago, the Minnesota DNR found plenty of mussels at these sites. Where, then, have they gone, and why? Maya and I are really interested in thinking about this question and looking at whether land use changes could be a factor here. 

Because of the difficulty in finding enough mussels, and heelsplitters in particular, our team has decided to change one of our target species from the White heelsplitter (Lasmigona complanata) to the more common Three-ridge (Amblema plicata). Hopefully this will make it easier to complete our research!


Mussels and Fishies: An Underwater Romance

When we’re looking for live mussels in the riverbeds, we often find the weathered shells of deceased mussels. Opening the valves, a slurry of sediment and debris obscures your vision for a moment.  Sometimes, though, we discover that these calcium carbonate skeletons have been claimed--by fish! It turns out that these shells make the perfect nesting site for fish (like darters) to lay their eggs.  


Last week, we visited the Sleepy Eye Creek, and were surprised to find lots and lots of shells nestled among the cobbles and boulders. Many more than usual were filled with little gelatinous-looking beads. After taking some pictures, we were sure to return the shells to the water as to not dry them out too much.



A white heelsplitter shell from the Sleepy Eye Creek with fish eggs.

While the fish clearly utilize the mussel shells to reproduce, the relationship actually goes both ways. Mussels (of the living variety) often need fish to reproduce. Male mussels release sperm into the open water, and female mussels will produce eggs and hold them in their gills until sperm reaches them. Since mussels don't exactly have the means to move about far distances, some mussels use a special part of their mantle to entice fish to come try and take a nibble. Others release little packets, resembling food to the fish. Either way, instead of a meal, the fish are surprised with a mouthful of glochidia larvae, which attach to the fish's gills and hang out until they become juveniles. When they're ready, the juvenile mussels detach, having caught a ride to a new home!


Life cycle of mussels. 
http://molluskconservation.org/MUSSELS/Reproduction.html

Friday, July 17, 2015

What the Glycogen: Chippewa Edition


Glycogen

As we've mentioned, it's been a wet summer. However, whether the weather wants to cooperate or not, we need to prepare each site by grouping and aggregating 10-15 specimens of our target mussel species (the White Heelsplitter and the Plain Pocketbook) for glycogen analysis. 

The glycogen analysis is basically a "how happy/stressed is this mussel?" analysis. While humans store fat in their bodies, mussels store glycogen. Thus, the more glycogen present, the happier and less stressed the mussel is. 


Chippewa River Aggregation Location
The analysis must be done to the mussels in the same time period to get comparable data, so whenever we visit a site, we place our mussel collections in specific locations marked by GPS coordinates, where we will hopefully find them once again. 




Chippewa River Sites

This week, Mark, Brooke and I visited the Chippewa River near Benson, MN. Going in, we had little hope of finding enough mussels for aggregation. Water levels were high, and we often wore two weight belts, and even used small boulders as personal anchors to stay underwater and fight the current! Also, because of the murky water, we had to rely on our sense of touch rather than sight. 

Chippewa River Site
But all our hard work paid off: we were able to find and aggregate enough mussels of both species for 3 full sites! We even found a nice amount of the sneaky White Heelsplitters, which were quite elusive in our Snake and Cottonwood sites.






Mussels buried semi-deep in Snake River substrate


Many species in the Chippewa, especially the Three Ridge and the Plain Pocketbook, were of monstrous size and heavily buried. I don't blame them: either burrow into the substrate or get carried away by the fast current. I think I'll try that next time!











Photos Credits:
Jess Kozarek, picture 3

River Watch!

Molly here!


We’ve definitely begun to settle into a routine these days, but every site is different. We've had the chance to see some pretty amazing (and sometimes downright creepy) wildlife above and below the water. This list includes but is not limited to:
-crayfish
-fish
-poison ivy
-muskrat
-bald eagles
-huge, water-hopping spiders (like I said, creepy)


Dragonfly on Snake River
Story time: As we were working in the Snake, Brooke set her equipment down on a branch sticking out of the water mid-channel. It just so happens that the largest spiders I’ve ever seen liked Brooke’s equipment a lot. When we grabbed the weight belt flinging the spiders away, it was a moment filled with pure adrenaline and yelling, and then shock as we watched the spiders jump off the branch and hop along the water to the shore. I’m pretty sure our mouths were wide open.



You can imagine, though, what years of human habitation near rivers can do. There are also non-living things in rivers, such as:
-broken bottles
-fishing lines
-farming equipment
-bridge materials
-bicycles

Non-natural things can be a little dangerous. We typically wear gloves, and try to slowly move our hands along the river bed as we search for mussels so as not to hurt ourselves. 

All in all, though, what can I say? We are constantly entertained by the job, and I'm glad to be a part of this unique experience!

Snake River Site


Are Two Weight Belts Enough?





Taking Sediment samples in the Snake River at high flow.  Photo courtesy of Macalester Promotional Material.
This past week we got the opportunity to revisit a previous field site - except during a much higher flow! The first time we went out  the river was flowing around 250 cubic feet per second (cfs, or the volume of water moving through the channel), when we visited this week, it was about 550cfs - this made working in the field quite different. There was a noticeable change in the appearance of the river bed - less fine grained sediment and fewer live mussels!




Taking sediment samples during normal flow! Photo courtesy of Jess Kozarek.
When we collect sediment samples, someone sinks to the bottom and scoops up sediment with a cup - this past time the water movement was much faster - pushing the scooper downstream very quickly. I personally like to use Molly’s legs as a anchor!

As water flux increases, the velocity increases. This higher energy allows for more sediment to move along the bed, or become suspended in the water. This fact was very present at this site in the Snake River. When snorkeling, the visibility had decreased greatly from the last time we were at the site - making it harder to find the mussels.



Yay, cookies! Photo courtesy of Macalester Promotional material.
The mussels we did find were few, and often just shells. Where did all the mussels go that we had found there less than a week before? Had the burrowed deeper? Or traveled with the current downstream? Or could we just not see them?






The hard work was all worth it for some Dan’s homemade cookies!







cfs data found at: http://waterdata.usgs.gov/nwis/uv?cb_00065=on&cb_00060=on&format=gif_default&site_no=05338500&period=&begin_date=2015-07-01&end_date=2015-07-08

Wednesday, July 15, 2015

Pocketbook, Pigtoe, or Spike?

For the first week or so (and a little bit even now), looking at the big pile of our collected mussels on the shore was completely overwhelming. How on earth was I supposed to know whether the mussel I was holding was a Round or a Wabash pigtoe? Which one was A. Lig? And are pocketbooks and L. card the same thing? Every scientific name sounded the same, and even worse, all the mussels looked the same. They looked like roundish, flatish rocks.
But! There is hope! Only a couple of weeks in and we can all identify way more species than I thought possible. Here is a quick list of the most common species we are encountering in our fieldwork:


Spike (Elliptio dilatata): This mussel is easy to identify because of its elongated shape, much more exaggerated than most mussels.

Elliptio dilatata


Ligumia recta: Looks extremely similar to E. dil, except that the raised line on each shell starting from the hinge of the mussel, called the posterior ridge, ends on the side of the shell instead of the bottom (in other words, it ends medially instead of ventrally).


Three-ridge (Amblema plicata): By far the easiest mussel to identify-- just look for those ridges! Sometimes there are more than three, however.


Wabash pigtoe (Fusconaia flava): My favorite, it has a wonky shape but is overall much more round than mussels that have a slightly elongated shape. It also has a bright orange foot!

Fusconaia flava

Pocketbook (Lampsilis cardium): Very fat. Very, very fat. So fat. Definitely the most curious- they are the first to open their shells to explore their new surroundings when we gather on the riverbank to sort our catch.

Lampsilis cardium (center) and Amblema plicata (right)


Pink heelsplitter (Potamilus alatus): Named the heelsplitter because of its shark fin-like appendage on its top, which you would definitely not want to step on! They’re also usually much larger than other mussels.


Potamilus alatus


White heelsplitter (Lasmigona complanata): Looks exactly like the pink version, except that its sides are much flatter and not inflated. It can be hard to distinguish between the two. Both heelsplitters can be a bit of a jokester and squirt you with water when you hold them up in the air.


Mucket (Actinonaias ligamentina): If it has no real distinguishing characteristics and just kinda looks like a mussel, I would bet you’re holding a good old mucket.


Leptodea fragilis: Just like the mucket, but really light. Extremely light. Suspiciously light.


Photo credit:
http://www.museum.state.il.us/ismdepts/zoology/mussels/gallery.html?RollID=mussel_01&FrameID=potamilus_alatus677337a
http://wwx.inhs.illinois.edu/collections/mollusk/publications/guide/index/46
http://www.snipview.com/q/Elliptio
Macalester promotional material