“Mr. Mussel, what’s your trouble?”

Did you know that the Pedlar River is one of only a few rivers where the endangered James Spinymussel lives?

A freshwater mussel is a mollusk, a shelled creature shaped sort of like a clam, who lives in the rocky river bottom of a river. Like all of our native freshwater mussels, the James Spinymussel is a very important species in the aquatic ecosystem as a source of food for other animals and because of its ability to help clean the water. As a filter feeder, the James Spinymussel filters water through its body in order to eat, taking in small particles of organic matter and absorbing impurities as it does so, leaving the water around it clearer and cleaner than it was before.   The mussel is in trouble in many places because of water pollution and habitat degradation caused by human activities.

We're monitoring a population of James Spinymussels in the Pedlar River now! Brian Watson of the Virginia Department of Game and Inland Fisheries, with help from biologists all over the state, took the initial measurements and gathered date on a landmark two-day event in the river in July of 2005.  Dr. Dave Perault's "conservation biology" class from Lynchburg College took a field trip to this official James Spinymussel monitoring site in September of 2005.

All summer long I have been working with Brian Watson of the Virginia Department of Game and Inland Fisheries as his assistant and as an intern. I have been learning many new and exciting things about what Brian does, and recently I had the opportunity to share what I have learned so far this summer with the public. On July 7, 2004 I was lucky enough to attend a Pedlar River Survey with Brian and assist him with one of our routine ‘mussel hunts’. Not many people realize that we have freshwater mussels in our river systems around here, and quite frankly, before I started working with Brian, I didn’t either.

Now, as the assistant of a malacologist, or a biologist who studies mollusks such as mussels, I have a rather interesting and fun ‘job’. A typical day out in the field usually includes me slipping into a wetsuit and snorkel gear, hopping in the river, and snorkeling the day away. Even though it’s my job to assist Brian, it seems more like fun than work to me. Snorkeling for mussels is an interesting process and probably takes more know-how than people realize. First you have to figure out what section of a particular river you’re going to snorkel. After you’ve decided this it is now your job to get in the river and snorkel in order to get a general idea of the size of the mussel populations for that particular section of river. Not only would snorkeling give you an idea of how many mussels are out there, it would give you an idea of how many different species are present in a given area. This assessment is important as it can tell other malacologists how diverse mussel populations are for a section of a particular river. We, at the Department of Game and Inland Fisheries, tend to focus on the rare, threatened, and endangered species of mussels present in a river system. Since we tend to focus more on these species, we can devote a lot of our time into protecting and propagating them. This is accomplished at the Aquatic Wildlife Conservation Center (AWCC) in Marion, VA which I have visited times throughout the summer. I must say that I have been quite impressed with the sophistication of the methods that the biologists there use to ensure that mussels will continue to remain in rivers throughout Virginia and Tennessee for a long time to come.

On July 7th our attention was focused on one species of endangered mussel in particular,  Pleurobema collina, or the James Spinymussel. Before beginning our survey we had to get all geared up in our wetsuits; complete with knee pads, snorkel, dive hood, snorkel mask, and our ‘goody bags’, as I have once heard them called; however, they are no more than a mesh bag used to hold live mussels for safe-keeping while snorkeling. Before getting in the river, Brian began by telling the volunteers a little bit about mussels and giving them a brief explanation of what they were about to watch us do. I imagine that once we began our survey, we got some pretty funny looks from some of the volunteers. We also talked to the volunteers briefly about how to survey for mussels, where to find them, and details about what they look like.

Volunteers shared view buckets, which are no more than plastic wastebaskets turned upside down with the bottoms cut out and plexiglass fastened to the other end to create a tube to look down into the water with. These devices are rather simple to use as you place the plexiglass on the surface of the water and look down the tube to see the river bottom.Once the volunteers felt confident that they knew what they were doing, Brian and I began our survey. We started at a fairly fast run area where the water was too turbid and deep for us to see the river bottom clearly, so we began working our way up to a section of shallow, faster moving riffles. Shallow water is a lot easier to sample since when we survey for mussels, Brian and I need to dig around in the sediment on the river bottom and flip over rocks in order to find them. Sometimes the mussels are wedged down in-between rocks and cobble and are fairly obvious, and other times they are buried in the sediment and you might have to dig a couple of inches in order to get to them. This is our usual process of surveying, and we employed it to see if we could come up with any of the James Spinymussels in this particular section of the Pedlar River.

To our disappointment, we didn’t find a single mussel in this first section. However, we did see some other pretty exciting ‘critters’ including: hellgrammites, caddisflies, mayflies and a variety of snails. So, we kept snorkeling in order to move on to find better mussel habitat and focus our survey efforts there. While I was snorkeling in a rather moderately flowing run, I noticed something that looked rather familiar to me, Leptoxis carinata, or the Crested Mudalia Snail; and, where there are lots of snails, there’s usually mussels. Sure enough I hadn’t snorkeled very far from where I began seeing the snails, when I noticed something that looked very much like a rock, only it wasn’t. It was a mussel, a Villosa constricta, or the Notched Rainbow Mussel. Notched Rainbow Mussels aren’t very big mussels, but they do closely resemble the James Spinymussel in size and shape and can be easily mistaken for the Spinymussel by a person with an untrained eye. Even though the Notched Rainbow Mussel isn’t an endangered mussel like the James Spinymussel, it is still an exciting find nonetheless. I picked it up, assessed that it was a male, put it in my ‘goody bag’, and kept on snorkeling. Not much further up from where I found the male Villosa constricta, I found another one, but this time it was a female. I got excited and thought that this would be a good opportunity to show the volunteers how to tell the difference between a male and female mussel.

After finding these two mussels Brian and I started back to the group so we could show them what we had found. We began by showing the volunteers the differences between a male and female Villosa constricta. It’s relatively easy to tell the differences in the Notched Rainbow Mussel as the shell shapes of the males and females differ. When looking at the male, you’d notice that its shell is more pointed, whereas in females, it is more squared off. After discussing this aspect of the mussels, we continued to discuss general mussel anatomy and their importance to river systems.

After a hard day’s work, it was time to fill out data sheets for each site, which is a routine process at every field outing. These data sheets allow us to write down important information about the sites. Some of this information includes such parameters as: water temperature, air temperature, riparian cover, percent riffle, run, and pool, bankfull width, mean bankfull width, depth of riffles, runs, and pools, and water clarity or turbidity. The different species of clams, mussels, snails, fish, and crayfish are also recorded for each site. Noting which fish species are present at each site is important as different species of mussels need specific fish hosts in order to reproduce. Other information about the sites that are recorded is the types of habitat that various organisms are found in, their relative abundance, and whether there were any juvenile individuals present. This information is very valuable as it can tell Brian and other biologists like him what species of mussels can be found in a river and under what conditions they were previously found.

On July 14th, we were again out on the Pedlar River snorkeling around for mussels. We began our survey right off of county route 643, and right off the bat we were finding James Spinymussels. These mussels are some of my favorite mussels to find, as I think of them as very unique. One special detail about these mussels that makes them interesting to me is that they have a small spine on their shell, which gives them their name. Most of the time it’s broken off and unfortunately does not regrow, but when you find one with its spine still in tact you know that you’ve found a James Spinymussel without a doubt. We were lucky enough to find one with its spine still in tact, which was only the second one like that, that I have seen since I began working with the Department of Game and Inland Fisheries. It seemed that we found most of them in shallow, fast moving runs, usually in areas where the substrate consisted primarily of sand and large cobble.

As we went along, we tagged each James Spinymussel that we found. The tagging process is an interesting process; however it can be tricky, as I found out. The Department of Game and Inland Fisheries has different colored tags for each river system in Virginia and each plastic tag is about a centimeter long with a letter and a number written on it that serves as a code and is unique to each mussel. For example, a tag number for a mussel might be A067, and this would give this mussel its own special ‘identity’. Getting the tags onto the shells of the mussels is the tricky part of tagging and requires some skill. It all seems rather simple, as all you need is a pair of tweezers and a little bit of superglue, but it can be deceiving. You start by taking a tag off of a roll of tags, put a little superglue on the mussel shell, apply the tag, and let the glue do the rest of the work. A rather simple procedure, but it does take some know-how in order to get the tag to stick just right. For instance, you want to make sure that all of the edges on the tag are stuck to the shell; otherwise if the mussel burrows down into the sediment, the tag will pop off. The tags serve their purpose because if the mussel is found again years later, biologists can get a general idea of how much the mussel has grown since it was tagged, as well as gaining other valuable information from this tag.

In addition to tagging the mussels, we usually take length, width, and height measurements on each mussel. We take these measurements using calipers and measure on the longest, widest, and highest part of the mussel’s shell. This, in collaboration with the tags will help biologists see if a mussel has grown any over a certain period of time. We also assess the mussels for gravidity, meaning that we check to see if the females have glochidia or not. These glochidia or larvae are eventually released when a host fish comes along.

We found several James Spinymussels in the first section of the Pedlar that we surveyed, which was from a riffle area to a slow moving run. After finishing with this section we moved further upstream onto the Pedlar Farms property where I found another James Spinymussel in relatively the same habitat as the ones from the first site. The Spinymussel that I found here was wedged in-between two rocks in a substrate of a sand and cobble mix. The water again was a relatively moderate to fast run, but was still fairly shallow. We again tagged this mussel using the same procedures as explained above and released it back into the river as we did the others. In addition to finding several James Spinymussels, we also found several Notched Rainbow Mussels that day.

Finally, after a long day of surveying Brian and I filled out two separate data sheets for these two sites. Even though both of the sites were on the same river, we still treat them as two individual sites as they are far away enough from one another to be considered separate. We again noted various water quality and habitat parameters as well as noting the species of mussels, fresh water clams, crayfish, and fish found. Again, noting the species of fish found is important. Mussels have a piece of tissue called a mantle which plays an important role in their reproduction process. When females are gravid, meaning that their gills are full of glochidia, they display this mantle, which in many mussel species resembles another smaller fish such as a minnow. When another larger, predatory fish comes along and sees the mantle and mistakes it for food, the mussel discharges its glochidia onto the gills of the fish where they grow until they undergo metamorphosis and become juveniles, at which point they drop off of the gills of the fish. Seeing a gravid female mussel displaying her mantle is a rather interesting thing to watch, and I have had the privilege of seeing a female mussel do this.

Overall, Brian and I felt that we had rather productive trips to the Pedlar River as we were successful in finding what we were looking for. It’s a goal of mine and certainly of Brian’s to try and help endangered and threatened mussel populations, such as the James Spinymussels’, to get back to a number that is considered to be a healthy and established population of mussels in a river system. It’s wonderful to see people come out on days such as the event sponsored by the Pedlar River Institute in order to learn about these wonderful and interesting stream ‘critters’ and to have people so interested in helping to improve upon the rivers in which mussels live.