A Weekend at Old Woman Creek

On Friday afternoon, the Aquatic Resources class from John Carroll left for the Old Woman Creek Research Reserve in Huron, Ohio. The goal for the weekend was to sample the water for algae, to sample the macroinvertebrate communities, and to learn about the greater wetland community in the area.  We also had the opportunity to seine for fish and to visit nearby wetlands. 

Areas outlined in red belong to the Old Woman Creek National Estuarine Research Reserve

    The Old Woman Creek Research Reserve is a member of the National Estuarine Research Reserve System (NOAA). It is unique because it is one of the only freshwater estuaries in the system. Usually people think of estuaries as places where saltwater and freshwater mix, but in this case, Old Woman Creek mixes with Lake Erie.  Even though theses are both freshwater systems, they have different water chemistry and where they mix provides another type of habitat. The Old Woman Creek estuary is an important area to preserve and study because it is still a naturally functioning estuary. Many other estuaries on Lake Erie have manmade features, such as breakwalls, docks, and channels, which have been added for recreation or industry. These structures change how the estuary functions. It was a great opportunity to be able to visit a natural estuary and see how the system works first-hand.

View of estuary and Lake Erie

   On Friday night, the weather was nice with temperatures in the mid-60s and sunny skies. Right after we arrived, we sampled for plankton in Lake Erie, as well as in Old Woman Creek.  The sampling method used was a plankton tow. A plankton tow is a procedure that involves throwing a funnel- shaped, fine-meshed net into a body of water in order to collect samples of phytoplankton and zooplankton. These microorganisms are used as indicators of pollution, acidification, and concentration of nutrients in the body of water. This collection method was performed in Lake Erie and near Old Woman Creek Estuary. The samples collected were observed using microscopy. 

Plankton Tow

Samples from plankton tow

         The samples obtained were diatoms such as Melosira varians and Gyrosigma. Also, Dinophytes (Gymnodinium and Ceratium), Euglenoids (Euglena) were observed as well as some Green Algae such as Closterium and Pediastrium. The presence of these species indicates that the water quality is tolerable, however the presence of Euglena could indicate an increase in water nutrient concentration.  A large number of zooplankton were seen in these samples, which may have impacted the amount of algae seen under the microscope. Plankton tows are a great way of collecting quick samples of organisms to evaluate the water quality by the presence certain species of phytoplankton and zooplankton and knowing their tolerance to pollution.

View of Old Woman Creek

         On Saturday morning, we met with a staff member of the research station to go canoeing on Old Woman Creek. This area provides an important habitat for native fisheries as well as being an important birding area. While canoeing we got to see a Bald Eagle nest, an Osprey and Cormorants. One of the missions of the research reserve is to preserve these habitats. The removal of invasive Phragmites australis along the riverbank has been a challenge. This weed grows quickly and can overcrowd native aquatic plants. Currently, they are spraying Phragmites australis with a wetland-approved herbicide to make it die back, so that they can move in with restoration efforts. Once the Phragmites australis is removed native species are planted in those locations, in biodegradable plugs or pots. This allows the plants to get a steady root system in place.

In this area, native plants have been restored.

 Algae scrapes were performed on Old Woman Creek Estuary while canoeing. Samples were taken from different locations such as floating logs, near shoreline vegetation, under floating lotus leaves as well as near a concrete bridge stand. Other samples were collected using a plankton tow net while canoeing. This would let us examine the plankton and algae from various sections of Old Woman Creek. 

Fish seining in action

After canoeing, we ventured into the pouring rain to trying fish seining. Fish seining is a technique used to catch or collect various vertebrates (fish) using a dragnet. A dragnet is setup across a river stretch and fish are scared into the net by other people upstream walking towards the dragnet. The reason for fish seining is because fish are essential organisms in monitoring water quality. They are extremely vulnerable to changes in water quality, nutrient and oxygen availability as well as temperature and acidification. Scientists use fish as one of the means of monitoring water quality by understanding the preferable environment of a particular species of fish. During fish seining, the only fish collected were emerald shiners (Notropis atherinoides). 

Emerald Shiners

 

Collecting Shiners to send back to the research station

          Dip nets were also used to collect sample of invertebrates along the shoreline of the estuary. Invertebrates are essential bio-indicators. The greater the number of particular invertebrate in a body of water the better the water quality. If the body of water contains a lot of leeches and snails then the water quality is poor; however, if the water contains invertebrates such as Stoneflies (Plecoptera), Mayflies (Ephemeroptera) as well as Odonata species (Dragonflies and Damselflies) then it is safe to assume that the water quality is good. During the sampling process many species were collected such as Water Striders (Gerridae), Narrow- winged damselfly (Coenagrionidae), Dragonfly (Libellulidae) as well as Small Minnow Mayfly (Baetidae) and many more. These are definitely indicator of fair/good water quality. 

After all of the samples were collected they were taken to the research facility to be analyzed. The samples collected were by means of microscopy. Microsopy is an easy way to identifying species of organism by the means of their physical characteristics and then grouping them according to family. The samples collected included examples of organisms from: Sulfur Bacteria, Cyanobacteria, Chrysophyta, Synurophyta, Bacillariophyta, Tribophyta, Green Algae, Euglenophyta, Dinophyta, Cercozoa, Ciliphora, Gastrotricha. A complete list of all identifications is included below.  All of these organisms show the great diversity that is present in Old Woman Creek Estuary as well as indicate the pollution level of a body of water.

Examples of collected species

   

After identifying samples, we went on a tour of the visitor center and research facilities. The visitor center houses lots of exhibits to educate the public about issues of invasive species, native species preservation, and the history of the area.  The research facilities include a microscopy lab, an analytical chemistry lab for testing water chemistry, a radioisotope lab, along with general laboratory space. During the tour, we viewed a demo showing some of the tests used for water sample testing, such as pH and dissolved oxygen. There are some very exciting experiments taking place at the facility. An example of a past study is a paper that looked at the impact of pharmaceutical chemicals in the water. (http://www.csc.noaa.gov/magazine/2010/01/article2.html) 

On Sunday, we went to visit some wetlands (marshes) in the area. A marsh is a type of wetland that is primarily composed of herbaceous plants. They act as transition zones between aquatic and terrestrial habitats and are essential in creating mini environments for many different species. The first location was Sheldon Marsh. Sheldon Marsh is located next to a golf course, and the impacts of the fertilizer runoff is evident in the marsh. In some areas, the water is overgrown with algae and small aquatic plants, which is commonly a sign of eutrophication (excess nutrients in a system). This is a common problem in wetland systems, since they are usually surrounded by developed urban and suburban areas.  Invasive species were prevalent in Sheldon Marsh. Phragmites australis and Typha angustifolia (narrow-leaved cattails) were seen crowding out native cattails and other aquatic plants. These tall invasive species change the marsh habitat, leaving very little refugia and land for the migrating birds. 

Sheldon Marsh

Signs of eutrophication

The second location visited was Magee Marsh, located in Oak Harbor, Ohio. It serves as a home for many different species of plants and animals. During the trip to Magee Marsh we stumbled upon a small baby snake and a mantis. However, the marsh is home to many reptiles (snakes and turtles) and different types of birds (eagles, Canadian geese, waterfowl ,etc.). It also serves as a hunting ground for many people, attracting tourism. During the visit to Magee Marsh, no collection techniques were performed. The marsh serves as a habitat for a diverse array of wildlife, and faces many of the same challenges that were seen at Sheldon Marsh. Because these wetland systems are at risk from human impacts, it is critical that conservation efforts and education about the importance of wetlands continues. 

Magee Marsh

A complete list of species identified over the weekend: