Thursday, October 17, 2013

Adventures at Old Woman Creek, Sheldon Marsh, and Magee Marsh

An aerial view of Old Woman Creek (Photo credit)
Old Woman Creek

Old Woman Creek (OWC) is a naturally functioning estuary, which is an environment where sources of water with different chemical properties combine. Backflow from Lake Erie into OWC creates a unique habitat for a diverse floral and faunal community. Located in Huron, OWC is a state nature preserve and the only national estuarine sanctuary in Ohio. 


Ben gathers a plankton tow sample from Lake Erie
On the first night of our trip, we went to the beach to get algae samples with plankton tows from Lake Erie and OWC. Plankton towing is an algal sampling method in which a funnel shaped mesh fabric attached to a collection jar is tossed into the water and then dragged across the surface to collect specimens. 




The tow obtained from the estuary had a large quantity of zooplankton (Daphnia). According to Dr. Johansen, depending on the density, the zooplankton can sometimes consume most of the algae from a tow before you take it back to the lab and get a chance to look at it under a microscope! In the samples we found cyanobacteria (Merismopedia and Afanizomenon), a cryptomonad (Cryptomonas), diatoms (Fragilaria crotonensis and Aulocosira gramulata), green algae (Pediastrum), and dinoflagellates (Peridinium and Ceratium). 

 
Alex and Ben are stoked to begin the canoe trip! (Photo credit: Kim Daut)

The next morning, we set off in canoes to explore the diversity of OWC. As we traveled along the creek, we collected algal samples by scraping partially submerged logs and by attaching a plankton tow net to the canoe. Our guide informed us that the plankton tow sample we collected for the OWC research center was only qualitative. For a quantitative measure of phytoplankton, a GPS device is necessary to standardize tow length.

Curran's Lotus Lillies, 1988 (left, Photo credit) The floating-leaf macrophyte, Nelumbo (right, Photo credit: Kim Daut)
One of the first organisms identified by our tour guide was a genus of water lotus called Nelumbo. These plants occupied the open water area of the estuary and were the featured in well-known paintings of the OWC estuary, created by Charles Courtney Curran in the late 1800's. The white water lily (Nymphaea odorata) was another floating macrophyte that we encountered. On the bottom of these leaves, Dr. Johansen pointed out lophotrochozoan worms.

We were able to see the nest of a bald eagle (left) in an open spot near the top of the treeline (Photo credit). The high-pitched rattle of the belted kingfisher (center) was unmistakeable (Photo credit). The great egret (left) uses it's sharp bill to catch unsuspecting prey, such as fish and amphibians, with quick jabs (Photo credit: Kim Daut).

There was a great diversity of avian species present at OWC, which serves as an important nesting ground. Our guide informed us of the incredibly successful bald eagle conservation effort at OWC. Spanning 30 years, the reestablishment project, which involved field work such as climbing trees to get blood samples from eaglets, increased the eagle population from 4 to 250 nests per year. Since the bald eagle population is now thriving, the nest monitoring has ceased and avian research is currently focused on the migration of the sandhill crane. Other exciting bird species that were seen while canoeing through the estuary include, ospreys (Pandion haliaetus), great blue herons (Ardea herodias), belted kingfishers (Megaceryle alcyon), and great egrets (Ardea alba). The distinctive "meow-like" call of the gray catbird (Dumetella carolinensis) was also heard at various locations in the creek. 

In the photo on the left, Phragmites dominates the edge of the estuary. In the photo on the right, our guide explains how coconut logs containing plant "plugs" of native species are being used to combat Phragmites invasion. (Photo credit: Kim Daut)

As we progressed through the estuary, our knowledgeable guide frequently identified Phragmites, a European invasive reed species that was introduced by ballast water from ships. Phragmites has recently been the focus of a great deal of management and restoration research at OWC. Phragmites will disrupt the community by displacing native plants and drying out the wetlands. This alteration results in negative environmental impacts including the acceleration of eutrophication, reduction of open water, and loss of habitat and food sources for many species. This resilient reed is not consumed by other species and does not die off on its own. The success of Phragmites is aided by a high reproduction rate and rhizomes that can reestablish organisms despite damage to other parts of the plant body. Management strategies include burning, mowing with a Marsh Master (a machine similar to a bulldozer), spraying herbicides from a helicopter, and flooding. Of those methods, only flooding with four feet of water was greatly effective, but unfortunately flooding to that degree is not feasible in most situations. After removing Phragmites from an area, restoration is achieved by using coconut logs to replant native macrophyte “plugs” before invasive species have a chance to reestablish their populations. The coconut logs slowly decay and the native species repopulate and restore the community.

Cameron startles nekton into our nets by splashing around with his hands and feet. (Photo credit: Kim Daut)

Following the canoe trip, we strapped on our waders and headed back into the estuary to sample the fish population. The method we used to capture fish specimens involved the use of a large seine net held against the sediment. Two people held poles at the ends of the seine net and walked in unison with the net in a "U-shape" behind them toward another group of people. The other group walked toward the net, disturbing the area and causing fish to swim into the net. Once the pair and group met, the poles attached to the net were brought together and the bottom of the net was gathered so none of the trapped fish could escape. The net was carried back to shore so that the specimens could be identified and placed in a bucket of water for later use. 

As we searched through the seine net (left, Photo credit: Kim Daut), we found emerald shiners (center, Photo credit) and placed them in a bucket (right, Photo credit: Kim Daut), so that the living specimens could be used by the OWC-ERR staff.

The only species of fish we caught in our net was the emerald shiner (Notropis atherinoides). The emerald shiner belongs to the family Cyprinidae, which is composed of carp and minnow species. The emerald green coloration on its lateral sides distinguishes this species of fish. 

These collected macroinvertebrates and pouch snail are in a petri dish with 70% ethanol and ready to be examined under a dissecting microscope.

Macroinvertebrate sampling was accomplished with the use of dipnets. Triangle dipnets were bumped along the bottom of the estuary, stirring up the sediment, and then quickly lifted to the surface to trap organisms. Edges of the estuary with macrophytes in shallow water were excellent areas for macroinvertebrate collection. 

 

Examples of organisms belonging to Bacillaria (Photo credit), Euglena (Photo credit), and Synura (Photo credit).

After fish and macroinvertebrate sampling, we visited the laboratory at the Ohio Division of Wildlife’s National Estuarine Research Reserve (OWC-ERR) to examine our specimens. Using dichotomous keys provided by the research center, algae identification books, our familiar macroinvertebrate guide, and the assistance of resident algal expert Dr. Johansen, we were able to achieve finer taxonomic identification for our samples. One of the highlights of our algal identifications included Bacillaria, the "accordion-like" diatom (Bacillariophyta). A colony of these pennate diatoms will slide back and forth with an appearance similar to an accordion. Among our samples were the familiar genera of Euglena (Euglenophyta), which possess a red "eyespot" and Synura (Syurophyta), which have distinctive siliceous scales. 

 
Examples of species from Gerridae (left, Photo credit), Corixidae (center, Photo credit), and Coenagrionidae (right, Photo credit)

A hemipteran (true bugs) commonly called a toe-biter was found in a dipnet catch. Toe-biters, or the giant water bugs, are members of family Belostomatidae and in addition to feeding, can use their piercing mouthpart to inflict a painful bite to humans. Some of the other macroinvertebrate families collected included members of Gerridae (water striders), Corixidae (water boatmen), and Coenagrionidae (narrow-winged damselflies).

 
Water quality testing equipment

During our time at the research center, we were able to take a behind the scenes tour of the facility and find out a little more about the research currently taking place at OWC. During our canoe trip we were cautioned not to bump into the expensive water monitoring equiment throughout the estuary. Our guide explained that those instruments measure water conditions and transmit information to the National Oceanic and Atmospheric Administration (NOAA). We were also shown laboratories where chemical properties of water, such as dissolved oxygen (DO) and pH are measured. Our guide stressed the importance of biomonitoring and how phytoplankton is an indicator of community health, as primary producers impact on all levels of the food web above them. The water samples collected from that morning produced a DO value of 8.1 for the lake and 6.3 for the estuary. The amount of DO can vary with sunlight due to photosynthetic activity, so the cloudy conditions of the morning most likely affected the DO value of our sample.

Sheldon Marsh

 
Sheldon Marsh

Sheldon Marsh State Nature Reserve is located in Erie County. As we learned in lecture, marshes are a type of wetland that represents a transitional zone between aquatic and terrestrial habitats. Marshes are characterized by the presence of herbaceous plants. 



 An interesting feature of the marsh was the barrier beach. A piece of land perpendicular to the shoreline protects the lagoon from the harsh wave action of the lake that can be produced during storms. Plants, such as purple sand grass (Triplasis purpurea), which is unique to the barrier beach, are able to survive in this environment because of the protection provided by the barrier. 

Zebra mussel shells were easy to identify due to their characteristic striped pattern.
Invasive zebra mussel shells were also found on the shore of the beach. As we learned in lecture, zebra mussels are contributing to the toxic blooms of Microcystis by selectively consuming diatoms, which compete with Microcystis, from the phytoplankton, while rejecting the cyanobacteria. With reduced competition from diatoms and available phosphorus, Microcystis can form blooms.  

 

A common carp (Photo credit)

While exploring the marsh, we came across a wildlife viewing enclosure that shielded organisms from seeing us so that we could observe their behavior. Turbulence in the water drew our attention, and someone proposed that the disturbance could be due to sparring snapping turtles. Unfortunately, after closer examination, we discovered that the activity at the surface was just an invasive carp splashing around. Like the emerald shiner that we caught in our seine net at OWC, the common carp belongs to the Cyprinidae family.

 
Sheldon Marsh

Immediately adjacent to Sheldon Marsh is the Sawmill Creek Resort Golf Course. We discussed the detrimental environmental effects of the chemicals that are used to maintain golf courses and how the run-off from fertilizers can enter the wetlands. As we learned in lecture, wetlands are fortunately able to function as buffers from this type of nutrient input and prevent its spread through the watershed.

Magee Marsh

 
Magee Marsh

Magee Marsh is located in Oak Harbor, OH. The marsh is a popular spot for birders because of the large amount of migratory birds that use the area as a pit stop. Although the boardwalk was closed for controlled waterfowl hunting, we did get to check out the nature center and take a lap around one of the loop trails. The nature center was very informative and had detailed descriptions of many of the bird species that can be found at Magee Marsh throughout the year. There was also an impressive taxidermy collection of most of the species that can be encountered at the marsh, as well as a few live specimens, such as the blanding's turtle (Emydoidea blandingii) and the common snapping turtle (Chelydra serpentia). 

The brown snake specimen was determined to be male because female snakes typically have a greater taper after their cloaca.

  As we walked around the trail, we noticed native (Typha latifolia) and non-native (Typha angustifolia) cattail species. Native cattails have wider leaves, measuring 1/2-1 in., and adjacent female and male parts. Invasive cattails have more narrow leaves, measuring 1/4-3/4 in., and female and male parts separated by a 1-4 in. gap.  Since it was rainy and a little chilly, we were surprised when we found two brown snakes (Storeria dekayi) on our hike. We ended our trip with an encounter with a non-native praying mantis that we found on a path. The praying mantis was most likely a female due to its large size.

Our trip to Old Woman Creek rocked!

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