Habitat Restoration and Management: 2019

Each year of the Project we build on our growing knowledge, adding elements we have found to be important, adjusting our plans, and testing new methods.  In 2019, OSF tadpoles dispersed to all three pools, but were particularly abundant in Pool C, illustrating the critical importance of well designed aquatic connections that were included in the design of Pool C.  Summer rain was also sufficient to maintain aquatic habitat in the pools in 2019, providing more time for more tadpoles to reach metamorphosis. After other parts of Southeast Meadow had dried, we began habitat work, including mowing and removal of reed canary-grass to 1) create a fourth pool (Pool D) on the floating mat, 2) expand seasonal aquatic habitat beyond the floating mat, and 3) better connect each of the pools to egg-laying habitats. We also began an experiment to replace reed canary-grass in seasonally flooded areas with select native species.

OSF hatchlings dispersed by way of the connecting channels designed for this purpose and reached Pool C in large numbers. (April 29, 2019) (Photo copyright S. Nyman)

In 2019, for the first time, OSF tadpoles occurred in Pool B, although they did not reach this pool until May 18. This relatively large OSF (more than 30 mm body length) from Pool B has nearly completed metamorphosis. (July 28, 2019) (Photo copyright S. Nyman)

Our work in 2019 included removing reed canary-grass in seasonally wet areas shallower than where we have created pools. To replace reed canary-grass, we purchased nursery-grown seedlings of suitable native species and planted them in weed-suppressing mats. These mats are made from woven coir (coconut fiber). We are testing whether the native plants will establish and resist reinvasion by reed canary-grass, and eventually spread into adjacent areas (September 6, 2019) (Photo copyright S. Nyman)

 

Aquatic connections, created by removing reed canary-grass, ensure that OSF tadpoles are able to disperse throughout restored habitats. Here the newly completed Pool D (right) is connected to Pool B (left) and surrounded by floating mat with reed canary-grass mowed and thatch removed. Although the mowed grass will grow back next year, the aquatic connections will remain. This should ensure that more tadpoles will find suitable habitats and survive to metamorphosis (October 14, 2019) (Photo copyright S. Nyman)

Native plants that established naturally in Pool C provided hiding cover for OSF tadpoles and young-of-year. Three young-of-year can be seen basking on these plants (August 20, 2018) (Photo copyright S. Nyman)

This adult female OSF appeared in Pool D on September 10, just three days after the pool was created. Remarkably, this same female was observed in other restored habitat at our site in October 2018 (photo copyright S. Nyman)

Here is our old friend in the photo above. We can identify individual frogs by their unique features, particularly spot patterns on the face and along the jaw (the “lip line”). (October 24, 2018) (photo copyright S. Nyman)