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Written by Beth Boos, LSU Graduate Student/ Photos by Beth Boos

Hello again, everyone! For the last eight months I have been studying emergent vegetation on Malheur Lake, and it has been an exciting and challenging road. It’s hard to believe how fast time has flown since I started my position back in January with LSU and the USGS Fish & Wildlife Cooperative Unit. We are only in year one of a two-year study, and it has been a constantly evolving journey to try and work towards restoring emergent vegetation on the lake.

I have been working with the refuge to research potential limitations to vegetation establishment and restoration options for emergent vegetation. We initially took an interest in seed bank viability and composition throughout the lake. A greenhouse experiment was set up to allow germination of soil samples from the lake. We also wanted to test the use of exclosures (made of hog wire & hardware cloth) to reduce potential herbivory and wind-wave action. Sheet panels were used to block predominant wind at some of the sites.

We had some exciting preliminary results in the greenhouse portion of the study, where we brought back over 50 soil samples. There was an average of over 7 germinants per sample (bulrush & cattail), and 94% of samples produced perennial emergent vegetation. Some annual species were also seen, including goosefoot and false pimpernel. This is really promising in confirming that there is a viable seedbank at least on the periphery of the lake. Burns High School played an important role in allowing me to use their greenhouse for this portion of the experiment, and I am so grateful to them for their help and support.

The exclosures that we set up to test reductions in herbivory and wind-wave action had highly variable results. We are interested to see how another growing season will affect vegetation survival and expansion. The extreme drought in Harney County has influenced important environmental factors for germination and establishment, including soil moisture. We will continue to evaluate how these factors influence germination and establishment in this dynamic system.

Thanks to Friends of Malheur’s generosity, we had four trail cameras positioned out on the lake to capture both potential herbivory and water dynamics on the lake. Although a lot of pictures were windswept hardstem bulrush, we were able to get a better picture of the wildlife on the lake. Deer, coyotes, and several bird species were seen with the help of these cameras, and we even had a few deer jump into one of our exclosures– that’s at least a three foot jump! There was not an observed presence of waterfowl on our cameras, although we do know that there were geese on the lake at least in late August to September. However, these were not seen in the locations where we had cameras. The geese seemed to prefer to graze near the mouth of the Blitzen River at the edge of the water line.

The cameras also caught some cool water dynamics on the lake. We can see how quickly water can be pushed from a section of the lake from wind action. The pictures below are all from the same day as water is pushed to the north side of the lake, returns midday, and then retreats again. This can give us some problems if we leave the boats in the wrong place, but it really helps us visualize the level of change we can see on the lake even on a daily basis.

We are really excited for year two of the study. Soil moisture (including drought effects) likely played an important role in both the germination and failure of establishment of many young bulrush plants. Environmental conditions in a natural environment are never replicable, so next year we will have the opportunity to assess the lake under new conditions and stressors and broaden our knowledge on the system with the hopes of restoration for the future.

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