Population (Plants)

The effects of Typha x glauca density on biodiversity, habitat complexity, and water quality of Great Lakes wetlands


Great Lakes wetlands are being directly affected by climate change. As temperature, precipitation, and evaporation increase throughout the region, lake levels are likely to experience greater fluctuations. These fluctuations result in an increased susceptibility to invasive species. One invasive cattail, Typha X glauca, has a wide range of tolerance to water level fluctuations allowing it to establish and persist. The objectives of this research were to study if increasing T. X glauca density from channel to interior of marshes affects the abundance and species diversity of larval fish and amphibians, and macroinvertebrates, and if so, whether habitat complexity and chlorophyll a levels differed across increasing T. X glauca densities. Additionally, the directionality of the trap was recorded to test whether there was significant movement in and out of the channel. In order to study the effects of density on biodiversity, habitat complexity, and water quality of northern Michigan wetlands, larval fish and amphibians, and macroinvertebrates were sampled with light traps from June to August 2017. In addition, habitat complexity, chlorophyll a concentrations, and water quality measurements were obtained. The study indicated that average abundance of taxa decreased across increasing densities whereas species and family diversity was highest where density was highest. Differences between study sites and sampling times as well as habitat complexity contributed to these findings.


Objectives were to measure plant growth form diversity, chlorophyll a, and macroinvertebrate, amphibian, and fish diversity and abundance with increasing Typha density.

Sturgeon Bay Plant Pollinator Network Data 2017

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A short term study to assess two methods of data collection of pollinator-plant networks. It was found that data collected on a smaller number of plots throughout the season yielded very results as data collected from a larger number of plots that were only sampled once in a season. Additionally, the critical role of Pitcher's thistle (Cirsium pitchei) on the dune ecosystem was reaffirmed by both methods.


Pollinators were monitored at Sturgeon bay in Wilderness State Park. A 5000 m2 area was selected in the central part of the Sturgeon Bay dune ecosystem for sampling. The 5000 m2 area was split into a grid of 10m x 10m subplots, resulting in 50 subplots. The four corners of the plot are as follows from the northwestern corner in clockwise order: 45°43'16.2"N 84°56'25.7"W, 45°43'16.0"N 84°56'23.2"W, 45°43'12.8"N 84°56'24.3"W, and 45°43'12.8"N 84°56'24.3"W. 6 of these plots were randomly selected to be plots that would be revisited throughout the summer, while the rest were visited only once in a randomly generated order. Data collection days for RP and OTP were alternated throughout the summer.
All flowering plants in a plot were observed for a 10 minutes. Any pollinator that landed on a flower head during this interval was tallied as a pollinator visit. If a pollinator landed, left and returned, this was counted as two visits. Pollinator data was collected from 10am to 3pm throughout the summer.