Author Affiliation: LCWC

Journal: Unpublished Report

Abstract:

During the period 2019 through 2023, acoustic recorders were used to monitor bat echolocation signals in six locations within the Les Cheneaux Islands (App. 1). The monitoring was conducted to identify trends in bat activity as an indicator of population trends. Overall bat activity has increased in the Les Cheneaux area over the five years, suggesting that there is at least a short-term, two-fold upward trend in bat activity. Average detections per night increased from 276 to 673 across the area during the study period.

 

Abstract:

At the 5 distributed monitoring sites the total number of detections shows an increasing trend over the last 4 years.  At the fixed monitoring site the total number of detections increased by approximately 34% from 2021 to 2022. The number of detections per night increased cumulatively 75% from 2021 to 2022.

Author Affiliation: LCWC

Journal: Unpublished Report

Abstract:

In 2019, 2020, and 2021, Wildlife Acoustics detection meters were used to record echolocation signals in six locations in the Les Cheneaux Islands to monitor local bat activity. The monitoring was conducted in an attempt to identify trends in activity that might reflect on populations. Five of the locations were monitored at specific time frames during the season. A second monitor remained in place at a fixed location throughout the season, roughly April 29th through September 19th. The results were normalized as detections per night for comparison of activity levels at the different locations and comparison of overall activity from year to year. Overall bat activity has increased in the Les Cheneaux area over the last 3 years implying that there is at least a short term trend in bat activity. Area activity rose from 279 detections per night in 2019 to 599 in 2021.

Author Affiliation: LCWC

Journal: Unpublished Report

ABSTRACT: Monitoring of bat calls was discontinued for September and October of 2018.
The Wildlife Acoustics Echometer touch has proven a very useful tool this year. Several driving transect cruises were undertaken as well as a walking tour of Coryell Island during the June through August time period. The total number of echo-location calls detected exceeded 250. Cruising speed during the cruises was limited to 10 to 15 MPH. When a signal was detected, travel was halted to obtain a better signal to noise ratio. Six species of bats were identified by the EMT2 software during the 2018 monitoring period:
Eastern Red
Little Brown
Big Brown
Hoary
Indiana (endangered)
Silver Haired (most recorded)


The bat call recording .wav files obtained were sent to Michael Fishman of Environmental Resource Management for verification of species identification. Mr. Fishman reviewed the recordings free of charge. His assessment in brief is that we do not have Indiana bats in the areas surveyed but Little Browns instead. His assessment is attached in the appendix. Mr. Fishman is also of the opinion that the remaining species identifications are correct. He also made several recommendations for obtaining higher quality recordings in the future.
Wildlife Acoustics does not recommend the Echometer Touch2 for the monitoring of Indiana or Northern Long Ear bats. Meeting the new federal standards for the definitive identification of these two species requires a recommended Song Meter SM4BAT FS Full-Spectrum Ultrasonic Recorder (microphone not included). These units with microphone cost $1000+.

Author Affiliation: LCWC

Journal: Unpublished Report

ABSTRACT: Echolocation signals were recently recorded in the Birge Nature Preserve to monitor local bat activity using a Wildlife Acoustics detection meter. Eight of nine bat species native to Michigan were identified using Kaleidoscope software to interpret recorded signals. The Silver-haired bat (Lasionycteris noctivagans) signals were recorded most frequently, followed by Little Brown Bat (Myotis lucifugus) and the Eastern Red Bat (Lasiurus borealis). The number of signals recorded for a given species does not accurately reflect a specific number of individuals, but signal numbers can be interpreted to indicate the relative population density among species. Data generated during this project will be incorporated in the Les Cheneaux Watershed Council (LCWC) database that is being developed in an attempt to obtain a more accurate assessment of Les Cheneaux bat population densities.

Author Affiliation: LCWC

Journal: Unpublished Report

ABSTRACT: Echolocation signals were recently recorded at the Mackinac Island school grounds to monitor local bat activity using a Wildlife Acoustics detection meter. Seven of nine bat species native to Michigan were identified using Kaleidoscope software to interpret recorded signals. Some signals are difficult for the software to precisely identify, therefore the number of signals recorded is more a qualified than a quantified value. Software interpretations of bat calls during this monitoring period resulted in about 70% of the signals being from the Little Brown Bat (Myotis lucifugus) and 20% of the signals being from the Eastern red bat (Lasiurus borealis). Silver-haired bats (Lasionycteris noctivagans) accounted for about 3% of the detections.

Author: Scott Myers

Author Affiliation: LCWC

Journal: Unpublished Proposal; 2017

Abstract: A survey of Little Brown bats in the Les Cheneaux area will be conducted by the Watershed Council in 2017 to estimate our local bat population. Little Brown bats are the most common bat species in the Islands. Local bat numbers have declined in recent years due, most likely, to a fungal disease called White Nose Syndrome. Volunteers are being recruited to estimate bat numbers throughout the summer and tallies in the fall will be compared to other bat densities around the State to determine if the relative health of our bat population has been affected by the White Nose Syndrome fungal disease. Results will be published on this website, and will include an estimation of the local bat population, population trends, and resident species population estimates.