On August 19, 2017, a hatch-year male Bald Eagle was released at Mason Neck State Park in Fairfax County, Virginia. The eagle was rescued in Alexandria in May 2017. Read more about the eagle’s history and rehabilitation here. Prior to release, the eagle was fitted with a GPS transmitter.
At the Center, the eagle was known as #17-1181 – the 1,181st patient admitted to the Center in 2017. Now, the eagle will be known as MN72. “MN” represents Mason Neck, where the eagle was released. The numbers are the last two digits on the transmitter that the eagle is wearing. Each transmitter has a five-digit number written on the side of it in permanent black marker so that the eagle could possibly be identified at a distance.
December 14, 2022: On December 5, Center staff reached out to a biologist with Conservation Science Global, Inc. [the organization that manages the Cellular Tracking devices on our tracked Bald Eagles] to discuss the lack of recent transmissions of Bald Eagle MN72. According to the biologist, the battery voltage and activity levels simultaneously dropped, and recorded temperatures were reduced to ambient levels in early September. After analyzing the data, the logical conclusion was that MN72 had either died sometime during September or dropped his tracking unit. The biologist noted that based on the location of the last transmission from his unit -- Pierreville, Quebec, Canada -- MN72's tracking unit is not recoverable. While we may never know exactly what happened to MN72 and the transmitter, the data that this eagle provided researchers with during the past five years has been extremely valuable.
October 17: During the past 42 days, MN72's tracking unit has not uploaded any new information to the online server. While we can't be certain of the exact circumstances, several possibilities exist to explain this break in data. The tracking unit itself, most likely the solar-powered battery, could have reached the end of its lifespan -- as mentioned in MN72's previous updates, five years of continuous operation is much longer than is typically expected. Alternatively, MN72 could have moved outside of the cellular range that the unit relies on to communicate with the server, even considering his history of remaining in a small geographic range near the Saint- François River during the fall and winter seasons. We'll continue to check his tracking data during the coming weeks and months.
September 22: It appears that MN72’s tracking unit may be experiencing some technical difficulties – the most-recent data point collected was uploaded on September 2. While it’s possible that he flew outside of the cellular range required for the tracking unit to communicate with the online servers, such a large gap in data suggests the unit may be malfunctioning. Most commonly, these GPS transmitters function normally during a time span of several months to several years; in rare cases – like Bald Eagle W20 – the unit may operate for up to five and a half years! As of September 2022, MN72’s unit has been online for five years and one month. We’ll be checking on MN72 during the coming weeks!