Behind the Scenes: Taking care of bats and park rangers

The Duck Brook Motor Bridge was the last bridge built to complete the historic motor road system in 1953. The internal hollow structure is a series of concrete frames supporting the concreted deck and the three massive arches that span Duck Brook’s deep ravine.

Library of Congress

Park rangers use this hollow bridge to practice effective and efficient evacuation of employees who might get injured performing work in a confined space.

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Did you know one of Acadia’s bridges has a hollow interior? The Duck Brook Motor Bridge was the last bridge built to complete the historic motor road system in 1953. The internal hollow structure is a series of concrete frames supporting the concreted deck and the three massive arches that span Duck Brook’s deep ravine. Because the bridge is hollow, it is an excellent habitat for bats and entering the bridge requires specific safety training and precautions.

In spring of 2018, bat researchers placed an acoustical recorder inside the bridge to detect what types of bats might live there. The recently recovered recorder did not detect bats but further monitoring might include multiple recorders since the bridge is very large. In the future, wildlife biologists will continue monitoring to help determine if, and how, bats use the bridge.

As for safety, park rangers use the Duck Brook Motor Bridge as a location to conduct confined space training. This training prepares employees for entering other small spaces such as septic systems or a water tower. In the State of Maine, Duck Brook Bridge is one of the most technical confined spaces to enter.