Four Years Continuous Monitoring Reveals Different Effects of Urban Constructed Wetlands on Bats

Abstract

Proactive artificial wetland constructions have been implemented to mitigate the loss of wetlands and their ecosystem services. As wetlands are habitats for bats, short-term (one or two years) studies find that constructed wetlands can immediately increase local bat activity and diversity. However, it is not clear how constructed wetlands affect bats through time while the wetlands are aging. We collected four years of continuous bat acoustic monitoring data at two constructed wetlands in an urban park in Greensboro, NC, USA. We examined bat activity and community composition patterns at these wetlands and compared them with reference sites in the city. With four years of data, we found that the effects of constructed wetlands were both habitat- and species-specific. The wetland in forests significantly increased bat activity, while the wetland in the open grass altered bat community composition. Specifically, in terms of species, we found that over time, constructed wetlands no longer attracted more big brown, silver-haired, or evening bats than control sites while the wetlands aged, highlighting the need to study broadly how each bat species uses natural and artificial wetlands. We emphasize the importance of long-term monitoring and the periodical evaluation of wildlife conservation actions.

Predator-Prey Relationship between Urban Bats and Insects Impacted by Both Artificial Light at Night and Spatial Clutter

“…One aspect that our study was not able to address was how interspecific or intraspecific interactions among bats might affect species’ responses to ALAN. When optimal prey sources are available, bats might compete to dominate the prey source [ 81 , 82 , 83 , 84 ]. All species we examined were either open or edge foragers.…”

“…Additionally, the evening bat was the only species in our study that showed no response to ALAN or spatial complexity. Considering this species is generally smaller than other species in the study area [ 55 ] and has been found less competitive with other species [ 81 , 82 ], we suspected that evening bat foraging activity might be opportunistic. Further study should address possible bat community dynamics under ALAN in relation to prey availability.…”

Restoration of boreal wetlands increases bat activity

“…Our study design allowed discrimination between the expected spatial and temporal variation in bat presence and activity, and the effect of the restoration actions. Flaquer et al 2009;Maslonek 2010;Ciechanowski et al 2011;Stahlschmidt et al 2012;Korine et al 2015;Straka et al 2016;Parker et al 2019;Toffoli & Rughetti 2020;Beranek et al 2021;Li et al 2021), while one study investigated the effects of drainage (red diamonds; Vindigni et al 2009).…”

“…1). High bat activity has also been recorded at these sites, showing that they could also have an important role in bat conservation (Beranek et al 2021; Li et al 2021).…”

Scientific Evidence behind the Ecosystem Services Provided by Sustainable Urban Drainage Systems

“…Oligochaetes, nematodes, ostracods, and chironomids were the most common taxa found [244]. Over time, artificial wetlands stop attracting different species of bats [245,246]. When assessing mosquito risk, they should not be considered collectively, as that does not reveal links with urban wetland habitats or measures of aquatic diversity.…”