The importance of artificial wetlands for birds: A case study from Cyprus

Floating photovoltaic systems homogenize the waterbird communities across subsidence wetlands in the North China Plain

Photovoltaic (PV) power generation provides an environmental-friendly alternative to fossil fuels, but the potential impacts of large-scale PV systems on wildlife have become a hotspot. In the North China Plain, floating photovoltaic (FPV) systems have been extensively installed across subsidence wetlands created by underground coal mining. However, there have been no studies investigating the effects of FPV systems on waterbird communities. During the wintering and migrating seasons of 2016-2017 and 2021-2022, we carried out waterbird surveys in subsidence wetlands with and without FPV systems in the Huainan-Huaibei coal mining area in the North China Plain to examine the effects of FPV systems on waterbird communities. After installation of FPV systems, waterbird numbers increased, but Simpson diversity and Pielou evenness decreased, with no significant changes in species richness. The presence of FPV systems resulted in decrease in the proportion of diving birds but increase in the proportion of vegetation gleaners. The FPV systems leaded to decrease in the proportion of herons in October but increase in other months. Besides the effect of FPV systems, we also found that Simpson diversity and the proportion of ducks increased, while the occurrence rate of shorebirds and gulls decreased from 2016 to 2021. Our results indicate that the cover of FPV systems may homogenize waterbird communities across subsidence wetlands. This study provides the first information on the effects of the FPV systems on waterbirds in artificial wetlands and highlights the need for further research to understand the ecological implications of FPV installations in wetland ecosystems.

Bird Communities and the Rehabilitation of Al Karaana Lagoons in Qatar

Qatar, a peninsular country in the Persian Gulf, is significant to avian species due to its location along the African–Eurasian Flyway, a key migratory path. Receiving untreated domestic and industrial liquid waste from Qatar in the past, Al Karaana Lagoons have since been reconstructed as an artificial wetland to address the growing environmental concern posed by contamination build-up. This study documents the changes in biodiversity at Al Karaana Lagoons following their environmental remediation. Data collected (2015 and 2017) by Ashghal (Public Works Authority) prior to project implementation was analyzed alongside data collected independently following project completion (2019–2021). There was a marked increase in bird biodiversity following remediation, including substantial use by migratory species and resident breeders. Further analysis of water quality data of the TSE (treated sewage effluent) ponds shows that they are eutrophic but still support substantial bird life. The project’s success demonstrates how reclaimed lands can provide important habitats to local and migratory birds and encourages similar restoration efforts in the future in both Qatar and elsewhere. We call for the continued monitoring of the site and the implementation of guidelines for the use of the site that balance human activities and habitat quality.

Preferred Attributes for Sustainable Wetland Management in Mpologoma Catchment, Uganda: A Discrete Choice Experiment

Sustainable wetland management is a focus of many countries worldwide. These mainly use protection as a key policy directive for conservation. However, avoidance directives tend to disenfranchise local populations. Thus, such management is often resisted and rarely effective. Tailoring management strategies to user preferences allows conservation to support community livelihoods for sustainable development. This study employed a discrete choice experiment to determine the wetland management attributes preferred by residents of Mpologoma catchment as a prelude to developing a co-management system. Listed in descending order, attribute preferences were paddy farmers’ schemes, fish farming, education and research, protected wetland area, and recreation and tourism. Respondents’ characteristics influenced their choices. Older adults were more likely to support fish farming. In contrast, existing paddy farmers tended to resist such focuses and an increase in protected wetland area. Additionally, respondents with higher education were opposed to paddy farmers’ schemes, and the preference for education and research was positively influenced by respondents’ income. Respondents were willing to pay between $0.64 and $1.76 per household for each unit improvement in the preferred attribute. Our results underscore the role of DCEs in unlocking individuals’ attribute preferences, whose integration into co-management systems can be important for sustainable wetland conservation.

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

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.

Nestedness theory suggests wetland fragments with large areas and macrophyte diversity benefit waterbirds

Many artificial wetland constructions are currently underway worldwide to compensate for the degradation of natural wetland systems. Researchers face the responsibility of proposing wetland management and species protection strategies to ensure that constructed wetlands positively impact waterbird diversity. Nestedness is a commonly occurring pattern for biotas in fragmented habitats with important implications for conservation; however, only a few studies have focused on seasonal waterbird communities in current artificial wetlands. In this study, we used the nestedness theory for analyzing the annual and seasonal community structures of waterbirds in artificial wetlands at Lake Dianchi (China) to suggest artificial wetland management and waterbird conservation strategies. We carried out three waterbird surveys per month for one year to observe the annual, spring, summer, autumn, and winter waterbird assemblages in 27 lakeside artificial wetland fragments. We used the NeD program to quantify nestedness patterns of waterbirds at the annual and seasonal levels. We also determined Spearman partial correlations to examine the associations of nestedness rank and habitat variables to explore the factors underlying nestedness patterns. We found that annual and all four seasonal waterbird compositions were nested, and selective extinction and habitat nestedness were the main factors governing nestedness. Further, selective colonization was the key driver of nestedness in autumn and winter waterbirds. We suggest that the area of wetland fragments should be as large as possible and that habitat heterogeneity should be maximized to fulfill the conservation needs of different seasonal waterbirds. Furthermore, we suggest that future studies should focus on the least area criterion and that vegetation management of artificial wetland construction should be based on the notion of sustainable development for humans and wildlife.

Spatial ecology of little egret (Egretta garzetta) in Hong Kong uncovers preference for commercial fishponds

Many natural wetlands have been converted to human-influenced wetlands. In some instances, human-influenced wetlands could provide complementary habitats for waterbirds, compensating for the loss of natural wetlands. Inner Deep Bay in Hong Kong is composed of both natural and human-influenced wetlands and is under immense development pressure. From an ecology perspective, we need to understand if different wetland types play the same ecological role. To achieve this, we tracked nine little egrets (Egretta garzetta) using GPS loggers for 14 months to study their spatial ecology, home range, movement and habitat use. We found that over 88% of the home range of all individuals comprised of wetlands (commercial fishponds, mangrove, gei wai, channel, and intertidal mudflat). Among these wetland types, nearly all (seven of nine) individuals preferred commercial fishponds over other habitats in all seasons. Little egrets exhibited seasonal movement and habitat use among seasons, with largest home range, greatest movement, and most frequent visits to commercial fishponds in winter compared to spring and autumn. Our results highlight the significant role of commercial fishponds, providing a feeding ground for little egrets. However, other wetland types cannot be ignored, as they were also used considerably. These findings underscore the importance of maintaining a diversity of wetland types as alternative foraging and breeding habitats.