Dragonfly Conservation in the Increasingly Stressed African Mediterranean-Type Ecosystems

Abstract

Freshwater habitats worldwide are experiencing many threats from environmental and anthropogenic sources, affecting biodiversity and ecosystem functioning. In Africa, particularly in Mediterranean climate zones, rapid human population growth is predicted to have great impact on natural habitats besides naturally occurring events such as unpredictable drought frequency and severity. Here, we analyze the potential correlation between odonate assemblage conservation priority (measured with the Dragonfly Biotic Index: DBI) and the magnitude of climate change and human perturbation in African regions with a dominant Mediterranean climate, namely Northern (NAR: Morocco, Algeria and Tunisia) and Southern African region (SAR: South Africa). Using a compilation of studies assessing odonate assemblages in lotic and lentic habitats of both regions (295 sites in NAR and 151 sites in SAR), we estimated DBI, temporal change in average annual temperature (T), annual precipitation (P), and human footprint index (HFI) in each site, then we tested whether sites with different levels of DBI were associated with different magnitudes of climatic and anthropogenic change. We estimated past (between 1980–1999 and 2000–2018) and future changes (between 1980–1999 and 2081–2100) in T and P based on three CMIP6 scenarios representing low (SSP126), moderate (SSP245), and high emission (SSP585), as well as the change in HFI from 1993 to 2009. We found that assemblages with higher DBI (i.e. higher conservation priority) encountered lower increase in T and slightly greater decrease in P than assemblages with lower DBI (i.e. lower conservation priority) in NAR during 1980–2018, but are projected to experience higher increase in T and lower decrease in P in future projections for 2081–2100. In SAR, the increase in T was mostly similar across assemblages but the decline in P was higher for assemblages with higher DBI during 1980–2018 and 2081–2100, suggesting that assemblages of higher conservation priority in SAR are threatened by drought. While HFI showed an overall increase in NAR but not in SAR, its temporal change showed only minor differences across assemblages with different DBI levels. We discuss the importance of management plans to mitigate the effects of climatic and anthropogenic threats, so improving conservation of odonate assemblages in these regions.

Reproductive phenology of the spider Micrommata ligurina (C.L. Koch, 1845) (Araneae; Sparassidae) across an elevational gradient in Northeast Algeria

“…Some traits varied geographically in ways that are different from what theory predicts. The species is therefore suitable for studies in ecology and evolution, particularly on local adaptation, dispersal, and range dynamics, and especially in Northeast Algeria where climate is projected to become warmer and drier, and expected to impact arthropod communities (Khelifa et al, 2021). We hope that this pioneer study will engage scientists in North Africa in using this interesting biological system in future studies.…”

Sum or mean in calculation of qualitative scoring methods using the Dragonfly Biotic Index, and an alternative approach facilitating conservation prioritization

“…The Dragonfly Biotic Index, an easy-to-use tool for freshwater health assessments, has gained popularity over recent years 5 , 20 , 21 , 23 – 27 , 45 , 46 . Being originally developed for South African species 15 , its use has expanded to other geographical regions 6 , 20 , 22 , 30 , 47 – 49 (see Supplementary Information 1 ).…”

Phenology of the regionally Critically Endangered dragonfly Urothemis edwardsii in the National Park of El Kala, Northeast of Algeria

“…conclusions While U. edwardsii has shown a promising population expansion during the past decade (Khelifa et al, 2016;Baaloudj, 2019), close attention to its status and geographic range dynamics should be paid. Climate change in North Africa is a major threat for the species in the next few decades (Khelifa et al, 2021a), particularly because the species seems to exist in permanent wetlands. The projected decline in precipitation and increase in temperature extremes will likely change the hydroperiod of wetlands and alter the ecological integrity of freshwater ecosystems (Khelifa et al, 2021b;Xi et al, 2021).…”

“…Although they have good dispersal abilities, many species have relict populations that are distant from the core geographic range (Riservato et al, 2009). In Africa, a few examples exist in the North where small populations of dragonflies (Acisoma inflatum Selys, 1882 and Urothemis edwardsii (Selys, 1849)) and damselflies (Pseudagrion sublacteum (Karsch, 1893)) exist far from the core African populations (Khelifa et al, 2021a). Urothemis edwardsii, in particular, is restricted to the northeast of Algeria.…”