Biological invasions are increasingly recognised as a major global change that erodes ecosystems, societal well-being, and economies. However, comprehensive analyses of their economic ramifications are missing for most national economies, despite rapidly escalating costs globally. Türkiye is highly vulnerable to biological invasions owing to its extensive transport network and trade connections as well as its unique transcontinental position at the interface of Europe and Asia. This study presents the first analysis of the reported economic costs caused by biological invasions in Türkiye. The InvaCost database which compiles invasive non-native species' monetary costs was used, complemented with cost searches specific to Türkiye, to describe the spatial and taxonomic attributes of costly invasive non-native species, the types of costs, and their temporal trends. The total economic cost attributed to invasive non-native species in Türkiye (from 202 cost reporting documents) amounted to US$ 4.1 billion from 1960 to 2022. However, cost data were only available for 87 out of 872 (10%) non-native species known for Türkiye. Costs were biased towards a few hyper-costly non-native taxa, such as jellyfish, stink bugs, and locusts. Among impacted sectors, agriculture bore the highest total cost, reaching US$ 2.85 billion, followed by the fishery sector with a total cost of US$ 1.20 billion. Management (i.e., control and eradication) costs were, against expectations, substantially higher than reported damage costs (US$ 2.89 billion vs. US$ 28.4 million). Yearly costs incurred by non-native species rose exponentially over time, reaching US$ 504 million per year in 2020-2022 and are predicted to increase further in the next 10 years. A large deficit of cost records compared to other countries was also shown, suggesting a larger monetary underestimate than is typically observed. These findings underscore the need for improved cost recording as well as preventative management strategies to reduce future post-invasion management costs and help inform decisions to manage the economic burdens posed by invasive non-native species. These insights further emphasise the crucial role of standardised data in accurately estimating the costs associated with invasive non-native species for prioritisation and communication purposes.

Habitats have been undergoing significant changes due to environmental processes and human impact that lead into habitat fragmentation and connectivity loss. To improve quality habitats and maintain ecological connectivity, elements that improve the connectivity of habitats need to be identified. To meet this goal, finding optimal pathways locations plays a key role for designing corridors for biodiversity conservation. Conducted in the Castilla y León region of Spain, this paper aims to determine optimal pathways and to enhance the connectivity of protected areas. To this end, three different scenarios were developed including the Natura 2000 network and their surroundings (Natura 2000, Level 0, and Level 1). We used Restoration Planner (RP) available in GuidosToolbox to analyze the network and detect pairwise optimum restoration pathways between the five largest network objects. Our results demonstrate that connector density varies across the region for each scenario. There was also a large variability in the length of connectors. Connectors were found mainly distributed around the center and northwestern part of Castilla y León. This paper also suggests that proposed new restoration pathways should increase in the study area. Thus, the findings can be used effectively for extensive planning and interpretation in biodiversity conservation.

Frogs have been harvested from the wild for the last 40 years in Turkey. We analysed the population dynamics of Anatolian water frogs (Pelophylax spp.) in the Seyhan and Ceyhan Deltas during 2013–2015. We marked a total of 13,811 individuals during 3 years, estimated population sizes, simulated the dynamics of a harvested population over 50 years, and collated frog harvest and export statistics from the region and for Turkey as a whole. Our capture estimates indicated a population reduction of c. 20% per year, and our population modelling showed that, if overharvesting continues at current rates, the harvested populations will decline rapidly. Simulations with a model of harvested population dynamics resulted in a risk of extinction of > 90% within 50 years, with extinction likely in c. 2032. Our interviews with harvesters revealed their economic dependence on the frog harvest. However, our results also showed that reducing harvest rates would not only ensure the viability of these frog populations but would also provide a source of income that is sustainable in the long term. Our study provides insights into the position of Turkey in the ‘extinction domino’ line, in which harvest pressure shifts among countries as frog populations are depleted and harvest bans are effected. We recommend that harvesting of wild frogs should be banned during the mating season, hunting and exporting of frogs < 30 g should be banned, and harvesters should be trained on species knowledge and awareness of regulations.

The Mediterranean region is one of the 36 hotspots of the world that will be most affected by climate change, with river ecosystems being among the most sensitive to these effects. Therefore, it is necessary to understand and monitor the effects that are occurring through the use of aquatic macroinvertebrates as bioindicators of climate change. To study the use of macroinvertebrates as bioindicators, a systematic literature review was conducted using the PRISMA method. The obtained bibliography was analyzed alongside other known studies to determine the response of these organisms to temperature increases and decreases and alterations in precipitation, as well as their reaction to extreme drought and flood events. The results show that different taxa of macroinvertebrates respond differently to the effects of climate change, always leading to a community alteration with changes in the abundance, richness, phenology, and composition. Therefore, aquatic macroinvertebrates are good bioindicators of the changes caused by climate change, as they respond clearly to the alterations induced by climate change.

Forecasting the distribution patterns of invasive weed species under changing climate conditions is critical for the early identification of especially vulnerable regions and the implementation of effective preventive measures. In this study, the current and potential range of stranglewort (Cynanchum acutum L.)—an invasive alien species (IAS) in certain regions—are predicted under various climate scenarios, using the maximum entropy algorithm. Species occurrence data representing the natural distribution of C. acutum and 15 of the WorldClim bioclimatic variables are used. With an ensemble method, the impact of climate change on the distribution of the species is predicted according to five CMIP6 climate change models and three scenarios (optimistic: SSP245; middle of the road: SSP370; and pessimistic: SSP585). According to the findings, it is predicted in all scenarios that C. acutum could expand its range to the north, particularly in agricultural landscapes. Therefore, the invasive status of this species will likely continue in the future. This emphasizes the need to determine the priority of conservation targets, especially for agricultural areas, to ensure food safety and protect biodiversity.

We examined the seasonal changes in the food composition of the European pond turtle, Emys orbicularis in Lake Sülüklü (Manisa, Turkey) during spring and summer 2010. The stomach contents of 110 (40 ♂♂, 62 ♀♀, eight juveniles) E. orbicularis individuals were analyzed, and 461 prey items were found. Gastropods (2.2%), earthworms (0.4%), insects (67.2%), fishes (6.9%), amphibians (15.0%), and plant material (8.2%) constituted the food of the species. Food consisted primarily of insects and other invertebrates during the breeding season and of vertebrate and plant material (especially seeds and roots) during the post-breeding season. Based on these results, the European pond turtle is a generalist opportunistic omnivore whose diet is most strongly influenced by prey availability.