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European beech (Fagus sylvatica L.) forests have recently experienced severe diebacks that are expected to increase in future. Oriental beech (Fagus sylvatica spp. orientalis (Lipsky) Greut. & Burd) is a potential candidate for assisted migration (AM) in European forests due to its greater genetic diversity and potentially higher drought resistance. Yet AM entails not only benefits, but also risks, and it is therefore important to monitor the progression of introduced (sub)species. Here, we demonstrate the potential of leaf spectroscopy to replace resource-intensive genetic analysis and field phenotyping for the discrimination and characterization of these two beech subspecies. We studied two European beech forests, one in France and one in Switzerland, where Oriental beech from the Greater Caucasus was introduced over 100 years ago. During two summers (2021, 2022), we measured leaf spectral reflectance, leaf morphological and biochemical traits from genotyped adult trees. Subspecies prediction models were developed separately for top-of-canopy leaves (amenable to remote sensing) and bottom-of-canopy leaves (easier to harvest) using partial least squares discriminant analysis (PLS-DA) and different sets of spectral predictors. Morphological, biochemical and spectra-derived leaf traits indicated that Oriental beech trees at the sites studied were characterized by higher lignin and nitrogen per unit leaf area than European beech, suggesting more protein-rich leaves on a per-area basis. The model based on top-of-canopy leaf reflectance spectra in the short-wave-infrared region (SWIR I: 1450–1750 nm) most accurately distinguished Oriental from European beech (BA = 0.86 ± 0.08, k = 0.72 ± 0.15), closely followed by models based on SWIR II, and on spectra-derived traits (BA ≥ 0.84, k ≥ 0.67). This study provides a proof-of-principle for the development of spectroscopy-based approaches when monitoring introduced species, subspecies or provenances. Our findings hold promise for upscaling to large forest areas using airborne remote sensing.

Highlights •We compare the use of PPGIS and Flickr in landscape value assessments. •Landscape values and their spatial patterns are compared across sites. •We find more cross-site differences than similarities both in spatial patterns and value types. •PPGIS elicits a wider spectrum of values, while Flickr mainly elicits relationships to and with landscapes. •We recommend a complementary use in future landscape value studies. Abstract In this study, we bring together participatory mapping and analysis of geolocated social media content from the Flickr platform in an assessment of similarities and differences in their utility for landscape value elicitation. We do so in a Pan-European context comparing types of landscape values and their spatial patterns across 19 case sites in 11 European countries. Across these sites, we find great variety in volume, types and spatial patterns of landscape values elicited from participatory mapping by local people and opportunistic use of tags and image locations crowdsourced from Flickr. Most agreement in spatial patterns across the two data sets are found in densely populated landscapes; however, comparison of types of perceived landscape values is challenged by the differing assumptions of each value elicitation technique. We argue for the complementary potential of both approaches and highlight the strengths and weaknesses of using the two together in landscape research, planning and management. An integrated approach is likely to increase the inclusiveness of landscape value assessments.

Wildlife trade is a multi-billion-dollar sector that impacts a wide range of species, and thus is of significant research and conservation interest. Wildlife trade has also become a prominent topic in the public-facing media, where coverage has intensified following the outbreak of the global COVID-19 pandemic due to the potential connection between wildlife trade and the origin of the SARS Cov2 virus. Given the importance of the media in shaping public understanding and discourse of complex topics such as wildlife trade, this could impact the implementation of and public support for policy decisions. In this study, we followed a standardised protocol to extract wildlife trade-related discussion from 285 professional opinion pieces (NGO reports or articles in conservation-themed forums) and 107 scientific articles published in two time periods: "pre-COVID" (June 1-December 31, 2019) and "during-COVID" (January 1-May 31, 2020). We compared opinion pieces and scientific articles across the two time periods and to each other to investigate potential differences in the presentation of wildlife trade and associated speakers. We found a shift in the way that wildlife trade was discussed in professional opinion pieces between the periods, in that the discussion became less specific in terms of defining the legality and purpose of trade, and the animal groups involved in the "during-COVID" period. The generalised framing of wildlife trade in our dataset also coincided with an increased discussion of highly generalised management strategies, such as blanket bans on wildlife trade. We also found that publications included more quotes from researchers in the "during-COVID" period. In both professional opinion pieces and scientific articles, we found that quotations or research were often from speakers whose affiliation region was different to the geographic range of the trade they were speaking about. This highlights the importance of incorporating local knowledge and considering the diversity of speakers and interviewees in both research and the public-facing media about the wildlife trade.

The island of Mauritius in the Mascarenes has already suffered high levels of extinction, and habitat destruction and invasive alien species have pushed many of the remaining endemic species to the brink of extinction. Round Island, a small island northeast of Mauritius, is home to remnant populations of several reptile species that were once distributed across Mauritius. One of the most threatened of these is Gunther’s gecko Phelsuma guentheri, where despite extensive management efforts, population size remains small and below expectation. We identify determinants of nest-site suitability across Round Island, and examine whether suitable nest sites are a limiting factor for the abundance of P. guentheri. Over one breeding season, we recorded and monitored a high number (269) of nest sites harbouring a total of 1475 eggs. We used the number of eggs at each nest, and the hatching success as proxies for nest-site suitability. To study the reproductive behaviour of P. guentheri, we installed trail cameras at three nest sites. We did not find the expected high frequency of use of hardwood trees as nest sites, as found on Ile aux Aigrettes to the southeast of Mauritius, probably because hardwood trees are still relatively sparse and small on Round Island. Instead, the endemic palm Latania loddigesii was the most used nest sites, harbouring 78.8% of all nests with 56.3% of all eggs. Hatching success was high for palm nest sites (90.6%), rock surfaces (91.8%), and on the endemic screw pine Pandanus vandermeeschii (96%), rates that are similar to that reported from hardwood trees on Ile aux Aigrettes (~90%). Communal nesting occurred on all substrates, with up to five individuals using the same nest site. Egg-laying took place at dusk or at night, lasting around 30 min, whereas hatching occurred mostly during the day, lasting 2–107 min. Females laid eggs every 34 days on average, and produced up to four clutches of 1–2 eggs each within the season. We conclude that P. guentheri does not suffer from nest site limitation on Round Island, and that reproductive success is high in terms of both numbers of eggs laid and hatching success, likely due to ongoing habitat restoration. Further research is needed to investigate the factors inhibiting abundance and distribution of P. guentheri on Round Island.

Short growing seasons, low temperatures, and frequent strong wind classify high mountains as adverse environments, in which pollinator abundance and activity are reduced. In such environments, plants growing in dense stands comprising several species and thus exhibiting larger and more diverse flower displays may profit by attracting more visits from scarce alpine pollinators than do plants that grow alone or in patches only composed of conspecifics. To study whether aggregation of plants increases (facilitation) or decreases (competition) the attraction of pollinators, we measured the rate and numbers with which insects entered experimental plots in the Swiss Alps, and their behaviour at flowers in plots that they entered. The plots contained individuals of the blue-flowering cushion plant Eritrichium nanum, either alone or mixed with white- to yellowish-flowering Saxifraga species. Pollinators were generally rare: in 55% of 236 observation periods, no pollinators were observed. Over 95% of the pollinators were Diptera. The average probability of observing any insect at all was higher in plots that contained some Saxifraga flowers, including mixed plots, than in those containing only E. nanum flowers. However, although insects tended to choose Saxifraga as the first flower visited in mixed plots, in all other regards their visitation of Saxifraga and E. nanum flowers in such plots was statistically indistinguishable. We also detected no effect of floral neighbourhood on the frequencies of potentially geitonogamous visits or of transitions among individual plants of the same or different species. Thus, our study suggests that the presence of Saxifraga may facilitate visitation to E. nanum at larger spatial scales, but gives no evidence for either competition or facilitation at small scales within floral neighbourhoods.