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    Predicting potential global and future distributions of the African armyworm (Spodoptera exempta) using species distribution models

    Zeder, M. A. The domestication of animals. J. Anthropol. Res. 68, 161–190 (2012).Article 

    Google Scholar 
    Zohary, D. & Hopf, M. Domestication of Plants in the Old World: The Origin and Spread of Cultivated Plants in West Asia, Europe and the Nile Valley (Oxford University Press, 2000).
    Google Scholar 
    Epanchin-Niell, R., McAusland, C., Liebhold, A., Mwebaze, P. & Springborn, M. R. Biological invasions and international trade: Managing a moving target. Rev. Environ. Econom. Policy 15, 180–190 (2021).Article 

    Google Scholar 
    Gippet, J. M. & Bertelsmeier, C. Invasiveness is linked to greater commercial success in the global pet trade. Proc. Natl. Acad. Sci. 118, e2016337118 (2021).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    Bertelsmeier, C. Globalization and the anthropogenic spread of invasive social insects. Curr. Opin. Insect Sci. 46, 16–23 (2021).PubMed 
    Article 

    Google Scholar 
    Charles, H. & Dukes, J. S. Biological Invasions 217–237 (Springer, 2008).
    Google Scholar 
    Bellard, C., Cassey, P. & Blackburn, T. M. Alien species as a driver of recent extinctions. Biol. Let. 12, 20150623 (2016).Article 

    Google Scholar 
    Bertolino, S. et al. Spatially explicit models as tools for implementing effective management strategies for invasive alien mammals. Mamm. Rev. 50, 187–199 (2020).Article 

    Google Scholar 
    Grimaldi, D., Engel, M. S., Engel, M. S. & Engel, M. S. Evolution of the Insects (Cambridge University Press, 2005).MATH 

    Google Scholar 
    Hill, M. P., Clusella-Trullas, S., Terblanche, J. S. & Richardson, D. M. Vol. 18, 883–891 (Springer, 2016).Sawicka, B. & Egbuna, C. Natural Remedies for Pest, Disease and Weed Control 1–16 (Elsevier, 2020).Book 

    Google Scholar 
    de la Vega, G. J. & Corley, J. C. Drosophila suzukii (Diptera: Drosophilidae) distribution modelling improves our understanding of pest range limits. Int. J. Pest Manag. 65, 217–227 (2019).Article 

    Google Scholar 
    Kriticos, D. J. et al. The potential distribution of invading Helicoverpa armigera in North America: Is it just a matter of time? PLoS ONE 10, e0119618 (2015).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    Early, R., González-Moreno, P., Murphy, S. T. & Day, R. Forecasting the global extent of invasion of the cereal pest Spodoptera frugiperda, the fall armyworm. NeoBiota 40, 25–50 (2018).Article 

    Google Scholar 
    Day, R. et al. Fall armyworm: Impacts and implications for Africa. Outlooks Pest Manag. 28, 196–201 (2017).Article 

    Google Scholar 
    Rose, D. D. & Page, W. W. The African Armyworm Handbook 304 (Chatham, 2000).
    Google Scholar 
    De Groote, H. et al. Spread and impact of fall armyworm (Spodoptera frugiperda JE Smith) in maize production areas of Kenya. Agric. Ecosyst. Environ. 292, 106804 (2020).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    Cheke, R. & Tucker, M. An evaluation of potential economic returns from the strategic control approach to the management of African armyworm Spodoptera exempta (Lepidoptera: Noctuidae) populations in eastern Africa. Crop Prot. 14, 91–103 (1995).Article 

    Google Scholar 
    Fox, K. Migrant Lepidoptera in New Zealand 1972–1973. N. Z. Entomol. 5, 268–271 (1973).Article 

    Google Scholar 
    Baker, G. An Outbreak of Spodoptera exempta (Walker) (Lepidoptera: Noctuidae) in the Highlands of Papua New Guinea (1978).Haggis, M. J. Distribution, Frequency of Attack and Seasonal Incidence of the African Armyworm Spodoptera exempta (Walk.) (Lep.: Noctuidae), with Particular Reference to Africa and Southwestern Arabia (Tropical Development and Research Institute, 1984).
    Google Scholar 
    Brown, E. Control of the African armyworm, Spodoptera exempta (Walk.)—An appreciation of the problem. East Afr. Agric. For. J. 35, 237–245 (1970).Article 

    Google Scholar 
    Rose, D. & Rainey, R. C. The significance of low-density populations of the African armyworm Spodoptera exempta (Walk.). Philos. Trans. R. Soc. Lond. B Biol. Sci. 287, 393–402 (1979).ADS 
    Article 

    Google Scholar 
    Tucker, M. & Pedgley, D. Rainfall and outbreaks of the African armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae). Bull. Entomol. Res. 73, 195–199 (1983).Article 

    Google Scholar 
    Tucker, M. Forecasting the severity of armyworm seasons in East Africa from early season rainfall. Int. J. Trop. Insect Sci. 5, 51–55 (1984).Article 

    Google Scholar 
    Wilson, K. & Gatehouse, A. Seasonal and geographical variation in the migratory potential of outbreak populations of the African armyworm moth, Spodoptera exempta. J. Anim. Ecol. 62, 169–181 (1993).Article 

    Google Scholar 
    Odiyo, P. O. Development of the first outbreaks of the African armyworm, Spodoptera exempta (Walk.), between Kenya and Tanzania during the ‘off-season’ months of July to December. Int. J. Trop. Insect Sci. 1, 305–318 (1981).Article 

    Google Scholar 
    Haggis, M. Forecasting the severity of seasonal outbreaks of African armyworm, Spodoptera exempta (Lepidoptera: Noctuidae) in Kenya from the previous year’s rainfall. Bull. Entomol. Res. 86, 129–136 (1996).Article 

    Google Scholar 
    Harvey, A. & Mallya, G. Predicting the severity of Spodoptera exempta (Lepidoptera: Noctuidae) outbreak seasons in Tanzania. Bull. Entomol. Res. 85, 479–487 (1995).Article 

    Google Scholar 
    Holt, J., Mushobozi, W., Tucker, M. & Venn, J. Workshop on Research Priorities for Migrant Pests of Agriculture in Southern Africa, 151.Matthew Hill, T. C. M. Bloomberg (Online, 2017).Wilson, K. The Conversation (United Kingdom, 2017).Day, R. K. et al. WormBase: A data management and information system for forecasting Spodoptera exempta (Lepidoptera: Noctuidae) in eastern Africa. J. Econ. Entomol. 89, 1–10 (1996).Article 

    Google Scholar 
    Guisan, A. & Thuiller, W. Predicting species distribution: Offering more than simple habitat models. Ecol. Lett. 8, 993–1009 (2005).PubMed 
    Article 

    Google Scholar 
    Elith, J. & Leathwick, J. R. Species distribution models: Ecological explanation and prediction across space and time. Annu. Rev. Ecol. Evol. Syst. 40, 677–697 (2009).Article 

    Google Scholar 
    Bosso, L. et al. The rise and fall of an alien: Why the successful colonizer Littorina saxatilis failed to invade the Mediterranean Sea. Biol. Invas. https://doi.org/10.1007/s10530-022-02838-y (2022).Article 

    Google Scholar 
    Sutherst, R. W. Pest species distribution modelling: Origins and lessons from history. Biol. Invas. 16, 239–256 (2014).Article 

    Google Scholar 
    Méndez-Vázquez, L. J., Lira-Noriega, A., Lasa-Covarrubias, R. & Cerdeira-Estrada, S. Delineation of site-specific management zones for pest control purposes: Exploring precision agriculture and species distribution modeling approaches. Comput. Electron. Agric. 167, 105101 (2019).Article 

    Google Scholar 
    Raffini, F. et al. From nucleotides to satellite imagery: Approaches to identify and manage the invasive pathogen Xylella fastidiosa and its insect vectors in Europe. Sustainability 12, 4508 (2020).CAS 
    Article 

    Google Scholar 
    Araújo, M. B. et al. Standards for distribution models in biodiversity assessments. Sci. Adv. 5, 4858 (2019).ADS 
    Article 

    Google Scholar 
    Hosmer, D. W. Jr., Lemeshow, S. & Sturdivant, R. X. Applied Logistic Regression Vol. 398 (Wiley, 2013).MATH 
    Book 

    Google Scholar 
    Landis, J. R. & Koch, G. G. The measurement of observer agreement for categorical data. Biometrics 33, 159–174 (1977).CAS 
    PubMed 
    MATH 
    Article 

    Google Scholar 
    Kalisa, W. et al. Assessment of climate impact on vegetation dynamics over East Africa from 1982 to 2015. Sci. Rep. 9, 1–20 (2019).ADS 
    CAS 
    Article 

    Google Scholar 
    Beck, H. E. et al. Present and future Köppen-Geiger climate classification maps at 1-km resolution. Sci. Data 5, 1–12 (2018).ADS 
    Article 

    Google Scholar 
    Mayaux, P., Bartholomé, E., Fritz, S. & Belward, A. A new land-cover map of Africa for the year 2000. J. Biogeogr. 31, 861–877 (2004).Article 

    Google Scholar 
    Marchant, R. et al. Drivers and trajectories of land cover change in East Africa: Human and environmental interactions from 6000 years ago to present. Earth Sci. Rev. 178, 322–378 (2018).ADS 
    Article 

    Google Scholar 
    Elith, J., Kearney, M. & Phillips, S. The art of modelling range-shifting species. Methods Ecol. Evol. 1, 330–342 (2010).Article 

    Google Scholar 
    Pemberton, C. E. Highlights in the history of entomology in Hawaii 1778–1963. Pac. Insects 6, 689–729 (1964).
    Google Scholar 
    Andow, D. A. Vegetational diversity and arthropod population response. Annu. Rev. Entomol. 36, 561–586 (1991).Article 

    Google Scholar 
    Andow, D. The extent of monoculture and its effects on insect pest populations with particular reference to wheat and cotton. Agr. Ecosyst. Environ. 9, 25–35 (1983).Article 

    Google Scholar 
    Oliveira, C., Auad, A., Mendes, S. & Frizzas, M. Crop losses and the economic impact of insect pests on Brazilian agriculture. Crop Prot. 56, 50–54 (2014).Article 

    Google Scholar 
    Furlong, M. J., Wright, D. J. & Dosdall, L. M. Diamondback moth ecology and management: Problems, progress, and prospects. Annu. Rev. Entomol. 58, 517–541 (2013).CAS 
    PubMed 
    Article 

    Google Scholar 
    Howse, M. W., Haywood, J. & Lester, P. J. Bioclimatic modelling identifies suitable habitat for the establishment of the invasive European paper wasp (Hymenoptera: Vespidae) across the southern hemisphere. Insects 11, 784 (2020).PubMed Central 
    Article 

    Google Scholar 
    Rose, D., Dewhurst, C., Page, W. & Fishpool, L. The role of migration in the life system of the African armyworm Spodoptera exempta. Int. J. Trop. Insect Sci. 8, 561–569 (1987).Article 

    Google Scholar 
    Dewhurst, C. F., Page, W. W. & Rose, D. J. The relationship between outbreaks, rainfall and low density populations of the African armyworm, Spodoptera exempta, Kenya. Entomol. Exp. et Appl. 98, 285–294 (2001).Article 

    Google Scholar 
    Aguilon, D. J. & Velasco, L. R. Effects of larval rearing temperature and host plant condition on the development, survival, and coloration of African armyworm, Spodoptera exempta Walker (Lepidoptera: Noctuidae). J. Environ. Sci. Manag. 18, 54 (2015).Article 

    Google Scholar 
    David, W. & Ellaby, S. The viability of the eggs of the African army-worm, Spodoptera exempta in laboratory cultures. Entomol. Exp. Appl. 18, 269–280 (1975).Article 

    Google Scholar 
    He, L., Zhao, S., Ali, A., Ge, S. & Wu, K. Ambient humidity affects development, survival, and reproduction of the invasive fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), China. J. Econ. Entomol. 114, 1145–1158 (2021).PubMed 
    Article 

    Google Scholar 
    Janssen, J. Effects of the mineral composition and water content of intact plants on the fitness of the African armyworm. Oecologia 95, 401–409 (1993).ADS 
    CAS 
    PubMed 
    Article 

    Google Scholar 
    Shahzad, M. S. et al. Modelling population dynamics of army worm (Spodoptera litura F.) (Lepidoptera: Noctuiidae) in relation to meteorological factors in Multan, Punjab, Pakistan. Int. J. Agron. Agric. Res. 5, 39–45 (2014).
    Google Scholar 
    Garcia, A. G., Ferreira, C. P., Godoy, W. A. & Meagher, R. L. A computational model to predict the population dynamics of Spodoptera frugiperda. J. Pest. Sci. 92, 429–441 (2019).Article 

    Google Scholar 
    Hickling, R., Roy, D. B., Hill, J. K., Fox, R. & Thomas, C. D. The distributions of a wide range of taxonomic groups are expanding polewards. Glob. Change Biol. 12, 450–455 (2006).ADS 
    Article 

    Google Scholar 
    Vanhanen, H., Veteli, T. O., Paivinen, S., Kellomaki, S. & Niemela, P. Climate change and range shifts in two insect defoliators: Gypsy moth and nun moth-a model study. Silva Fennica 41, 621 (2007).Article 

    Google Scholar 
    Falk, W. & Hempelmann, N. Species favourability shift in Europe due to climate change: A case study for Fagus sylvatica L. and Picea abies (L.) Karst. based on an ensemble of climate models. J. Climatol. 2013, 1–18 (2013).Article 

    Google Scholar 
    Arora, R. & Dhawan, A. Climate Change and Insect Pest Management. Integrated Pest Management 44–60 (Scientific Publisher, 2013).
    Google Scholar 
    Andrew, N. R. & Hill, S. J. Effect of climate change on insect pest management. In Environmental Pest Management: Challenges for Agronomists, Ecologists, Economists and Policymakers, 197 (2017).De Boer, J. G. & Harvey, J. A. Range-expansion in processionary moths and biological control. Insects 11, 267 (2020).PubMed Central 
    Article 

    Google Scholar 
    Bras, A. et al. A complex invasion story underlies the fast spread of the invasive box tree moth (Cydalima perspectalis) across Europe. J. Pest. Sci. 92, 1187–1202 (2019).Article 

    Google Scholar 
    Araújo, M. B. et al. Heat freezes niche evolution. Ecol. Lett. 16, 1206–1219 (2013).PubMed 
    Article 

    Google Scholar 
    Barford, E. Crop pests advancing with global warming. Nature 10, 13644 (2013).
    Google Scholar 
    Bebber, D. P., Ramotowski, M. A. & Gurr, S. J. Crop pests and pathogens move polewards in a warming world. Nat. Clim. Change 3, 985–988 (2013).ADS 
    Article 

    Google Scholar 
    Rubenstein, D. I. The greenhouse effect and changes in animal behavior: Effects on social structure and life-history strategies. In Global Warming and Biological Diversity, 180–192 (1992).Karuppaiah, V. & Sujayanad, G. Impact of climate change on population dynamics of insect pests. World J. Agric. Sci. 8, 240–246 (2012).
    Google Scholar 
    Jakhar, B. et al. Influence of climate change on Helicoverpa armigera (Hubner) in pigeonpea. J. Agric. Ecol. 2, 25–31 (2016).
    Google Scholar 
    Akbar, S. M., Pavani, T., Nagaraja, T. & Sharma, H. Influence of CO 2 and temperature on metabolism and development of Helicoverpa armigera (Noctuidae: Lepidoptera). Environ. Entomol. 45, 229–236 (2016).CAS 
    PubMed 
    Article 

    Google Scholar 
    Magandana, T. P., Hassen, A. & Tesfamariam, E. H. Seasonal herbaceous structure and biomass production response to rainfall reduction and resting period in the semi-arid grassland area of South Africa. Agronomy 10, 1807 (2020).CAS 
    Article 

    Google Scholar 
    Gherardi, L. A. & Sala, O. E. Enhanced precipitation variability decreases grass-and increases shrub-productivity. Proc. Natl. Acad. Sci. 112, 12735–12740 (2015).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    Scheiter, S. & Higgins, S. I. Impacts of climate change on the vegetation of Africa: An adaptive dynamic vegetation modelling approach. Glob. Change Biol. 15, 2224–2246 (2009).ADS 
    Article 

    Google Scholar 
    Hernandez, P. A., Graham, C. H., Master, L. L. & Albert, D. L. The effect of sample size and species characteristics on performance of different species distribution modeling methods. Ecography 29, 773–785 (2006).Article 

    Google Scholar 
    Jiménez-Valverde, A., Lobo, J. & Hortal, J. The effect of prevalence and its interaction with sample size on the reliability of species distribution models. Community Ecol. 10, 196–205 (2009).Article 

    Google Scholar 
    Renault, D., Laparie, M., McCauley, S. J. & Bonte, D. Environmental adaptations, ecological filtering, and dispersal central to insect invasions. Annu. Rev. Entomol. 63, 345–368 (2018).CAS 
    PubMed 
    Article 

    Google Scholar 
    Ellis, S. New pest response guidelines: Spodoptera. USDA/APHIS/PPQ/PDMP (2004).Waage, J. & Mumford, J. D. Agricultural biosecurity. Philos. Trans. R. Soc. B Biol. Sci. 363, 863–876 (2008).CAS 
    Article 

    Google Scholar 
    Anand, M. A systems approach to agricultural biosecurity. Health Secur. 16, 58–68 (2018).PubMed 
    Article 

    Google Scholar 
    MacLeod, A., Pautasso, M., Jeger, M. J. & Haines-Young, R. Evolution of the international regulation of plant pests and challenges for future plant health. Food Secur. 2, 49–70 (2010).Article 

    Google Scholar 
    Jiménez-Valverde, A. et al. Use of niche models in invasive species risk assessments. Biol. Invas. 13, 2785–2797 (2011).Article 

    Google Scholar 
    Oluwole, F. A., Sambo, J. M. & Sikhalazo, D. Long-term effects of different burning frequencies on the dry savannah grassland in South Africa. Afr. J. Agric. Res. 3, 147–153 (2008).
    Google Scholar 
    Kalleshwaraswamy, C. et al. First Report of the Fall Armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an Alien Invasive Pest on Maize in India (2018).Bentivenha, J., Baldin, E., Hunt, T., Paula-Moraes, S. & Blankenship, E. Intraguild competition of three noctuid maize pests. Environ. Entomol. 45, 999–1008 (2016).CAS 
    PubMed 
    Article 

    Google Scholar 
    Chapman, J. W. et al. Fitness consequences of cannibalism in the fall armyworm, Spodoptera frugiperda. Behav. Ecol. 10, 298–303 (1999).Article 

    Google Scholar 
    Divya, J., Kalleshwaraswamy, C., Mallikarjuna, H. & Deshmukh, S. Does recently invaded fall armyworm, Spodoptera frugiperda displace native lepidopteran pests of maize in India? Curr. Sci. 120, 1358 (2021).Article 

    Google Scholar 
    Hailu, G. et al. Could fall armyworm, Spodoptera frugiperda (JE Smith) invasion in Africa contribute to the displacement of cereal stemborers in maize and sorghum cropping systems. Int. J. Trop. Insect Sci. 41, 1753–1762 (2021).Article 

    Google Scholar 
    Srivastava, V., Lafond, V. & Griess, V. C. Species distribution models (SDM): Applications, benefits and challenges in invasive species management. CAB Rev. 14, 1–13 (2019).Article 

    Google Scholar 
    Fick, S. E. & Hijmans, R. J. WorldClim 2: New 1-km spatial resolution climate surfaces for global land areas. Int. J. Climatol. 37, 4302–4315 (2017).Article 

    Google Scholar 
    Eyring, V. et al. Overview of the coupled model intercomparison project phase 6 (CMIP6) experimental design and organization. Geosci. Model Dev. 9, 1937–1958 (2016).ADS 
    Article 

    Google Scholar 
    Wu, T. et al. The Beijing Climate Center climate system model (BCC-CSM): The main progress from CMIP5 to CMIP6. Geosci. Model Dev. 12, 1573–1600 (2019).ADS 
    Article 

    Google Scholar 
    O’Neill, B. C. et al. The roads ahead: Narratives for shared socioeconomic pathways describing world futures in the 21st century. Glob. Environ. Change 42, 169–180 (2017).Article 

    Google Scholar 
    Petitpierre, B., Broennimann, O., Kueffer, C., Daehler, C. & Guisan, A. Selecting predictors to maximize the transferability of species distribution models: Lessons from cross-continental plant invasions. Glob. Ecol. Biogeogr. 26, 275–287 (2017).Article 

    Google Scholar 
    Cano, J. et al. Modelling the spatial distribution of aquatic insects (Order Hemiptera) potentially involved in the transmission of Mycobacterium ulcerans in Africa. Parasit. Vectors 11, 1–16 (2018).Article 

    Google Scholar 
    Gómez-Undiano, I. Modelos y patrones de distribución geográfica de especies de Culicidae (Culex pipiens, Mansonia africana y Mansonia uniformis) vectores de filariasis linfática en ámbitos urbanos y periurbanos del África subsahariana. Máster en Zoología thesis, Universidad Complutense de Madrid (2018).R: A Language and Environment for Statistical Computing. (R Foundation for Statistical Computing, 2020).Phillips, S. J. et al. Sample selection bias and presence-only distribution models: Implications for background and pseudo-absence data. Ecol. Appl. 19, 181–197 (2009).PubMed 
    Article 

    Google Scholar 
    Elith, J. et al. Novel methods improve prediction of species’ distributions from occurrence data. Ecography 29, 129–151 (2006).Article 

    Google Scholar 
    Barbet-Massin, M., Jiguet, F., Albert, C. H. & Thuiller, W. Selecting pseudo-absences for species distribution models: How, where and how many? Methods Ecol. Evol. 3, 327–338 (2012).Article 

    Google Scholar 
    Thuiller, W., Lafourcade, B., Engler, R. & Araújo, M. B. BIOMOD—A platform for ensemble forecasting of species distributions. Ecography 32, 369–373 (2009).Article 

    Google Scholar 
    Thuiller, W. et al. Package ‘biomod2’. Species Distribution Modeling Within an Ensemble Forecasting Framework (2016).Acevedo, P., Jiménez-Valverde, A., Lobo, J. M. & Real, R. Delimiting the geographical background in species distribution modelling. J. Biogeogr. 39, 1383–1390 (2012).Article 

    Google Scholar 
    VanDerWal, J., Shoo, L. P., Graham, C. & Williams, S. E. Selecting pseudo-absence data for presence-only distribution modeling: How far should you stray from what you know? Ecol. Model. 220, 589–594 (2009).Article 

    Google Scholar 
    Hijmans, R., Phillips, S., Leathwick, J. & Elith, J. (2012).Araújo, M. B. & New, M. Ensemble forecasting of species distributions. Trends Ecol. Evol. 22, 42–47 (2007).PubMed 
    Article 

    Google Scholar 
    Gama, M., Crespo, D., Dolbeth, M. & Anastácio, P. M. Ensemble forecasting of Corbicula fluminea worldwide distribution: Projections of the impact of climate change. Aquat. Conserv. Mar. Freshw. Ecosyst. 27, 675–684 (2017).Article 

    Google Scholar 
    Liu, C., White, M., Newell, G. & Griffioen, P. Species distribution modelling for conservation planning in Victoria, Australia. Ecol. Model. 249, 68–74 (2013).Article 

    Google Scholar  More

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    How a COVID lockdown changed bird behaviour

    Sightings of some common bird species increased during the UK’s 2020 lockdown.Credit: Tolga Akmen/AFP via Getty

    People weren’t the only ones who changed their ways during the COVID-19 pandemic — birds did, too. Four out of five of the most commonly observed birds in the United Kingdom altered their behaviour during the nation’s first lockdown of 2020, although they did so in different ways depending on the species, according to an analysis.The study, published in Proceedings of the Royal Society B on 21 September1, is one of several that used the disruptions brought about by the pandemic — from a reduction in the number of cars on the roads to the closure of some national parks — to quantify the impact that humanity has on the natural world. Although some research has found that lockdowns had a largely positive effect on wildlife2, the latest data from the United Kingdom provide a much more nuanced picture (see Bird Behaviour).

    Credit: Warrington et al/Proceedings of the Royal Society B

    “People didn’t disappear during the lockdown,” says co-author Miyako Warrington, a behavioural ecologist at the University of Manitoba in Winnipeg, Canada. “We changed our behaviour, and wildlife responded.”Rare experimentIn the early months of the pandemic, social media was abuzz with reports of wild animals being seen in unusual places. These claims were partially validated when Warrington and her colleagues reported that, in 2020, many bird species in the United States and Canada were spotted moving into spaces usually occupied by people2.To see how a COVID-19 lockdown affected birds in the United Kingdom, Warrington and her colleagues tallied sightings of the 25 most common birds between March and July 2020 — during the country’s first lockdown — and compared their data set with data from previous years. In total, the study included around 870,000 observations.The team then compared this information to data showing how people split their time between home, essential shops and parks: three places people in the United Kingdom were allowed to be during the lockdown.Because people spent more time at home and in parks than before March 2020, the analysis found that 20 of the 25 bird species examined behaved differently during lockdown. Parks — which were flooded with visitors — saw an an uptick in the numbers of corvids and gulls, whereas smaller birds, such as Eurasian blue tits (Cyanistes caeruleus) and house sparrows (Passer domesticus), were spotted less frequently than in previous years. And because people spent more time at home, the number of avian species that visited domestic gardens also dropped, by around one-quarter, compared with previous years.Other species, including rock pigeons (Columba livia), didn’t react to the lockdown at all. Warrington found this surprising, because pigeons are city dwellers, so she thought they would be affected by the changes in people’s behaviour. “But they don’t give a crap about what we do,” she says.Adapting to changeThe birds that altered their habits during the lockdown were probably responding to changes in human behaviour, says Warrington. Tits and other birds whose numbers dipped might have fled when people and their pets started spending more time in parks and gardens. The reverse could be true for scavengers, such as gulls and corvids, which might have benefited from park visitors leaving behind rubbish for them to feed on.When combined with the results of other studies, the behaviour of British birds reveals the complex ways in which wildlife was affected by lockdowns and underlines the importance of reducing the disturbance of animals by people, says Raoul Manenti, a conservation zoologist at the University of Milan in Italy.For Warrington, that means acknowledging that lockdowns were not universally good for wildlife. “Our relationship with nature is complicated,” she says. By developing a better understanding of this relationship, “we know we can affect positive change as long as we do it in a thoughtful manner”. More

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    Identifying driving factors of urban land expansion using Google Earth Engine and machine-learning approaches in Mentougou District, China

    Orr, D. W. Land use and climate change. Conserv. Biol. 22(6), 1372–1374 (2010).
    Google Scholar 
    Zhang, X. D. et al. Tropospheric ozone perturbations induced by urban land expansion in China from 1980 to 2017. Environ. Sci. Technol. https://doi.org/10.1021/ACS.EST.1C06664 (2022).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    Noojipady, P. et al. Forest carbon emissions from cropland expansion in the Brazilian cerrado biome. Environ. Res. Lett. 12(2), 025004. https://doi.org/10.1088/1748-9326/aa5986 (2017).ADS 
    CAS 
    Article 

    Google Scholar 
    Zhu, B., Xun, Z., Ran, Z. & Zhao, X. Study of multiple land use planning based on the coordinated development of wetland farmland: A case study of Fuyuan City, China. Sustainability 11(1), 271. https://doi.org/10.3390/su11010271 (2019).Article 

    Google Scholar 
    Tong, D., Chu, J., Han, Q. & Liu, X. How land finance drives urban expansion under fiscal pressure: Evidence from Chinese cities. Land. 11(2), 253. https://doi.org/10.3390/land11020253 (2022).Article 

    Google Scholar 
    Chen, J., Chang, K. T., Karacsonyi, D. & Zhang, X. Comparing urban land expansion and its driving factors in Shenzhen and Dongguan, China. Habitat. Int. 43, 61–71. https://doi.org/10.1016/j.habitatint.2014.01.004 (2014).CAS 
    Article 

    Google Scholar 
    Shu, B. R., Zhang, H. H., Li, Y. L., Qu, Y. & Chen, L. Spatiotemporal variation analysis of driving forces of urban land spatial expansion using logistic regression: A case study of port towns in Taicang City, China. Habitat. Int. 43, 181–190. https://doi.org/10.1016/j.habitatint.2014.02.004 (2014).Article 

    Google Scholar 
    Wang, R. Y., He, W. S., Wu, D., Zhang, L. & Li, Y. J. Urban Land expansion simulation considering the diffusional and aggregated growth simultaneously: A case study of Luoyang City. Sustainability. 13(17), 9781–9781. https://doi.org/10.3390/su13179781 (2021).Article 

    Google Scholar 
    Wei, Y. D. & Ye, X. Determinants of urban land expansion and environmental change in China. Stoch. Env. Res. Risk. A. 28(4), 757–765. https://doi.org/10.1007/s00477-013-0840-9 (2014).Article 

    Google Scholar 
    Yang, Q. K., Duan, X. J., Yang, L. & Wang, L. Spatial-Temporal patterns and driving factors of rapid urban land development in provincial China: A case study of Jiangsu. Sustainability. 9(12), 2371. https://doi.org/10.3390/su9122371 (2017).Article 

    Google Scholar 
    Zhong, Y., Lin, A. & Zhou, Z. Evolution of the pattern of spatial expansion of urban land use in the Poyang Lake ecological economic zone. Int. J. Environ. Res. Public. Health. 16(1), 117. https://doi.org/10.3390/ijerph16010117 (2019).Article 
    PubMed Central 

    Google Scholar 
    Wu, C., Huang, X. & Chen, B. Telecoupling mechanism of urban land expansion based on transportation accessibility: A case study of transitional Yangtze River economic Belt, China. Land Use Policy 96, 104687. https://doi.org/10.1016/j.landusepol.2020.104687 (2020).Article 

    Google Scholar 
    Zhao, P. Sustainable urban expansion and transportation in a growing megacity: Consequences of urban sprawl for mobility on the urban fringe of Beijing. Habitat. Int. 34(2), 236–243. https://doi.org/10.1016/j.habitatint.2009.09.008 (2010).Article 

    Google Scholar 
    Cai, W. J. & Tu, F. Y. Spatiotemporal characteristics and driving forces of construction land expansion in Yangtze River economic belt, China. PLoS ONE 15(1), 0227299. https://doi.org/10.1371/journal.pone.0227299 (2020).CAS 
    Article 

    Google Scholar 
    Salvati, L., Carlucci, M., Grigoriadis, E. & Chelli, F. M. Uneven dispersion or adaptive polycentrism? Urban expansion, population dynamics and employment growth in an “ordinary” city. Rev. Region. Res. 38(1), 1–25. https://doi.org/10.1007/s10037-017-0115-x (2017).Article 

    Google Scholar 
    Cao, Y., Ba, I. Z., Zhou, W. & Zhang, X. Analyses of traits and driving forces on urban land expansion in a typical coal-resource-based city in a loess area. Environ. Earth. Sci. 75(16), 1191.1-11911.3. https://doi.org/10.1007/s12665-016-5926-5 (2016).Article 

    Google Scholar 
    Davies, R. G., Barbosa, O. D. & Fuller, R. A. City-wide relationships between green spaces, urban land use and topography. Urban Ecosyst. 11(3), 269. https://doi.org/10.1007/s11252-008-0062-y (2008).Article 

    Google Scholar 
    Cheng, L. L., Liu, M. & Zhan, J. Q. Land use scenario simulation of mountainous districts based on Dinamica EGO model. J. Mt. Sci. 17(2), 289–303. https://doi.org/10.1007/s11629-019-5491-y (2020).Article 

    Google Scholar 
    Liu, J. Y., Zhan, J. Y. & Deng, X. Z. Spatio-temporal patterns and driving forces of urban land expansion in China during the economic reform era. Ambio 34, 450–455. https://doi.org/10.1579/0044-7447-34.6.450 (2005).Article 
    PubMed 

    Google Scholar 
    Li, X. M., Zhou, W. & Quyang, Z. J. Forty years of urban expansion in Beijing: What is the relative importance of physical, socioeconomic, and neighborhood factors?. Appl. Geogr. 38, 1–10. https://doi.org/10.1016/j.apgeog.2012.11.004 (2013).Article 

    Google Scholar 
    Wang, Z. W. & Lu, C. H. Urban land expansion and its driving factors of mountain cities in China during 1990–2015. J. Geogr. Sci. 28(8), 1152–1166. https://doi.org/10.1007/s11442-018-1547-0 (2018).MathSciNet 
    Article 

    Google Scholar 
    Zhang, Y. W. & Xie, H. L. Interactive relationship among urban expansion, economic development, and population growth since the reform and opening up in China: An analysis based on a vector error correction model. Land 8(10), 153–153. https://doi.org/10.3390/land8100153 (2019).CAS 
    Article 

    Google Scholar 
    Deng, X., Huang, J., Rozelle, S. & Uchid, E. Growth, population and industrialization, and urban land expansion of China. J. Urban. Econ. 63(1), 96–115. https://doi.org/10.1016/j.jue.2006.12.006 (2006).Article 

    Google Scholar 
    Luo, J., Zhang, X. & Wu, Y. Urban land expansion and the floating population in China: For production or for living?. Cities 74(4), 219–228. https://doi.org/10.1016/j.cities.2017.12.007 (2018).Article 

    Google Scholar 
    Salem, M., Tsurusaki, N. & Divigalpitiya, P. Analyzing the driving factors causing urban expansion in the peri-urban areas using logistic regression: A case study of the greater Cairo region. Infrastructures 4(1), 4. https://doi.org/10.3390/infrastructures4010004 (2019).Article 

    Google Scholar 
    Salem, M., Bose, A. & Chowdhury, I. R. Urban expansion simulation based on various driving factors using a logistic regression model: Delhi as a case study. Sustainability 13(19), 1–17. https://doi.org/10.3390/su131910805 (2021).Article 

    Google Scholar 
    Su, Z. W. et al. Using GIS and Random Forests to identify fire drivers in a forest city, Yichun, China. Geomat. Nat. Hazards. Risk. 9(1), 1207–1229. https://doi.org/10.1080/19475705.2018.1505667 (2018).Article 

    Google Scholar 
    Hu, Y. & Hu, Y. Land cover changes and their driving mechanisms in central Asia from 2001 to 2017 supported by google earth engine. Remote. Sens-Basel. 11(5), 554. https://doi.org/10.3390/rs11050554 (2019).ADS 
    Article 

    Google Scholar 
    Liu, Y., Song, W. & Deng, X. Understanding the spatiotemporal variation of urban land expansion in oasis cities by integrating remote sensing and multi-dimensional dpsir-based indicators. Ecol. Indic. 2(96), 23–37. https://doi.org/10.1016/j.ecolind.2018.01.029 (2019).CAS 
    Article 

    Google Scholar 
    Tian, C., Cheng, L. L., Wang, Y. F., Sun, H. Y. & Yin, T. T. Comprehensive effectiveness evaluation and obstacle diagnosis of mining villages in the transition period. Trans. CSAE. 38(5), 241–249. https://doi.org/10.11975/j.issn.1002-6819.2022.05.029 (2022).Article 

    Google Scholar 
    Cheng, L. L., Sun, H. Y., Zhang, Y. & Zhen, S. Spatial structure optimization of mountainous abandoned mine land reuse based on system dynamics model and CLUE-S model. Int. J. Coal. Sci. Techn. 6, 113–126. https://doi.org/10.1007/s40789-019-0241-x (2019).CAS 
    Article 

    Google Scholar 
    Tian, C., Cheng, L. L. & Yin, T. T. Impacts of anthropogenic and biophysical factors on ecological land using logistic regression and random forest: A case study in Mentougou District, Beijing, China. J. Mt. Sci. 19, 433–445. https://doi.org/10.1007/s11629-021-7022-x (2022).Article 

    Google Scholar 
    Gorelick, N., Hanchr, M., Dixon, M., Ilyushchenko, S. & Moore, R. Google earth engine: Planetary-scale geospatial analysis for everyone. Remote. Sens. Environ. 202, 18–27. https://doi.org/10.1016/j.rse.2017.06.031 (2017).ADS 
    Article 

    Google Scholar 
    Feng, R. D., Wang, F. Y. & Wang, K. Y. Quantifying influences of anthropogenic-natural factors on ecological land evolution in mega-urban agglomeration: A case study of Guangdong-Hong Kong-Macao Greater Bay area. J. Clean. Prod. 283(9), 125304. https://doi.org/10.1016/j.jclepro.2020.125304 (2021).Article 

    Google Scholar 
    Sun, X., Lu, Z., Li, F. & Crittenden, J. C. Analyzing spatio-temporal changes and tradeoffs to support the supply of multiple ecosystem services in Beijing, China. Ecol. Indicat. 94, 117–129. https://doi.org/10.1016/j.ecolind.2018.06.049 (2018).Article 

    Google Scholar 
    Oliveira, S., Oehler, F., San-Miguel-Ayanz, J., Camia, A. & Pereira, J. Modeling spatial patterns of fire occurrence in Mediterranean Europe using multiple regression and random forest. Forest. Ecol. Manag. 275, 117–129. https://doi.org/10.1016/j.foreco.2012.03.003 (2012).Article 

    Google Scholar 
    Ugur, A. Dynamic land cover mapping of urbanized cities with Landsat 8 multi-temporal images: Comparative evaluation of classification algorithms and dimension reduction methods. Isprs Int. J. Geo-Inf. 8(3), 139. https://doi.org/10.3390/ijgi8030139 (2019).Article 

    Google Scholar 
    Chapelle, O. Training a support vector machine in the primal. Neural. Comput. 19(5), 1155. https://doi.org/10.1162/neco.2007.19.5.1155 (2007).MathSciNet 
    Article 
    PubMed 
    MATH 

    Google Scholar 
    Lin, Q. Y., Guo, J. Y., Yan, J. F. & Wang, H. Land use and landscape pattern changes of Weihai, China based on object-oriented SVM classification from Landsat MSS/TM/OLI images. Eur. J. Remote. Sens. 51(1), 1036–1048. https://doi.org/10.1080/22797254.2018.1534532 (2018).Article 

    Google Scholar 
    Devos, O., Ruckebusch, C., Duponchel, L. & Huvenne, J. P. Support vector machines (SVM) in near infrared (NIR) spectroscopy: Focus on parameters optimization and model interpretation. Chemometr. Intell. Lab. 96(1), 27–33. https://doi.org/10.1016/j.chemolab.2008.11.005 (2009).CAS 
    Article 

    Google Scholar 
    Heumann, B. W. An object-based classification of mangroves using a hybrid decision tree-support vector machine approach. Remote. Sens-Basel. 3(11), 2440–2460. https://doi.org/10.3390/rs3112440 (2011).ADS 
    Article 

    Google Scholar 
    Hsu, C., Chang, C. C. & Lin, C. J. A practical guide to support vector classification, 15. Department of Computer Science, National Taiwan University. https://doi.org/10.1111/j.1365-3016.1995.tb00168.x (2009).Aspinall, R. Modelling land use change with generalized linear models-a multi-model analysis of change between 1860 and 2000 in Gallatin valley, Montana. J. Environ. Manage. 72(1–2), 91–103. https://doi.org/10.1016/j.jenvman.2004.02.009 (2004).Article 
    PubMed 

    Google Scholar 
    Wu, W. & Zhang, J. Comparison of spatial and non-spatial logistic regression models for modeling the occurrence of cloud cover in north-eastern Puerto Rico. Appl. Geogr. 37, 52–62. https://doi.org/10.1016/j.apgeog.2012.10.012 (2013).Article 

    Google Scholar 
    Thomas, D. R., Zhu, P. C. & Decady, Y. J. Point estimates and confidence intervals for variable importance in multiple linear regression. J. Educ. Behav. Stat. 32(1), 61–91. https://doi.org/10.1002/bimj.201100134 (2007).Article 

    Google Scholar 
    Huang, B. & Boutros, P. C. The parameter sensitivity of random forests. BMC Bioinform. 17, 331. https://doi.org/10.1186/s12859-016-1228-x (2016).Article 

    Google Scholar 
    Pang, J., Chen, Y., He, S., Qiu, H. & Mao, L. Classification of friction and wear state of wind turbine gearboxes using decision tree and random forest algorithms. J. Tribol-T. Asme. 143(9), 1–28. https://doi.org/10.1115/1.4049257 (2020).CAS 
    Article 

    Google Scholar 
    Liu, M., Hu, S., Ge, Y., Heuvelink, G. & Huang, X. Using multiple linear regression and random forests to identify spatial poverty determinants in rural China. Spat. Stat.-Neth. 42, 100461. https://doi.org/10.1016/j.spasta.2020.100461 (2020).MathSciNet 
    Article 

    Google Scholar 
    Jutidamrongphan, W. Determine the land-use land-cover changes, urban expansion and their driving factors for sustainable development in Gazipur Bangladesh. Atmosphere 12(10), 1353. https://doi.org/10.3390/atmos12101353 (2021).ADS 
    Article 

    Google Scholar 
    Liu, M. & Tian, H. China’s land cover and land use change from 1700 to 2005: estimations from high-resolution satellite data and historical archives. Glob. Biogeochem. Cycles https://doi.org/10.1029/2009GB003687 (2010).Article 

    Google Scholar 
    Tong, Z., Yao, S., Hu, W. & Cui, F. Simulation of urban expansion in Guangzhou Foshan metropolitan area under the influence of accessibility. Scientia. Geographica. Sinica. 38(5), 737–746 (2018).
    Google Scholar 
    Poelmans, L. & Rompaey, A. V. Complexity and performance of urban expansion models. Comput. Environ. Urban Syst. 34(1), 17–27. https://doi.org/10.1016/j.compenvurbsys.2009.06.001 (2010).Article 

    Google Scholar 
    Galinato, S. P. & Gregma, I. The effects of government spending on deforestation due to agricultural land expansion and CO2 related emissions. Ecol. Econ. 122, 43–53. https://doi.org/10.1016/j.ecolecon.2015.10.025 (2016).Article 

    Google Scholar 
    Xie, X. F., Wu, T., Zhu, M., Jiang, G. J. & Xw, E. Comparison of random forest and multiple linear regression models for estimation of soil extracellular enzyme activities in agricultural reclaimed coastal saline land. Ecol. Indic. 120, 106925. https://doi.org/10.1016/j.ecolind.2020.106925 (2021).CAS 
    Article 

    Google Scholar 
    Miller, M. D. The mpacts of Atlanta’s urban sprawl on forest cover and fragmentation. Appl. Geogr. 34, 171–179. https://doi.org/10.1016/j.apgeog.2011.11.010 (2012).ADS 
    Article 

    Google Scholar 
    Güneralp, B. & Seto, K. C. Futures of global urban expansion: uncertainties and implications for biodiversity conservation. Environ. Res. Lett. https://doi.org/10.1088/1748-9326/8/1/014025 (2013).Article 

    Google Scholar 
    Qiao, W. et al. Multi-dimensional expansion of urban space through the lens of land use: The case study of Nanjing city, China. J. Geogr. Sci. 29(5), 749–761. https://doi.org/10.1007/s11442-019-1625-y (2019).Article 

    Google Scholar 
    Yza, B., Lt, A. & Hw, A. An improved approach for monitoring urban built-up areas by combining NPP-VIIRS nighttime light, NDVI, NDWI, and NDBI. J. Clean. Prod. 329, 129488. https://doi.org/10.1016/j.jclepro.2021.129488 (2021).Article 

    Google Scholar  More

  • in

    Honey bees save energy in honey processing by dehydrating nectar before returning to the nest

    Berenbaum, M. R. & Calla, B. Honey as a functional food for Apis mellifera. Annu. Rev. Entomol. 66, 185–208. https://doi.org/10.1146/annurev-ento-040320-074933 (2021).CAS 
    Article 
    PubMed 

    Google Scholar 
    Crane, E. Honey: A Comprehensive Survey (Heinemann, 1975).
    Google Scholar 
    Park, O. W. The storing and ripening of honey by honeybees. J. Econ. Entomol. 18, 405–410 (1925).Article 

    Google Scholar 
    Reinhardt, J. F. Ventilating the bee colony to facilitate the honey ripening process. J. Econ. Entomol. 32, 654–660. https://doi.org/10.1093/jee/32.5.654 (1939).Article 

    Google Scholar 
    Eyer, M., Neumann, P. & Dietemann, V. A look into the cell: Honey storage in honey bees, Apis mellifera. PLoS ONE 11(8), e0161059 (2016).Article 

    Google Scholar 
    Oertel, E., Fieger, E. A., Williams, V. R. & Andrews, E. A. Inversion of cane sugar in the honey stomach of the bee. J. Econ. Entomol. 44, 487–492 (1951).CAS 
    Article 

    Google Scholar 
    Park, O. W. Studies on the changes in nectar concentration produced by the honeybee, Apis mellifera. Part I. Changes which occur between the flower and the hive. Res. Bull. Iowa Agric. Exp. Station 151, 211–243 (1932).
    Google Scholar 
    Nicolson, S. W. & Human, H. Bees get a head start on honey production. Biol. Let. 4, 299–301. https://doi.org/10.1098/rsbl.2008.0034 (2008).Article 

    Google Scholar 
    Nicolson, S. W. & Louw, G. N. Simultaneous measurement of evaporative water loss, oxygen consumption, and thoracic temperature during flight in a carpenter bee. J. Exp. Zool. 222, 287–296 (1982).Article 

    Google Scholar 
    Schmid-Hempel, P., Kacelnik, A. & Houston, A. I. Honeybees maximize efficiency by not filling their crop. Behav. Ecol. Sociobiol. 17, 61–66 (1985).Article 

    Google Scholar 
    Kacelnik, A., Houston, A. I. & Schmid-Hempel, P. Central-place foraging in honey bees: The effect of travel time and nectar flow on crop filling. Behav. Ecol. Sociobiol. 19, 19–24. https://doi.org/10.1007/BF00303838 (1986).Article 

    Google Scholar 
    Wolf, T. J., Schmid-Hempel, P., Ellington, C. P. & Stevenson, R. D. Physiological correlates of foraging efforts in honey-bees: Oxygen consumption and nectar load. Funct. Ecol. 3, 417–424 (1989).Article 

    Google Scholar 
    Mitchell, D. Thermal efficiency extends distance and variety for honeybee foragers: Analysis of the energetics of nectar collection and desiccation by Apis mellifera. J. R. Soc. Interface 16, 20180879. https://doi.org/10.1098/rsif.2018.0879 (2019).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    Corbet, S. A. et al. Native or exotic? Double or single? Evaluating plants for pollinator-friendly gardens. Ann. Bot. 87, 219–232 (2001).Article 

    Google Scholar 
    Harano, K. & Nakamura, J. Nectar loads as fuel for collecting nectar and pollen in honeybees: Adjustment by sugar concentration. J. Comp. Physiol. A. https://doi.org/10.1007/s00359-016-1088-x (2016).Article 

    Google Scholar 
    Nicolson, S. W. & van Wyk, B.-E. Nectar sugars in Proteaceae: Patterns and processes. Aust. J. Bot. 46, 489–504 (1998).Article 

    Google Scholar 
    Corbet, S. A. Nectar sugar content: Estimating standing crop and secretion rate in the field. Apidologie 34, 1–10. https://doi.org/10.1051/apido:2002049 (2003).CAS 
    Article 

    Google Scholar 
    Southwick, E. E. & Pimentel, D. Energy efficiency of honey production by bees. Bioscience 31, 730–732. https://doi.org/10.2307/1308779 (1981).Article 

    Google Scholar 
    Mitchell, D. Nectar, humidity, honey bees (Apis mellifera) and varroa in summer: A theoretical thermofluid analysis of the fate of water vapour from honey ripening and its implications on the control of Varroa destructor. J. R. Soc. Interface 16, 20190048. https://doi.org/10.1098/rsif.2019.0048 (2019).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    Human, H., Nicolson, S. W. & Dietemann, V. Do honeybees, Apis mellifera scutellata, regulate humidity in their nest?. Naturwissenschaften 93, 397–401 (2006).ADS 
    CAS 
    Article 

    Google Scholar 
    Ellis, M. B. Homeostasis: Humidity and water relations in honeybee colonies, MSc thesis, University of Pretoria (2008).Ellis, M., Nicolson, S., Crewe, R. & Dietemann, V. Hygropreference and brood care in the honeybee (Apis mellifera). J. Insect Physiol. 54, 1516–1521. https://doi.org/10.1016/j.jinsphys.2008.08.011 (2008).CAS 
    Article 
    PubMed 

    Google Scholar 
    Portman, Z. M., Ascher, J. S. & Cariveau, D. P. Nectar concentrating behavior by bees (Hymenoptera: Anthophila). Apidologie 52, 1169–1194. https://doi.org/10.1007/s13592-021-00895-1 (2021).Article 

    Google Scholar 
    Nicolson, S. W. Water homeostasis in bees, with the emphasis on sociality. J. Exp. Biol. 212, 429–434. https://doi.org/10.1242/jeb.022343 (2009).Article 
    PubMed 

    Google Scholar 
    Pokorny, T., Lunau, K. & Eltz, T. Raising the sugar content – orchid bees overcome the constraints of suction feeding through manipulation of nectar and pollen provisions. PLoS ONE 9(11), e113823. https://doi.org/10.1371/journal.pone.0113823 (2014).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    Lindauer, M. The water economy and temperature regulation of the honeybee colony. Bee World 36, 81–92 (1955).Article 

    Google Scholar 
    Heinrich, B. Mechanisms of body-temperature regulation in honeybees, Apis mellifera. I. Regulation of head temperature. J. Exp. Biol. 85, 61–72 (1980).Article 

    Google Scholar 
    Cooper, P. D., Schaffer, W. M. & Buchmann, S. L. Temperature regulation of honeybees (Apis mellifera) foraging in the Sonoran desert. J. Exp. Biol. 114, 1–15 (1985).Article 

    Google Scholar 
    Louw, G. N. & Hadley, N. F. Water economy of the honeybee: A stoichiometric accounting. J. Exp. Zool. 235, 147–150 (1985).Article 

    Google Scholar 
    Rodney, S. & Purdy, J. Dietary requirements of individual nectar foragers, and colony-level pollen and nectar consumption: A review to support pesticide exposure assessment for honey bees. Apidologie 51, 163–179. https://doi.org/10.1007/s13592-019-00694-9 (2020).Article 

    Google Scholar 
    Drezner-Levy, T., Smith, B. & Shafir, S. The effect of foraging specialization on various learning tasks in the honey bee (Apis mellifera). Behav. Ecol. Sociobiol. 64, 135–148. https://doi.org/10.1007/s00265-009-0829-z (2009).Article 

    Google Scholar 
    Afik, O. & Shafir, S. Effect of ambient temperature on crop loading in the honey bee, Apis mellifera (Hymenoptera: Apidae). Entomologia Generalis 29, 135–148 (2007).Article 

    Google Scholar 
    Seeley, T. D. Honey bee foragers as sensory units of their colonies. Behav. Ecol. Sociobiol. 34, 51–62 (1994).Article 

    Google Scholar 
    Waller, G. D. Evaluating responses of honeybees to sugar solutions using an artificial-flower feeder. Ann. Entomol. Soc. Am. 65, 857–862 (1972).CAS 
    Article 

    Google Scholar 
    Nicolson, S. W., de Veer, L., Köhler, A. & Pirk, C. W. W. Honeybees prefer warmer nectar and less viscous nectar, regardless of sugar concentration. Proc. R. Soc. B: Biol. Sci. 280, 20131597. https://doi.org/10.1098/rspb.2013.1597 (2013).Article 

    Google Scholar 
    Neff, J. L. & Simpson, B. B. The roles of phenology and reward structure in the pollination biology of wild sunflower (Helianthus annuus L., Asteraceae). Israel J. Bot. 39, 197–216 (1990).
    Google Scholar 
    Waller, G. D., Carpenter, E. W. & Ziehl, O. A. Potassium in onion nectar and its probable effect on attractiveness of onion flowers to honey bees. J. Am. Soc. Hortic. Sci. 97, 535–539 (1972).CAS 
    Article 

    Google Scholar 
    Roubik, D. W., Yanega, D., Aluja, M., Buchmann, S. L. & Inouye, D. W. On optimal nectar foraging by some tropical bees (Hymenoptera: Apidae). Apidologie 26, 197–211 (1995).Article 

    Google Scholar 
    Power, E. F., Stabler, D., Borland, A. M., Barnes, J. & Wright, G. A. Analysis of nectar from low-volume flowers: A comparison of collection methods for free amino acids. Methods Ecol. Evol. 9, 734–743. https://doi.org/10.1111/2041-210X.12928 (2018).Article 
    PubMed 

    Google Scholar 
    Pattrick, J. G., Symington, H. A., Federle, W. & Glover, B. J. The mechanics of nectar offloading in the bumblebee Bombus terrestris and implications for optimal concentrations during nectar foraging. J. R. Soc. Interface 17, 20190632. https://doi.org/10.1098/rsif.2019.0632 (2020).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    Strauss, U., Dietemann, V., Human, H., Crewe, R. M. & Pirk, C. W. W. Resistance rather than tolerance explains survival of savannah honeybees (Apis mellifera scutellata) to infestation by the parasitic mite Varroa destructor. Parasitology 143, 374–387. https://doi.org/10.1017/s0031182015001754 (2016).Article 
    PubMed 

    Google Scholar 
    Dyer, F. C. & Seeley, T. D. Interspecific comparisons of endothermy in honey-bees (Apis): Deviations from the expected size-related patterns. J. Exp. Biol. 127, 1–26. https://doi.org/10.1242/jeb.127.1.1 (1987).Article 

    Google Scholar  More

  • in

    Decomposition stages as a clue for estimating the post-mortem interval in carcasses and providing accurate bird collision rates

    Barrientos, R. et al. A review of searcher efficiency and carcass persistence in infrastructure-driven mortality assessment studies. Biol. Conserv. 222, 146–153 (2018).
    Google Scholar 
    Stevens, B. S., Reese, K. P. & Connelly, J. W. Survival and detectability bias of avian fence collision surveys in sagebrush steppe. J. Wildl. Manag. 75, 437–449 (2011).
    Google Scholar 
    Hunting, K. A Roadmap for PIER Research on Avian Collisions with Power Lines in California. (2002).Barrientos, R. et al. Wire marking results in a small but significant reduction in avian mortality at power lines: A baci designed study. PLoS ONE 7, e32569 (2012).ADS 
    CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Costantini, D., Gustin, M., Ferrarini, A. & Dell’Omo, G. Estimates of avian collision with power lines and carcass disappearance across differing environments. Anim. Conserv. 20, 173–181 (2017).
    Google Scholar 
    Jenkins, A. R. et al. Estimating the impacts of power line collisions on Ludwig’s Bustards Neotis ludwigii. Bird Conserv. Int. 21, 303–310 (2011).
    Google Scholar 
    Shaw, J. M., Reid, T. A., Schutgens, M., Jenkins, A. R. & Ryan, P. G. High power line collision mortality of threatened bustards at a regional scale in the Karoo, South Africa. Ibis (Lond. 1859) 1859(160), 431–446 (2018).
    Google Scholar 
    Gómez-Catasús, J. et al. Factors affecting differential underestimates of bird collision fatalities at electric lines: a case study in the Canary Islands. Ardeola 68, 71–94 (2021).
    Google Scholar 
    Ponce, C., Alonso, J. C., Argandoña, G., García Fernández, A. & Carrasco, M. Carcass removal by scavengers and search accuracy affect bird mortality estimates at power lines. Anim. Conserv. 13, 603–612 (2010).
    Google Scholar 
    Bernardino, J. et al. Bird collisions with power lines: State of the art and priority areas for research. Biol. Conserv. 222, 1–13 (2018).
    Google Scholar 
    Brooks, J. W. & Sutton, L. in Veterinary Forensic Pathology (ed. Brooks, J. W.) 43–63 (2018). https://doi.org/10.1007/978-3-319-67172-7_4Brooks, J. W. Postmortem changes in animal carcasses and estimation of the postmortem interval. Vet. Pathol. 53, 929–940 (2016).CAS 
    PubMed 

    Google Scholar 
    Ascensão, F. et al. Beware that the lack of wildlife mortality records can mask a serious impact of linear infrastructures. Glob. Ecol. Conserv. 19, e00661 (2019).
    Google Scholar 
    Hau, T. C., Hamzah, N. H., Lian, H. H. & Amir Hamzah, S. P. A. Decomposition process and post mortem changes: Review. Sains Malaysiana 43, 1873–1882 (2014).
    Google Scholar 
    Cooper, J. E. in Wildlife Forensic Investigation: Principles and Practice (eds. Cooper, J. & Cooper, M.) 237–324 (CRC Press, 2013). https://doi.org/10.1201/b14553Sutherland, A., Myburgh, J., Steyn, M. & Becker, P. J. The effect of body size on the rate of decomposition in a temperate region of South Africa. Forensic Sci. Int. 231, 257–262 (2013).CAS 
    PubMed 

    Google Scholar 
    Valverde, I., Espín, S., María-Mojica, P. & García-Fernández, A. J. Protocol to classify the stages of carcass decomposition and estimate the time of death in small-size raptors. Eur. J. Wildl. Res. 66, 1–13 (2020).
    Google Scholar 
    Goff, M. L. in Current Concepts in Forensic Entomology (eds. Amendt, J., Goff, M., Campobasso, C. & Grassberger, M.) 1–24 (Springer, 2010). https://doi.org/10.1007/978-1-4020-9684-6_1Pittner, S. et al. A field study to evaluate PMI estimation methods for advanced decomposition stages. Int. J. Legal Med. 134, 1361–1373 (2020).PubMed 
    PubMed Central 

    Google Scholar 
    Probst, C. et al. Estimating the postmortem interval of wild boar carcasses. Vet. Sci. 7, 6 (2020).PubMed Central 

    Google Scholar 
    Cambra-Moo, Ó., Delgado-Buscalioni, Á. & Delgado-Buscalioni, R. An approach to the study of variations in early stages of Gallus gallus decomposition. J. Taphon. 6, 21–40 (2008).
    Google Scholar 
    Oates, D., Coggin, J., Hartman, F. & Hoilien, G. Guide to Time of Death in Selected Wildlife Species. (Nebraska Technical Series No. 14. Lincoln, N.E., Nebraska Game and Parks Commission, 1984).Hewadikaram, K. A. & Goff, M. L. Effect of carcass size on rate of decomposition and arthropod succession patterns. Am. J. Forensic Med. Pathol. 12, 240–265 (1991).
    Google Scholar 
    Zhou, C. & Byard, R. W. Factors and processes causing accelerated decomposition in human cadavers—An overview. J. Forensic Leg. Med. 18, 6–9 (2011).PubMed 

    Google Scholar 
    Cockle, D. L. & Bell, L. S. Human decomposition and the reliability of a ‘Universal’ model for post mortem interval estimations. Forensic Sci. Int. 253(136), e1-136.e9 (2015).
    Google Scholar 
    Azevedo, R. R. & Krüger, R. F. The influence of temperature and humidity on abundance and richness of Calliphoridae (Diptera). Iheringia. Série Zool. 103, 145–152 (2013).
    Google Scholar 
    Barnes, K. M. in Wildlife Forensic Investigation: Principles and Practice (eds. Cooper, J. & Cooper, M.) 149–160 (CRC Press, 2013).Mann, R. W., Bass, W. M. & Meadows, L. Time since death and decomposition of the human body: Variables and observations in case and experimental field studies. J. Forensic Sci. 35, 103–111 (1990).CAS 
    PubMed 

    Google Scholar 
    Gliksman, D. et al. Biotic degradation at night, abiotic degradation at day: Positive feedbacks on litter decomposition in drylands. Glob. Change Biol. 23, 1564–1574 (2017).ADS 

    Google Scholar 
    Araujo, P. I., Grasso, A. A., González-Arzac, A., Méndez, M. S. & Austin, A. T. Sunlight and soil biota accelerate decomposition of crop residues in the Argentine Pampas. Agric. Ecosyst. Environ. 330, 107908 (2022).
    Google Scholar 
    Fernández-Palacios, J. M. & Martín-Esquivel, J. L. Naturaleza de las Islas Canarias: Ecología y Conservación. (Turquesa, 2001).Kenward, M. G. & Roger, J. H. An improved approximation to the precision of fixed effects from restricted maximum likelihood. Comput. Stat. Data Anal. 53, 2583–2595 (2009).MathSciNet 
    MATH 

    Google Scholar 
    R Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing. http://www.r-project.org (2020).Bates, D., Mächler, M., Bolker, B. M. & Walker, S. C. Fitting linear mixed-effects models using lme4. J. Stat. Softw. 67, 1–48 (2015).
    Google Scholar 
    Kuznetsova, A., Brockhoff, P. B. & Christensen, R. H. B. lmerTest package: Tests in linear mixed effects models. J. Stat. Softw. 82, 1–26 (2017).
    Google Scholar 
    Zeileis, A. & Hothorn, T. Diagnostic checking in regression relationships. R News 2, 7–10 (2002).
    Google Scholar 
    Halekoh, U. & Højsgaard, S. A Kenward–Roger approximation and parametric bootstrap methods for tests in linear mixed models-the R package pbkrtest. J. Stat. Softw. 59, 1–30 (2014).
    Google Scholar 
    Fox, J. & Weisberg, S. An {R} Companion to Applied Regression, Second Edition. (Sage, 2011).Bartoń, K. MuMIn: Multi-Model Inference. (R Package Version 1.43.6, 2019).De Rosario-Martinez, H., Fox, J. & R Core Team. Package ‘phia’ Title Post-Hoc Interaction Analysis. (R Package Version 0.2–1, 2015).Nakagawa, S. & Schielzeth, H. A general and simple method for obtaining R2 from generalized linear mixed-effects models. Methods Ecol. Evol. 4, 133–142 (2013).
    Google Scholar 
    Vass, A. Beyond the grave—Understanding human decomposition. Microbiol. Today 28, 190–192 (2001).
    Google Scholar 
    Gill-King, H. in Forensic Taphonomy: The Postmortem Fate of Human Remains (eds. Haglund, W. D. & Sorg, M. H.) 93–104 (CRC Press, 1996). https://doi.org/10.1201/9781439821923.sec2Campobasso, C. P., Di Vella, G. & Introna, F. Factors affecting decomposition and Diptera colonization. Forensic Sci. Int. 12, 18–27 (2001).
    Google Scholar 
    Austin, A. T., Araujo, P. I. & Leva, P. E. Interaction of position, litter type, and water pulses on decomposition of grasses from the semiarid Patagonian steppe. Ecology 90, 2642–2647 (2009).PubMed 

    Google Scholar 
    Brandt, L. A., Bonnet, C. & King, J. Y. Photochemically induced carbon dioxide production as a mechanism for carbon loss from plant litter in arid ecosystems. J. Geophys. Res. Biogeosci. 114, G02004 (2009).ADS 

    Google Scholar 
    Lee, H., Rahn, T. & Throop, H. An accounting of C-based trace gas release during abiotic plant litter degradation. Glob. Chang. Biol. 18, 1185–1195 (2012).ADS 

    Google Scholar 
    Zepp, R. G., Erickson, D. J., Paul, N. D. & Sulzberger, B. Interactive effects of solar UV radiation and climate change on biogeochemical cycling. Photochem. Photobiol. Sci. 6, 286–300 (2007).CAS 
    PubMed 

    Google Scholar 
    Archer, M. S. Rainfall and temperature effects on the decomposition rate of exposed neonatal remains. Sci. Justice J. Forensic Sci. Soc. 44, 35–41 (2004).Simmons, T., Adlam, R. E. & Moffatt, C. Debugging decomposition data—Comparative taphonomic studies and the influence of insects and carcass size on decomposition rate. J. Forensic Sci. 55, 8–13 (2010).PubMed 

    Google Scholar 
    Spicka, A., Johnson, R., Bushing, J., Higley, L. G. & Carter, D. O. Carcass mass can influence rate of decomposition and release of ninhydrin-reactive nitrogen into gravesoil. Forensic Sci. Int. 209, 80–85 (2011).CAS 
    PubMed 

    Google Scholar 
    Tracqui. in Encyclopaedia of Forensic Sciences (eds. Siegel, J. A., Saukko, P. J. & Max, M. H.) 1357–1363 (Academic Press, 2000).Riding, C. S. & Loss, S. R. Factors influencing experimental estimation of scavenger removal and observer detection in bird–window collision surveys. Ecol. Appl. 28, 2119–2129 (2018).PubMed 

    Google Scholar  More

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    The relationships between growth rate and mitochondrial metabolism varies over time

    The experiments were approved by the French Ethics Committee in charge of Animal Experimentation (no.2019072411491441) and were in accordance with institutional and ARRIVE guidelines.Animal collection and husbandryIn May 2019, juvenile European sea bass, Dicentrarchus labrax (Linnaeus 1758) (6 months old, mass 5 g), were transferred from a fish farm (Turbot Ichtus, Trédarzec, France) to the Ifremer rearing facility (Plouzané, France). Fish were kept in a common tank for 5 months, maintained under a 12 L: 12 D photoperiod, and fed at satiety three times a week using commercial pellets (Neo Start, Le Gouessant, Lamballe, France).In October 2019, fish (n = 40) were anaesthetized (Tricaïne; 125 mg L−1), weighed (41.5 ± 1.8 g, MCE11201S-2S00-0, Sartorius, Göttingen, Germany), and implanted subcutaneously with an identification tag (RFID; Biolog-id, Bernay, France). The fish were then randomly allocated to ten replicate 400 L tanks supplied with open-flow, fully aerated seawater (oxygen saturation  > 95%, salinity 32 ppt), thermo-regulated during winter to avoid falling below 13 °C, and fed at satiety three times a week. Temperature was recorded weekly. To account for the potential effect of temperature variation over the duration of the trial (15.5 ± 0.5 °C, range: 13.1–17.9 °C) on growth, a correlations analysis was performed between temperature and specific growth rate (SGR). No statistical relationship was found between SGR and temperature (Spearman R2 = 0.060, P = 0.596). Additional fish (n = 40) were present in the tanks (final density: n = 8 per tank) for the need of another project.Growth measurementsBody mass (BM) was measured about every four weeks from October 2019 to June 2020. The fish were fasted for 48 h and anesthetized before each BM measurement (± 0.1 g). The specific growth rate (% day-1) was estimated as follows:$${text{Specific~Growth~Rate}} = ~frac{{ln left( {final~BM} right) – ln left( {initial~BM} right)}}{{{text{days~elapsed}}}} times 100$$In March 2020, a red muscle biopsy sample was collected from fish to measure the mitochondrial metabolic traits. Past growth was defined as specific growth rates before the analysis of mitochondrial metabolic traits (past specific growth rate, SGRpast). SGRpast were calculated using the BM at the muscle biopsy as the final BM and the BM at 7, 11, 16, and 20 weeks before the muscle biopsy as the initial BM (Fig. 1). Future growth was defined as specific growth rates after analysis of mitochondrial metabolic traits (future specific growth rates, SGRfuture). SGRfuture were calculated using the BM at 4, 8, and 12 weeks after the muscle biopsy as the final BM and the BM at the muscle biopsy as the initial BM. In European sea bass, most of the somatic growth occur within the first 3 to 5 years of life, so several months of growth measurement at the juvenile stage might be representative of the overall growth of the animal.Figure 1Experimental design. Juvenile European sea bass (n = 40) were weighted about every four weeks over a 32-week period. At week 20, a biopsy of red muscle was used for mitochondrial assay. Specific growth rates (SGR) were calculated relative to the time of the biopsy. Past growth rate corresponds to SGR calculated before the biopsy, and future growth rate corresponds to SGR calculated after the biopsy.Full size imageMuscle biopsy procedureMuscle biopsy was performed as a non-lethal means of sampling tissue for the mitochondrial assay while allowing us to determine future growth rate. Fish were anaesthetized with tricaine (as above), weighed (76.7 ± 3.6 g), and biopsied. A skin incision ( More

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    Signals of local bioclimate-driven ecomorphological changes in wild birds

    Study areaWe conducted field studies in both regions from August to March, each year from 2012 to 2016. In north India, we selected the two traditional breeding colonies of the Painted Storks, viz., the Delhi Zoo (28° 36′ N 77° 14′ E) and Keoladeo National Park (KNP) (27° 17′ N 77° 52′ E), Bharatpur, Rajasthan (Fig. 1). In the Delhi Zoo, close to the river Yamuna, the Painted Storks nest in the traditional heronries with other colonial nesters, Little Cormorant, Indian Cormorant, Black-headed Ibis, and Night Heron38. The KNP, a Ramsar site spread over 29 km2, situated at the confluence of the rivers Gambhir and Banganga on the western edge of the Gangetic basin, supports diverse fauna, flora, and a mosaic of habitats, wetlands, woodlands, scrub forests, grasslands, and heronries39. In 2013, we recorded 680 adults and 310 nests in the Delhi Zoo and 1584 adults and 430 nests of Painted Storks in the KNP.We selected the Vedanthangal Bird Sanctuary (VBS), the nesting colonies at Melmaruvathur Lake, and Koonthankulam Bird Sanctuary (KBS). The KBS & VBS are the newly declared Ramsar sites in Tamil Nadu, south India. The VBS (12° 32′ 02″ N and 79° 52′ 29″ E) is a 40.3-hectare community reserve effectively protected by the state Forest Department, Tamil Nadu, and Vedanthangal villagers40. It is the oldest breeding waterbird reserve in south India, located 85 km southwest of Chennai. More than 40 species of waterbirds, both residents and migrants, live here. Along with the other 17 heronry species, the Painted Storks build nests every year from November to April during its breeding season. The Painted Stork nesting colonies at Melmaruvathur Lake (12° 25′ 53″ N and 79° 49′ 36″ E) are about 20 km away from the VBS. Here, the Painted Storks build nests at 1.8–5 m above the water level, on trees of Acacia nilotica and Barringtonia acutangula on mounds surrounded by water41. In 2012, we recorded a total of 3185 nests in the VBS, with a maximum number of nests belonging to Spot-billed Pelican (1050 nests) followed by Painted Stork (550 nests), Asian Open-bill (770 nests), and others.Birds have been breeding in Melmaruvathur Lake since 2013, and we counted 80 nests of Spot-billed pelican, 45 nests of Oriental White Ibis, and 56 nests of Painted Stork during the winter of the year 2014. The Lake is spread over 0.19 km2 with islets (mounds) with four clusters of Acacia nilotica and Barringtonia acutangula trees. Rainwater and domestic sewage from the neighboring residential complex are the primary water source, and recreational boating attracts a large crowd visiting the Melmaruvathur temple41. KBS (8° 29′ 44″ N and 77° 45′ 30″ E) is about a 1.3 km2 protected area, declared a bird sanctuary in 1994 and an Important Bird Area40. It comprises Koonthankulam and Kadankulam irrigation tanks actively protected and managed by the local community. We noticed the frequent failures of breeding events due to water shortages related to monsoon failures in VBS and KBS. In 2015, we also observed Painted Storks’ breeding failure across northern India for unknown reasons; therefore, data could not be collected for those periods.Bioclimatic variablesWe obtained the bioclimatic variable, particularly temperature at 2 m height for all the four study sites, from the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) Prediction of Worldwide Energy Resource (POWER) Project funded through the NASA Earth Science/Applied Science Program. The monthly average data from 2010 to 2020 was downloaded from the POWER Project’s Hourly 2.0.0 version on 2022/01/04.Digital images of Painted Storks collected under field conditionsUsing Binoculars (Olympus 10X50), Digital Cameras (Canon 5D Mark III and Sony handy-cam), we monitored and recorded all active nests with juveniles and adult Painted Storks twice a week. The nests were on trees, 3–7 m in height, and chicks and adults were visible, which aided the photography. Nests were numbered for our records by taking note of tree branching patterns, the nest’s position on the tree, and other local identification marks. Numbering the nests helped us identify the individuals associated with a given nest and avoided re-recording the same individual (pseudoreplication). Storks show site fidelity42,43, and hence we assumed the same breeding pairs occupied the same nesting site.During the initial months of the breeding seasons, pairing and copulations of the breeding pairs could be readily noticeable. We took consecutive photographs when they were copulating at the nest. After disengagement following the copulation, the birds (male and female) standing side by side at the nest were also photographed. The first author noted all the relevant spatial orientations of males and females during each copulation event in the field notes. Thus nearly 100 copulations involving different individuals of the Painted Storks pair were photographed. To minimize measurement errors, we selected for further analysis only the images of males and females standing parallel and close to each other, perpendicular to the camera. Since we used the digital images of the free-living Storks, we did not have the freedom to choose all morphological features resulting in some missing values. Therefore, we selected a hundred and forty-eight individuals for the analysis from nearly 1500 localized adults. The technique has an efficiency of less than 10% of the population, more efficient than the traditional capture, measure, and release of individuals. Though many individuals were recorded, only a few were subjected to the analyses. Moreover from the digital images, not all the morphological characters of the individuals were measured. The birds’ orientation towards the camera assumes importance because the correct direction ensures maximum exposure of body parts in the picture. In many pictures, correct orientation was missing as the birds were behind other individuals or branches of the trees or leaves. Therefore, selecting the right digital image becomes crucial. Keeping all the above criteria, we filtered images that were later included in the analysis.Calibrations of subject-distance using Exif MetadataWe extracted the EXIF metadata from each JPEG image of Painted Stork. EXIF metadata includes the filename, type, date, and time of the image captured, image width and height in pixels, camera model, lens information, field of view, focal length, and subject-distance. The subject-distance (Painted Stork distance from the camera) being a critical variable and its Exif metadata were standardized with the following equation.$${text{Subject{-}distance}} = 0.7864 times {text{(EXIF subject{-}distance)}}^{{1.0301}}$$
    (1)
    Using the Eq. (1) derived from an earlier study5, we regressed actual subject-distance with the Exif subject-distance from the images. Then multiplying with the field of view, available as Exif metadata (angle of view) with standardized subject-distance (Eq. 1), the total image size (length and width) in metric units was estimated. We excluded the cropped or manipulated images because Image (size) estimation is possible only for the images coming straight from the camera with EXIF tags. The methodological details for calibration and estimation of in-situ measurements of the morphological variables are given in Mahendiran et al.5.Measurements of the morphological variablesWe created a TPS file for JPEG images of Painted Storks with the TPSUtility Program44. Using the TPS file in the TPSDig (v. 2.17) program44, we measured the selected characters (morphological variables) in pixels. Later, it was used along with the total image size to estimate the size of the specific morphological features in metric units, following Mahendiran et al.5. Ten different morphological variables were measured: Bill length (upper and lower mandible), tibia & tarsus length of both legs, distances among the ear, nostril and corners of the mouth, and body length. We estimated the dimensions of the rigid body parts, viz., bill length, tibia, and tarsus using the given methodology13,15,21. Bill length is the distance from the tip of the upper mandible to the beginning of skin corners near nostrils, the proximal end of the beak (marked as ‘a’ in Fig. 3); Tibia length is the distance from the joint of the tibia-tarsus to the feathers (marked as ‘b’ in Fig. 3); Tarsus length is the distance between the tibia-tarsus joint and foot (marked as ‘c’ in Fig. 3). We took measurements of each individual’s right and left legs and other characters, viz., inter-distances among the nostril, corner of the eye, corner of the mouth on each side (marked as ‘d’, ‘e’, ‘f’ in Fig. 3). Body depth is the distance from the base of the neck near the breast to the tip of the tail (marked as ‘g’ in Fig. 3).Data analysisWe performed the statistical analysis in R45, primarily through the nlme, ggbiplot, nnet, tidyverse, devtools packages. We did not have the freedom to measure a few morphological variables due to the problems mentioned above, which led to missing values in the datasets. We filled the missing values with the impute function using the R Core team45 through mice & VIM packages. When the missing values are high in numbers, we discard the data rather than use the impute function. Since almost about 70% of the lower mandible values were missing, we discarded them and ended up having only nine morphological variables in the final analysis. Moreover, the lower mandible is movable, with the mouth being open and closed, producing a considerable variation in measurements.We designed the matrix (Individuals × Region × Sex) representing the intraspecific variations concerning the region and sexes of Painted Storks46. The individuals are in rows (R), their region in column (C1), and sex in column (C2). We considered the regional variations as a sequence of the latitudinal gradient of the study sites. The values of the individuals (R) were the selected morphological variables. This matrix helped us investigate the critical questions relating to eco-geographic variations and sexual dimorphism.To determine whether temperature varied between study sites, we conducted a two-way ANOVA to analyse the effect of study sites (between North India (DZ & KNP) and South India (VBS & KBS)) and months of the year on the temperature at 2 m. For each character, Dimorphism Index (DI) was calculated as a mean value of female divided by the mean male, multiplied by 100, following the method of Urfi and Kalam15. We estimated the general body size of Painted Storks from the selected morphological variables through Principal Component Analysis (PCA) and tested hypotheses on Eco-geographic variations (Bergmann’s or Allen’s rules)2,47 and the sexual dimorphism15,48. The dimension reduction through PCA was carried out after the imputation as there were a few missing values. Body depth was omitted only for the principal component analysis due to many missing values. However, the values of all the characters are presented in the summary statistics in Table 1. The first principal component is characterized as a measure of size, and subsequent components describe various aspects of shape; therefore, it is considered a measure of general body size15,48,49. The PC1 indicated the body size variation, and PC2 revealed leg length variation (tibia and tarsus). We used nested ANOVA to test their body size variation between regions and sexes. The sexes nested within the region explained the eco-geographic rules and sexual selection patterns.Using a multinomial logistic regression model, we compared the Painted Storks’ northern male (NM), southern male (SM), and female (SF) with the reference category, northern female (NF). Then, we classified the data through multinomial log-linear and feed-forward neural network models. We predicted the Painted Stork’s region and sex using the Machine Learning (ML) algorithms through open-source software Waikato Environment for Knowledge Analysis (WEKA.3.9.5) implemented in Java50. WEKA has standard Machine learning/data-mining algorithms with pre-processing tools generating insightful knowledge from the Painted Storks’ morphological data.Using the R and Python interfaces, we used different ML software frameworks, libraries, and computer programs, viz., TensorFlow and Keras, and extensively explored the WEKA workbench environment to predict the sex and region of the Painted Stork. We used the k-fold cross-validation (k = 10) to avoid overlapping test sets, including splitting the data into k subsets of equal size, using each subset for testing and the remainder for training. We analyzed using the WEKA on a Lenovo ThinkPad P53s Mobile Workstation with the 8th Gen Intel® Core i7 @ 1.80 GHz processor, 48 GB DDR4 Memory, NVIDIA® Quadro® P520 with 2 GB GDDR5 Graphics. The performance criteria for all the eight models were assessed by using the Precision (TP/(TP + FP)), Recall (TP/(TP + FN)), Area under Curve (AUC) = (Sensitivity + Specificity)/2, Accuracy = (TP + TN)/(TP + TN + FP + FN), where TP, TN, FN and FP are the acronyms of true positive, true negative, false negative and false positive, respectively. We used the WEKA experimenter environment to test the statistical significance of the selected Machine Learning algorithms. We performed the Paired T-tester based on the number of correctly classified instances and areas under the curve. More

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    Save the world’s forest giants from infernos

    Gigantic trees occur in only a few regions on Earth. Some of the world’s largest eucalypts, for example, are on the island of Tasmania, off southeastern Australia. As wildfires increase in severity and frequency as a result of climate change, we urge the authorities to protect these trees by adopting measures similar to those applied to safeguard California’s redwood forests.
    Competing Interests
    The authors declare no competing interests. More