Scheduling tasks in production facilities are usually hybrid optimization problems of a large combinatorial nature. They involve solving, in near-real time, the integration of the operation of ...several batch units of continuous dynamics with the discrete manufacture of items in processing lines. Moreover, one has to deal with uncertainty (process delays, unexpected stops) and the management of shared resources (energy, water, etc.) including decisions made by plant operators: still, some tasks in the scheduling layers are done manually. Manufacturing Execution Systems (MESs) are intended to support plant personnel at this level. However, there is still much work to do in terms of performing automatic scheduling, computed in real time, that guides managers to achieve an optimal operation of such complex cyber-physical systems. This work proposes a closed-loop approach to handle the uncertainty arising when facing the online scheduling of supply lines and parallel batch units. These units often share some resources, so effects due to concurrent resource consumption on the system dynamics are explicitly considered in the presented formulation. The proposed decision support system is tested onsite in a tuna cannery, to handle short-term online scheduling of sterilization processes that deal with limited steam, carts, and operators as shared resources.
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IJS, KILJ, NUK, PNG, UL, UM
Anthropogenic mortality is a major cause of global mortality in terrestrial vertebrates. Quantifying its impact on the dynamics of threatened species is essential to improve their conservation. We ...investigated cause-specific mortality in Canarian houbara bustards (Chlamydotis undulata fuertaventurae), an endangered subspecies endemic to the Canary Islands. We monitored 51 individuals tagged with solar-powered GSM/GPRS loggers for an average of 3.15 years, and recorded 7 casualties at aerial lines (13.73% of the sample; 5 at power lines, 2 at telephone lines), 1 (1.96%) at a wire fence, 4 road kills (7.84%) and 1 case of predation by cat (1.96%). Cox proportional hazards models showed that anthropogenic and natural annual mortality rates were similar (respectively, 6.20% and 6.36% of the individuals). We estimate that 33-35 houbaras die each year in the Canary Islands due to anthropogenic causes. Population viability models using these data and juvenile productivity values obtained over seven years predicted the extinction of the species in 50 years. Eliminating anthropogenic mortality, the population could be recovered, but would still require management actions to improve habitat quality. Conservation measures to reduce anthropogenic mortality due to power line fatalities, roadkills and predation by cats, as well as to increase productivity, are urgently needed, particularly on Fuerteventura, where houbaras are on the brink of extinction.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Browning of surface waters, also known as brownification, is a process of decreasing water transparency, particularly in boreal lakes surrounded by intensively managed forests and wetlands. In this ...paper, we review the ecological consequences and ecosystem‐based management (EBM) of browning through a systematic review approach and adopt an interdisciplinary approach to formulating new governance of this complex phenomenon. To understand the effects of browning on the recreational value of freshwaters, we present primary survey data on public perceptions of recreational fishing tourists on water quality in Finland. We identify a need to develop EBM beyond the EU's Water Framework Directive (WFD) to fully account for the extensive implications of browning. We also highlight the need for a better understanding of the within‐lake microbial processes to estimate the browning‐associated changes in the greenhouse gas balance of lakes. Tourist perceptions of the quality of waterbodies in Finland were largely in agreement with the general proportion of waterbodies classified in a good or excellent ecological status class, but these perceptions may be detached from biological quality assessment criteria. Consequently, we suggest that the EBM of inland waters should improve the utilization of information on not only biogeochemical processes but also users' perspectives on aquatic ecosystems beyond the EU WFD.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Collision with electric power lines is a conservation problem for many bird species. Although the implementation of flight diverters is rapidly increasing, few well-designed studies supporting the ...effectiveness of this costly conservation measure have been published.
We provide information on the largest worldwide marking experiment to date, including carcass searches at 35 (15 experimental, 20 control) power lines totalling 72.5 km, at both transmission (220 kV) and distribution (15 kV-45 kV) lines. We found carcasses of 45 species, 19 of conservation concern. Numbers of carcasses found were corrected to account for carcass losses due to removal by scavengers or being overlooked by researchers, resulting in an estimated collision rate of 8.2 collisions per km per month. We observed a small (9.6%) but significant decrease in the number of casualties after line marking compared to before line marking in experimental lines. This was not observed in control lines. We found no influence of either marker size (large vs. small spirals, sample of distribution lines only) or power line type (transmission vs. distribution, sample of large spirals only) on the collision rate when we analyzed all species together. However, great bustard mortality was slightly lower when lines were marked with large spirals and in transmission lines after marking.
Our results confirm the overall effectiveness of wire marking as a way to reduce, but not eliminate, bird collisions with power lines. If raw field data are not corrected by carcass losses due to scavengers and missed observations, findings may be biased. The high cost of this conservation measure suggests a need for more studies to improve its application, including wire marking with non-visual devices. Our findings suggest that different species may respond differently to marking, implying that species-specific patterns should be explored, at least for species of conservation concern.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
The home range of an animal is determined by its ecological requirements, and these may vary depending on many intrinsic and extrinsic factors, which are ultimately driven by food ...resources. Investigating the effects of these factors, and specifically how individuals use food resources within their home ranges is essential to understand the ecology and dynamics of animal populations, and to establish conservation measures in the case of endangered species. Here, we investigate these questions in the Canarian houbara bustard, an endangered subspecies of African houbara endemic to the Canary Islands.
Methods
We analysed GPS locations of 43 houbaras in 2018–2021, using solar GSM/GPRS loggers provided with accelerometers. We assessed (1) the variation in their home range and core area with kernel density estimators in relation to several intrinsic and extrinsic factors and (2) their foraging habitat selection.
Results
Home ranges were smallest during the breeding season (November–April), when rains triggered a rapid growth of herbaceous vegetation. Displaying males and nesting females had smaller home ranges than individuals not involved in reproduction. Both sexes used almost exclusively non-cultivated land, selecting low density
Launaea arborescens
shrublands, pastures and green fallows as foraging habitats. Heavier males used smaller home ranges because they spent more time displaying at a fixed display site, while heavier females moved over larger areas during the mating period, probably visiting more candidate mates. During the non-breeding season (May–October), both sexes showed larger home ranges, shifting to high density shrubland, but also partly to cultivated land. They selected sweet potato fields, green fallows, alfalfas, orchards and irrigated fields, which offered highly valuable food resources during the driest months of the year.
Conclusions
Our study shows how Canarian houbara, originally a desert-dwelling species that uses mostly shrublands and pastures, has developed the necessary adaptations to benefit from resources provided by current low intensity farming practices in the study area. Maintaining appropriate habitat conditions in the eastern Canary islands should constitute a key conservation measure to prevent the extinction of this endangered houbara subspecies.
Volunteer‐based roadkill monitoring schemes, including road carcass sampling, can represent considerable advances with respect to classical methods employed in conservation biology. We studied the ...genetic diversity, structure, and dynamics of the European polecat (Mustela putorius) across the Iberian Peninsula. We used samples of road carcasses collected by volunteers because this carnivore is an elusive species otherwise difficult to monitor with standard field protocols. We gathered 238 samples obtained from 2004 to 2022 from 13 different areas (8–31 samples/area). Using microsatellite loci, we identified 4 genetic units with gene flow among 3 of them in the Iberian Peninsula. The genetic variability was steadily low in 1 of the areas (Girona) for all the parameters evaluated. This area is also genetically isolated from the other studied areas. The inbreeding coefficient was significant in the north‐ and south‐Iberia units, and we did not detect a bottleneck signature in any of the 4 genetic units. Future conservation actions should consider the genetic dissimilarity among detected units and elucidate the ecological factors that have led to the observed genetic patterns.
The European polecat genetic structure in the Iberian Peninsula includes 4 major genetic units with gene flow among them with no low genetic variability. The northeastern genetic unit is isolated and threatened. Volunteer sampling of roadkills was very succesfull.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•Great bustards significantly avoid trellis vineyards, especially at closer distances.•Great bustards show a neutral or preference for proximity to traditional vineyards.•Trellis vineyards surface ...increases would decrease proportion of suitable habitat.•Regulation and legislative changes are advised for trellis vineyard.
A significant restructuring of vineyards is currently taking place in the European Union (EU) as a result of the implementation of a restructuring and conversion of vineyards regulation (CE 1493/1999) in southwest Europe, so that trellis vineyards are rapidly replacing traditional vineyards (e.g., surface area from 18.1 % in 2010 to 34 % in 2015 in Castilla-La Mancha, Central Spain). These changes may influence patterns of space use in birds, which may avoid modified habitats. We assess how the location of traditional and trellis vineyards might influence the distribution of great bustard (Otis tarda), a globally threatened species. We estimate Resource Selection Functions (RSFs) to quantify the relative probability of use of different areas by the great bustards, and use the RSF’s to simulated scenarios of conversion from traditional to trellis vineyards (low - 10 %, medium - 30 %, and high rate - 60 %) to quantify the potential impact of such modifications on the availability of suitable great bustard habitat. Our results revealed that great bustards significantly avoid trellis vineyards, especially at closer distances. Transition scenarios show how an increase in the proportion of traditional vineyards converted to trellis vineyards greatly decrease the proportion of suitable habitat for great bustard. Compared to current conditions, the percentage loss of suitable habitat increased steadily with higher rates of converted vineyards, up to 60 % loss of suitable habitat at the highest rate of conversion. Because the effect of transforming traditional vineyards to trellis vineyards depends both on the amount of habitat available for bustards before the transformation occurs and on the overall area covered by vineyards, a correct estimation of transformable vineyard area will require a case-by-case assessment to assure a low impact on bustard populations. We identified alternative vineyard management options that would mitigate impacts on the great bustard populations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An endangered subspecies of the African houbara bustard, the Canarian houbara (Chlamydotis undulata fuertaventurae), is endemic to the Canary Islands off southern Morocco (Lanzarote, Fuerteventura, ...and La Graciosa islands). This population decreased over the last centuries because of hunting and egg collection, and was close to extinction in Lanzarote around the middle of last century. Later, the species recovered because of hunting bans, but in Fuerteventura a significant decline has again occurred in the last decades and houbaras are on the brink of extirpation on that island. We describe the genetic characteristics and recent evolutionary history of this subspecies to provide essential information for the evaluation of the conservation actions implemented and for the development of new measures to prevent further declines and local extirpations. We amplified microsatellite loci to infer genetic variability, population structure, and gene flow. The subspecies exhibited relatively high genetic variability but reduced heterozygosity. In spite of high gene flow among locations and islands, we identified 2 genetic units: 1 comprising La Graciosa and Fuerteventura islands, and the other restricted to Lanzarote. We detected genetic bottlenecks and subsequent inbreeding in both units, with a reduced effective number of alleles in Lanzarote compared to Fuerteventura‐La Graciosa. This genetic structure may be explained by human‐induced historical population declines and an associated bottleneck effect, particularly in Lanzarote. Conservation measures should aim to recover the houbara population of Fuerteventura, improving survival of adults and juvenile productivity, and to ensure that genetic flow continues among breeding locations and islands to recover the original population structure (an unique genetic unit over the range of the species) and prevent further genetic deterioration, which could lead to extirpation of this endemic subspecies.
We describe the genetic characteristics and dynamics, and the recent evolutionary history of the Canarian houbara bustard, an endemic to the Canary Islands. We identified high gene flow and two genetic units, with genetic bottlenecks and subsequent inbreeding in both of them, and propose potential management actions to avoid its extinction.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Data on SARS-CoV-2 infection in wildlife species is limited. The high prevalences found in mustelid species such as free-ranging American minks (
Neovison vison
) and domestic ferrets (
Mustela ...putorius furo
) justify the study of this virus in the closely related autochthonous free-ranging European polecat (
Mustela putorius
). We analysed lung samples from 48 roadkilled polecats collected when the human infection reached its highest levels in Spain (2020–2021). We did not detect infections by SARS-CoV-2; however, surveillance in wild carnivores and particularly in mustelids is still warranted, due to their susceptibility to this virus.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Increasing levels of tourism represent a risk to species susceptible to human-induced disturbance and habitat degradation. With the outbreak of the SARS-COV-2 pandemic (COVID-19), preventive health ...measures reduced human mobility worldwide. Using high-resolution telemetry, we assessed the influence of tourism on flight frequency and anthropogenic mortality in an endangered endemic island bird, the Canarian houbara bustard. We monitored 51 individuals equipped with GSM-GPRS loggers and accelerometer technology before, during and after the COVID-19 lockdown in Canary Islands. Our results showed a significant correlation between number of tourists and flight frequency of houbaras, which fly rarely, almost only when disturbed. During pre- and post-COVID periods, birds made a 325 % higher flight rate than during COVID confinement. When tourism declined, the number of rental vehicles on the islands also declined, and there was a decrease in houbara fatalities at overhead lines and roadkills. The fact that flights originated closer to roads and tracks than would be expected by chance supports the conclusion that many of these flights were caused by human or vehicle traffic. These results suggest that a high presence of tourists and vehicles in houbara areas was most likely a decisive factor responsible for the increase in anthropogenic houbara mortality. Our study represents a clear example of the negative effects of unsustainable tourism in a fragile and humanized island environment and urges to regulate tourism and vehicle traffic, implement corrective measures on overhead lines and roads, and establish restricted areas for outdoor recreation, especially where human-wildlife conflict involves endangered species.
•High-resolution GPS and accelerometer data to study the effects of confinement COVID-19•Effects of COVID-19 confinement on the flight behaviour of an island endangered bird.•Massive tourism increases the flight frequency of the Canarian houbara bustard.•The excessive presence of tourists in houbara areas increase anthropogenic mortality.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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