Ancient origin and maternal inheritance of blue cuckoo eggs

Maternal inheritance via the female-specific W chromosome was long ago proposed as a potential solution to the evolutionary enigma of co-existing host-specific races (or 'gentes') in avian brood parasites. Here we report the first unambiguous evidence for maternal inheritance of egg colouration in the brood-parasitic common cuckoo Cuculus canorus. Females laying blue eggs belong to an ancient (∼2.6 Myr) maternal lineage, as evidenced by both mitochondrial and W-linked DNA, but are indistinguishable at nuclear DNA from other common cuckoos. Hence, cuckoo host races with blue eggs are distinguished only by maternally inherited components of the genome, which maintain host-specific adaptation despite interbreeding among males and females reared by different hosts. A mitochondrial phylogeny suggests that blue eggs originated in Asia and then expanded westwards as female cuckoos laying blue eggs interbred with the existing European population, introducing an adaptive trait that expanded the range of potential hosts

Sex Allocation in Relation to Host Races in the Brood-Parasitic Common Cuckoo (Cuculus canorus)

Sex allocation theory and empirical evidence both suggest that natural selection should favour maternal control of offspring sex ratio in relation to their ability to invest in the offspring. Generalist parasites constitute a particularly interesting group to test this theory as different females commonly utilize different host species showing large variation in provisioning ability. The common cuckoo (Cuculus canorus) is a generalist brood parasite that lays its eggs in the nest of many different passerine birds, but each female tends to specialize on one particular host species giving rise to highly specialized host races. The different host species show large variation in their ability to invest in the parasitic offspring, presenting an opportunity for female cuckoos to bias offspring sex ratio in relation to host species quality. Here, we investigate host-race specific sex allocation controlling for maternal identity in the common cuckoo. We found no evidence of any significant relationship between host race and sex ratio in one sympatric population harbouring three different host races, or in a total of five geographically separated populations. There was also no significant association between host quality, as determined by species-specific female host body mass, and cuckoo sex ratio. Finally, we found no significant relationship between individual cuckoo maternal quality, as determined by her egg volume, and sex ratio within each host race. We conclude that the generalist brood-parasitic common cuckoo show no significant sex-ratio bias in relation to host race and discuss this finding in light of gene flow and host adaptations

Fugler i Norge 2001 – Rapport fra Norsk faunakomité for fugl (NFKF)

THE NORWEGIAN BIRD REPORT 2001 - a report on locally uncommon and scarce birds in Norway in 2001, by the Norwegian Birds Records Committee (NFKF) The basis of this report is the annual reports produced by the county rarities committees. For 2001 all the counties contributed to the report, although the Svalbard archipelago and Jan Mayen as well as Finnmark, Troms and Sogn & Fjordane countiesdid not produce own county reports. With the exception of the northernmost counties the report thus reflects fairly well observations from Norway in 2001. Readers should take care to note the geographical or time delimitation of the records stated for the different species, as stated in codes immediately after the scientific name of the species. The Norwegian Birds Records Committee (NFKF) has been publishing annual reports since 1991. Bewick’s Swan Cygnus columbianus numbers were the lowest since 1991, and also the occurrence of Lesser White-fronted Geese Anser erythropus at the traditional feeding and roosting site Valdakmyra, Porsanger (FI) were particularly scarce this spring (lowest since 1993). However, this could partly be explained by early arrival at the breeding sites due to unusually early snow melting. Gadwalls Anas strepera have occurred in steadily increasing numbers in Norway in recent years, and 2001 was the best year to date for this species. The number of White-billed Divers Gavia adamsii was the highest reported since 1991. This species is probably a common winter guest from Nord-Trøndelag county and northwards. Manx Shearwaters Puffinus puffinus were also recorded in good numbers in 2001, the third best year since 1991. There was a further increase in numbers at the recently established colonies of Great Cormorant Phalacrocorax carbo of the subspecies sinensis at Øra (ØF), where the first confirmed breeding was in 1997. White-tailed Eagles Haliaeetus albicilla have steadily increased in numbers and also expanded their breeding distribution southwards. Breeding is now documented in both Rogaland and Vest-Agder counties and a further expansion is expected. The Osprey Pandion haliaetus is another species that is steadily expanding its range in Norway. Avocets Recurvirostra avosetta, however, is now very unusual, with only one individual in 2001, a record low number. Several shorebirds, such as Northern Lapwings Vanellus vanellus, Great Knots Calidris canutus, Sanderlings Calidris alba, Jack Snipes Lymnocryptes minimus, Woodcocks Scolopax rusticola and Bar-tailed Godwits Limosa lapponica wintered in higher numbers than usual in 2001, probably due to winter temperatures above normal. Pomarine Skuas Stercorarius pomarinus occurred in record numbers in 2001, and also Long-tailed Skuas Stercorarius longicaudus were recorded in good numbers on migration. Furthermore, numbers of Iceland Gulls Larus glaucoides recorded were the highest since 1991, while Turtle Doves Streptopelia turtur experienced another poor year. Good numbers of Snowy Owls Bubo scandiaca were still present in 2001 after the record setting year of 2000. Kingfishers Alcedo atthis also had a good year with one breeding attempt recorded. The number of Hoopoes Upupa epops was the second best since 1991. The occurrences of Richard’s Pipits Anthus richardi, Barred Warblers Sylvia nisoria and Marsh Warblers Acrocephalus palustris were the highest ever recorded, and Red-throated Pipits Anthus cervinus showed another good year, equalling the record numbers of 2000. Blackcaps Sylvia atricapilla wintered in record numbers. Stonechats Saxicola torquata, Red-breasted Flycatchers Ficedula parva, Great Grey Shrikes Lanius excubitor and Arctic Redpolls Carduelis hornemanni all experienced second best numbers since 1991. However, traditional winter invasion species such as Pine Grosbeaks Pinicola enucleator and Two-barred Crossbills Loxia leucoptera appeared in low numbers in 2001. The Hawfinch Coccothraustes coccothraustes still shows a marked increase in the north of its distribution, especially in the Trøndelag counties, while the situation is not as bright for Ortolan Buntings Emberiza hortulana, which continues to decline in numbers and now are in danger of becoming lost as a member of the Norwegian avifauna

Are Cuckoos Maximizing Egg Mimicry by Selecting Host Individuals with Better Matching Egg Phenotypes?

Background: Avian brood parasites and their hosts are involved in complex offence-defense coevolutionary arms races. The most common pair of reciprocal adaptations in these systems is egg discrimination by hosts and egg mimicry by parasites. As mimicry improves, more advanced host adaptations evolve such as decreased intra- and increased interclutch variation in egg appearance to facilitate detection of parasitic eggs. As interclutch variation increases, parasites able to choose hosts matching best their own egg phenotype should be selected, but this requires that parasites know their own egg phenotype and select host nests correspondingly. Methodology/Principal Findings: We compared egg mimicry of common cuckoo Cuculus canorus eggs in naturally parasitized marsh warbler Acrocephalus palustris nests and their nearest unparasitized conspecific neighbors having similar laying dates and nest-site characteristics. Modeling of avian vision and image analyses revealed no evidence that cuckoos parasitize nests where their eggs better match the host eggs. Cuckoo eggs were as good mimics, in terms of background and spot color, background luminance, spotting pattern and egg size, of host eggs in the nests actually exploited as those in the neighboring unparasitized nests. Conclusions/Significance: We reviewed the evidence for brood parasites selecting better-matching host egg phenotypes from several relevant studies and argue that such selection probably cannot exist in host-parasite systems where hos

Coevolution in Action: Disruptive Selection on Egg Colour in an Avian Brood Parasite and Its Host

Trait polymorphism can evolve as a consequence of frequency-dependent selection. Coevolutionary interactions between hosts and parasites may lead to selection on both to evolve extreme phenotypes deviating from the norm, through disruptive selection.Here, we show through detailed field studies and experimental procedures that the ashy-throated parrotbill (Paradoxornis alphonsianus) and its avian brood parasite, the common cuckoo (Cuculus canorus), have both evolved egg polymorphism manifested in discrete immaculate white, pale blue, and blue egg phenotypes within a single population. In this host-parasite system the most common egg colours were white and blue, with no significant difference in parasitism rates between hosts laying eggs of either colour. Furthermore, selection on parasites for countering the evolution of host egg types appears to be strong, since ashy-throated parrotbills have evolved rejection abilities for even partially mimetic eggs.The parrotbill-cuckoo system constitutes a clear outcome of disruptive selection on both host and parasite egg phenotypes driven by coevolution, due to the cost of parasitism in the host and by host defences in the parasite. The present study is to our knowledge the first to report the influence of disruptive selection on evolution of discrete phenotypes in both parasite and host traits in an avian brood parasitism system

Adaptive responses of animals to climate change are most likely insufficient

Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species. © 2019, The Author(s)

En vurdering av mulige fuglekollisjonsreduserende tiltak i Smøla vindpark

May, R., Nygård, T. & Stokke, B.G. 2022. En vurdering av mulige fuglekollisjonsreduserende tiltak i Smøla vindpark. NINA Rapport 2152. Norsk institutt for naturforskning. Smøla vindpark ble satt i drift i 2002, og regelmessige søk etter fugler som har kollidert med turbinene har avdekket at spesielt lirype og havørn er utsatt for kollisjoner. Lirype ser primært ut til å kollidere med selve turbintårnene, mens havørn kolliderer med turbinbladene. I forbindelse med forlengelse av anleggskonsesjonen for Smøla vindpark har NVE satt som vilkår at Smøla Vind 2 AS skal legge fram forslag til avbøtende tiltak for å redusere omfanget av kollisjoner mellom fugl og vindturbiner i vindkraftverket. Denne rapporten er ment å danne grunnlaget for et slikt forslag. Det gis en kortfattet oppsummering av hovedutfordringene knyttet til fuglekollisjoner i Smøla vindpark, med fokus på arts-, tids-, steds- og turbinspesifikke faktorer som kan påvirke kollisjonsrisikoen. For havørn består de fleste kollisjoner av voksne individer tidlig i hekkesesongen. Dette er ikke overraskende siden dette er en periode med spesielt høy flygeaktivitet. Både for havørn og lirype er det tilsynelatende noen turbiner som medfører større kollisjonsrisiko enn andre (så-kalte kollisjons-hotspots), men disse er ikke sammenfallende for de to artene. Det gis en oversikt over mulige kollisjonsreduserende tiltak etterfulgt av en anbefaling rundt hvilke tiltak som anses å være mest hensiktsmessige for Smøla vindpark. Tidligere forsøk med kollisjonsreduserende tiltak på Smøla har vist en meget lovende effekt av maling av turbinblad (havørn og fugler generelt) og -tårn (lirype). Det anbefales å videreføre disse tiltakene ved å male «problemturbiner» som forårsaker spesielt høy kollisjonsrisiko. For havørn kan det i tillegg vurderes å fjerne skogholt med sitkagran nær vindkraftanlegget. Disse benyttes som rasteplasser og kan medføre forhøyet kollisjonsrisiko. Midlertidig nedstenging av turbiner er et annet tiltak som kan gjennomføres ved bruk av IdentiFlight-teknologi. For lirype kan man vurdere å bedre habitatkvaliteten i områder utenfor vindkraftanlegget som et kompenserende tiltak. Det er inkludert kostnadsestimater for de ulike tiltakene. En evaluering av tiltakenes effektivitet må i første rekke baseres på søk etter død fugl (effekt av maling og fjerning av sitkagran), linjetransekter (habitatkvalitet for ryper) og IdentiFlight (unnvikelsesatferd hos havørn etter maling) for å sammenligne før- og etter-situasjonen.May, R., Nygård, T. & Stokke, B.G. 2022. An assessment of possible mitigation measures for reducing the risk of bird turbine collisions at the Smøla wind farm, Central Norway. NINA Report 2152. Norwegian Institute for Nature Research. Smøla wind farm has been operational since 2002. Regular searches for avian collision victims have disclosed that willow grouse and white-tailed sea eagles are especially prone to collide. Grouse primarily appears to collide with the turbine towers, while the sea eagles collide with the turbine blades. In connection with the extension of the operational license for Smøla wind farm, NVE has set as a condition that Smøla Vind 2 AS shall submit a proposal for mitigating measures to reduce the extent of collisions between birds and wind turbines in the wind power plant. The present report is intended to form the basis of such a proposal. A brief summary is given of the main challenges associated with bird collisions in the Smøla wind farm, with a focus on species, time, place and turbine-specific factors that can affect the risk of collision. For sea eagles, most collisions involve adult individuals during the early breeding season. This is not surprising since this is a period of particularly high flight activity. For both sea eagles and grouse, there are apparently some turbines that carry a greater risk of collision than others (so-called collision hot-spots), but these do not coincide for the two species. An overview of possible collision reduction measures is given, followed by a recommendation on which measures are considered to be most appropriate for Smøla wind farm. Previous experiments with collision reduction measures at Smøla have shown a very promising effect of painting turbine blades (sea eagles and birds in general) and towers (grouse). It is recommended to extend these measures by painting "problem turbines" which cause a particularly high risk of collision. For sea eagles, it can also be considered to remove forest patches with sitka spruce near the wind power plant. These are used as resting areas and can lead to an increased risk of collision. Temporary shutdown of turbines is another measure that can be implemented using IdentiFlight technology. For grouse, one can consider improving the habitat quality in areas outside the wind farm as a compensatory measure. Cost estimates for the various measures are included. An evaluation of the effectiveness of the measures must primarily be based on searches for dead birds (effect of painting and removal of sitka spruce), line transects (habitat quality for grouse) and IdentiFlight (avoidance behavior in sea eagles after painting) to compare the before and after situation

Spatial Multi-Criteria Decision Analysis (SMCDA) toolbox for Consensus-based Siting of Powerlines and Wind-power plants (ConSite)

Hanssen, F., May, R., Van Dijk, J., Stokke, B.G., De Stefano, M. 2018. Spatial Multi-Criteria Decision Analysis (SMCDA) toolbox for Consensus-based Siting of Powerlines and Wind-power plants (Con-Site). NINA Report 1455. Norwegian Institute for Nature Research. The expansion of wind energy development causes both societal and environmental concerns worldwide. Traditional land use planning approaches however limit addressing such concerns adequately. The scale and complexity of emerging renewable energy construction projects enforce the development of improved plan- and decision support tools that ensure democratic and cost-effective processes securing qualified decision making. The multiplicity of criteria and actors involved in decision-making processes requires holistic approaches that enable capturing the variety stakeholder views from technological, economic, societal and environmental perspectives. As a response to this societal need, the Norwegian Institute for Nature Research (NINA) has developed a Spatial Multi-Criteria Decision Analysis tool (SMCDA) for siting of onshore wind-power plants and associated infrastructure such as powerlines and roads. The tool ConSite (Consensus Based Siting) aims to ensure socially acceptable, environmentally friendly and cost-effective siting, routing and design of wind-power plants and powerlines. ConSite helps to identify and justify decisions taken with respect to both transparency and verification. ConSite is based on current developments in stakeholder dialogue theory, GIS-based Spatial Multi-Criteria Decision Analysis (SMCDA) and decision theory. The ConSite framework is structured into the operational steps of a classical SMCDA and combines stakeholder dialogue with multi-criteria assessment. The objective of the toolbox is to identify areas with the lowest possible conflict level and the highest possible production level. Dialogue with affected stakeholders and documentation of relevant expertise is used to provide information about, and to consider the relative importance of (weighting of) the different stake-holder interests. This helps to identify potential land use conflicts in a “conflict-map”. The “conflict-map” is used together with wind resource maps to identify which areas are most optimal for wind power development. This way ConSite helps to structure the decision problem, balance conflicting interests and identify relevant decision strategies based on a holistic evaluation of risk and trade-off between different alternatives. ConSite can be used to evaluate different scenarios by visualizing the spatial consequences of different decision strategies This report exemplifies the practical usage of the ConSite toolbox. ConSite has previously been successfully implemented in spatial planning of wind-power development in Lithuania, and validated through a power line routing case study in Sør-Trøndelag County (Bevanger et al., 2014 & Hanssen et al., 2014). Further development to integrate the ecosystem services concept into an adaptive landscape planning context, helps making the complexity of social-ecological systems more comprehensible for involved stakeholders. This enables the application of ConSite across sectoral interests (e.g. renewable energy, road infrastructure, urban development and fish farming). ConSite can thus help decision makers to secure socially acceptable, environmentally friendly and cost-effective siting and optimal design of renewable construction projects. The current version of the ConSite SMCDA toolbox framework is developed for a desktop GIS platform. To increase the access to and user-friendliness of ConSite, NINA has the ambition to move the ConSite SMCDA framework to an online GIS-platform. This development will be based on an evaluation of user needs, a detailed requirement specification and system prototyping.Hanssen, F., May, R., Van Dijk, J., Stokke, B.G., De Stefano, M. 2018. Spatial Multi-Criteria Decision Analysis (SMCDA) toolbox for Consensus-based Siting of Powerlines and Wind-power plants (Con-Site). NINA Rapport 1455. Norsk institutt for naturforskning. Den omfattende utbyggingen av vindkraft forårsaker både samfunnsmessige og miljømessige bekymringer verden over. Tradisjonell arealplan-metodikk har en begrenset evne til å adressere alle disse behovene på en tilstrekkelig måte. Omfanget av og kompleksiteten i nye energiprosjekter vil tvinge frem utviklingen av forbedrede plan- og beslutningsstøtteverktøy for å sikre mer demokratiske, kostnadseffektive og kvalifiserte beslutningsprosesser. Mengden av kriterier og aktører som er involvert i plan- og beslutningsprosesser krever en helhetlig tilnærming for å kunne fange opp alle berørte interesser innenfor teknologiske, økonomiske, samfunnsmessige og miljømessige perspektiver. Som en respons på dette samfunnsbehovet har NINA gjennom CEDREN1 utviklet et romlig multi-kriteriebasert verktøy for konsensusbasert lokalisering av landbasert vindkraftverk og kraftledninger. Verktøyet har fått navnet ConSite (kortform for Consensus Based Siting) og bidrar til samfunnsmessig akseptabel, miljøvennlig og kostnadseffektiv plassering og utforming av vind-kraftverk. ConSite kan bistå med å identifisere og begrunne vedtatte beslutninger både med hensyn til transparens og etterprøvbarhet. Verktøyet er basert på gjeldende kunnskap innenfor dialogteori, GIS-baserte beslutnings-systemer og beslutningsteori. ConSite-rammeverket er strukturert som et klassisk romlig multi-kriteriebasert beslutningsverktøy og kombinerer dialog med multi-kriteriaanalyse. Målet med verktøyet er å identifisere områder som har lavest mulig konfliktnivå og høyest mulig produksjonsnivå. Dialog med berørte parter og dokumentasjon av relevant fagkunnskap benyttes til å fremskaffe informasjon om, og å vurdere den relative betydningen av (vektingen av) de ulike arealinteressene. Dette bidrar til å identifisere potensielle arealkonflikter i et eget «konfliktkart». Konfliktkartet brukes sammen med vind-ressurskart til å identifisere hvilke områder som egner seg best til utbygging av vindkraft. ConSite er på denne måten behjelpelig med å strukturere beslutningsproblem, balansere motstridende interesser og identifisere relevante beslutningsstrategier basert på en helhetlig vurdering av risiko og avveining mellom ulike alternativ. ConSite kan brukes til å vurdere ulike scena-rier med tanke på romlige konsekvenser av ulike beslutningsstrategier. Denne rapporten inneholder eksempler der ConSite har vært benyttet. Dette for å illustrere den praktiske bruken av verktøyet. ConSite er tatt i bruk til planlegging av vindkraftutbygging i Litauen og validert gjennom en case-studie med trasévalg for kraftledninger I Sør-Trøndelag (Bevanger et al., 2014 & Hanssen et al., 2014). Videre utvikling for å integrere økosystemtjenester i landskapsplanlegging er under planlegging. Dette vil bidra til å gjøre kompleksiteten av sosio-økologiske systemer mer forståelig for berørte interessenter i en plansak. Dette vil også bidra til å gjøre ConSite mer anvendelig på tvers av ulike sektorer (f.eks. energiprosjekter, veibygging, byutvikling og fiskeoppdrett). ConSite kan på denne måten hjelpe beslutningstakere med å sikre en samfunnsmessig akseptabel, miljøvennlig og kostnadseffektiv lokalisering og utforming av fornybar-energiprosjekter. Den nåværende versjonen av ConSite er utviklet på en desktop GIS-plattform. For å gjøre verktøyet mer tilgjengelig og brukervennlig har NINA som ambisjon å migrere ConSite over til en online GIS-plattform. Dette utviklingsarbeidet vil bli basert på en vurdering av brukernes behov, kravspesifisering og system-prototyping

Do Ostriches Struthio camelus reject parasitic eggs by making use of colour as a cue?

The Ostrich communal breeding system involves several females laying in a single nest. Only the ‘major’ female and the territorial male, however, provide parental care from incubation to fledging of chicks. Eggs are turned and displaced frequently upon the onset of incubation, and the major female evicts excess eggs out of the nest when the number of eggs is above a specific threshold level. A previous study indicated that the major female ostrich recognises her own eggs and selectively evicts eggs of minor females based on size, shape and shell texture. Our aim was to investigate if accepted and ejected eggs differ in colour characteristics. We quantified colour by measuring egg reflectance spectra, which were subsequently analysed using a visual model approach. Within clutches, there were no significant differences in colour between accepted and ejected eggs. These results suggest that female ostriches do not discriminate against foreign eggs based on deviations in colour.OSTRICH 2010, 81(3): 247–25

Miljøkonsekvenser knyttet til småskala fornybar kraftforsyning. En litteratur-studie

Stokke, B. G., May, R., Bevanger, K. og Nygård, T. 2017. Miljøkonsekvenser knyttet til småskala fornybar kraftforsyning. En litteraturstudie. - NINA Kortrapport 66. 24 s. Verdens energiforbruk øker i takt med behov fra den teknologiske utviklingen. Energi fra fornybare kilder som sol, vind og biomasse øker årlig, men utgjør fortsatt bare en liten andel sam-menlignet med kull og gass. Fornybare energikilder blir ofte betraktet som miljømessig mer «rene» enn konvensjonelle fossile energikilder som olje og gass, først og fremst på grunn av betydelig lavere utslipp av CO2 til atmosfæren. Det er allikevel på det rene at også fornybare energikilder kan ha negative miljøkonsekvenser. Det er tre hovedrisikofaktorer for dyreliv ved utbygging av energi. For det første vil anleggene og deres infrastruktur kunne føre til at arter blir fortrengt fra området. For det andre vil enhver ut-bygging føre til tap eller endring av habitater og areal som kan føre til fragmentering av viktige naturtyper. Dette vil igjen kunne medføre lavere tettheter hos arter som lever i slike områder. For det tredje vil man løpe en risiko for at dyr på en eller annen måte blir direkte påvirket av konstruk-sjonene, for eksempel gjennom fysisk kollisjon. De tre hovedrisikofaktorene kan ha ulike effekter på dyrelivet som alle kan bidra til at artenes bestandsstørrelse blir påvirket. I denne rapporten presenteres, på bakgrunn av en omfattende litteraturstudie, en sammenstilling av miljøkonsekvenser knyttet til produksjon av energi fra utvalgte fornybare energikilder. Mer spesifikt gjelder dette elektrisitet produsert ved bruk av solceller, biogassanlegg, hydrogenbrenselceller og vindturbiner, samt overføring av produsert elektrisitet via kraftledninger. Litteraturstudien viser at effekten på naturmiljøet av kraftledninger og vindturbiner er godt dokumentert. Det foreligger også et økende antall studier som har omhandlet miljøeffekter av solceller og annen teknologi knyttet til produksjon av solenergi. Når det gjelder energiproduksjon knyttet til biogass og brenselsceller er miljøeffekter knyttet til selve energiproduksjonen svært mangelfullt belyst så langt. Felles for alle energikildene er at studiene i all hovedsak har omhandlet storskala («utility scale») produksjon. Svært få studier har fokusert på effekter av småskalapro-duksjon. Vi har vurdert energikildene ut fra tilgjengelig kunnskap, men det bør bemerkes at dette i stor grad gjelder større anlegg. Grundige for- og etterundersøkelser er svært viktig for å utrede eventuelle konsekvenser på naturmiljøet. Optimal plassering, utforming og dimensjonering kan bidra til å redusere konflikten mellom naturmiljøet og energiproduksjonsanlegg inklusive deres infrastruktur som for eksempel kraftledninger. For å forhindre kollisjoner kan man merke linene med fugleavvisere eller legge kablene i jord på spesielt kollisjonsutsatte steder. Fuglevern på mastene kan redusere risikoen for elektrokusjon, mens solcellepaneler kan monteres på allerede eksisterende bygninger for å unngå at det unødvendig legges beslag på arealer. For vindturbiner kan man vurdere å anvende vertikalakslete vindturbiner (VAWT) for å minimere bruk av land- og luftarealet.TrønderEnergi A