Threats Status and conservation of the golden eagle







almost threats golden eagles attributable, directly or indirectly, human activities. human-sourced threats include: habitat change, persecution, poisoning (often directed @ other species) , collisions man-made objects. widespread unintentional threat golden eagles humans urbanization , human-population growth have made areas historically used eagles unsuitable both in terms of habitat , prey availability. habitat destruction in north america had, late 19th century, driven golden eagles regions used inhabit. in southern california , colorado front range, has been proved via long-term population , habitat surveys. in western china, main threats golden eagles land development, use of pesticides , captures falconry. fires since 1980 have caused large-scale losses of shrubs , jackrabbit habitat in areas used eagles throughout intermountain west of north america. wildfires burned more 40,000 hectares of scrublands between 1981 , 1987 in morley nelson snake river birds of prey national conservation area affected nesting populations adversely. nesting success @ burned territories in snake river canyon declined after major fires. abandoned burned territories have been subsumed neighboring pairs, resulting in decreased number of nesting pairs.


where disturbance regular, breeding failure golden eagles more frequent. inferred in 1982 scottish breeding bird survey when disturbances heavy in highlands. sheep farmers , egg-collectors leading cause of disturbances @ nests. recreation, forest management , development projects such road construction, mining or power generation other potential sources of disturbances. when disturbed humans @ nest, parents leave nest period of 2 hours, reduced provisioning rates, endangered eggs or young predation, overheating, chilling or desiccation. human intrusion within 750–1,500 m (2,460–4,920 ft) of nests can cause disturbance. nesting success found reduced in norway during years easter holidays fell early, due volume of vacationers in countryside in these years during pivotal stages of nesting. during study in wrangell – st. elias national park , preserve of alaska, experimenters camped within 400 m (1,300 ft) of active nests, led reduced food delivery , nest attendance parents, @ 800 m (2,600 ft), @ distance disturbance of nesting behavior seemed decrease considerably. topography of landscape , location of nest can affect how closely nest can approached without disturbance. mining , various types of energy development occur in eagle nesting , wintering habitat. practice of surface coal mining threatens limited nesting sites in wyoming. in italian apennines, high levels of nesting failures have been attributed directly disturbance, due increased tourism in remote mountain areas, construction of new roads , mining. aggressive behavior golden eagles due human presence near nest considered exceptional , result in minor injuries if any, particularly bold eagle may attempt dissuade human trespasser. golden eagles sensitive human disturbance while not nesting. experimental studies showed pedestrians, caused flushing @ 105–390 m (344–1,280 ft), more cause wintering golden eagles in colorado flush vehicles, @ 14–190 m (46–623 ft). study showed golden eagles more sensitive human disturbance during winter several other raptor species, including bald eagles.


the intentional killing of golden eagles has been conservation hurdle species. golden eagles intentionally killed due fear of loss of livestock , game species. despite findings of virtually every study of losses of stock golden eagles has revealed actual amount of livestock killed eagles negligible , financial restitution conservation organizations should not necessary, including studies funded farming organizations or governmental programs seeking justify “control” of golden eagles. while illegal in countries today, hunting, trapping , poisoning may still occur. in united states, golden eagle given federally protected status in 1963. occasionally, golden eagles may caught in trap lines laid out capture mammalian predators. in study conducted in scotland, areas broken down low disturbance areas (with low human presence , limited history of persecution), moderate areas (where minor disturbances occur, unintentionally hill-walkers or intentionally egg-collectors) or severe disturbance areas (where persecution, heavy disturbance , considerable egg-collecting believed still occur). in low disturbance areas, 45% of nests failed, in moderate disturbance areas 74% failed , in severe disturbance areas 93% of nesting attempts failed. 73 out of 147 inaccessible nesting sites in study (50%) produced fledglings, whereas more accessible nests produced fledglings in 21 out of 68 nests (31%).


poisoning, both intentional , unintentional, threat. usual targets of carrion-poisoning species such coyotes, red fox , gray wolves, considered pests threaten livestock. however, golden eagles targeted same reasons. main cause of mortality golden eagles in britain has been poisoning, 51 eagles have been verified killed poisoning 1980 2008 actual number killed higher. disproportionate amount of golden eagle poisonings in scotland 1981 2000 linked grouse moors (where grouse kept pleasure of shooting) , caused gamekeepers deliberately poisoning eagles , foxes keep stock of grouse high. estimated adult survival rate reduced 3% 5% in scotland intentional poisonings. in 1980s, california ground squirrels, considered agricultural pests, poisoned anticoagulant rodenticide, chlorophacinone. in turn, poisonings caused golden eagles, 1 of major natural predators of california ground squirrels, die in turn. @ least 10 individuals died in 1971 eating thallium(i) sulfate–laced pronghorn set out sheep ranchers in wyoming; despite public outcries, poisoning sheep ranchers continued 1980s. in 20th century, organochloride , heavy metal poisonings commonplace, these have declined due tighter regulations on pollution. in southern idaho, 10 out of 17 golden eagles examined found have had exposure lead. golden eagles did not prove susceptible poisoning pesticide ddt other large raptors, because of diet of mammals. eggs golden eagle nests collected after 1946 in north america had shell thicknesses similar (less 10% difference) collected in earlier years. however, in scotland egg shell thickness did decrease around 10% 1951 1965. dead golden eagle collected on island of lewis had highest concentration of organochlorine known modern bird in scotland. higher effects of organochlorines in scotland may due fact birds there consume relatively high quantity of seabirds, opposed north america, practice rare.


death collisions man-made structures , objects can serious local issue. electrocution or collision power lines has become increasingly significant cause of mortality since 20th century. juveniles birds more susceptible adults, being less cautious , physically adept. estimated 70 golden eagles may killed locally wind turbines each year in west-central california, of them being juveniles opposed adults tend remain on home ranges largely occur outside of wind farm area. collisions automobiles claim golden eagle lives, though instances of can increase in desolate areas during winter, when road-side prey or carrion may attract eagles.


in few cases, mankind has accidentally benefited golden eagles logging heavily wooded areas. has been recorded in 1800s , 1900s in appalachian mountains of eastern united states, reforestation has made habitat unsuitable nesting eagles, , in washington state, still holds breeding eagles in desolate areas have been logged. afforestation, commercial planting of non-native woodland, serious issue in scotland, largest amount of occurring in southwestern scotland, in argyll. during afforestation, land plowed , on 2,500 seedlings planted per hectare, exotic conifers including sitka spruce (picea sitchensis) , lodgepole pine (pinus contorta). woodland canopy closes , ground vegetation dies, making these dark , gloomy places until harvesting in 40 50 years. more 50% of land in scotland @ elevation of 200–600 m (660–1,970 ft) has been planted such. afforestation requires removal of sheep , fencing out or shooting deer, both important sources of carrion golden eagles. foraging areas of golden eagles have been confirmed not include afforested areas.








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