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White-tailed eagles are more vulnerable to direct persecution than golden eagles since most nests are highly accessible for white-tailed eagle but not for golden eagles which usually nest in mountainous, precipitously rocky terrain, in contrast to sea cliff nests of which 67–87% were found to be accessible.<ref name=Love/><ref name="Ingólfsson"/><ref name=Christensen/> Before firearms were widely available in Scotland and Norway automatic traps were utilized wherein carrion was laid out to entice an eagle with a person hiding in a near subterranean trap waited until the eagle was distracted, at that point grabbing the eagle by the leg. Petrified by the darkness once dragged below, white-tailed eagles apparently offer no resistance once caught. However, habitat had to be favourable and even when conditions were correct, success at capture as such was low.<ref name=Love/><ref name=Willgohs/><ref name=Bannerman/> The main driver of declines before firearms and industrialized poisons was habitat alterations.<ref name=Love/> After about the 1840s, firearms became available and declines accelerated considerably, by 1916 the last nesting pair in all of Britain attempted to raise a brood on the [[isle of Skye]]. While other ecological factors have been considered in this decline, stringent research has shown the extirpation here was fully correlated to intentional, rapacious predation by man.<ref name=Love/><ref name=Bannerman/> Many [[gamekeeper]]s poisoned and shot eagles and destroyed nearly any nest they encountered. A few more enlightened landowners forbade the killing of eagles but there's evidence that the gamekeepers sometimes chose to destroy eagles regardless of the rule of law. On deer forest, eagles were tolerated later than in other British areas, but destructions accelerated there by the late 1800s.<ref name=Love/> Also many white-tailed eagles were poisoned by shepherds who considered it enemy of the flock.<ref>Hudson, W.S. (1906). ''British Birds''. Harper Collins.</ref> Elsewhere in Europe, persecution rates in the 19th and 20th century were just as drastic. In Romania, more than 400 white-tailed eagles were killed in two decades by a single hunter.<ref name=Bijleveld/> In Norway between 1959 and 1968, an average of 169 eagles were killed annually; with a maximum of 221 in 1961.<ref name=Willgohs/> Around the year 1860, an author estimated that about 400 were being killed annually throughout Germany.<ref name=Bijleveld/> Between 1946 and 1972 in eastern Germany, a total of 194 dead white-tailed eagles were found, about half of them shot, after governmental protection of the species had been instituted there.<ref name=Oehme/>
Top predators, especially those that are aquatic and coastal, are almost immediately vulnerable uponto exposure to [[DDT]]. Therefore, white-tailed eagles are highly susceptible to this pesticide, as are similar fish eaters, such as [[Eurasian otter|otters]], and bird eaters, such as [[peregrine falcon]]s. Distributed by man nearly across the developed world as an insecticide in the 1950s, by the early 1970s, authors found many species of bird experienced reduced egg shell thickness. Thus the incubating parents inadvertently crushed their normally hardy eggs and, in turn, many water birds and raptors had their nesting success dropped precipitously.<ref name=Newton>Newton, I. (2010). ''Population ecology of raptors''. A&C Black.</ref> In fact, the species was found to have the highest concentration of DDT of any European raptor.<ref>Jensen, S., Johnels, A. G., Olsson, M. & Westermark, T. (1972). ''The avifauna of Sweden as indicators of environmental contamination with mercury and chlorinated hydrocarbons'' . -Proc . XV Int. Ornithol . Congr., Leiden : 455–465</ref> Egg shell thickness was found down from {{convert|0.62|mm|in|abbr=on}} prior to 1935 from 1969 to 1975 down to only {{convert|0.52|mm|in|abbr=on}}, a 16% reduction.<ref>Joutsamo, E., & Koivusaari, J. (1976). ''White-tailed Eagle in Finland 1970–1976''. In Proceedings from the World Wildlife Fund Sea Eagle Symposium, Norway, September 1976.</ref> In Sweden, coastal birds were considerably more effected by DDT than the inland birds of Lapland, Sweden.<ref name=Helander3/> In eastern Germany, where pesticide use was heavy, only 1 out of 28 nesting attempts were known to succeed in 1976.<ref name=Love/> Overall, about 75% nesting attempts failed in western Germany, Finland and the Swedish Baltic area.<ref name=Love/> Other environmental pollutants affecting the species include heavy metals which affect individuals through [[bioaccumulation]]. The amount of white-tailed eagles killed by mercury poisoning rose from 6.4% during 1946–1957 to 24.6% in 1958–1965 in Germany.<ref>Oehme, G. (1969). ''Population trends in the white-tailed sea eagle in North Germany''. Peregrine Falcon Populations: Their Biology and Decline, pp. 351–352.</ref><ref>Koeman, J. H., Hadderingh, R. H., & Bijleveld, M. F. I. J. (1972). ''Persistent pollutants in the white-tailed eagle (''Haliaeetus albicilla'') in the Federal Republic of Germany''. Biological Conservation, 4(5), 373–377.</ref> It was estimated that pesticides and metal contaminations reduced the white-tailed eagle population in Hungary from 1957 to 1967 by about 50–60%.<ref name=Bijleveld/> Lead poisoning, caused by lead bullets left in carcasses that the white-tailed eagles will eat in winter, is also another issue faced by the species. Fatal and near fatal levels of lead exposure continues to be a major issue in the 21st century in many parts of the range, at least from Poland to Hokkaido.<ref>Kalisńska, E., Salicki, W., & Jackowski, A. (2006). ''Six Trace Metals in White-Tailed Eagle from Northwestern Poland''. Polish Journal of Environmental Studies, 15(5).</ref><ref>Kim, E. Y., Goto, R., Iwata, H., Masuda, Y., Tanabe, S., & Fujita, S. (1999). ''Preliminary survey of lead poisoning of Steller's sea eagle (Haliaeetus pelagicus) and white‐tailed sea eagle (''Haliaeetus albicilla'') in Hokkaido, Japan''. Environmental Toxicology and Chemistry, 18(3), 448–451.</ref><ref>Iwata, H., Watanabe, M., Kim, E. Y., Gotoh, R., Yasunaga, G., Tanabe, S., Masuda, Y. & Fujita, S. (2000). ''Contamination by chlorinated hydrocarbons and lead in Steller’s Sea Eagle and White-tailed Sea Eagle from Hokkaido, Japan''. In First Symposium on Steller’s and White-tailed Sea Eagles in East Asia. Wild Bird Society of Japan, Tokyo (pp. 91–106).</ref> Despite regulations on their usage, lead and mercury poisonings were found to be the cause of death of 61 white-tailed eagles found in Germany from 1993 to 2000.<ref>Kenntner, N., Tataruch, F., & Krone, O. (2001). ''Heavy metals in soft tissue of white‐tailed eagles found dead or moribund in Germany and Austria from 1993 to 2000''. Environmental Toxicology and Chemistry, 20(8), 1831–1837.</ref>
===Conservation measures===
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