and other, usually manmade, objects as well as electrocutions and shootings. Only 14% of the 71 deaths were due to apparent starving. Data showed some owls appeared to incur injuries but healed and survived. More evidence was found in wintering snowy owls in New York of healed fractures, though some may require surgery to recover. 537 wintering birds in Saskatchewan were studied based on fat reserves, which were superior in females over males and adults over juveniles; while 31% of females lacked fat reserves, at least 45% of males found starving or in a state of infirmity were males and 63% turned into Wildlife rehabilitation centres were also males. In British Columbia, of 177 snowy owl deaths, of owls to die, only a small percentage were due to natural causes, such as assumed starvation at 13% and 12% were "found dead". One fledgling on Fetlar died due to pneumonia and Staphylococcus, while a second died from Aspergillosis. Evidence shows that in Utqiaġvik during exceptionally prolonged rains (i.e. 2 to 3 days), nest-departed young were vulnerable to starvation, leading to hypothermia and pneumonia. Due to their natural history, the snowy owl may be affected more severely by blood parasitism than other raptors, due to lowered immunity. Conversely, they appear to have lower levels of ectoparasites such as chewing lice than other large owls per large samples from Manitoba. The snowy owls averaged about 3.9 chewing lice per host against 7.5 for great grey owls and 10.5 for great horned owls. Status This species presence and numbers is dependent on amount of food available. In "lemming years", snowy owls can appear to be quite abundant in habitat. Numbers of snowy owls are difficult to estimate even within studies that take place over decades due to the nomadic nature of adults. The population of Scandinavia has long been perceived as very small and ephemeral with Finland holding 0–100 pairs; Norway holding 1–20 pairs and Sweden holding 1–50 pairs. A low breeding population within European Russia has been estimated to hold 1,300–4,500 pairs and Greenland to have 500–1,000 pairs. Other than northern part of the American continent, a majority of the snowy owl's breeding range is in northern Russia, but overall estimates are not known. An exact count of 4,871 individuals were seen on surveys between the Indigirka and Kolyma rivers. The numbers estimated by Partners in Flight and other authors by the 2000s