Please look through the series of photos of Short-toed Eagles taken by Bernard Joubert in Haute-Loire /map/ in the past few years, showing the impressive variability of their appearance:
Snake eagle is one of the most elegant raptors in Europe. When observed at close range, one is amazed by the way it can change looks and attitudes. This can clearly be seen in these pictures taken in France (Massif central) in 2009, 2012 and 2016.
Bernard Joubert
The excellent online database featherbase.info contains high resolution photos of bird feathers, various statistical data on their dimensions, useful comparing tools which allow to identify species with high confidence. Also, you can add pictures of your own finds there. Specific information on Short-toed Eagle is available on the separate page.
Ildikó Baranyi is a wildlife photographer living in Romania. A lot of excellent pictures of the local nature are presented on her website. Among them you can find a photo-gallery dedicated to Short-toed Eagles. The eagles in intermediate and adult plumage, clear signs of the plumage replacement can be seen in the photos. All of them were taken in Romania, including ones of a 2cy individual summering in Europe.
This WordPress site is dedicated to identification of Raptors in the nature. The main idea was to provide easy uploading various pictures of birds of different age and sex, then, to describe and categorize them correctly, developing in this way a rich database for Raptors identification. All photos of any species can be found by one click, ones of Short-toed Snake Eagle as well. Descriptions of sex and age-related features are in English and Catalan.