July 12. This is an extended and corrected version of the original post, with the numbers from June 1-9 added, making the month complete.
Completing the season (starting May 16, when a bird and a rat were delivered) would be nice but would also mean a lot of work.
The first version can still be found on Looduskalender http://www.looduskalender.ee/n/en/node/496
Summary of the last 30 days (1 - 30 June 2016) of food delivery to the young Buzzards on the nest
In addition to watching the web cam directly, I have searched the videos in the archive in detail for food items brought to the nest during June.
On June 1 the oldest young was 20 days old and the youngest 17. On June 30 they were 49 and 46 days old. On June 26 the young started to leave the nest but came back to eat. The morning of July 1 was the last time food was delivered to the nest and eaten there, and the evening of that day the last young was seen on the nest. Because the cam lost its sound on the morning of June 6, it is not known how long the young stayed in the vicinity of the nest.
The number of food items delivered to the nest per day.
![Image](https://lh3.googleusercontent.com/-HLPKGsI2enw/V4SttPI_ABI/AAAAAAAAOLM/W9dcp3IGjwQFKCb_ssXy2MmMAtVdr65jQCCo/s454/1_Buzz16_numbday.jpg)
On June 11 nothing was delivered because of the bad weather.
I have no explanation for the low number on June 10.
Variation in the food per day as a percentage of the daily totals.
![Image](https://lh3.googleusercontent.com/-frQO9tYpTN4/V4SttBr5EkI/AAAAAAAAOLQ/q-n379s5gfIp8sPCBSF1euNzf7h16GH8ACCo/s529/2_Buzz16_percday.jpg)
Compare with the first chart to get an idea of the actual numbers.
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Mammals were mainly voles, but also rats, mice, moles and shrews, usually impossible to tell witch species. Most voles were likely of the most common Microtus species, some perhaps Bank vole and one or two almost certainly Striped field mouse. Small rodents and shrews often were swallowed whole, even when the young were still pretty small but rats and moles always caused problems. It could take the mother over one hour to feed a rat.
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Amphibians were Common Toads and frogs of unknown species. Often it was difficult to see whether it was toad or frog. Toads seemed more popular than frogs, although the young usually needed the help of mother to eat them, while they had no problems with frogs. It could take over twenty minutes to deal with a toad.
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Invertebrates were always earthworms, likely of various species. Some were very big. Most were caught after rainy weather, most notably on June 12 (with 15 worms) and the following four days. Almost no worms after June 16 and none at all before June 12.
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Birds were difficult to identify to species. Usually it were juvenile songbirds or waders/meadow birds (plovers?). Quite a few looked like pipits or thrushes. Others were possibly a Skylark and a White Wagtail. On June 13 an unidentified unusual big bird was brought and eaten. On June 7, an exceptional but easy to recognize prey was a Great Spotted Woodpecker.
Distribution of the four categories over the total of 317 prey items
![Image](https://lh3.googleusercontent.com/-3gb2Z1d3rmc/V4StsjbsisI/AAAAAAAAOLI/ZY2W_eNP5EwGn3DjwCkeslDvteRyfPYSQCCo/s378/3_Buzz16_percmonth.jpg)
With 60% small mammals are clearly the most important food. The volume of worms is much less than any of the other animals. Perhaps one average vole equals the weight of 20 worms. But in the end it is the nutritional value that counts. Bones and fur or feathers are swallowed but later regurgitated in pellets.