Along with the pellets, there is likely to be nesting materials — grasses and soft vegetation, perhaps even some un-eaten small mammals and insects that are left there as a cache for when hunting becomes harder in winter months. Barn Owl Tree Roost Site.
Barn owls tend to nest away from dense human populations, frequenting barns and other agricultural buildings that are near to open rough grassland or river banks. Alternatively, and more naturally, they will nest in suitable mature trees — anything from a standalone tree in the middle of a field to a mature tree forming part of a hedgerow or woodland edge. The trunk diameter of trees at about chest height is a good way to estimate the age of the tree and the likelihood of a barn owl using it as a nest.
The guidance for barn owl survey methodology lists the common trees as such; in ash, sycamore and willow trees, 0. These figures are only guidelines however, and are not strict rules. In order to categorically state whether a barn owl is using one of the suitable nest sites, it must be ascertained whether the suitable trees and buildings are a Potential Nest Site, or an Active Roost Site.
The suitable sized trees as mentioned earlier are closely inspected to see if they have a big enough crack or hole that tend to naturally appear with age for a barn owl nest. Again, these are only guidelines, and therefore common sense plays a part in determining a Potential Nest Site. These are not nest sites, i. These will be marked with those features mentioned previously — splashes or streaks of droppings, pellets and feathers.
The chances of finding an Active Roost Site are much higher than finding a Potential Nest Site, as each owl will have several roost sites compared to one of two nest sites. Active Roost Sites can be found in any place where the owl may stop to feed or to rest.
Tending towards the same habitat of open grassland or woodland edges, the roost sites could include branches, beams, machinery and roofs, just about anywhere an owl can land and feel safe. The signs that indicate an Active Roost Site can be used to estimate how active the site is, whether it is regularly or occasionally used. Additionally, we can estimate when the site was last used, usually categorised as up to three years ago, or greater than 3 years ago.
It is rare that this level of information is required for a barn owl survey, however. If an Active Roost Site is found with only occasional pellets and feathers is indicative of a rarely used Active Roost Site, and may be classified as a Temporary Rest Site, though this level of distinction is rarely needed.
Contrary to popular belief, finding a barn owl or any other protected species on a proposed development site is not the end of the world, nor is it always a huge financial drain. Photo used with permission from Gerry Gutteridge. Connect With Us. Barn Owl faeces are watery and predominantly white although they can be black or black and white. They are sometimes seen on wooden roof beams, as splashes on the floor, on machinery, or in fact on anything that is underneath where the birds roost or perch.
A disassembled Barn Owl nestbox showing a compacted nest debris. A Barn Owl roost debris on a loft floor — comprising about pellets. Very small fluffy body feathers from a Barn Owl are typically white sometimes grey with a tiny quill. Larger feathers from the underparts are generally white. Upper body feathers have the classic golden hue with grey markings although the lower part of the feather is usually white.
Wing feathers are moulted systematically over a number of years. Females tend to moult between May and August, whilst males usually start moulting in July and finish around October. For more information on sexing male and female Barn Owls see our sexing Barn Owls photoguide.
Unlike the very small fluffy body feathers from an adult Barn Owl, nestling fluff is a temporary feather extension so it has no quill.
Gently tease the pellet apart using your fingers or tweezers. Although pellets do not smell, they are not faeces hands should be washed thoroughly with soap and water after this activity. Photos of bone identification for owl pellet analysis. Wild Barn Owls eat mainly small mammals such as voles, shrews and mice. Other less common items include rats, birds and frogs. The shapes of the bones, particularly the jawbones, can tell you what species of animal the owl has eaten.
You can also count how many prey items are contained within an individual pellet. Take a look at a our photos of owl pellet analysis to help you to identify bones.
Includes owl pellet analysis diagrams. Contains everything you need for owl pellet dissection — including a real Barn Owl pellet!
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