When walking on mountain trails, we often don’t think about how many functions meadows, alpine tundra, or pastures serve. And it is not only about preserving the environment in which valuable species of plants live or having a place to herd sheep. These open habitats are an indispensable element of life for birds of prey, both common and very rare ones.
Buteo buteo pic. T. Wnęczak Pernis apivorus pic. T. Wnęczak
Why is it so?
Open habitats are where numerous insects, reptiles, and small mammals live. Those animals constitute a food base for birds of prey, such as the common buzzard, the honey buzzard, and the red-backed shrike.
Does a HONEY buzzard eat HONEY? A few words about food specification.
All birds of prey are carnivores, however, their food can be very diverse. Despite its Polish name [“myszołów” – literally “mouse catcher” – translator’s note], the common buzzard’s (Buteo buteo) diet is not based on rodents only. Except for microtuses, voles, and mice, the common buzzard is also eager to hunt lizards, small birds, and insects. Among the latter, insects from the Orthoptera order and beetles dominate.
Unlike the common buzzard, the honey buzzard (Pernis apivorus) feeds only on social insects: wasp, hornet, and bumblebee larvae. Sometimes when digging up a nest, it also easts the adult insects.
The abovementioned bird species are a great example of the predators’ division based on their nutrition pattern. Species characterised by polyphagia, such as the common buzzard, the white-tail eagle, and the golden eagle, fully use the available food base, and the composition of their diet changes throughout the year. Species characterised by monophagia use the variety of prey to a limited extent and feed on only one type of food. Except the honey buzzard, other birds which can be classified as monophages are: the sparrowhawk, which mainly eats birds, the osprey, which mainly eats fish, and the snake eagle, which mainly hunts snakes.
Phaneroptera falcata pic. A. Smolarska
The meadow under a magnifying glass
Insects are a supplement of the diet of birds of prey. In most cases, these are insects from the Orthoptera and Coleoptera orders. Those invertebrates are an important source of protein and chitin, which is similar to cellulose. Although chitin serves no energetic function, it aids the process of removing food residue from the organism. In Poland, both beetles and Orthoptera grow to relatively large sizes, their preferred habitat are pastures and meadows with low vegetation, and they are most active during the sunny hours of the day. These factors make them an easy prey for the birds.
The “inconspicuous butcher”
The inconspicuous red-backed shrike (Lanius collurio) is a particularly surprising bird of prey. This bird, which is not much bigger than a sparrow, was first described by the Swedish biologist Carl Linnaeus, and thanks to its predatory nature it gained the Latin name “Lanius”, which means “butcher”. These accusations are based not on the red-backed shrike’s manner of feeding, but on the method of storing food. This ruthless predator waits in hiding for its victims, which are mainly beetles, grasshoppers, and crickets, and after catching larger prey, it impales them on bush thorns, pointy branches, or parts of wire in fences. This method helps it to eat its food piece by piece, and at the same time, after the bird is satisfied, it serves as a stockpile for another time.
Lanius collurio pic. A. Smolarska
Protection of non-forest habitats
The Project No. LIFE12 NAT/PL/000081 titled “Protection of Non-forest Communities in the Beskids’ Landscape Parks”, thanks to the active measures of environmental protection, causes the animals to be more eager to return to the mountain glades and meadows. However, this process requires time, and activities such as mowing meadows or herding sheep should not be one-off events. It is important for the owners and users of the non-forest land to know how many functions are served by such measures, so for more information we invite you to: www.lifebeskidy.com.pl