Sparrowhawk (species)

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Sparrowhawk
Sparrowhawk (Accipiter nisus), male

Sparrowhawk ( Accipiter nisus ), male

Systematics
Class : Birds (aves)
Order : Birds of prey (Accipitriformes)
Family : Hawk species (Accipitridae)
Genre : Hawks and sparrowhawks ( Accipiter )
Type : Sparrowhawk
Scientific name
Accipiter nisus
( Linnaeus , 1758)

The sparrowhawk ( Accipiter nisus ) is a bird of prey and belongs to the hawk family (Accipitridae). The females are almost twice as large and heavy as the males. In the hunter's language the males are called Sprinz (while all other birds of prey use the term Terzel for the male ).

Sparrowhawks are closely tied to the forest, but now breed in many parts of Europe in urban green spaces. They feed mostly on small and medium-sized birds up to the size of a pigeon . After a sharp decline in Europe after 1950, caused by the insecticide DDT , the population recovered from around 1975 and is still increasing in many places.

Surname

The name of the sparrow is a compound of two Old High German nouns: sparo (" sparrow ") and aro (" aar , eagle "). Old High German spar (a) wāri and from it Middle High German  sparwaere, sperwaere and sperbaere denotes a "sparrow-eagle", so a "little eagle".

description

Sparrowhawk in flight

Sparrowhawks are typical representatives of the predominantly forest-dwelling genus Accipiter (hawks and sparrowhawks). With a body length of 35–41 cm and a wingspan of 67 to 80 cm, females are slightly larger than a kestrel and come close to small male goshawks in size. Sparrowhawk males are 29–34 cm long and have a wingspan of 58–65 cm. The wings are relatively short, wide and rounded at their tips, the thrust is relatively long. These features do not allow extreme flight speeds, but high maneuverability in tight spaces. Legs and toes show clear adaptations to the hunt for small and fast songbirds. The legs are comparatively long and very thin. The middle toe is greatly elongated, all toes have pronounced holding berries, which allow a gapless closure when grasping and thus can also hold individual feathers. The claws are long and very pointed.

Foreground: adult female
Behind: adult male
Right back: bird in youthful dress

Sparrowhawks show a very clear sexual dimorphism in terms of color. Colored (adult) male sparrowhawks are gray-blue on the upper side. The underside is white and finely banded transversely (" spattered "). This banding is orange-red on the trunk to an extent that varies greatly in width and extent. Some males are almost monochrome orange on the underside of the trunk, in other birds the transverse banding is only clearly orange on the flanks and brown on the rest of the trunk. The neck shows fine vertical dotted lines that vary in a similar way to the drawing of the trunk; in extreme cases, the neck is also solid red-orange. Females are less colorful than males. They are slate-gray-brown on the upper side, the lower side bands can also be orange to a large extent on the flanks; however, this orange markings are only as extensive as in males in exceptional cases.

Young birds are brownish on top until the first moult , all cover feathers have a light brown beige border. The underside is white with a transverse banding that is wider and often teardrop- or heart-shaped.

The large plumage shows in all clothes a clear banding on a white to beige-brown, in young birds on a yellowish background. The legs are yellow, as is the wax skin of the beak. The iris is light yellow in young birds, dark yellow in adult females and mostly orange in males. The beak is black, blue-gray at the base.

The sex dimorphism in terms of height and weight is extreme in this species. The difference is so great that there is no area of ​​overlap between the sexes when it comes to body measurements. For example, adult males of the nominate form A. nisus nisus from Germany had a wing length of 192 to 209 mm, on average 199 mm, females measure 223-247 mm, on average 234 mm. Adult males weigh 105–165 g, mean 137 g, females 192–290 g, mean 234 g. So males only reach about 60% of the body weight of females. Sparrowhawks are among the smallest members of the genus Accipiter , male sparrowhawks are among the smallest birds of prey that breed in Central Europe.

In Central Europe it can be confused primarily with the hawk . In the case of seated birds, the distinction is usually simple, hawks are much larger and stronger, this is particularly noticeable when looking at the legs and the head. Hawks never show orange on the chest and belly and have a clear, whitish stripe over the eyes, which is only hinted at in sparrows. The eyes of the sparrow are proportionally much larger and therefore more conspicuous than the hawk.

It is more difficult to distinguish between flying birds. The body proportions of the sparrowhawk and hawk are very similar, so it is often not possible to distinguish between gliding and sailing birds at greater distances. With reasonably good visibility conditions, however, the much more massive body and proportionally longer wings of the hawk can also be seen in flight. In the case of actively flying individuals, the frequency of the flapping of their wings can often be used to determine the species: this is about twice as high in the sparrow as in the goshawk.

Utterances

Video: Sitting and bathing sparrowhawks

Compared to other representatives of the genus, sparrowhawks call only rarely and only in the breeding area. In the event of a malfunction, a short, quickly lined up "ki-ki-ki-ki" sounds. Contact calls between the breeding birds, for example when handing over their prey, sound like “kik… kik… kik”. Both calls are not very noticeable and can only be heard from a distance of about 50 m. Most noticeable in comparison are the begging calls of the young birds that have flown out, they sound similar to the young hawks such as "kiäh-kiäh", but are higher and much less powerful and far-reaching.

Distribution of the sparrow:
  • Breeding areas
  • Year-round occurrence
  • migration
  • Wintering areas

    • distribution and habitat

    The distribution of the sparrow covers large parts of the Palearctic from the Canary Islands and Ireland east to Kamchatka and Japan . He predominantly colonizes the boreal and boreomontane coniferous forests here. The occurrence of the species is limited in most of its area to the north and south by the spread of these coniferous forests. Only in Central and Western Europe as well as in the western Mediterranean area, where other small representatives of the genus Accipiter inhabiting deciduous forests are missing, does it also colonize deciduous forests of the temperate zone and the Mediterranean hard-deciduous forests. In the last few decades this raptor species has also shown a strong tendency towards urbanization and now inhabits parks, cemeteries and similar green spaces in many cities in Europe.

    Subspecies

    Six subspecies are currently recognized; four of them have only very small areas:

    • A. n. Nisus : nominate form; almost all of Europe from Ireland to the Urals , further east to Central and Eastern Siberia.
    • A. n. Nisosimilis : smooth transition between this subspecies and the nominate form; Central and Eastern Siberia; lighter and larger than nominate shape.
    • A. n. Melaschistos : Mountains in southern Central Asia to the west as far as Kashmir ; darker, more intensely drawn on the underside and significantly larger than the nominate shape.
    • A. n. Granti : Madeira and Canary Islands ; darker and considerably smaller than the nominate form.
    • A. n. Punicus : North Africa, Maghreb south to the High Atlas and Sahara Atlas ; somewhat lighter and larger than nominate shape.
    • A. n. Wolterstorffi : Corsica and Sardinia ; even darker and more densely banded on the underside than A. n. granti and just as small.

    hikes

    Depending on the geographical location, sparrowhawks are resident birds or long-distance migrants . In Europe, the tendency to move from southwest to northeast increases. The sparrowhawks of Great Britain are resident birds. Some of them from Central Europe, especially this year's sparrowhawk, move to the southwest in late summer and autumn. Central and northern Scandinavia and almost all of Russia will be completely cleared in winter . The winter quarters of the Central European migrants are in west and south-west Europe, they reach at most as far as North Africa . The sparrowhawks from Eastern and Northern Europe overwinter mainly in Central Europe, but some also migrate to Southern France and Italy . In Central Europe, emigration takes place mainly from September to November, the emigration peak is in October. The homecoming begins at the end of February and lasts until the beginning of May; most of the Central European sparrowhawks return to their breeding grounds in the course of March. The sparrowhawks of Eastern Europe and Asia overwinter in Northeast Africa, the Near and Middle East and southern Asia, depending on the latitude .

    Female sparrowhawk with domestic pigeon in the city center of Bochum
    Sparrowhawk with a captured pigeon

    Hunting style and diet

    Sparrowhawks hunt their prey - mostly small birds - in landscapes rich in cover, mostly from flight close to the ground or from high seat in a short, fast pursuit flight in the air space close to the ground, but also in all layers of vegetation up to the treetops. Natural structures such as hedges, trees and, in the settlement area, also houses are very cleverly used for a covered approach. Sparrowhawks are extremely agile when hunting; they can change the direction of flight almost at a 90 ° angle and turn 180 ° in the air almost on the spot. These maneuvers are often no longer resolvable for the human eye and are sometimes reminiscent of ricochets . Birds are often followed into bushes and hedges or into closed spaces. At classically built bird feeders for songbirds sparrow hawks have been frequently observed that flew through the feeder while hunting. More rarely, birds are hunted down from high circles in the open air space or near the ground.

    The prey is grasped with the feet (fangs) and killed, the claws are drilled into the prey until it stops moving. In conjunction with the relatively long legs, this killing method enables the sparrowhawk to use comparatively large and defensive prey.

    Sparrowhawks feed almost exclusively on small birds in their entire range. Occasionally, small mammals such as mice or bats , small reptiles and invertebrates are also preyed on. In Central Europe, males beat birds of titmouse , finch and sparrow size, up to a maximum of about the size of a blackbird ; Females can also overwhelm birds the size of a jay or, in rare cases, a wood pigeon .

    Reproduction

    A sparrowhawk in youth clothing
    Sparrow's eggs ( Toulouse Natural History Museum )

    Sparrowhawks are sexually mature in the second calendar year, i.e. around 12 months of age. During the breeding season they lead a monogamous seasonal marriage, bigamy has been proven in rare cases. Territory delimitation and courtship are very inconspicuous. The territorial behavior towards invading foreign birds consists primarily of an "expressive flight": the bird flies with slow and powerful wing beats low above the brood population. With greater excitement, this expressive flight is occasionally supplemented by an undulating flight. During courtship, both partners circling over the breeding area and then descending one after the other to land in the breeding population. The most important element of pair formation and bonding are regular prey transfers from the male to the female; Both partners call softly. The handover takes place at a handover point or in the air. Males avoid direct contact with the much larger female as far as possible; the male usually leaves the transfer point immediately before the female lands on the prey there.

    As a breeding ground, the sparrowhawk prefers dense, little thinned, 30- to 40-year-old conifer stands . In Central Europe he shows a clear preference for spruce and larch over pine . Where conifers are missing, however, the species also breeds in dense hardwood stands. In these populations, the sparrowhawk usually builds a new eyrie on side branches every year, usually near the trunk in the lower area of ​​the treetop. Territories occupied for a long time are therefore noticeable due to the larger number of older nests. However, there are also cases in which clumps from the previous year are used again or nests of pigeons are removed and then used. In dense stands of trees, the eyrie is almost always near a small aisle , a path or a stream.

    Sparrow nests in the nest. The nest is made entirely of larch branches , note the lack of greenery.

    Nest building begins in Central Europe in mid-March at the earliest, but usually not until the beginning of April. The nest is built from dry, bare branches and not covered with greenery. It is relatively flat, the average diameter is about 60 cm, the average height about 20 cm. The nest hollow is laid out with pieces of bark. Laying begins in Central Europe in mid-April at the earliest, mostly in early May. The occupied eyrie is usually heavily afflicted with downs . The clutch usually consists of 4–6 eggs (extremes 1–7 eggs). The eggs are quite round, measure about 39 × 32 mm on average and weigh about 23 g on average. On a white background, they are more or less extensively spotted with brownish spots.

    The incubation period is 33–35 days. During the breeding and first nestling period, the male alone supplies the female and later also the nestlings with food. The female breeds almost exclusively alone and moults the flywheels and control feathers during this time. The young birds are fed almost exclusively by the female. As a rule, the plucking and handover area of ​​the district pair is within a radius of 50 meters from the nest. Due to the large number of prey birds plucked there, this place is usually much more conspicuous than the nest itself. The young stay in the nest for about 30 days, but can leave as early as 25 days in the event of disturbances. The young stay in the vicinity of the nest for another 2-3 weeks and are fed by their parents.

    Young and breeding adult birds are often preyed on by hawks , but more rarely breeding losses occur due to pine marten or the tawny owl .

    Population development and endangerment

    From the middle of the 19th century at the latest, sparrowhawks were persecuted intensively as " small game pests" and to protect the "dear" songbirds . Up until the beginning of the 20th century, even large bird protection associations such as the German Association for Bird Protection at that time paid shooting premiums . However, the stock was never seriously threatened by direct persecution; losses were quickly offset by the high level of reproduction. From around 1955, however, the populations in Western and Central Europe collapsed on a large scale due to poisoning with the pesticide dichlorodiphenyltrichloroethane (DDT). DDT accumulates strongly in the food chain (e.g. insects - songbirds - sparrowhawks) and led to a massive impairment of reproduction in the sparrowhawk, as in other bird of prey species. Direct poisoning also played a role, especially with dieldrin, which is also used as a pesticide . The sharpest decline in the population occurred in the intensively agriculturally used lowlands, where the sparrowhawk disappeared as a breeding bird on a large scale after 1955.

    With the gradual ban on the application of DDT in Western Europe from 1972 onwards, the stocks there recovered. In the GDR , DDT was still used extensively until the mid-1980s, here the sparrowhawk population increased significantly even after the year 2000. At the end of the 1990s there was no longer any evidence of impairment of reproduction due to DDT in East Germany either; however, the DDT or DDE contamination of sparrow eggs from Brandenburg was still almost three times as high in the late 1990s as that of sparrow eggs from North Rhine-Westphalia. Overall, the species is no longer endangered in Central Europe today.

    sources

    Individual evidence

    1. ↑ Karl Otto Sauerbeck: 'Herr Heinrich sat at the Vogelherd'. Observations on medieval bird hunting and its symbolism. In: Specialized prose research - Crossing borders. Volume 10, 2014, pp. 57–79, here: p. 74 ("Sparrow-eating small bird of prey").
    2. ^ "Sperber", in: Wolfgang Pfeifer et al .: Etymological dictionary of German . Digitized version in the digital dictionary of the German language, revised by Wolfgang Pfeifer . 1993 ( article on the Lemma online [accessed on 23 August 2021]).
    3. ↑ Sparrowhawk. In: Jacob Grimm , Wilhelm Grimm (Hrsg.): German dictionary . tape 16 : Sea life - speaking - (X, 1st section). S. Hirzel, Leipzig 1905, Sp. 2158 ( woerterbuchnetz.de ).
    4. ^ A b Lars Svensson, Peter J. Grant, Killian Mullarney, Dan Zetterström: Der neue Kosmos Vogelführer . Franckh-Kosmos Verlag, Stuttgart 1999, ISBN 3-440-07720-9 , p. 92.
    5. ↑ Urs N. Glutz von Blotzheim , KM Bauer: Handbuch der Vögel Mitteleuropas . Volume 4: Falconiformes. AULA-Verlag, Wiesbaden 1993/2001, ISBN 3-923527-00-4 , p. 416.
    6. ↑ Sparhawk voice example
    7. ^ E. Denker, A. Büthe, H. Knüwer, T. Langgemach, P. Lepom, I. Rühling: Comparison of the pollution in eggs of the sparrow (Accipiter nisus) from Brandenburg and North Rhine-Westphalia, Germany. In: Journal of Ornithology. 142; 2001, ISSN  0021-8375 , pp. 49-62.

    literature

    Web links

    Commons : Sparrowhawk  - Collection of images, videos and audio files