Saker falcons (often simply called “sakers”) occur in the semi-desert and forest regions from Eastern Europe to central Asia, where they are the dominant “desert falcon.” Saker falcons migrate as far as northern parts of southern Asia and parts of Africa for the winter. Recently (in 1997), sakers have been observed breeding as far west as Germany. (Baumgart, 1998; Cade, 1982)
Sakers occupy stick nests in trees, about 15 to 20 meters above the ground, in parklands and open forests at the edge of the tree line. No one has ever observed a saker falcon building its own stick nest; they generally occupy abandoned nests of other bird species, and sometimes even drive owners from an occupied nest. In the more rugged areas of their range, sakers have been known to use nests on cliff ledges, about 8 to 50 meters above the base. (Anderson and Squires, 1997; Cade, 1982)
Sakers exhibit great variation in color and pattern, ranging from a fairly uniform chocolate brown color to a cream or straw base with brown bars or streaks to brown-eyed leucistic individuals, which are especially prized by Arab falconers. In general, sakers have white or pale spots on the inner webs of their tail feathers, rather than the bars of color that are common among other desert falcons. As the underwing is usually pale, it has a translucent appearance when contrasted against the dark axillaries and primary tips.
Saker females are markedly larger than males; females typically weigh 970 to 1300 g (average 1135 g), have an average length of 55 cm, and a wingspan of 120 to 130 cm. Males usually weigh from 730 to 990 grams (average 840 g), are about 45 cm long on average, and have a wingspan of 100 to 110 cm.
As with other falcons, sakers have sharp, curved talons, used primarily for grasping prey. Sakers use their powerful, hooked beak to sever the prey’s vertebral column. (Anderson and Squires, 1997; Cade, 1982)
In order to attract females, male sakers engage in spectacular aerial displays, in common with many other members of the genus Falco. Male sakers soar over their territories, calling loudly. They end their display flights by landing on or near a suitable nesting site.
In closer encounters with a mate or prospective mate, sakers bow to each other, and many interactions incorporate some element of bowing. Males also often feed their mates during the nesting period. When wooing a potential mate, a male will fly around, dangling prey from his talons, or will bring it to the female in an attempt to prove that he is a good provider. (Anderson and Squires, 1997; Cade, 1982)
Sakers are generally two to three years old before they begin breeding. There can be 2 to 6 eggs per brood, but generally the number is between 3 and 5 (on average 4). After the third egg is laid, full incubation begins, and usually lasts for about 32 to 36 days. In general, as is true for most falcons, males offspring develop faster than females.
The young hatch with their eyes closed, but they open in a few days. They have two downy nestling plumages before attaining juvenile plumage. They attain adult plumage when a little over a year old, after their first annual molt.
Females reach sexual maturity about a year before males; they occasionally breed in their first year, but usually not until their second or third year, and some wait until their fourth year. Males, on the other hand, begin breeding in their second year at the very earliest; most wait until the third or fourth year, and some males don’t begin breeding until their fifth year. (Anderson and Squires, 1997; Cade, 1982)
Young sakers begin to fly at about 45 to 50 days of age, but remain within the nesting territory, dependent on their parents for food, for another 30 to 45 days, and occasionally longer. If they encounter a large localized source of food, brood mates may remain together for some time.
While still in the nest, chicks chirps to get a parent’s attention if they are isolated, cold, or hungry. In addition, females may make a soft “chip” noise to prompt their young to open their beaks to receive food. Mothers will pass over a chick that is begging but has a full crop in order to feed a chick that has not eaten enough. When a brood is well-fed, the chicks get along better than in a brood subject to food scarcity. In a well-fed brood, the chicks share food as well as explore with each other once they begin to fly. In contrast, when food is scarce, chicks guard their food from one another, and may even try to steal food from their parents. If a chick dies and the rest of the brood is hungry, they will eat their dead sibling, but fratricide has never been observed. (Anderson and Squires, 1997; Cade, 1982)
Falcons used for hunting are still subject to many of the same causes of mortality as those in the wild, including several bacterial and viral diseases, parasites, bumblefoot disease, lead and ammonium chloride poisoning, and injuries incurred from impacting or struggling with prey, to name a few.
Although most wild individuals are expected to live from 5 to 7 years, a few of these birds have been known to live for as long as 10 years. Captive animals tend to live longer than their wild counterparts. In captivity, sakers are expected to live from 15 to 20 years, but may reach a maximum age of about 25 years. (Naldo and Samour, 2004)
Sakers are very aggressive; one of the reasons they are so prized by falconers is that once they have decided upon a target prey, they are very persistent. They have been known to follow their prey into brush, and in the past (in the Middle East) they were used to harry and attack large game, such as gazelle, until the saluki hounds could catch up and finish the animal off. Sakers are patient, relentless hunters. They hover in the air or sit on their perch for hours watching for prey and fixing the exact location of their target, until suddenly diving for the kill. Females are almost always dominant over males. They sometimes try to steal prey from each other. (Cade, 1982)
Sakers are not social birds; they prefer not to establish their nests close to other nesting pairs. Unfortunately, due to habitat destruction, sakers are being forced to nest closer and closer together, much more so than they ever would otherwise. However, in areas where food is plentiful, sakers will nest closer together than in areas where food is scarce. Space between pairs ranges from three to four pairs in three acres to pairs being six miles or more apart in the mountainous areas and steppes. The average spacing is one pair every 2.5 to 3.5 miles. (Cade, 1982)
As mentioned before, a female saker will make a “chip” noise to prompt her young to open their beaks for food, and they will chirp to get a parent’s attention. Male sakers call during their aerial displays in order to attract or impress a female, and if the female accepts the male, she may join in the calling at the end. Sakers may often call aggressively to drive off intruders from the nest or a freshly killed meal.
Sakers, like other falcons, communicate fairly often by posturing. The most aggressive display is the Upright Threat; the bird stands up straight, spreads its wings and fluffs out its facial feathers, hisses, cackles, and strikes with the feet. This display is used by adult falcons in defense of the young, and by feathered nestlings against nest intruders. Sakers also use bowing to appease a mate, and communicate submission with a modified version of bowing, in which the beak is pointed to the side. (Cade, 1982)
During the breeding season, small mammals such as ground squirrels, hamsters, jerboas, gerbils, hares, and pikas may constitute 60 to 90% of a saker pair’s diet. At other times, ground-dwelling birds such as quail, sandgrouse, pheasants, and more aerial birds such as ducks, herons, and even other raptors (owls, kestrels, and harriers) can account for 30 to 50% of all prey, especially in more forested areas. Sakers may also eat large lizards. (Anderson and Squires, 1997; Cade, 1982)
Sakers have no known predators in the wild, except humans. (Cade, 1982)
Sakers are a favorite of Arab falconers. (Cade, 1982)
As with all falcons, sakers may prey upon species (such as pigeons) that humans value. They are not well liked by gamekeepers. (Cade, 1982)
The fact that female sakers, being larger, are preferred by falconers has led to a gender imbalance in wild populations, with males outnumbering females. In fact, about 90 percent of the almost 2,000 falcons trapped each year during the fall migration are females. These numbers cannot be reported with absolute certainty, because some sakers are illegally trapped and exported, especially in Mongolia, so it is impossible to know the true number of sakers taken from the wild each year. Juveniles are easier to train than adults, so most of the trapped sakers are around one year old. In addition, in the Middle East many falconers release their sakers because it is difficult to care for them during the hot summer months, and many trained birds escape. Basically, the number of sakers taken each year probably does not have a significant impact on the species, but the preference for female sakers does. In addition, sakers are affected by the use of pesticides (which contaminate their prey) and destruction of their habitat. A fairly recent estimate of the saker population in the wild is from 1982, when the population stood at about 100,000 pairs. That does not include juveniles, captive birds that may have later been released back into the wild, or pairs that ornithologists may have missed, so the estimate is probably on the low side. However, saker falcons an endangered. (Anderson and Squires, 1997; Batdelgar and Parrot, 1998; Cade, 1982)
Victoria Hekman (author), Michigan State University, Pamela Rasmussen (editor, instructor), Michigan State University, Nancy Shefferly (editor), Animal Diversity Web.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
uses sound to communicate
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
makes seasonal movements between breeding and wintering grounds
Having one mate at a time.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the business of buying and selling animals for people to keep in their homes as pets.
scrub forests develop in areas that experience dry seasons.
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
places a food item in a special place to be eaten later. Also called "hoarding"
uses touch to communicate
Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
A terrestrial biome with low, shrubby or mat-like vegetation found at extremely high latitudes or elevations, near the limit of plant growth. Soils usually subject to permafrost. Plant diversity is typically low and the growing season is short.
uses sight to communicate
Anderson, S., J. Squires. 1997. The Praire Falcon (Section 3-Prairie Falcons and Other Raptors). Austin: University of Texas Press.
Batdelgar, D., A. Parrot. 1998. The Illegal Export of Saker Falcons (Falco cherrug) in Mongolia. 5th World Conference on Birds of Prey and Owls: 64.
Baumgart, W. 1998. New Developments on the Western Border of the Saker falcon (Falco cherrug) range in Middle Europe. 5th World Conference on Birds of Prey and Owls: 17-18.
Cade, T. 1982. The Falcons of the World. London: Cornell University Press.
Naldo, J., J. Samour. 2004. Causes of Morbidity and Mortality in Falcons in Saudi Arabia. Journal of Avian Medicine and Surgery, 18/4: 229-241. Accessed April 22, 2005 at http://www.bioone.org/bioone/?request=get-document&issn=1082-6742&volume=018&issue=04&page=0229.