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The falcon species has always been regarded as a very uncommon and shy bird, and it is very rarely met with by amateur birdwatchers (Ali 1968). Falcon is the national bird of UAE and is a symbol of force and courage, recognizing the importance of falconry in Arab tradition and culture. Arabs constitute 1/3rd part of the world’s falconers. Falcons are fast flying hunters suited for taking prey in the air. In this pesticide era they are facing serious ecological risks, as their position is at the top of the biological pyramids.
The falcons are extremely accomplished and swift fliers generally killing their prey on the wing (Ali 1967). The most important activity of falcons is hunting (Baker 1967). Some species of falcons are extensively used in the sport of falconry (Ali 1983). Unlike many birds, falcons live as single pairs within the community (Ratcliffe 1980). The documented speed of a Peregrine’s stoop is over 320 km/hr (Cade 1980). Peregrine falcons generally mate for life, but will readily accept a new partner if their mate dies (Newton 1990). Food requirements vary depending on a bird's age, size, activity and season (Thorstrom 2000). Riddle and Remple (1994) estimated that there might be 8600 Saker and Peregrine falcons in captivity in the Middle East. A lot of works and studies have been conducted across the world, from time immemorial to the present, regarding falcons and falconry. Eminent writers and bird watchers have contributed memorable and informative works on this subject.
My study was to examine behaviours like vocalization and timing of movement by field observation in and around the aviaries, cages and flight pens of various centres. Vocalization helps falcons to communicate with each other. The main objectives of this study were to document the information that relates to the biology, behaviour and captive management of falcons. The prime focus of the study was in captivity. Field observations were also made especially with reference to hunting behaviour, training and other related aspects. Data relevant to feeding, breeding, health and healthcare, management in captivity were collected. Data on roosting, bathing, foraging and vocalization, and different types of food, feeding methods and food consumption in captivity and in the field were also collected.
The other objectives of the study were to examine the environmental requirements at different stages of breeding, to observe and acquire knowledge of pterylographic and taxonomic patterns of feathers on body tracts of adults and nestlings and to observe and document the sequence of moulting and plumage. An attempt is also made to document various species of falcons used for falconry in UAE, methods of hunting and training practices, the reasons for falcon's extinction and their remedies and falconry through ages and its current state.
The present study on the biology of falcons was carried out in different parts of UAE, mainly because of their large number in captivity. The study was started in November 1999, and pursued more intensively from August 2001 till December 2003. The study was conducted in falcon breeding and research centres, falcon hospitals and falcon clinics, concentrating in H.H. Sheikh Zayed Ibnu Sultan Al Nahyan Falcon Research Hospital, Abu Dhabi; Environmental Research and Wildlife Development Agency (ERWDA), Abu Dhabi; National Avian Research Centre (NARC), Sweihan; Nad Al Shiba Avian Reproduction Research Centre, Dubai; Dubai Falcon Hospital; and Falcon Clinic, Sharjah.
The falcon cages were monitored through spy holes during breeding season. Through lab test results of fecal samples and pharyngeal swabs, an attempt was made to find disease-causing organisms. For observations on various behavioural aspects, standard methods were adopted. Eggs were measured and weighed by Brunham formula. Falcons were closely followed to maximum possible period through their fledgling, juvenile, one-year-old and adult at different ages. Colour rings were used to make individual recognition possible in cages. Feathers were plucked and patterns of follicle arrangements were observed for pterylographic study as adopted by Naik (1965). Moult of feathers was studied by measuring various feathers of the individual primaries, secondaries and tail feathers of 40 birds of Peregrine, 20 each of Saker and Gyr falcons by using the scoring system adopted by Miller (1928). Formalin preserved specimens were washed thoroughly in water for many hours and dried.
The weather plays a major role in connection with the hunting and abundance of preys. The climate in UAE is hot and rainfall is low. Falcons are very sensitive to climatic conditions and fastest in the animal kingdom. They have special characters some of which are mentioned below. Having twice the number of cervical vertebrae enables them to rotate their heads on the axis to almost 360 degrees. Falcons have two regions of retina for acute vision. Nostrils have needle like projection for cutting air and easy flight.
It was observed that all falcons of the area were early raisers, made morning calls and moved out of roosts, preened feathers, moved from one roost to another and glided down to start foraging. In aviaries and pens small boxes were provided for roosting. It was noticed that falcons foraged in morning twilight but not in evening. They drank water many times in summer.
The falcon is a very aggressive and busy bird. Unlike most other birds, females are larger than males. It is observed that a hungry falcon will attack even other falcons in aviary for food. Their body is well adapted for attacking and capturing prey. They have specific timings for each activity like roosting and sleeping. In captivity they keep themselves busy by moving from one roost to another. Falcons are migratory birds from breeding grounds to wintering grounds and back.
Falcons are carnivorous and sensitive to stored food during breeding. There are several species of falcons, but in UAE three major species are used for falconry. They are Peregrine, Saker and Gyr. Peregrine is widely spread all over the world except Antarctica. Saker flies fast and hunts at low level. Gyr is powerful and prefers to catch larger preys. Birds, large insects, rodents and other small ground animals are the main food. It is found that larger falcons have a tendency to hunt bigger preys than smaller ones. It is observed that the majority of food items were sand grouse (31.3%), stone curlew (24.8%), houbara bustard (13.5%) and desert hare (10.3%). They also consumed rat, pigeon, lizard, quail, etc.
The consumption of only live food may cause diseases; so mixed food (frozen and live) is advisable for proper health. If they feed on boneless meat regularly, calcium deficiency occurs and affects bones, beak, claws etc. and casting does not occur properly. The boned and boneless mixed food is suggested to take care of calcium deficiency and casting. It is noticed that falcon's digestive system can dissolve bones. Although fresh food is best for them, sometimes frozen food is unavoidable. Falcons are fed with live or frozen food in hunting season, but in moulting period they are given frozen food. Fasting once fortnightly is recommended for proper casting. It is advisable to spray water on facial and thoracic regions of falcons, speed up defecation.
As falcons are royal birds, breeding and management are expensive. The objectives adopted were to examine the environmental requirements and different stages of breeding. In UAE the breeding season starts from February-March to August-September. Most falcons are monogamous and they have unique breeding cycle. They breed once a year and live with the same mate until death.
Through artificial insemination, the breeding centres have helped the falcons overcome the decrease in population. During artificial semen collection urine contamination may occur, and is solved by seminal washing. DNA testing and laproscopy are used to determine sex. Falcon's life span is as high as 10 to 12 years, but captive falcons live longer. In Peregrines and large falcons males apparently reach sexual maturity on an average, about a year later than females.
It is observed that if first eggs are damaged before hatching or chicks die in first few days, they lay more than one clutch of eggs in a year. Mortality rate is constant with respect to age unlike other animals. The larger species reach breeding age at 2-3 years. The eggs of Peregrine are creamy pink to reddish-brown and are average of 53mm. long. It is observed that overall mean clutch-size recorded was 3.3. Generally 2-6 eggs are laid, incubation is 28-35 days, offspring fledged in 4-8 weeks and youngs stay with parents learning to hunt for 1-3 months. Average incubation period was 32.6 days. Details of fate of eggs laid by Peregrines were as: 57% hatched, 24% did not hatch even after extended incubation, 11% were damaged during incubation and 8% destroyed by the effect of pesticides. First two eggs hatched after an interval of 2.31 days on an average. Since incubation started with laying of first egg, eggs in a clutch hatched asynchronously. Average nestling and fledgling periods were 16.6 and 37.1 days respectively.
It was noticed that even though differences in size, there is no significant difference in the daily food intake of male and female nestlings for about the first 21 days. It is understood that female nestlings require a greater amount of food than do males, but because of greater growth efficiency, they need less than expected on the basis of body mass.
Pterylographic studies, study of plumage and moulting of falcons are indispensable features for research studies. The less availability and high cost make the falcons difficult to get for studies like this. The study is meant to acquire the maximum knowledge of taxonomic pterylographic patterns of feathers on body tracts of adults and nestlings. Falcons generally moult once a year. The moulting time is the resting period of falcons in captivity.
Pterylosis of young differs in some pterylae from that of the adults. The femoral tract in nestlings is not developed as in adults. It is noticed that after moulting, in the second year the colour of moulted feathers in wild falcons differ compared to falcons in captivity. The probable reason may be differences in nutrition. The colour of secondary feathers got changed in Peregrine and Gyr after two years of age, but the primary feathers will be same. It was observed; the relationship of plumage colouration was more or less not influenced in pairing. The season for moulting in all falcons coincides with breeding season. At the population level falcons moult primaries from March to October, secondaries April to November and retrices May to November. In the case of Peregrine falcons the moulting starts very late, from May and it lasts till next January.
The management of falcons in captivity requires highly sophisticated facilities. Temperature and humidity controllers are to be provided in captivity. Aviaries should be well lit and airy and faced away from cold prevailing winds. Nest ledges or boxes are to be placed in aviaries. In aviaries roofing materials are to be used with the purpose of preventing excess heat in summer and condensation in winter. In falcon aviaries the wet muddy substrate is a cause of hypothermia and poor perches is the reason of bumble foot disease. Falcons only breed in captivity when they feel convenience and comfortability. It is advised to leave alone enclosures from disturbance from egg laying to youngs have fledged.
In captivity food is not given to falcons in live condition and it can be advised that frozen food items are not to be given below 20°C. It is also recommended that food ledges are to be used for feeding falcons in captivity. Calcium supplements and vitamins are given if necessary. Youngs require more food than adults. In falcons dehydration is widely seen, so in captivity drinking water and bathtubs are to be erected.
In captivity management of falcons may not be perfect without caring the health and hygiene. Hence the topic health and healthcare was included in my studies. This includes documenting important preventive, promotive and curative measures taken in falcon hospitals and clinics for various diseases. Main objectives of study were to document the diseases caused by virus, bacteria, fungus, internal and external parasites and diseases by other agents and their preventive measures.
A large variety of viral, bacterial and fungal diseases are widely seen in falcons. Most diseases are not so critical if precautions and treatments are taken in proper time. Bacterial infections are not so dangerous as viral diseases in falcons. Most bacterial diseases and viral diseases are transmitted to falcons through their preys like pigeons. The endoparasites are protozoans and helminths. The study based on statistical field research showed that in captivity bumblefoot is seen widely, so it is advised to give the falcon training twice a day to reduce the morbidity rate.
As far as falcons are concerned the diseases are not fatal, except New Castle and Aspergillosis in late stages. Proper management, routine checkup, health awareness programmes and counseling will prevent almost all diseases.
Falconry is the traditional sport of the Arabian Gulf. Arab people constitute one-third of the total falconers in the world. Major species used for falconry comprises of Peregrine, saker, Gyr and their hybrids.
Skilled trainers train falcons to perfect the techniques of hunting. Today falconry is facing a serious threat by habitat destruction, pesticides and diseases. Falcon trappers catch them when they rest on the route during migration. Though falcon population faces serious threats, man has made modern technological improvements to reduce the rate of destruction through captive breeding and falcon release project. Proper management, better hygiene, balanced diet and routine checkup will prevent almost all diseases to a certain extent.
The following recommendations are given:
- Since consumption of live specimens cause infectious parasitic diseases. A mixed food regime of frozen and live food is advisable. Feeding on stored food alone is not healthy and food frozen below 20oC may be avoided. Food supplements are necessary if the birds are fed on monotype food. Diverse food promotes healing wounds, immunity, hunting capacity, and proper casting.
- Fasting once in a fortnight facilitate proper casting. Ammonium chloride, used for purgation of falcon's alimentary system, kills them when given excessively.
- Old food items are to be removed from the cages regularly. The food items should be given in food ledges or in a clean place. Throwing food to falcons is not advisable.
- Food items should be checked before feeding to falcons. Attempts should be made to reduce the possibility of infected pigeons transferring trichomoniasis to falcons. Falconers should feed the falcons only after removing head, neck and internal organs of preys. Pigeon flocks should be medicated with antiprotozoal drugs to reduce the number of protozoan carriers.
- For artificial insemination the spermatozoa may be washed gently using water, immediately after collection, to clean it off the urine and other contaminations. Contaminations are likely to cause lower success.
- In aviaries roofing materials are to be used with the purpose of preventing excess heat in summer and condensation in winter.
- Falcons constantly forced to land on cold muddy floors are likely to have health problems and hypothermia. Bark or wood clips are not suitable substrate as they harbour spores of Aspergillus sp.
- It is advisable to change perches regularly. Changing the perches once in a while gives a stimulus to the raptors. Apart from perches, baths, feed ledges and hidden retreats are also necessary in the enclosures. Poor perches in aviaries are known to cause over 80% of the bumble foot disease. The talons should be cut and trimmed once a month especially during moulting season, otherwise it may cause bumble foot.
- Best time to remake nests and clean the cages and nest boxes is 6-8 weeks before the breeding season. Once egg laying commences it is best to leave enclosures undisturbed until hatching.
- The bathtubs of 4-6 inches of water depending on size and height of the individual falcons are deep enough for most birds for bathing. Bath water is not necessary for sick birds, although water for drinking must be available. Cleaning the bath at least twice a week especially during summer is necessary to avoid green algae and other noxious materials build up.
- Entering into aviaries should be with great care and feeding done carefully if pairs are showing behavior associated with breeding. It is better not to enter the cage until chicks are full fledged.
- Effective windshields are advisable to protect the birds during moulting season to speed up the moulting.
- Some of the diseases are fatal to falcons. However, proper management, better hygiene, balanced diet and routine check up will prevent to a certain extent almost all diseases affecting falcons.
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