- Clements, J. F., T. S. Schulenberg, M. J. Iliff, B.L. Sullivan, C. L. Wood, and D. Roberson. 2012. The eBird/Clements checklist of birds of the world: Version 6.7. Downloaded from http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist
Falco punctatus, also known as the Mauritius Kestrel, are unique to the island of Mauritius, a small island off the coast of Madagascar. They have also been found in the neighboring Mascarene Islands.
Biogeographic Regions: indian ocean (Native )
F. punctatus are small brown falcons with short wings and long tails. Mauritius Kestrels have black eyes and tapered wings, with patches of different shades of brown. The underside plumage is predominantly white interrupted with occasional dark-brown speckles. Their talons are small and delicate. This species of kestrel is more sexually dimorphic in size than other kestrels. (Temple, 1987)
Range mass: 200 to 250 g.
Habitat and Ecology
Mauritius Kestrels originally were found in the tropical forests of the Black River Gorges but, with rapid habitat depletion, they have been introduced to and have adapted to the rocky forests and adjacent scrubby areas of the Bambous Mountains and on Moka Mountain. (Collar, 1994)
Terrestrial Biomes: forest ; rainforest ; scrub forest
Their diet primarily consists of arboreal geckos that are captured through a specialized hunting behavior known as "sun-oriented attacks". This predator also eats small birds, small rodents and insectivores, and various insects. The types of prey consumed by each sex may differ. (Temple, 1987)
Life History and Behavior
Mauritius Kestrels are monogamous during the breeding cycle. They nest in forest trees, but recently nestboxes have been introduced. The clutch size averages four to five eggs. The eggs are speckled brown oval-shaped eggs. The incubation period is 28 to 35 days, and the young are cared for in the nest for as long as 35 days. Clutches are usually laid during the months of November and December. (Village, 1990)
Date Listed: 06/02/1970
Lead Region: Foreign (Region 10)
Where Listed: Entire
Population location: Entire
Listing status: E
For most current information and documents related to the conservation status and management of Falco punctatus , see its USFWS Species Profile
IUCN Red List Assessment
Red List Category
Red List Criteria
At one point in the 1970's, the Mauritius Kestrels were the most endangered bird of prey in the world with a reported four surviving birds in the wild. It is still the rarest falcon in the world. They were officially declared an endangered species in 1973. Since then, an intense conservation and captive breeding program was created by the Wildlife Preservation Trust in collaboration with the Mauritius government. This program consists of feeding of wild birds, providing nestboxes, multiple clutching, egg pulling, artificial incubation, hand rearing and release of captive-bred and captive-reared birds by hacking, fostering, and predator control. These captive-bred birds have been successfully introduced to non-native habitats. Due to its outstanding successes, the release program ended in 1994, but conservationists have been consistently monitoring this area in hopes to reach the carrying capacity of the island, estimated to be 500-600 kestrels. (Jones, 1994)
The main problems that this species have dealt with, and are still dealing with, is habitat destruction and unregulated use of pesticides in the 1950's and 1960's. Due to deforestation beginning since 1756 under colonial French control only 3% of this island has indigenous tropical forest. This is the native habitat of the kestrels. The other problem has been the unregulated use of pesticides known as organochlorines for malaria control and in food crop production. With the addition of these pesticides to the ecosystem, they poisoned the natural food supply of the Mauritius Kestrel.
US Federal List: endangered
IUCN Red List of Threatened Species: vulnerable
CITES Appendix I and II. A recovery programme, at first concentrating on research, was initiated in 197313. From 1984 to 1994, an intensive management programme significantly increased population numbers. Activities included captive propagation and restocking, supplementary feeding, nest-site enhancement, provision of nest boxes, nest guarding, control of predators around nest- and release-sites, clutch manipulations, brood manipulations, treatment of parasite infestations on chicks and the rescue of eggs/young from failing nests8. In the late 1980s, the species was re-introduced into the Bambous mountain range by release of captive-reared birds, and subsequent evidence suggests that there was no discernable difference between the survival rate of these birds and those bred in the wild13. Since 1994, there has been no release of captive-bred birds6 and little active conservation management7, although provision of nest-boxes and monitoring of survival and productivity continue14. A few pairs still receive supplementary food to enable detailed behavioural studies and for public relations purposes8. Research is ongoing into genetic variation so that populations can be managed to preserve genetic diversity4,7,11. In October 2005, it was announced that plans for the construction of a highway through the east coast mountains' Important Bird Area of Mauritius had been cancelled, with a different route to be used15. The construction of the highway would have damaged the south-eastern forest, home to about half the species's world population, centred around Ferney Valley, which is now to become a nature reserve15. Conservation Actions Proposed
Continue detailed population and ecological studies8, particularly using molecular techniques to monitor population size11. Eventually, consider translocating birds to islands such as Réunion, although not until the endangered reptile populations on those islands are secure elsewhere8.
The Mauritius Kestrel (Falco punctatus) is a bird of prey from the family Falconidae endemic to the forests of Mauritius, where it is restricted to the southwestern plateau's forests, cliffs, and ravines. It is the most distinct of the Indian Ocean kestrels. It colonized its island home to evolve into a distinct species probably during the Gelasian (Late Pliocene). It is the most distant living species among the western Indian Ocean kestrels (Groombridge et al. 2002, qv Réunion Kestrel).
It can reach a size between 26 and 30.5 cm. The weight is up to 250 grams. The males are slightly smaller than the females. Wingspan is approximately 45 cm and wings are rounded, unlike those of other falcons. The lifespan is 15 years in captivity. The Mauritius Kestrel hunts by means of short, swift flights through forests. It is carnivorous, eating geckos, dragonflies, cicadas, cockroaches, crickets, and small birds.
The story of this bird is one of the most remarkable conservation stories. In pre-colonial time the population was estimated between 175 and 325 breeding pairs. This small population was caused most likely by deforestation in the 18th century and by cyclones. But the most severe decline was in the 1950s and 1960s due to indiscriminate DDT use and invasive species like cats, mongooses and Crab-eating Macaques which killed the kestrels and their eggs. What was probably this species' closest relative in recent times, the Réunion Kestrel, became extinct around 1700 for fairly mysterious reasons.
The recorded population dropped to an all-time low of only 4 individuals in 1974 and it was considered the rarest bird in the world. Stanley Temple from Cornell University studied this species for two years and the first attempt in 1973 to breed the birds in captivity failed because the hatchling died when the incubator had a breakdown. Though conservation measures were immediately undertaken with the help of a breeding program by the Jersey Zoo (now Durrell Wildlife Park), the efforts to rescue this species initially failed because the eggs were not fertile.
In 1979 a new attempt was undertaken. With the help of Gerald Durrell, the Welsh biologist Carl G. Jones established a wildlife sanctuary on Ile aux Aigrettes. He climbed on the trees and removed the eggs from the nests. This time the eggs were fertile, and Jones was able to rear the hatchlings in incubators. The wild kestrels' diet was supplemented so they would be able to lay a new egg after the first one was removed, averting any negative impact on the wild population. Slowly the population increased and during a census in 1984 50 individuals were estimated. Techniques for breeding, release, and "hacking" of young birds were improved, the captive breeding center becoming a pioneering research institution for tropical raptor and small falcon conservation. The captive breeding programme was scaled back in the early 1990s as a self-sustaining population was established. Since 1994, the programme serves only as a safeguard, should some catastrophe befall the wild population, and other rare endemics are now being cared for at the station (such as the Pink Pigeon or the Mauritius Fody).
Today there are more than 800 mature birds, with numbers rising; it is estimated that the remaining habitat allows for a carrying capacity of maybe 50-150 more (BirdLife International 2006a,b). They occur in the remaining forests of the island, especially in the Black River Gorges region. The species was downlisted to Vulnerable by the IUCN in 1994 as releases of captive-bred birds became unnecessary. Little conservation action was deemed necessary only two decades - in Mauritius Kestrel terms, a long lifetime or maybe 4-5 generations - after the species had stood at the very brink of extinction. Today, apart from routine monitoring to be able to assist individual couples that fail to establish breeding territories for lack of nesting facilities - a major limiting factor, the ongoing control of introduced predators is basically all that is being done to assist the species' survival (BirdLife International 2006a,b).
While some apparent inbreeding depression was noted in the captive birds, it was certainly lower than might be expected given that the effective population size was maybe 5 individuals during the mid-1970s. It is known that several genetic lineages of Mauritius Kestrels have disappeared entirely during the 20th century population decline. However, the debilitating effects of DDT accumulation on the birds' health, and not inbreeding, are considered to have been the major cause for the failure of Temple's breeding program.
The evolutionary history of the birds seems to hold clues as to why (Groombridge et al. 2002): Mauritius is a volcanic island, and although the colonization of the island by kestrels cannot be dated with high precision, it was almost certainly some time before volcanic activity died down. The Mauritius Kestrel population seems to have survived a prolonged period of volcanic activity, which must have kept the population small and fluctuating as habitat, food, and kestrels were destroyed by volcanic eruptions time and again. As near-panmictic conditions were sustained for many generations, alleles that might cause inbreeding depression were steadily removed by means of natural selection. The phenomenon that effective population sizes as low as 4-5 can be tolerated without pronounced inbreeding depression is also known from other small-island birds, such as Petroica traversi or the Laysan Duck.
The classification as a Vulnerable species is due to the same fact: on an island as small as Mauritius, chance events like volcanic eruptions (hardly likely in our time) or storms (common and possibly increasing in frequency and strength) can always wipe out major parts of a species' population (BirdLife International 2006a,b). The IUCN classification VU D1+D2 reflects this, translating into a population size of less than 1000 mature individuals, and less than 20 km² of occupied habitat.
- BirdLife International (2006b): Mauritius Kestrel - BirdLife Species Factsheet. Retrieved 2007-MAR-1.
- Diamond, Anthony W.& Roger Tory Peterson Institute (RTPI) (1989): Save the Birds. Houghton Mifflin, Boston. ISBN 0-395-51172-0
- Erritzoe, Johannes & Erritzoe, Helga (1993): The Birds of CITES and How to Identify Them. Lutterworth Press. ISBN 0-7188-2895-X
- Ferguson-Lees, James & Christie, David A. (2001): Raptors of the World. Houghton Mifflin, Boston. ISBN 0-618-12762-3
- Groombridge, Jim J.; Jones, Carl G.; Bayes, Michelle K.; van Zyl, Anthony J.; Carrillo, José; Nichols, Richard A. & Bruford, Michael W. (2002): A molecular phylogeny of African kestrels with reference to divergence across the Indian Ocean. Molecular Phylogenetics and Evolution 25(2): 267–277. doi:10.1016/S1055-7903(02)00254-3 (HTML abstract)
- Staub, France (1976): Birds of the Mascarenes and Saint Brandon
- BirdLife International (2012). "Falco punctatus". IUCN Red List of Threatened Species. Version 2012.1. International Union for Conservation of Nature. http://www.iucnredlist.org/apps/redlist/details/106003592. Retrieved 16 July 2012.
- Ellis, Richard (2004). No Turning Back: The Life and Death of Animal Species. New York: Harper Perennial. p. 279. ISBN 0-06-055804-0.
- Possibly to be moved to the Early Pleistocene. See Groombridge et al. (2002) for a thorough discussion of this species' recent evolutionary history.