Justification of Red List Category
This species has seen a steady and prolonged increase in the wild population as a result of intensive recovery management. However, its overall numbers are still small, and the population is restricted to a small range within which habitat continues to decline. It therefore qualifies as Endangered.
At the end of the 2011/2012 breeding season the population was estimated at c580 birds, which was conservatively estimated to include 300-350 mature individuals (V. Tatayah in litt. 2012).
The population is estimated to have experienced an extremely rapid increase over the last 23 years (three generations). The population increased from <50 birds in 2000 to 280-300 in 2005 (C. Jones in litt. 2005), and the 2004-2005, 2005-2006 and 2006-2007 breeding seasons have shown continued improvement (Raffray 2005, V. Tatayah in litt. 2006, Malham 2007). By March 2006 the population had increased to an estimated 309-335 birds, although numbers fell to an estimated 290 birds by August 2006, probably due to Psittacene Beak and Feather Disease (PBFD) (V. Tatayah in litt. 2006). Despite this, the population had increased to an estimated 343 birds in 2007 (Raffray 2007) and c.580 birds in 2011/2012 (V. Tatayah in litt. 2010).
Psittacula eques survives in south-west Mauritius, having become extinct historically on Réunion (to France). From the 1970s to the mid-1980s the 10 or so known birds appeared to suffer almost total breeding failure. However, breeding subsequently began to be successful, and in 1993-1994 there were 16-22 birds. During the 1996-1997 breeding season there were 13 known wild pairs with a total of 50-61 birds present at the end of the breeding season restricted to an area of c.50 km2 contained within the 65.74 km2 Black River Gorges National Park in the south-west of the island (Jones and Swinnerton 1997). In 1998 the wild population stood at 59-73 birds, with 14 captive-bred or captive-reared birds having been released at Macchabé-Brise Fer since 1997 (Safford 1998). The rapid increase in population since 1995 is due primarily to intensive management of the wild population, the discovery of previously unknown breeding birds and an increase in the number of breeding groups that attempt to breed each year (Thorsen and Jones 1998). In the 1999/2000 season the population stood at 106-126 wild individuals (C. Jones in litt. 2000). Since that time the population continued to increase to 55 pairs (280-300 birds in the wild) in February 2005 (C. Jones in litt. 2005, Malham 2005). The 2004-2005, 2005-2006 and 2006-2007 breeding seasons showed continued improvement (V. Tatayah in litt. 2006, Malham 2007), and in March 2006 the population was estimated at 309-335 in the wild (V. Tatayah in litt. 2006). Numbers fell to an estimated 290 birds by August 2006, probably due to Psittacine Beak and Feather Disease (PBFD) (V. Tatayah in litt. 2006), but recovered to over 500 birds in August 2010 (Jones 2010), with 129 young fledging in 2011/2012, and a known population of c.580 birds (V. Tatayah in litt. 2012). The species occupies only c.40 km2 of remnant native upland forest and uses only around 50% of this regularly (Thorsen et al. 1998).
This species now survives in forest and upland scrub (Marshall 1997), with lowland, intermediate and scrub forests being very important feeding areas (Jones 1987). It appears to be a strictly arboreal forager, feeding mainly on native plants and taking a wide range of parts including buds, young shoots, leaves, flowers, fruits, seeds, twigs and even bark and sap (Jones 1987). They return to favoured food trees, some of which have been used for generations (Jones et al. 1998). Birds forage singly or in small groups in different areas at different seasons and are known to travel several kilometers to and from feeding areas in search of food, although the dwarf forest and scrublands of the south-west plateau are an important foraging area throughout the year (Jones 1987). Nesting takes place in natural cavities in native trees (Greenwood 1996). It is monogamous, but breeding units in the 1970s and 1980s often comprised a group of one female with up to three males, one of which was dominant and mated with and fed the female (Jones et al. 1998). The presence of extra males was probably the result of a formerly skewed sex ratio; pairs are usually hostile to extra males, who seem to have no positive effect on fledging success, which is probably related to the experience of the dominant male (Jones et al. 1998). Clutch size is 1-4 (but normally 2-3) eggs, which are laid from September-December (Thorsen and Jones 1998, Jones et al. 1998), and incubation, by the female, lasts 21-25 days (Jones et al. 1998). Hatching success is high (C. Jones in litt. 2000). One or two chicks are usually fledged (Jones et al. 1998) from the end of October to the beginning of February or later, and fledgling parakeets are reputed to stay with their parents, being fed by them for at least 2-3 months after leaving the nest (Jones 1987). One possible reason for the marked increase in the number of pairs attempting to breed each year is the species's increasing utilisation of exotic plants for food, particularly the very common and invasive strawberry guava Psidium cattleianum (Jones et al. 1998, C. Jones in litt. 2000).
This species's earlier decline and contracting distribution corresponds to the severe destruction and degradation of its native habitat (Jones 1987, Greenwood 1996). The population crashed from a likely total of several thousand following forest destruction and the replacement of its favoured feeding habitat, upland dwarf forest, with plantations (Jones et al. 1998). In 1996, only 5% of the island was covered with native vegetation (Jones et al. 1998). The areas of upland native forest that remain continue to be highly degraded by cyclones, the influences of past forestry practices, the spread of introduced plants such as guava Psidium cattleianum, privet Ligustrum robustum and jamrosa Syzygium jambos and the effect of introduced feral mammals such as pigs Sus scrofa and rusa deer Rusa timorensis (Greenwood 1996, Thorsen and Jones 1998). The production of native fruit, on which the parakeet feeds, and regeneration of potential nest trees is thus poor (Greenwood 1996). Recent research suggests that food shortage due to deterioration of the native forest is the major cause of nest failure; although exotics can provide an abundant food source it is not available year-round or even throughout the breeding season (Thorsen and Jones 1998). Crab-eating macaques Macaca fascicularis and black rats Rattus rattus are amongst a number of introduced arboreal species which pose a threat to parakeets by raiding nests and competing for native fruits (Greenwood 1996). Bees Apis mellifera, yellow wasps Polistes hebraeus, paper wasps, termites, White-tailed Tropicbirds Phaethon lepturus, introduced Common Mynas Acridotheres tristis and Ring-necked Parakeets Psittacula krameri are all nest site competitors and can displace active breeding pairs (Thorsen and Jones 1998, C. Jones in litt. 2000, V. Tatayah in litt. 2012). The decline in the number of old native trees, which are lost to storm damage and senescence, has intensified competition for nesting cavities, with 14-19% of P. eques cavities lost to competitors each year (Jones et al. 1998). Infestations of nest fly larvae can be severe in some years and, without intervention, would kill many young (C. Jones in litt. 2000). PBFD has been found in over 20% of sampled birds, and at least 50% of birds observed with PBFD are believed to have died, however a number of individuals have been seen to recover from the disease (Richards 2010). Pesticides do not seem to have significantly affected the species (Greenwood 1996).
Conservation Actions Underway
The species has been the subject of a conservation programme since 1973 (Jones et al. 1998). The dramatic increase in the species's population in recent years is undoubtedly due to an intensive programme to manage the wild population combined with a highly successful captive breeding programme since the 1993/4 breeding season (Jones et al. 1998) - a collaborative effort of the Mauritian Wildlife Foundation, the World Parrot Trust, the Mauritian Government and the Jersey Wildlife Preservation Trust Society (Greenwood 1996). Between 1997 and 2004, when reintroductions were completed, a total of 139 captive reared birds were released (Jones 2010). Intensive management includes nest site enhancement, provision of nest boxes (now more used than natural nests), supplementary feeding of some individuals, predator control around nest sites, control of nest competitors (P. krameri, rats, mynahs), control of nest parasites, close guarding and monitoring of all nests, rescue of eggs/young from failing nests, clutch manipulations (double clutching, exchanging infertile eggs with fertile ones), and brood manipulations (downbrooding, ie removing extra chicks from large broods and giving to foster parents) (C. Jones in litt. 2000, Jones et al. 1998). All nest cavities are enhanced, modified and repaired as necessary, and measures taken to eliminate rats and parasites and prevent flooding (Jones et al. 1998). Habitat management has been directed at increasing the productivity of native forest and has included the foundation in 1993 of the Black River National Park in 6,574 ha of native forest (Jones and Hartley 1995, Greenwood 1996), including most of the species's remaining habitat (Jones et al. 1998). There are 14 Conservation Management Areas (CMAs), ranging from 0.2 to 24 ha, in which native forest is manually cleared of weeds (Jones et al. 1998). Some of these CMAs are heavily utilised by the species as their trees produce bumper crops (C. Jones in litt. 2000). Captive-reared birds have been released into the largest CMA, where problematic mammals are controlled (Jones et al. 1998). Research has occurred on present and historic genetic variation of the species so that the effects of the population bottleneck can be quantified and current populations managed to preserve maximum genetic diversity (Tollington et al. 2013). Research into the impact of PBFD is likely to be ongoing for several years (Malham 2007), and has involved intensive screening of birds since 2005 and several PhD studies (Richards 2010, V. Tatayah in litt. 2012). It now includes looking at whether birds which recover from the disease remain carriers and have the potential to pass it on to their offspring, and whether P. krameri may act as a reservoir for the disease (Richards 2010). Strict hygiene measures have been introduced to prevent species management spreading the disease (Richards 2010). Birds are fed supplemental food in the wild (V. Tatayah in litt. 2012).
36 cm. Long-tailed, green parakeet. Male has bright red bill. Female has dark bill and is generally darker overall. Similar spp. Easily confused with smaller, paler Rose-ringed Parakeet P. krameri and best distinguished by vocalisations. Voice Loud kaaark kaaark in flight and sharp, short kik kik, unlike the high-pitched shrieks and shrills of P. krameri.
Text account compilers
Benstead, P., Bird, J., Butchart, S., Ekstrom, J., McClellan, R., Pilgrim, J., Shutes, S., Symes, A., Taylor, J., Warren, B., Westrip, J.
Tatayah, V., Jones, C.
BirdLife International (2018) Species factsheet: Psittacula eques. Downloaded from http://www.birdlife.org on 24/06/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 24/06/2018.