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NR
 Mesophoyx intermedia

This taxon is Not Recognised as a species by BirdLife International.

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: #http://www.aerc.eu/DOCS/Bird_taxa_of _the_WP15.xls#.
Christidis, L.; Boles, W. E. 2008. Systematics and taxonomy of Australian birds. CSIRO Publishing, Collingwood, Australia.
Cramp, S.; Perrins, C. M. 1977-1994. Handbook of the birds of Europe, the Middle East and Africa. The birds of the western Palearctic. Oxford University Press, Oxford.
Turbott, E. G. 1990. Checklist of the birds of New Zealand. Ornithological Society of New Zealand, Wellington.

Taxonomic note

Ardea intermedia, A. brachyrhyncha and A. plumifera (del Hoyo and Collar 2014) were previously placed in the genus Mesophoyx and lumped as M. intermedia following Sibley and Monroe (1990, 1993).

Synonym(s)
Ardea intermedia Christidis and Boles (2008), Ardea intermedia intermedia Christidis and Boles (1994), Ardea intermedia intermedia Christidis and Boles (2008), Egretta intermedia Cramp and Simmons (1977-1994), Egretta intermedia Dowsett and Forbes-Watson (1993), Egretta intermedia Turbott (1990), Egretta intermedia intermedia Cramp and Simmons (1977-1994), Egretta intermedia intermedia Dowsett and Forbes-Watson (1993), Egretta intermedia intermedia Turbott (1990)

Ecology
Behaviour North-Asian populations of this species are fully migratory, leaving Japan in September-October to winter in the Philippines and Borneo (Kushlan and Hancock 2005), and returning to breeding colonies in April (del hoyo et al. 1992). The majority is predominantly sedentary however, with some populations making limited nomadic or partially migratory movements (Brown et al. 1982) in response to changing water levels (Hockey et al. 2005). The breeding season varies regionally (del hoyo et al. 1992), but is usually centered around the wet season (Kushlan and Hancock 2005), with birds breeding in mixed-species colonies (del hoyo et al. 1992) of between 7, 20 (Hockey et al. 2005) and hundreds of pairs (sometimes up to thousands) (Marchant and Higgins 1990). The species is diurnal (del hoyo et al. 1992, Kushlan and Hancock 2005) and usually feeds singly, but old records suggest (Kushlan and Hancock 2005) that it may form flocks of 15-20 individuals (sometimes up to 250) (Brown et al. 1982, del hoyo et al. 1992), occasionally forming concentrations around permanent water during droughts (Kushlan and Hancock 2005). During the night the species roosts communally in trees over water (del hoyo et al. 1992, Hockey et al. 2005) in groups of 20 or more (Marchant and Higgins 1990). Habitat The species inhabits lowlands from sea-level to 1,000 m in Sumatra, and 1,450 m in Nepal (del hoyo et al. 1992). It shows a preference for sheltered flood-plains and seasonal wetlands with water less than 80 mm deep and emergent grasses, herbs, sedges, reeds or rushes and abundant aquatic vegetation (Marchant and Higgins 1990) (generally avoiding areas where vegetation is too thick for feeding) (Kushlan and Hancock 2005). Such habitats include seasonally flooded marshes, inland deltas (e.g. Okavango Basin, Botswana) (Hockey et al. 2005), ponds, swamp forest (Kushlan and Hancock 2005), freshwater swamps, pools, rivers, streams, rice-fields, the margins of freshwater, brackish and saltwater lakes (Brown et al. 1982, del hoyo et al. 1992, Kushlan and Hancock 2005), wet meadows, and flooded and dry pasture near water (Brown et al. 1982, del hoyo et al. 1992, Hockey et al. 2005, Kushlan and Hancock 2005). It occurs less often in coastal habitats, but may roost in mangrove swamps (Hancock and Kushlan 1984, del hoyo et al. 1992), and frequents mudflats, tidal estuaries (del hoyo et al. 1992), coastal lagoons (Brown et al. 1982), saltmarshes, and tidal streams and rivers (Marchant and Higgins 1990, Kushlan and Hancock 2005). Diet In aquatic habitats the diet of this species consists predominantly of fish less than 10 cm long (del hoyo et al. 1992, Hockey et al. 2005) (including eels, perch Macquaria, gudgeon and mosquitofish Gambusia) (Kushlan and Hancock 2005), as well as frogs, crustaceans (e.g. crayfish) (del hoyo et al. 1992, Hockey et al. 2005, Kushlan and Hancock 2005) and aquatic insects (e.g. leeches, water bugs and dragonfly larvae) (del hoyo et al. 1992, Hockey et al. 2005, Kushlan and Hancock 2005). It will also take terrestrial prey in drier habitats (Kushlan and Hancock 2005) including grasshoppers (del hoyo et al. 1992, Hockey et al. 2005), mole crickets, bugs and beetles, snakes (Kushlan and Hancock 2005), spiders (del hoyo et al. 1992, Hockey et al. 2005, Kushlan and Hancock 2005) lizards (del hoyo et al. 1992, Kushlan and Hancock 2005), and exceptionally birds (del hoyo et al. 1992). Breeding site The species breeds colonially with other species (del hoyo et al. 1992) but does not concentrate into dense groups; individual nests being typically situated 0.5 m away from each other (Marchant and Higgins 1990). The nest is a shallow platform of sticks and other marshland vegetation (Brown et al. 1982, Hockey et al. 2005, Kushlan and Hancock 2005) usually positioned in trees standing in water or over reedbeds (Brown et al. 1982, Marchant and Higgins 1990) (e.g. in inland swamps or mangroves) (Kushlan and Hancock 2005), at heights of 3-6 m and occasionally up to 20 m (del hoyo et al. 1992). The species may also nest on ledges, in reedbeds or in bushes (Brown et al. 1982).

Threats
This species has declined markedly in Japan since the 1960s due to pollution and the disturbance of nesting colonies (Hancock and Kushlan 1984, del hoyo et al. 1992). The species is also threatened in the Northern Territory of Australia by the degradation of flood-plain habitats owing to grazing, burning, invasion by introduced plants (Marchant and Higgins 1990) (particularly Mimosa pigra and Salvinia molesta (Maddock 2000)), reduced water flows from drainage and water diversion for irrigation (Marchant and Higgins 1990, McKilligan 2005), levee breaking by feral buffalo (Marchant and Higgins 1990, Maddock 2000) (allowing salt intrusion and accumulation of tidal sediment (Marchant and Higgins 1990)), clearing of swamp forest, and pollution from mineral extraction (Maddock 2000). Utilisation This species is hunted and traded at traditional medicine markets in Nigeria (Nikolaus 2001).

References
Brazil, M. 2009. Birds of East Asia: eastern China, Taiwan, Korea, Japan, eastern Russia. Christopher Helm, London.

Brown, L. H.; Urban, E. K.; Newman, K. 1982. The birds of Africa vol I. Academic Press, London.

del Hoyo, J.; Elliot, A.; Sargatal, J. 1992. Handbook of the Birds of the World, vol. 1: Ostrich to Ducks. Lynx Edicions, Barcelona, Spain.

Delany, S.; Scott, D. 2006. Waterbird population estimates. Wetlands International, Wageningen, The Netherlands.

Hancock, J.; Kushlan, J. 1984. The herons handbook. Croom Helm, London.

Hockey, P. A. R.; Dean, W. R. J.; Ryan, P. G. 2005. Roberts birds of southern Africa. Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa.

Kushlan, J. A.; Hancock, J. A. 2005. The herons. Oxford University Press, Oxford, U.K.

Maddock, M. 2000. Herons in Australia and Oceania. In: Kushlan, J. A.; Hafner, H. (ed.), Heron conservation, pp. 123-149. Academic Press, San Diego.

Marchant, S.; Higgins, P. J. 1990. Handbook of Australian, New Zealand and Antarctic birds, 1: ratites to ducks. Oxford University Press, Melbourne.

McKilligan, N. 2005. CSIRO, Collingwood, Australia.

Nikolaus, G. 2001. Bird exploitation for traditional medicine in Nigeria. Malimbus 23: 45-55.

Further web sources of information
Species factsheet from HeronConservation - The IUCN-SSC Heron Specialist Group

Text account compilers
Ekstrom, J., Butchart, S., Malpas, L.

Recommended citation
BirdLife International (2014) Species factsheet: Mesophoyx intermedia. Downloaded from http://www.birdlife.org on 21/09/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/09/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - Intermediate egret (Mesophoyx intermedia) 0

Key facts
Current IUCN Red List category Not Recognised
Family Ardeidae (Herons)
Species name author (Wagler, 1829)