Species

Justification
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

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.
AOU. 1998. Check-list of North American birds. American Ornithologists' Union, Washington, D.C.
Christidis, L.; Boles, W. E. 1994. The taxonomy and species of birds of Australia and its territories. Royal Australasian Ornithologists' Union, Melbourne.
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.
Dowsett, R. J.; Forbes-Watson, A. D. 1993. Checklist of birds of the Afrotropical and Malagasy regions. Tauraco Press, Li
SACC. 2006. A classification of the bird species of South America. Available at: http://www.museum.lsu.edu/~Remsen/SACCBaseline.html.

Taxonomic note
Butorides sundevalli and B. striatus (Sibley and Monroe 1990, 1993) have been lumped into B. striata following AOU (2003). Gender agreement of B. striata follows David and Gosselin (2002b).

Synonym(s)
Butorides striatus BirdLife International (2004), Butorides striatus Cramp and Simmons (1977-1994), Butorides striatus Dowsett and Forbes-Watson (1993), Butorides striatus

Population justification
The global population is estimated to number c.150,000-1,200,000 individuals (Wetlands International 2006), while national population estimates include: c.10,000-100,000 breeding pairs and c.1,000-10,000 individuals on migration in China; < c.100 breeding pairs, c.50-1,000 wintering individuals and c.50-1,000 individuals on migration in Taiwan; c.100-10,000 breeding pairs and c.50-1,000 individuals on migration in Korea; c.10,000-100,000 breeding pairs and c.1,000-10,000 individuals on migration in Japan and possibly c.100-10,000 breeding pairs and c.50-1,000 individuals on migration in Russia (Brazil 2009).

Trend justification
The overall population trend is decreasing, although some populations may be stable and others have unknown trends (Wetlands International 2006).

Ecology
Behaviour The majority of this species is sedentary although northern breeding populations are migratory and populations in Africa may perform local movements relating to seasonal rainfall (del Hoyo et al. 1992). The timing of breeding varies geographically but often occurs during the rains in the tropics (del Hoyo et al. 1992, Kushlan and Hancock 2005). The species is highly territorial and often forages and nests singly (del Hoyo et al. 1992, Kushlan and Hancock 2005), occasionally also nesting in loosely spaced single-species groups of 5-15 pairs, or even in larger breeding aggregations of several hundred (300-500) (del Hoyo et al. 1992) pairs (Kushlan and Hancock 2005). Habitat The species shows a preference for forested water margins (Hancock and Kushlan 1984, Kushlan and Hancock 2005) such as mangrove-lined shores and estuaries, or dense woody vegetation fringing ponds, rivers, lakes and streams (Hancock and Kushlan 1984, del Hoyo et al. 1992, Kushlan and Hancock 2005). Other suitable habitats include river swamps, canals, artificial ponds, salt-flats (Kushlan and Hancock 2005), mudflats, tidal zones, exposed coral reefs (del Hoyo et al. 1992), reedbeds, grassy marshland, pastures, rice-fields and other flooded cultivation (del Hoyo et al. 1992). Diet Its diet varies considerably over its range (del Hoyo et al. 1992) but usually consists predominantly of fish (del Hoyo et al. 1992, Kushlan and Hancock 2005) as well as amphibians (del Hoyo et al. 1992) (e.g. frogs) (Kushlan and Hancock 2005), insects (del Hoyo et al. 1992) (e.g. water beetles, grasshoppers and dragonflies) (Kushlan and Hancock 2005), spiders, leeches, crustaceans (e.g. crabs and prawns), molluscs (del Hoyo et al. 1992), earthworms, polychaete worms, birds (Kushlan and Hancock 2005), small reptiles and mice (del Hoyo et al. 1992). Breeding site The nest is a small, shallow structure of twigs (Kushlan and Hancock 2005) placed well hidden amongst the branches of trees or bushes (especially mangroves Rhizophora spp. and Avicennia spp., or Allocasuarina spp., Myoporum spp., Callistemon spp., Hibiscus spp., Casuarina spp., Syzygium spp. and Inga spp.) (Kushlan and Hancock 2005) 0.3-10 m above the surface of water or above the ground (del Hoyo et al. 1992).

Threats
The species is threatened by human disturbance, pesticides (del Hoyo et al. 1992) and habitat destruction (e.g. the loss of mangroves) (Kushlan and Hancock 2005). Utilisation The species is taken for food in some areas (del Hoyo et al. 1992).

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

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

Further web sources of information
Hear sounds for this species from xeno-canto, the community database of shared bird sounds from around the world.

Species factsheet from HeronConservation - The IUCN-SSC Heron Specialist Group

View photos and videos, and hear sounds of this species from the Internet Bird Collection

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

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2013) Species factsheet: Butorides striata. Downloaded from http://www.birdlife.org on 24/05/2013. Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 24/05/2013.

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

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