HeronConservation

The IUCN-SCC Heron Specialist Group

Waterbird Population Estimates for Herons

Below are the current (2012) estimates of the numbers of heron in various populations. Depending on the species, estimates may be for the entire species, a subspecies, or a geographic population. These estimates were derived by Wetlands International in partnership with HeronConservation and others. The entire report with information on the processes used may be obtained through Wetlands International.

Estimates are in all cases only that, and base on the best information available and best professional judgment of those who know the populations best. As information increases, estimates will be updated. HeronConservation will continue to partner with Wetlands International and the Ramsar Convention in periodically updating these estimates. All are invited to participate in making these estimates more accurate. Please communicate your data and suggestions to the HeronConservation Co-chairs or Steering Committee Members.

Heron Population Estimates

Scientific name Common name Population Name Population Size. Start Year Population Size. End Year Minimum Maximum Population Size.Notes Population Trend. Start Year Population Trend. End Year Trend Population Trend. Notes
Ardea cinerea Grey Heron cinerea, Sub-Saharan Africa 1990 2000 100,000 1,000,000 1991 2001 STA
cinerea, Northern & Western Europe 2000 2000 263,000 286,000 1997 2007 INC Wetlands International 2012. Trend 1990-2007: +2.2% p.a. – Increase
cinerea, Central & Eastern Europe 2000 2000 189,000 256,000 1995 2005 INC
cinerea, West & South-west Asia (bre) 2002 2002 25,000 1,000,000 1997 2007 INC Wetlands International 2012. Trend 1989-2007: +2.4% p.a. – Increase
cinerea, South Asia 0 0 100,000 100,000 0 0 Unknown
jouyi, E, SE Asia 1987 1991 100,000 1,000,000 0 0 Unknown
jouyi, Sumatra 0 0 1,000 2,000 0 0 Unknown
monicae 0 0 7,500 12,500 1984 1997 STA
firasa 2001 2001 5,000 5,000 1991 2001 DEC
Ardea herodias Great Blue Heron herodias, C & NE North America 0 0 124,000 125,000 This estimate includes two other populations (W N Americas and W N Americas, N Mexico). 1966 2000 INC
herodias, W North America 0 0 -1 -1 The population estimate for C & NE N America includes the estimate for this population and also the W N Americas, N Mexico population. 1966 2000 STA
herodias, W North America, N Mexico 0 0 -1 -1 The population estimate for C & NE N America includes the estimate for this population and also the W N Americas population. 0 0 Unknown
herodias, Baja California, Mexico 0 0 -1 -1 0 0 Unknown
fannini 1997 2007 9,500 11,000 Estimate refers to Nesting adults. 1997 2007 DEC
wardi 0 0 -1 -1 1966 2000 INC
occidentalis, Florida 2006 2006 1,500 1,500 1980 2007 DEC
occidentalis, Caribbean 0 0 -1 -1 According to Birdlife International 2008a., occurs mainly as non-breeding migrant. Resident population presumably <100 individuals. 0 0 Unknown
occidentalis, Central America 2005 2005 29,800 122,000 0 0 Unknown
cognata 2004 2004 1,000 1,000 0 0 Unknown
Ardea cocoi Cocoi Heron South America, Panama 2005 2011 100,000 1,000,000 2001 2010 STA
Ardea pacifica White-necked Heron Australia 2004 2011 10,000 25,000 Estimate based on reassessment of previous information and recent information that suggests population level may reach or exceed 25,000 only briefly. 1982 2011 FLU
Casmerodius albus Great Egret, Eastern Great Egret modestus, South Asia (non-bre) 2001 2005 25,000 100,000 20: 11,000 counted in South Asia in 2003. 1977 1991 STA
albus, W C & SE Europe/Black Sea & Mediterranean 2006 2006 38,800 54,300 1996 2006 INC Wetlands International 2012. Trend 1989-2006: +3.9% p.a. – Increase.
modestus, E Asia (non-bre) 2001 2001 10,000 100,000 20: 16,800 counted in 2004. 1987 1991 DEC
albus, Western Asia/South-west Asia 2002 2002 25,000 100,000 1997 2007 DEC? Wetlands International 2012. Trend 1991-2007: -2.6% p.a. – Significant long-term decline. However, most data being from only one country, Iran.
modestus, Indonesia 0 0 -1 -1 0 0 Unknown
melanorhynchos, Sub-Saharan Africa & Madagascar 2001 2001 100,000 500,000 1991 2001 INC
modestus, Australia 1995 2011 25,000 100,000 Estimate based on review of previous information and recent information that suggests total numbers remain between 25,000 and 100,000. Numbers in New Guinea can reach the same level but likely to be mostly migrants from Australia. 1982 2011 FLU
egretta, North America 0 0 270,000 270,000 1966 2000 INC
modestus, New Zealand 0 0 100 100 0 0 Unknown
egretta, Mexico 0 0 -1 -1 0 0 Unknown
egretta, Central America 2005 2005 52,500 180,000 2005 2005 STA?
egretta, Caribbean 2006 2007 11,100 30,500 Total of data presented in BirdLife International 2008a. 0 0 Unknown
egretta, South America 2005 2011 1,000,000 1,000,001 2001 2010 STA
Mesophoyx intermedia Intermediate Egret intermedia, South Asia 0 0 25,000 100,000 20: 22,000 counted in South Asia in 2004. 0 0 Unknown
intermedia, E, SE Asia 0 0 25,000 100,000 20: >10,000 counted in 2002-2004. 0 0 Unknown
brachyrhyncha, Sub-Saharan Africa 2001 2001 25,000 100,000 1991 2001 STA
plumifera 1995 2011 100,000 1,000,000 Numbers clearly between 100,000 and 1,000,000 either in Australia or S New Guinea; probable migration precludes summation. Additional birds in Indonesia (no information) or failure to confirm migration would raise possibility of estimate in excess of 1,0 1982 2011 DEC? In Australia, northern colonies secure but overall likely declining trend due to loss of southernmost colonies due to river regulation for irrigation.
Ardea melanocephala Black-headed Heron Sub-Saharan Africa 2001 2001 100,000 500,000 1991 2001 INC
Ardea humbloti Madagascar Heron Madagascar 0 0 1,000 3,000 1990 2005 DEC
Ardea insignis White-bellied Heron S & SE Asia 2005 2005 250 1,000 1985 2005 DEC
Ardea sumatrana Great-billed Heron SE Asia 0 0 10,000 100,000 1975 1985 DEC
Australia 1999 1999 7,500 7,500 Occurs at low density often in habitat remote from observation; thus, data deficient. Habitat is largely unchanged and not at high risk. 1990 1999 STA
Ardea goliath Goliath Heron Sub-Saharan Africa 0 0 10,000 100,000 1991 2001 STA
SW Asia 1987 1991 50 50 0 0 Unknown
S Asia 1987 1991 20 20 0 0 Unknown
Ardea purpurea Purple Heron purpurea, Tropical Africa 2001 2001 75,000 100,000 1991 2001 STA
purpurea, West Europe & West Mediterranean/West Africa 1986 2008 12,500 13,100 1990 2008 INC BirdLife International 2004b. Population increased in the Netherlands and Italy, remained stable in France and Portugal and fluctuated in Spain between 1990 and 2000, but increased in France by 47% between 2000 and 2008.
purpurea, East Europe & South-west Asia/Sub-Saharan Africa 2006 2006 135,000 300,000 1990 2000 DEC
purpurea, SW Asia (bre) 2006 2006 10,000 25,000 0 0 Unknown
madagascariensis 0 0 5,000 10,000 1991 2001 STA
bournei 0 0 1 50 1982 1992 DEC
manilensis, South Asia 1987 1991 25,000 25,000 1977 1991 STA
manilensis, E & SE Asia 1987 1991 10,000 100,000 0 0 Unknown
Bubulcus ibis Cattle Egret ibis, Southern Africa 1996 2001 100,000 1,000,000 1986 1996 INC
ibis, Tropical Africa 1990 2001 1,000,000 1,000,001 1990 2000 STA
ibis, North-west Africa 1984 2000 100,000 150,000 1993 2003 INC
ibis, South-west Europe 1995 2008 260,000 320,000 Large increase in France between 1994 (2,300 bp) and 2008 (14,300 bp) 1995 2005 INC
ibis, East Mediterranean & South-west Asia 2005 2005 10,000 100,000 1997 2007 Unknown Wetlands International 2012. Trend 1990-2007: -2.1% p.a. – Uncertain.
ibis, North America 0 0 1,000,000 1,000,001 Apparently does not breed in Canada anymore, certainly not in Ontario (Weseloh, C. In litt. 2012) 1966 2000 STA
ibis, Mexico 0 0 -1 -1 0 0 Unknown
ibis, Central America 2005 2005 262,000 2,120,000 2005 2005 INC
ibis, Caribbean 2006 2007 43,800 147,000 Total of data presented in BirdLife International 2008a and of which 25,000-100,000 estimated for Cuba (Acosta-Cruz, M. and Mugica-Valdés, L. 2006.) 0 0 Unknown
ibis, South America 1993 1993 1,000,000 1,000,001 1982 1992 INC
seychellarum 2001 2001 1 10,000 1991 2001 STA
coromanda, South Asia 1987 1991 100,000 1,000,001 0 0 Unknown
coromanda, E, SE Asia 2001 2001 100,000 1,000,000 1981 1991 STA
coromanda, Oceania 1999 2011 25,000 1,000,000 Estimate in broad range based on size of large colonies in far N Australia and status as common and locally breeding in coastal E Australia. 1982 2011 INC Ongoing, long-term trend of increase throughout population's range.
Butorides virescens Green Heron virescens, Central & E North America 0 0 -1 -1 1966 2000 DEC
virescens, Mexico 0 0 -1 -1 0 0 Unknown
virescens, Central America 2005 2005 23,000 60,000 0 0 Unknown
virescens, Caribbean 2006 2007 3,080 12,300 Total of data presented in BirdLife International 2008a 0 0 Unknown
bahamensis 0 0 -1 -1 0 0 Unknown
anthonyi 0 0 -1 -1 1966 2000 INC
frazari 0 0 -1 -1 0 0 Unknown
Butorides striata Striated Heron striata, Central & South America 0 0 -1 -1 0 0 Unknown
striata, South America 2005 2011 100,000 1,000,000 2001 2010 STA
sundevalli 0 0 -1 -1 0 0 Unknown
brevipes 0 0 1 25,000 Widespread in the whole of the Red Sea and the Gulf of Aden (528); birds on Indian Ocean coast of N Somalia are probably this form (18). 0 0 Unknown
atricapilla 2001 2001 100,000 1,000,000 1991 2001 STA
rutenbergi 2001 2001 1 25,000 1991 2001 STA
rhizophorae 2001 2001 1 10,000 1992 2002 STA
degens 2001 2001 1 10,000 0 0 Unknown
crawfordi 2001 2001 1 5,000 1991 2001 STA
albolimbata 0 0 1 10,000 0 0 Unknown
chloriceps 0 0 25,000 25,000 1991 2001 DEC
spodiogaster 0 0 -1 -1 0 0 Unknown
amurensis 0 0 -1 -1 0 0 Unknown
actophila 0 0 -1 -1 0 0 Unknown
javanica 2006 2006 10,000 100,000 0 0 Unknown
moluccara, Moluccas 0 0 -1 -1 0 0 Unknown
moluccara, NW New Guinea 0 0 -1 -1 0 0 Unknown
solomonensis 2001 2001 1 25,000 0 0 Unknown
idenburgi 0 0 -1 -1 0 0 Unknown
flyensis 0 0 -1 -1 0 0 Unknown
stagnatilis, N Australia 0 0 -1 -1 0 0 Unknown
stagnatilis, NW Australia 0 0 -1 -1 0 0 Unknown
stagnatilis, NE Western Australia 0 0 -1 -1 0 0 Unknown
patruelis 0 0 100 200 1971 1987 DEC
macrorhynchus, E Australia 0 0 -1 -1 0 0 Unknown
macrorhynchus, SC New Guinea, NE Queensland 0 0 -1 -1 0 0 Unknown
carcinophilus 0 0 -1 -1 0 0 Unknown
steini 0 0 -1 -1 0 0 Unknown
Ardeola ralloides Squacco Heron ralloides, SW Europe NW Africa (bre) 1995 2005 2,700 5,600 1995 2005 INC
ralloides, C & E Europe/Black Sea & E Mediterranean (bre) 1995 2005 42,000 76,000 1995 2005 DEC
ralloides, West & South-west Asia/Sub-Saharan Africa 1987 1991 25,000 100,000 1990 2000 STA
paludivaga, Sub-Saharan Africa & Madagascar 2006 2006 300,000 600,000 1991 2001 INC? Trolliet, B. In litt. 2011. The trend is increasing in Lake Chad Basin as in Inner Niger Delta.
Ardeola grayii Indian Pond-heron grayii, SW, S Asia 1987 1991 100,000 1,000,000 0 0 Unknown
grayii, Myanmar, Bay of Bengal 0 0 -1 -1 0 0 Unknown
phillipsi 0 0 -1 -1 0 0 Unknown
Ardeola bacchus Chinese Pond-heron E, SE & S Asia 2001 2001 25,000 1,000,000 1981 1991 STA
Ardeola speciosa Javan Pond-heron speciosa 0 0 -1 -1 0 0 Unknown
continentalis 1987 1991 10,000 100,000 0 0 Unknown
Ardeola idae Madagascar Pond-heron Madagascar & Aldabra/Central & Eastern Africa 2001 2001 2,000 6,000 1995 2005 DEC
Ardeola rufiventris Rufous-bellied Heron Tropical Eastern & Southern Africa 2006 2006 10,000 100,000 1990 2000 STA
Egretta rufescens Reddish Egret rufescens, S USA 1991 2006 5,000 7,000 Green 2006. 1,215-1,330 breeding pairs in southern USA; 800-1,000 breeding pairs in Mexico (inc. dickeyi); 200 breeding pairs in Bahamas. 1991 2006 DEC
rufescens, Mexico 0 0 1 10,000 0 0 Unknown
rufescens, Central America 2006 2006 1 10,000 Green, C. In litt. 2012. 282 breeding pairs in southern Mexico (Chiapas, Oaxaca in 2007-2008) and 95 breeding pairs in Tamaulipas (in 2008). 0 0 Unknown
rufescens, Caribbean 2006 2010 213 213 Data from Bahamas: 50 bp in Great Inagua, 19 bp in Grand Bahama, 2 bp in Bimini Island. 0 0 Unknown
rufescens, N South America 0 0 1 10,000 0 0 Unknown
dickeyi 2007 2008 2,250 2,260 753 Breeding Pairs. 0 0 Unknown
Ardea picata Pied Heron Australia - Sulawesi 1995 2002 25,000 100,000 Estimate based on high counts in S New Guinea, and numbers breeding in far N Australia, which although not necessarily additive nevertheless suggest overall numbers in the range 25,000-100,000.. 2000 2010 STA Trend assumed stable based on habitat in Australia and New Guinea being mostly near-natural.
Egretta vinaceigula Slaty Egret South-central Africa 2005 2005 3,000 5,000 1995 2005 DEC
Egretta ardesiaca Black Heron Sub-Saharan Africa 1999 1999 25,000 100,000 1990 2000 INC? 920. Since the mid 1980’s, numbers are locally increasing.
Egretta tricolor Tricoloured Heron tricolor 0 0 -1 -1 0 0 Unknown
ruficollis, USA (bre) 0 0 293,000 293,000 1966 2000 STA
ruficollis, Mexico 2006 2006 1 1,500 0 0 Unknown No new data
ruficollis, Central America 2005 2005 3,350 6,800 0 0 Unknown
ruficollis, Caribbean 2006 2007 12,000 27,400 Total of data presented in BirdLife International 2008a and of which 10,000-25,000 estimated for Cuba (Acosta-Cruz, and Mugica-Valdés 2006). 0 0 Unknown
Egretta novaehollandiae White-faced Heron novaehollandiae 2004 2008 10,000 100,000 Estimate based on summed maximum counts indicating at least 10,000 birds and common status (at low density) across dryland habitats; much habitat is not surveyed. 0 0 Unknown
parryi 0 0 -1 -1 0 0 Unknown
Egretta caerulea Little Blue Heron North America 0 0 225,000 300,000 1966 2000 DEC
Mexico 0 0 75,000 150,000 0 0 Unknown
Central America 2005 2005 701 1,500 0 0 Unknown
Caribbean 2006 2007 12,300 35,900 Total of data presented in BirdLife International 2008a. 0 0 Unknown
South America 2005 2011 100,000 100,000 2001 2010 STA?
Egretta thula Snowy Egret thula 0 0 215,000 215,000 1982 1992 STA
thula, Mexico 0 0 75,000 150,000 0 0 Unknown
thula, Central America 2005 2005 11,300 26,900 0 0 Unknown
thula,Caribbean 2006 2007 12,500 36,100 Total of data presented in BirdLife International 2008a. 0 0 Unknown
thula, South America 2005 2011 300,000 1,000,000 2001 2010 STA
brewsteri 2006 2006 100,000 1,000,000 1966 2000 INC
Egretta garzetta Little Egret garzetta, Sub-Saharan Africa 2001 2001 200,000 500,000 1990 2000 STA
garzetta, Western Europe NW Africa 1998 1998 125,000 143,000 1997 2007 INC Wetlands International 2012. Trend 1990-2007: +7.9% p.a. – Increase.
garzetta, Central & E Europe Black Sea E Mediterranean 1986 1997 44,000 72,400 1988 1998 STA
garzetta, Western Asia/SW Asia NE & Eastern Africa 1987 1991 25,000 100,000 1997 2007 Unknown Wetlands International 2012. Trend 1992-2007: +1% p.a. – Uncertain.
garzetta, South Asia 0 0 100,000 200,000 20: 48,000 counted in 2002. 0 0 Unknown
garzetta, E, SE Asia 2001 2001 100,000 1,000,000 1981 1991 STA
garzetta, West Indies 2006 2006 30 60 Colonised in early 1990’s, (529). 10-20 pairs (30-60 individuals). See 336. 1991 2001 INC
nigripes 1987 1991 25,000 1,000,001 0 0 Unknown
immaculata 2002 2004 25,000 100,000 Estimate based on review of previous information and some recent information, which suggest that total numbers in Australia and S New Guinea are between 25,000 and 100,000, assuming most of the S New Guinea birds are immaculata. If immaculata and nigripes 0 0 Unknown
dimorpha, Madagascar 0 0 6,000 20,000 0 0 DEC
dimorpha, Aldabra & Amirante Is 0 0 3,000 9,000 1991 2001 STA
dimorpha, E African coast 2001 2001 10,000 10,000 1991 2001 STA
Egretta gularis Western Reef-egret gularis, West Africa 1990 2000 10,000 100,000 1991 2001 STA
schistacea, North-east Africa & Red Sea 1990 2000 10,000 100,000 1990 2000 STA
schistacea, South-west Asia & South Asia 1987 1991 17,000 17,000 1990 2000 STA
Egretta eulophotes Chinese Egret E, SE Asia 2000 2010 3,000 4,100 Hwang (2011) estimates 1,000-1,600 breeding individuals in South Korea from 2000 to 2010, 1,000-1,200 (Collar 2001) or 1,200-1,500 (BASP 2004) in DPRK, and 1,000 birds in China (Zhiying 2009). 0 0 STA
Egretta sacra Pacific Reef-egret sacra 2006 2006 100,000 1,000,000 Regarded as 'rapidly declining and very rare' in China (125). 1985 2005 STA? Regarded as 'rapidly declining and very rare' in China (125).
albolineata 0 0 1,000 2,000 1990 2000 STA
Syrigma sibilatrix Whistling Heron sibilatrix 2005 2011 25,000 100,000 2001 2010 STA
forstersmithi 2011 2011 10,000 10,000 2006 2010 FLU
Pilherodius pileatus Capped Heron C & S America 2005 2011 10,000 25,000 2001 2010 STA
Nyctanassa violacea Yellow-crowned Night-heron violacea, North America 0 0 75,000 150,000 1966 2000 STA
violacea, Mexico to Honduras 0 0 -1 -1 No new data other than estimate of 1,400-1,900 for Central America (Komar et al. 2006). 0 0 Unknown
violacea, Socorro Island 0 0 -1 -1 0 0 Unknown
caliginis 2004 2004 900 900 1982 1992 STA
cayennensis 0 0 -1 -1 0 0 Unknown
bancrofti 0 0 -1 -1 No new data other than estimate of 2,203-7,603 for Caribbean (Birdlife International 2008a). 0 0 Unknown
pauper 0 0 -1 -1 0 0 Unknown
Nycticorax nycticorax Black-crowned Night-heron nycticorax, W Europe NW Africa (bre) 2000 2005 61,000 97,000 1990 2000 INC BirdLife International 2004b. Increased in France and Belgium, declined in Portugal, stable in other countries between 1990 and 2000. Depleted.
nycticorax, C & E Europe/Black Sea & E Mediterranean (bre) 1990 2000 92,100 138,000 1990 2000 INC BirdLife International 2004b. Increased in Turkey and Serbia, declines in Slovenia, Bosnia-Herzegovina and Albania, stable in other countries between 1990 and 2000. The breeding population also declined in Greece during the same period (Yfantis and Kazant
nycticorax, Western Asia/SW Asia & NE Africa 2002 2002 25,000 100,000 1990 2000 STA
nycticorax, Sub-Saharan Africa & Madagascar 2001 2001 25,000 1,000,000 1991 2001 STA
nycticorax, South Asia 0 0 100,000 150,000 33: Population estimate for India 100,000. 1977 1991 STA
nycticorax, E, SE Asia 2006 2006 100,000 1,000,000 1981 1991 STA
nycticorax, North America (bre) 1999 2011 75,000 150,000 2,500-5,000 breeding pairs estimated for Canada (Weseloh, C. In litt. 2012). 1990 2000 STA
nycticorax, Mexico 0 0 -1 -1 0 0 Unknown
nycticorax, Central America 2005 2005 9,600 24,900 0 0 Unknown
nycticorax, Caribbean 2006 2007 6,000 12,300 Total of data presented in BirdLife International 2008a. 0 0 Unknown
nycticorax, northern South America (bre) 2005 2010 50,000 50,000 2001 2010 STA
obscurus 2001 2001 25,000 1,000,000 0 0 Unknown
obscurus, Falkland Islands (Malvinas) 0 0 5,700 10,800 718 estimate 1,900-3,600 pairs (5,700-10,800 individuals). 0 0 Unknown
Nycticorax duboisi Reunion Night-heron Reunion 2005 2005 0 0 Described and last recorded in 1674 (BirdLife International. 2005). 1750 2005 EXT
Nycticorax mauritianus Mauritius Night-heron Mauritius 2005 2005 0 0 Described and last recorded in 1693 (BirdLife International. 2005). 1750 2005 EXT
Nycticorax megacephalus Rodrigues Night-heron Rodrigues 2005 2005 0 0 Described and last recorded in 1726 (BirdLife International. 2005). 1800 2005 EXT
Gorsachius leuconotus White-backed Night-heron Africa 0 0 25,000 100,000 1991 2001 STA
Nycticorax caledonicus Rufous Night-heron caledonicus 0 0 2,000 4,000 1990 2000 STA
manillensis 0 0 -1 -1 0 0 Unknown
pelewensis 2001 2001 1 10,000 0 0 Unknown
mandibularis 2001 2001 10,000 100,000 0 0 Unknown
hilli 2004 2011 25,000 1,000,000 Estimate based on numbers in colonies and consideration of survey difficulties and numbers outside Australia. 1982 2011 FLU Trend is fluctuating; possible long-term decline due to loss of some breeding habitat in E Australia requires confirmation.
Gorsachius magnificus White-eared Night-heron SE Asia 2000 2000 250 1,000 M. Crosby in litt. (2005) estimates 250-999 individuals based on analysis of information presented in 66. Habitat detrimentally transformed at principal site, Shennongjia in Hubei province, China, in 1990’s. 1995 2005 DEC
Gorsachius goisagi Japanese Night-heron E & SE Asia 2005 2005 250 1,000 1975 1995 DEC
Gorsachius melanolophus Malaysian Night-heron South Asia 0 0 -1 -1 0 0 Unknown
SE Asia 0 0 -1 -1 0 0 Unknown
Philippines 0 0 -1 -1 0 0 Unknown
Palawan, Philippines 0 0 1 10,000 0 0 Unknown
Nicobar Is 0 0 1 10,000 0 0 Unknown
Botaurus pinnatus Pinnated Bittern pinnatus 2005 2011 10,000 25,000 No new data other than estimate of 576-2,900 for Central America (Komar et al. 2006). 2001 2010 STA
caribaeus 0 0 -1 -1 0 0 Unknown
Botaurus lentiginosus American Bittern North America 2000 2000 2,980,000 2,980,000 Estimate from BBS 992,000 pairs (2,976,000 individuals). For populations over 2 million birds, Ramsar criterion 5 (20,000 or more waterbirds) applies. 1966 2004 DEC?
Botaurus stellaris Great Bittern stellaris, W Europe NW Africa (bre) 1983 1999 5,850 6,700 1995 2005 DEC
stellaris, C & E Europe Black Sea & E Mediterranean (bre) 1993 1993 53,800 125,000 1995 2005 DEC
stellaris, South-west Asia (win) 2006 2006 25,000 100,000 1990 2000 STA
stellaris, South Asia (non-bre) 0 0 -1 -1 0 0 Unknown
stellaris, S & E Asia (non-bre) 2001 2001 25,000 100,000 1981 1991 DEC
capensis, Southern Africa 1990 2000 5,000 5,000 1986 1996 DEC
Botaurus poiciloptilus Australasian Bittern SW Australia 2009 2010 60 230 Estimate derived by WPE method of number of mature birds x1.5 and based on systematic range-wide surveys in recent years coordinated by BirdLife Australia. 2000 2010 DEC Trend is declining (20-30% within 2 generations (11 years)) due to loss of habitat.
SE Australia 2009 2010 310 960 Estimate derived by WPE method of number of mature birds x1.5 and based on systematic range-wide surveys in recent years coordinated by BirdLife Australia. 2000 2010 DEC Trend is declining (20-30% within 2 generations (11 years)) due to loss of habitat.
New Zealand 2011 2011 1,000 1,500 Estimate reflects better information arising from systematic investigation. 2001 2010 DEC? Trend assumed to be unchanged but requires confirmation.
New Caledonia 2011 2011 -1 -1 2001 2010 EXT?
Ixobrychus involucris Stripe-backed Bittern N South America 1993 1993 100,000 1,000,000 1982 1992 STA
S South America 2011 2011 10,000 25,000 2001 2010 STA
Ixobrychus exilis Least Bittern exilis 2000 2000 128,000 128,000 No new data. 4,500 (1,500 Bpairs) in Canada (COSEWIC. 2009). 0 0 Unknown
pullus 0 0 -1 -1 0 0 Unknown
bogotensis 2011 2011 1,000 1,000 2001 2010 DEC
erythromelas 2005 2011 10,000 25,000 0 0 Unknown
peruvianus 2011 2011 1,000 5,000 2001 2010 STA
minutus, W Europe NW Africa/Subsaharan Africa 2000 2005 11,900 17,900 1995 2005 STA BirdLife International 2004b. Stable or increased in all countries except Portugal between 1990 and 2000. Probably depleted.
Ixobrychus minutus Little Bittern minutus, C & E Europe Black Sea & E Mediterranean/Subsaharan Africa 1995 2005 110,000 325,000 1995 2005 DEC
minutus, West & South-west Asia/Sub-Saharan Africa 1987 1991 25,000 100,000 1990 2000 STA
minutus, South Asia 1987 1991 10,000 25,000 0 0 Unknown
payesii, Sub-Saharan Africa 1990 2000 25,000 100,000 1990 2000 STA
podiceps 0 0 3,000 15,000 0 0 Unknown
dubius 1994 2010 1 10,000 Data inadequate to derive a numerical estimate due to survey difficulties; numbers recorded support 1 - 10,000. 1982 2011 DEC? Trend is possibly declining due to loss of inland habitat.
Ixobrychus novaezelandiae Black-backed Bittern, Australian Little Bittern New Zealand 0 0 0 0 1982 1992 EXT
Ixobrychus sinensis Yellow Bittern Seychelles 0 0 1 300 1991 2001 DEC
South Asia 0 0 -1 -1 0 0 Unknown
E & SE Asia 2006 2006 100,000 1,000,000 42: Recently colonised New Caledonia. 1985 2005 INC
Ixobrychus eurhythmus Schrenck's Bittern E & SE Asia 0 0 1 25,000 1985 1995 DEC
Ixobrychus cinnamomeus Cinnamon Bittern South Asia 1987 1991 25,000 1,000,000 0 0 Unknown
E, SE Asia 2006 2006 100,000 1,000,000 1985 2005 STA
Ixobrychus sturmii Dwarf Bittern Sub-Saharan Africa 1990 2000 25,000 100,000 1990 2000 STA
Ixobrychus flavicollis Black Bittern flavicollis, South Asia 1987 1991 25,000 100,000 0 0 Unknown
flavicollis, E, SE Asia 2006 2006 10,000 100,000 0 0 Unknown
australis, Australia, New Guinea 1999 2002 10,000 100,000 Estimate based on previous information and extent of habitat across several countries. 1991 2000 DEC
australis, Timor 0 0 -1 -1 0 0 Unknown
australis, Rennell Island 2001 2001 1 500 0 0 Unknown
australis, New Britain, New Ireland 2001 2001 1 10,000 0 0 Unknown
woodfordi 2001 2001 1 10,000 0 0 Unknown
Zebrilus undulatus Zigzag Heron South America 2004 2004 1 10,000 0 0 Unknown
Tigrisoma mexicanum Bare-throated Tiger-heron Colombia to Mexico 2005 2005 17,100 47,500 2005 2005 INC
S Mexico 0 0 -1 -1 0 0 Unknown
Tigrisoma fasciatum Fasciated Tiger-heron fasciatum 0 0 1 10,000 0 0 Unknown
salmoni 2005 2005 2,520 5,050 Estimate for whole of Central America. 0 0 Unknown
pallescens 2004 2004 2,000 2,000 0 0 Unknown
Tigrisoma lineatum Rufescent Tiger-heron lineatum 2005 2005 2,700 5,500 Estimate for whole of Central America. 0 0 Unknown
marmoratum 2005 2011 25,000 100,000 2001 2010 STA
Agamia agami Agami Heron C & S America 2005 2011 10,000 25,000 0 0 Unknown
Zonerodius heliosylus Forest Bittern New Guinea 2006 2006 1 10,000 Very difficult to detect and invariably overlooked; thus virtually unknown in the wild (Bishop 2003). 1985 2005 DEC
Tigriornis leucolopha White-crested Tiger-heron W & C Africa 2006 2006 25,000 100,000 0 0 Unknown
Cochlearius cochlearius Boat-billed Heron cochlearia 2011 2011 25,000 100,000 2001 2010 DEC
zeledoni 0 0 -1 -1 0 0 Unknown
phillipsi 2005 2005 14,800 46,300 Estimate for whole of Central America. 0 0 Unknown
ridgwayi 0 0 -1 -1 0 0 Unknown
panamensis 0 0 -1 -1 0 0 Unknown