Bubulcus ibis -- (Linnaeus, 1758)ANIMALIA -- CHORDATA -- AVES -- PELECANIFORMES -- ARDEIDAECommon names: Cattle Egret; Héron garde-boeufs

European Red List AssessmentEuropean Red List Status

LC -- Least Concern, (IUCN version 3.1)

Assessment InformationYear published: 2015Date assessed: 2015-03-31Assessor(s): BirdLife InternationalReviewer(s): Symes, A.Compiler(s): Ashpole, J., Burfield, I., Ieronymidou, C., Pople, R., Van den Bossche, W., Wheatley, H. &

Wright, L.Assessment RationaleEuropean regional assessment: Least Concern (LC)EU27 regional assessment: Least Concern (LC)

At both European and EU27 scales this species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence 10% in ten years or three generations, or with a specified population structure). 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).

For these reasons the species is evaluated as Least Concern within both Europe and the EU27.

OccurrenceCountries/Territories of OccurrenceNative:Armenia; Azerbaijan; Cyprus; France; Georgia; Greece; Italy; Montenegro; Netherlands; Portugal; Romania; Russian Federation; Serbia; Spain; Canary Is. (to ES); Turkey; Gibraltar (to UK)Vagrant:Albania; Austria; Belarus; Belgium; Bosnia and Herzegovina; Bulgaria; Croatia; Czech Republic; Denmark; Finland; Germany; Hungary; Iceland; Ireland, Rep. of; Latvia; Liechtenstein; Lithuania; Luxembourg; Macedonia, the former Yugoslav Republic of; Malta; Norway; Poland; Slovenia; Sweden; Switzerland; United Kingdom

PopulationThe European population is estimated at 76,100-92,300 pairs, which equates to 152,000-185,000 mature individuals. The population in the EU27 is estimated at 72,100-84,600 pairs, which equates to 144,000-169,000 mature individuals. For details of national estimates, see Supplementary PDF.

TrendIn Europe and the EU27 the population size is estimated to be decreasing by less than 25% in 24.3 years (three generations). For details of national estimates, see Supplementary PDF.

Habitats and EcologyMost populations of this species are partially migratory, making long-distance dispersive movements related to food resources in connection with seasonal rainfall (Martínez-Vilalta et al. 2014). It breeds colonially, often with other species, in groups that number from a few dozen to several thousand pairs (Martínez-Vilalta et al. 2014). The nesting effort of the species is related to rainfall patterns, leading to an annual variation in productivity (Kushlan and Hancock 2005). Outside of the breeding season the species remains gregarious (Brown et al. 1982, Martínez-Vilalta et al. 2014), feeding in loose flocks of 10–20 individuals (Brown et al. 1982) and often gathering in flocks of hundreds or even thousands of individuals where food is abundant (Martínez-Vilalta et al. 2014). The species is a diurnal feeder (Martínez-Vilalta et al. 2014) and commonly

associates with native grazing mammals or domesticated livestock (Kushlan and Hancock 2005) and may follow farm machinery to capture disturbed prey. The species inhabits open grassy areas such as meadows (Martínez-Vilalta et al. 2014), livestock pastures (Kushlan and Hancock 2005), semi-arid steppe (Martínez-Vilalta et al. 2014), dry arable fields (Martínez-Vilalta et al. 2014), artificial grassland sites (e.g., lawns, parks, road margins and sports fields) (Kushlan and Hancock 2005), flood-plains (Hancock and Kushlan 1984), freshwater swamps, rice-fields, wet pastures (Martínez-Vilalta et al. 2014), shallow marshes (Kushlan and Hancock 2005) and irrigated grasslands (with ponds, small impoundments, wells, canals, small rivers and streams) (Kushlan and Hancock 2005). It rarely occupies marine habitats or forested areas (Martínez-Vilalta et al. 2014). It occurs from sea-level up to c. 1,500 m (Kushlan and Hancock 2005). Its diet consists primarily of insects such as locusts, grasshoppers (Martínez-Vilalta et al. 2014), beetles, adult and larval Lepidoptera, Hemiptera, dragonflies (Hancock and Kushlan 1984) and centipedes but worms (Brown et al. 1982), spiders (Hancock and Kushlan 1984), crustaceans, frogs, tadpoles, molluscs, fish, lizards, small birds, rodents and vegetable matter may also be taken (Martínez-Vilalta et al. 2014). The nest is constructed of twigs and vegetation (Kushlan and Hancock 2005) and is positioned up to 20 m high in reedbeds (Kushlan and Hancock 2005, Martínez-Vilalta et al. 2014), marshes, dense thickets (Kushlan and Hancock 2005), bushes or trees (Kushlan and Hancock 2005), usually over or surrounded by water (Kushlan and Hancock 2005). The species nests colonially in single- or mixed-species groups with the nests placed close or touching (Snow and Perrins 1998).Habitats & Altitude

Habitat (level 1 - level 2) Importance OccurrenceArtificial/Aquatic - Irrigated Land (includes irrigation channels) suitable non-breedingArtificial/Terrestrial - Arable Land suitable breedingArtificial/Terrestrial - Pastureland major breedingArtificial/Terrestrial - Rural Gardens suitable non-breedingForest - Subtropical/Tropical Moist Lowland suitable passageGrassland - Subtropical/Tropical Seasonally Wet/Flooded major breedingWetlands (inland) - Permanent Freshwater Lakes (over ha) major breedingWetlands (inland) - Permanent Freshwater Lakes (over ha) major non-breedingWetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) major breedingWetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) major non-breedingAltitude max. 4080 m Occasional altitudinal limits

ThreatsLarge colonies nesting in urban areas are perceived as a public nuisance and may be persecuted (e.g. by disturbance to prevent colony establishment, removal or direct killing) (Kushlan and Hancock 2005). In its breeding range the species is threatened by wetland degradation and destruction such as lake drainage for irrigation and hydroelectric power production (Balian et al. 2002), and in some parts of its range it is susceptible to pesticide poisoning (organophosphates and carbamates) (Kwon et al. 2004).Threats & Impacts

Threat (level 1) Threat (level 2) Impact and StressesAgriculture & aquaculture

Agro-industry farming

Timing Scope Severity ImpactOngoing Majority (50-90%) Unknown Unknown

StressesEcosystem degradation

Biological resource use

Hunting & trapping terrestrial animals (persecution/control)

Timing Scope Severity ImpactOngoing Minority (<50%) Rapid Declines Medium Impact

StressesSpecies mortality

Climate change & severe weather

Droughts Timing Scope Severity ImpactOngoing Minority (<50%) Slow, Significant

DeclinesLow Impact

StressesEcosystem degradation

Threats & ImpactsThreat (level 1) Threat (level 2) Impact and Stresses

Energy production & mining

Renewable energy Timing Scope Severity ImpactOngoing Minority (<50%) Slow, Significant

DeclinesLow Impact

StressesEcosystem degradation

Natural system modifications

Abstraction of surface water (unknown use)

Timing Scope Severity ImpactOngoing Minority (<50%) Slow, Significant

DeclinesLow Impact

StressesEcosystem degradation

Pollution Herbicides and pesticides

Timing Scope Severity ImpactOngoing Minority (<50%) Slow, Significant

DeclinesLow Impact

StressesSpecies mortality

ConservationConservation Actions UnderwayThe species is not listed on priority lists of the Conventions.

Conservation Actions ProposedThe species can adversely affect the trees and bushes it uses for nesting, which may lead to the abandonment of the colony site if it is not managed (Kushlan and Hancock 2005). Freshwater habitats need to be sustainably managed. Establish non-intrusion zones around colonies.

BibliographyBalian, L.V., Ghasabian, M.G., Adamian, M.S. and Klem Jr, D. 2002. Changes in the waterbird community of the Lake Sevan-Lake Gilli area, Republic of Armenia: a case for restoration. Biological Conservation 106(2): 157-163.Brown, L.H., Urban, E.K. and Newman, K. 1982. The birds of Africa vol I. Academic Press, London.Hancock, J. and Kushlan, J. 1984. The herons handbook. Croom Helm, London.Kushlan, J. A. and Hancock, J. A. 2005. The herons. Oxford University Press, Oxford, U.K.Kwon, Y.K., Wee, S.H. and Kim, J.H. 2004. Pesticide Poisoning Events in Wild Birds in Korea from 1998 to 2002. Journal of Wildlife Diseases 40(4): 737-740.Marchant, S. and Higgins, P.J. 1990. Handbook of Australian, New Zealand and Antarctic birds, 1: ratites to ducks. Oxford University Press, Melbourne.Martínez-Vilalta, A., Motis, A. and Kirwan, G.M. 2014. Cattle Egret (Bubulcus ibis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. and de Juana, E. (eds.) 2014. Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/52697 on 15 April 2015).Snow, D.W. and Perrins, C.M. 1998. The Birds of the Western Palearctic vol. 1: Non-Passerines. Oxford University Press, Oxford.

Map (see overleaf)