Least bittern

Ixobrychus exilis

Photo by Harold Stiver (Nature Notes)

Common name:
least bittern (en); socoí-vermelho (pt); petit blongios (fr); avetorillo panamericano (es); Amerikanische zwergdommel (de)

Taxonomy:
Order Ciconiiformes
Family Ardeidae

Range:
This species is found from south-eastern Canada and the eastern, southern and south-western United States, through Central America and into the coasts and along the main rivers and wetlands of South America as far south as south-eastern Brazil and Paraguay. The populations in North America migrate south to winter in Central America.

Size:
These birds are 28-36 cm long and have a wingspan of 41-46 cm. They weigh 50-110 g.

Habitat:
The least bittern is found in a wide range of coastal and inland wetlands, including saltmarshes, mangroves, fresh water marshes and swamps, lakes with dense vegetation, rivers and artificial channels and ditches. They are present from sea level up to an altitude of 3.100 m.

Diet:
They mainly feed on small fishes, crustaceans and aquatic insects, but also amphibians, reptiles and terrestrial insects. They can also eat the eggs and chicks of other marsh-dwelling birds.

Breeding:
Least bitterns are loosely colonial. The male builds the nest, which consists of a frail platform of sticks and twigs, placed over water on dead stalks of emergent vegetation. There the female lays 2-5 bluish-white eggs with brown flecks, which are incubated by both parents for 19-20 days. The chicks are fed by both parents and fledge about 25 days after hatching. Each pair can raise 1-2 broods per season.

Conservation:
IUCN status - LC (Least Concern)
This species has a very large breeding range. There is no information regarding population size or global trends, but some populations are known to be in decline, due to habitat loss caused by drainage of wetlands and human disturbance during the nesting period. In North America the least bittern has had a stable trend over the last 4 decades.

Chinese egret

Egretta eulophotes

Photo by Tim Edelsten (Birds Korea)

Common name:
Chinese egret (en); garça-chinesa (pt); aigrette de Chine (fr); garceta china (es); schneereiher (de)

Taxonomy:
Order Ciconiiformes
Family Ardeidae

Range:
These birds breed in small islands off the coasts of South Korea, North Korea and across the border into north-eastern China and south-eastern Russia. They migrate south to winter in Vietnam, the Philippines, Malaysia and northern Indonesia.

Size:
The Chinese egret is 65-68 cm long and has a wingspan of 97-114 cm. They weigh 450-500 g.

Habitat:
They are mostly found in coastal areas such as estuaries, bays and offshore islands, along mangroves, mudflats and rocky shores. They are also found in rice fields and aquaculture ponds.

Diet:
Chinese egrets feed on fish, small crabs and other crustaceans, worms, insects, small aquatic invertebrates, amphibians and small reptiles.

Breeding:
These birds breed in April-July. They form breeding colonies in offshore islands, with each pair building a disc-shaped nest made of straws and sticks, lined with grasses. The nests are typically placed on trees, 12-18 m above the ground, or sometimes in lower trees or scrubs. The female lays 3-5 pale blue-green eggs, which she mostly incubates alone for 24-35 days. The chicks are fed by both parents and fledge 36-40 days after hatching.

Conservation:
IUCN status - VU (Vulnerable)
The Chinese egret has a relatively large breeding range, but the global population is estimated at just 2.500-10.000 individuals. The population is suspected to be declining by 20% per decade due to habitat loss and degradation through reclamation of tidal flats, estuarine habitats and uninhabited offshore breeding islands for infrastructure, industry, aquaculture and agriculture. Pollution and disturbance of the breeding colonies are two additional problems.

Rufescent tiger-heron

Tigrisoma lineatum

Photo by Alejandro Tabini (Birding Peru)

Common name:

rufescent tiger-heron (en); socó-boi (pt); onoré rayé (fr); hocó colorado (es); marmorreiher (de)

Taxonomy:

Order Ciconiiformes

Family Ardeidae

Range:

These birds are found from southern Guatemala down to Ecuador, Brazil, northern Uruguay and north-eastern Argentina.

Size:

They are 66-76 cm long and weigh 800-900 g.

Habitat:

Rufescent tiger-herons are found in a wide range of inland wetlands, including bogs, marshes, rivers, lakes, swamps, fens and peatlands, but also in mangroves and swamp forests. They are present from sea level up to an altitude of 1.000 m.

Diet:

They mostly forage at dusk and night, feeding on fishes, amphibians, reptiles and insects including grasshoppers, water beetles and dragonfly larvae.

Breeding:

Rufescent tiger-herons build solitary nests in tall trees, consisting of large platforms of sticks. There the female lays 2-3 eggs which she incubates alone for 31-34 days. The chicks are fed by both parents and fledge 4-5 weeks after hatching.

Conservation:

IUCN status - LC (Least concern)

This species has an extremely large breeding range and is described as common, at least in Brazil. The population trend is difficult to determine because of uncertainty over the impacts of habitat modification on population sizes, but overall it is not considered threatened at present.