Gray heron

Gray herons mostly eat fish.

They stand still and wait. Then they grab a fish with their beak.

Gray herons eat mostly fish and eels, usually 10 to 25 centimeters long. They also catch amphibians, crabs, insects that live in water, snakes, small rodents and small birds.

A heron often stands as still as a statue in shallow water, waiting for its next meal to swim by. It usually feeds alone, but where there is a lot of food, many herons may gather. Herons feed at any time of day or night, most of all at dawn and dusk.

The IUCN gives a diet dominated by fish and eels 10 to 25 centimeters long, plus amphibians, crabs, molluscs, other crustaceans, aquatic insects, snakes, small rodents, small birds and plant matter (which may be incidental, or only help form pellets) (Brown et al. 1982, Snow and Perrins 1998, Kushlan and Hancock 2005). It is typically a solitary feeder, but large groups may gather at rich temporary food sources or where feeding areas are limited. It feeds day or night but is most active at dawn and dusk, roosting communally or alone in the middle of the day and at night.

The Shropshire Wildlife Trust describes herons waiting motionless in shallow water for prey to swim by, occasionally taking a mole, and visiting garden ponds.

Gray herons often feed alone.

But at nesting time, many come together in the treetops.

Gray herons spend most of their time alone, but they gather in heronries to nest. Some heronries have been used for many decades. Herons also rest together or alone in trees, on cliffs and along shores.

In the UK, herons' nests have been counted since 1928 in the BTO's Heronries Census. Herons that migrate travel mostly at night, in small groups or flocks of up to 250 birds.

The BTO notes that some heronries have been occupied for many decades and that UK heronries have been monitored since 1928 through the Heronries Census. Herons roost communally or alone in trees and on cliffs, rocks, islets or shores (IUCN).

Palearctic birds disperse widely in September and October and return in February; most movements are nocturnal, in small parties or flocks of 200 to 250 (Brown et al. 1982). The BTO's ringing data give a typical life expectancy of about 5 years for a bird that reaches breeding age (adult survival about 0.73 a year), and the oldest ringed heron was 23 years, 9 months and 2 days old (2003). The Shropshire Wildlife Trust also gives an average lifespan of 5 years.

There are lots of gray herons.

People count their nests to see how they are doing.

The gray heron is listed as least concern. There may be 500,000 to 2.5 million adults in the world.

In the past, people in Europe killed many herons because they ate fish that fishers wanted. Today, cutting down the trees where herons nest is a problem in many places, and bird diseases could be a threat. In the UK, herons were more common in the early 2000s than at any time in 90 years, though numbers have dipped since.

BirdLife International assessed Ardea cinerea as Least Concern for the IUCN Red List (assessed 13 August 2019, published 2019): trend unknown; about 790,000 to 3.7 million individuals (Wetlands International 2015), roughly 500,000 to 2.5 million mature birds; Europe holds 223,000 to 391,000 pairs.

The IUCN notes heavy persecution in nineteenth-century Europe because herons competed with fishers and fish farmers; killing at fish farms has not reduced the global population so far. Timber harvesting removes or disturbs nesting trees across much of the range, renewed hunting threatens Bavarian birds after hard winters, the Madagascar population is vulnerable, and avian influenza and avian botulism could threaten it in future. The BTO's Heronries Census found a record of more than 10,441 nests in 2003, but fewer in the 2018 survey; numbers have increased across Europe since 1980 (PECBMS 2020, cited by the BTO).

Listen to the sound at the start of this page.

It is a real heron family at its nest in England.

At the start of this page you can play a real recording of a gray heron family at its nest. It was made beside a lake at Shearwater, near Warminster in Wiltshire, England, on 5 June 1992, and is kept by the British Library.

You can hear cracking sounds, retching notes and bill-snapping.

The recording on this page was made by Howard Phelps at Shearwater, near Warminster, Wiltshire, England, on 5 June 1992 (British Library, shared on Wikimedia Commons). Its notes describe cracking sounds, retching notes and bill-snapping from a family of gray herons at a nest on a lake edge.