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Yellow-crowned Night Heron

A Yellow-crowned Night Heron stands and faces the left. It has a black and white face, a red eye, a dark beak, and gray-ish feathers from the neck down. Its legs are yellow-orange. It has plumes off the top of its head. In the background, mangroves can be seen. The bird stands amidst dappled shade and sunlight.

Yellow-crowned Night Herons like to hang out in mangroves, and they like to eat crabs.[1] They love crabs so much that when these birds were reintroduced to Bermuda, researchers found that over 90% of their observed diets of made up of crabs.[2] Insects, frogs, and fish are also on the menu, but it's clear crustaceans are their favorite food.[1]

With a name like "night heron," you might think that these birds are nocturnal. And you'd be close. They're primarily nocturnal, but they can also be found in the daytime.[3] Mangroves, cypress swamps, and rivers with forests nearby are all places they'll call home.[1, 3] Along the coast, the tides likely affect when they eat.[1]

At first glance, the hunting strategies of the Yellow-Crowned Night Herons might seem…well, let’s say relaxed. In one study, Rodgers observed the feeding behaviors of seven species of herons and noted that “the most sedentary forager was the Yellow-crowned Night-Heron, which spent over 80 % of its time engaged in non-locomotory foraging."[4] Its go-to strategies were primarily the “stand and wait” and “peering” methods (p.12). So, while Great Horned Owls swoop out of the sky to catch their prey and Yellow-bellied Sapsuckers drill for food,[1] the Yellow-Crowned Night Heron is over here like “Maybe I’ll just…wait.”

A Yellow-crowned Night Heron standing (maybe walking?) in mangroves. There are mangroves shoots in front of it as well as behind it. It faces the left. It is a shady area. It has a red eye, black and white face, and dark beak, with light plumes off the back of its head (ending a little below where the head meets the neck). Most of its feathers from its neck down are gray, with some darker gray feathers on its wings, and some black / dark gray looking feathers on the very back of its neck. Its legs are mostly hidden by mangroves, though a little bit of yellow can be seen.

Then there’s the Bermuda study mentioned above. With an abundance of land crabs on the island, the herons preferred the easy-to-catch crabs wandering on lawns and paths.[2] This was a win-win situation, since the residents had less property-damaging land crabs to worry about, and the birds got an easy meal. Can you blame them for wanting some fast food?

But sometimes these seemingly "relaxed" methods have a strategy that's really quite smart. In one report, Yellow-crowned Night Herons were observed staking out a commercial crayfish location.[5] Those birds stood by the crayfish burrows, where they positioned themselves so their shadows wouldn’t overlap the burrow entrances, waiting for the unsuspecting crayfish to emerge.

A Yellow-crowned Night Heron stands amidst branches and dirt and mangrove shoots. It has something in its beak. It faces the left.

Researchers have studied the bird’s diets and eating behaviors in many ways. One way is aided by a special ability. You see, Yellow-crowned Night Herons eat their meal and then regurgitate the indigestible parts. [6] (Great Horned Owls have a similar trick.)[7] Looking through bird barf is one way researchers have studied what Yellow-crowned Night Herons are eating.[6]

Yellow-crowned night herons look very different at different stages of their lives. It's one of my favorite things about them, mostly because of the juvenile Yellow-crowned Night Heron below:

A juvenile Yellow-Crowned Night Heron stands on one leg amidst the mangroves. It is brown with white flecks on the tips of some of its feathers and a dark beak.
Hey! This bird's been featured before!

A little fluffy. A little disheveled—like it just rolled out of bed. It makes me smile. 

I'm guessing this next bird in the picture below is a little older, since its doesn't have the small white spots on its wingtips that are typical of a juvenile.[8] The immature birds are mostly brown; it can take up to  4 years for them to gain their full adult appearance.[9] This one still looks quirky, with big red eyes and long yellow legs. 

A side-profile of an immature looking Yellow-Crowned Night Heron, facing the left. It has a red eye, a dark beak, and a mix of medium to dark brown wing feathers. Its neck feathers are mostly medium brown. Its head is a mix of streaky white and brown feathers. It stands upright, with its neck extended, without the hunched look of the juvenile heron in the previous two photos. It stands on the dirt in front of branches and mangroves. Orange-ish brown leaves are scattered on the dirt.

Finally, the adult birds have black and white faces with pretty plumes off the back of their head.

An adult yellow-crowned Night Heron stands with its back to the camera, showing off light gray wings that have streaks of dark gray. Its neck is a light gray, its head is black and white, and the nape of its neck is black. It has light colored plumes off the top of its head and a dark beak. It stands in front of mangroves. The ground it is standing on looks like it is at an angle--the bird is standing on higher ground. The area where it is standing has dappled sunlight, as opposed to the mangroves below it which are more shady.

All in all, the Yellow-crowned Night Heron is an interesting, crab-loving bird with some comparatively relaxed feeding methods. Sure, one of their methods for hunting is “stand and wait.”[4] But I too have sat on a dock with a fishing pole, bait in the water, watching the sun on the waves and waiting for a fish to bite.

This picture is shot at a lower angle. An adult Yellow-crowned Night Heron can be seen in the distance; the foreground is dirt with leaf litter. The bird stands amidst dappled sunlight and shade in front of mangroves. It faces the left.

The Details:

Common Name: Yellow-crowned Night Heron
Scientific Name: Nyctanassa violacea
Order: Pelecaniformes
Family: Ardeidae
Seen: Walking around mangroves.
Month: June 2024 (the first three photos and the last two photos), June 2023 (immature looking bird), and March 2023 (juvenile bird)
Range: In the United States, Yellow-Crowned Night Herons are found east of Texas. In states on the East Coast, their range extends as far north as parts of Maine.[10] Above Texas, they can be found as far north as parts of Minnesota and Wisconsin. However, in some states, they are only found during part of the year, such as during migration.
 

Outside of the U.S., they can also be found in the Caribbean Islands, Central America, and South America, especially along the coast.[10] The Cornell Lab of Ornithology's website has a very helpful range map.

Learn More:

  1. Kaufman, K. (1996). Lives of North American birds. Houghton Mifflin.  
  2. Wingate, D. B. (1982). Successful reintroduction of the Yellow-Crowned Night-Heron as a nesting resident on Bermuda. Colonial Waterbirds, 5, 104-115. https://doi.org/10.2307/1521041  
  3. Alsop, F. J. (2002). Birds of North America (American ed.). Dorling Kindersley Limited.  
  4.  Rodgers, J. A., Jr. (1984). Foraging behavior of seven species of herons in Tampa Bay, Florida. Colonial Waterbirds, 6, 11-23. https://doi.org/10.2307/1520962 
  5. King, D. T., & LeBlanc, D. (1995). Foraging behaviors of Snowy Egrets (Egretta thula) and Yellow-Crowned Night-Herons (Nyctanassa violacea) in South Louisiana. Colonial Waterbirds, 18(2), 224-225. https://doi.org/10.2307/1521486
  6. Riegner, M. F. (1982). The diet of Yellow-crowned Night-Herons in the eastern and southern United States. Colonial Waterbirds, 5, 173-176. https://doi.org/10.2307/1521050
  7. BirdNote. (2019, February 11). What is an owl pellet? Audubon. 
  8. Sibley, D. A. (2014). The Sibley guide to birds (2nd ed.). Alfred A. Knopf. 
  9. Cornell Lab of Ornithology. (n.d.). Yellow-crowned Night Heron: Identification. All About Birds.
  10.  Cornell Lab of Ornithology. (n.d.). Yellow-crowned Night Heron: Range map. All About Birds.


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