Maybe it’s their large size, long neck, or stoic demeanor, but Gray Herons make me feel like I’ve time-traveled to the Jurassic period.
Latin name: Ardea cinerea | Japanese Name: アオサギ (aosagi)
Size: 90–98cm
Location: Gray Herons live year-round in many parts of Japan, South Asia, Western Europe, and Central and Southern Africa. They also migrate to Central Asia and Eastern Europe.
Diet: They hunt fish, eels, crustaceans, amphibians, molluscs, aquatic insects, small rodents, and even other little birds—like ducklings, Little Grebes, and Common Kingfishers.
Homelife dynamics: Gray Herons are colonial birds, which means they form large colonies amongst themselves and with other birds like them. Females do most of the nest-building on platforms high up in trees, while males gather materials such as sticks, reeds, and other plants. Young chicks are often unable to survive due to sibling competition and sometimes cannibalism during food shortages. Yikes.
Habitat: You’ll find them in ecosystems with tall trees for nesting and shallow waters for hunting. Satoyama ecosystems like the one in which my neighborhood is nested are a great place for them to live (more on that in a bit!). Arley and I regularly see them in the nearby ricefields where they hang out from mid-June to mid-August, when rice is growing and fields transform into buffets serving all their favorite food. When we first started spotting these birds, we wondered where they went when they left the ricefields. In a recent chat thread, a friend shared pictures of a huge flock nesting high up in trees!
A brief history of satoyama ecosystems in Japan
The Japanese archipelago slowly transitioned from a hunter-gatherer economy to an agricultural one around 2,400–3,000 years ago when rice cultivation was likely introduced from China and Korea. More than 70% of Japan is mountainous, so flat and easily settled land was scarce. Communities were required to develop land-management practices that resourcefully and sustainably utilized the forested hills and arable fields surrounding them.
These practices were further developed in the Edo Period (1603–1868), creating satoyama ecosystems characterized by a symbiotic relationship between nature and humans. (I’ve mentioned this in a previous post, but the term “satoyama” is made up of the Japanese characters for “village” (里) and “mountain” (山).) The forest provided a wealth of resources. From it came natural fertilizer for crops, forageable food and medicine, building materials, and fuel. In return, humans managed forests, grasslands, and rice paddies in ways that promoted biodiversity. Gray Herons, among many other animals, have flourished in Japan thanks to these satoyama ecosystems.
In the past 80 years, satoyama culture has slowly disappeared from the Japanese landscape, including where I live, because of industrialization and depopulation. In my city, many of these areas have been developed into suburban neighborhoods and shopping areas to attract families that commute into Tokyo for work. Thankfully, however, some areas continue to preserve small pockets of satoyama biospheres.
It’s only in the past few months that Arley and I have begun to educate ourselves about the importance of preserving the local satoyama in which our suburban neighborhood is nested. As we continue to learn, we’re looking for opportunities to participate in satoyama revitalization, to protect biodiversity, and to preserve the cultural heritage of this landscape.
For this post, we consulted Cornell Lab, an article in Science Direct, a post on Medium, and JTA’s Sightseeing Database.
i love this piece! the blue is so lovely against the heron! so majestic 🤩
Such an interesting history!