Observing this season’s new family of falcons at Futako, Louis Hindle is continuing the tradition that Mr. Van Den Bossche, a respected former faculty member of St. Mary’s International School, has started. Every year, Eurasian Kestrels have been using Futako Tamagawa as a breeding ground, finding a nest, hunting for food, and raising their chicks. This year, during the grade 8 Tama River Cleanup, run by St. Mary’s International School, the first sighting of a Kestrel entering a nest this season was made by Louis Hindle. Since then, there have been several more observations of the Eurasian Kestrel entering its nest.
It is resource intensive for birds to nurture a new generation of chicks, especially for Kestrels. Their average clutch size is around 3~6 eggs, and it takes weeks of constant incubation for these eggs to hatch. After they hatch, the chicks need to be well fed and protected from predators; larger raptors in the area, such as Goshawks and Peregrines, which have also been spotted at Futako fairly regularly. Most observations of Kestrels at Futako have been of them hunting for prey – they hover around 10 to 20 meters above the ground, perfectly stabilize their head, and use their incredibly sharp vision to spot their prey – rodents, lizards, insects, and other smaller birds. They are on the constant lookout for prey in the breeding season, so that they can keep their chicks and partners, who are incubating the chicks, alive. During such vulnerable and taxing times, Kestrels need a healthy environment where food is abundant to be able to find enough prey to sustain a healthy population. This makes them an important indicator species – their health depends heavily on the health of their ecosystem, making them a great indicator of the health of their ecosystem.
In an online interview with Mr. Van Den Bossche, he told us that he “first observed the Kestrels when I started to visit the area in the late 1990s”. The fact that Kestrels have been recorded in Setagaya since 1953 to this day, and have been seen breeding here annually at Hyogojima since 2005, according to the Setagaya Government Bird Census, tells us a lot about the biodiversity and health of Futako. There have been 210 species of birds recorded in Setagaya from 2016 to 2020, and countless other animals, such as rodents, insects, and mammals, have been instrumental in the ecosystem’s health. This is unique and fortunate, compared to other ecosystems in urban areas.
In an interview with Mr. Van Den Bossche, who has been observing the Kestrels in Futako for the past few years, said that the “Kestrels will tolerate humans if there is plenty of food and the rough grassland along the valley supports healthy populations of rodents”. Kestrels were especially willing to tolerate humans; the past few years, the Kestrels have decided to nest inside a highway bridge; right below a bustling highway, and above a park where locals visit daily to enjoy sports and other outdoor activities – and understandably, they are quite loud, and some stray frisbees have been observed hitting the bridge near where the nest is. The area has also been subject to a lot of construction over the past few decades, with bridges built, roads paved, and landscapes altered. According to Louis Hindle, in a pond in Hyogojima Park, “… in the winter, there are usually very few species … due to constant water drainage (for construction), making it an unstable environment for animals and birds alike”. But these birds have adapted and learned to survive in the concrete jungle. The Kestrels took advantage of the fact that the bridges provide an incredibly safe nest for their chicks, where other birds and mammals such as cats can’t get even close to. Similarly, Peregrine Falcons “returned as the construction began to slow down, with plenty of potential prey (pigeons and wildfowl) and building ledges to nest on and hunt from, again this is perfect habitat”. According to a fellow birdwatcher who agreed to a quick interview at the Futako Tama River, there is a Peregrine that often perches on a ledge near the top of the Rise building most of the time, staying clear of threats, while having access to a commanding view of its surroundings. According to Mr. Van Den Bossche, Futako’s environment “has recovered remarkably since the 1970s and should continue to support a rich biodiversity in the future with some management”. Mr. Van Den Bossche, Louis Hindle, and fellow birdwatcher Sora Miyazawa have confirmed that species that had disappeared due to construction, like the iconic Tanuki, have since returned to Futako as things settled down and pollution decreased.
However, not everything has been going well. First, animals such as the Eurasian Otter (a keystone species) that have disappeared because “the river was severely polluted with the onset of industrialization, probably some time during the twentieth century”, have yet to return. Invasive species compete with native species and alter habitats, which can negatively affect local ecosystems and can even lead to the extinction of native species. Sora Miyazawa said that one example is the North American Raccoon, which outcompetes the local Tanukis (the scientific name for Tanukis is the Japanese Raccoon Dog – but they aren’t actually raccoons, but instead a part of the canine family; something similar to a dog and a fox). Awareness and funding are incredibly important to keeping these ecosystems healthy – there needs to be more volunteer work, such as river cleanups, and campaigns to remove invasive species.
Eddie Lim is known for being a wildlife photographer, but not a lot of people know why he got into it. He used to think birdwatching was stupid and boring – “who cares about birds?”. That all changed during the 6th Grade Walkathon – he tried birdwatching, and it was surprisingly exciting, especially so because there was an abundance of raptors that day. He even saw the Peregrine Falcon, the fastest animal in the world, dive at an incredible 300 kilometers per hour, as fast as an F1 car. Point being, the Kestrels could act as a gateway drug for local residents to become fully invested in the local environment, just like it did for Eddie Lim. In Mr. van Den Bossche’s words, “birds of prey certainly are charismatic species and people are attracted to them”, and “any kind of environmental education is positive”. The chance to look at falcons nurture and hunt for their chicks every year, at a local park, is a great gift, privilege, and an opportunity to have people care about the planet that most people aren’t even aware of – when asked about people who come to Futako to watch the Kestrels hunt and mate, Louis Hindle said that “apart from the infrequent birdwatchers, it is rare to see a crowd”.
Previous efforts to raise awareness among local residents about the wonders and importance of the local environment have been successful, but at a minimal scale. When asked regarding the Tama River Study elective, which Mr. Van Den Bossche ran during his work at St. Mary’s, he said that it “raised a bit of awareness in the SMIS community, but I would have loved to have seen every student getting the opportunity. Such classes, though, depend on the school, and I don’t currently see the support for such programs.” – It’s rare to see any programs like he ran in any other schools, with such a successful effect, producing many dedicated birdwatchers. Currently, a non-profit organization called Setagaya Mizube Design is doing work to educate people about nature, by gathering volunteers both young and old, running river cleanups, creating habitats for local fish, and doing scientific field investigations which included cooperation with the Tokyo City University, and the recording of invasive plant species (at the time of publication of this article, they have not yet responded to my interview request, for further details and direct statements). However, not enough is being done to fully educate people about the importance of nature. A prime location to start more work to create more environmentally aware communities is St. Mary’s International School. It has the blessing of having a thriving ecosystem within walking distance, and its alumni are often in a privileged position and often become influential leaders in modern society. Properly educating these students from an early age will result in leaders in the future who are focused on caring for our environment.
All pictures are by Eddie Lim. Thank you to Mr. Van Den Bossche, Louis Hindle, and Sora Miyazawa to agreeing to an interview
