Where are all the birds in Japan? (1 Viewer)

[BigBadTrevsy]

Hi everyone, and particularly anyone in Japan who can help with this question. We've just returned from a fabulous honeymoon to Tokyo, Okayama, Hiroshima, Kyoto and Hakone in Japan, which was mostly cultural and city based. It was a fabulous trip and we hope to visit this wonderful country again.

But, I was very struck by how few birds we saw, particularly in terms of overall diversity. Looking out at my ordinary UK garden on the edge of London, UK today, I can easily see 20 species in an hour without too much difficulty. But in Japan, over two weeks, I only saw about 20 species in all with casual looking in large parks, temple gardens and forested areas. The vast majority of those were confined to just a handful of species: large-billed crow, brown eared bulbul, spot-billed duck, black kite, warbling white-eye, long-tailed tit, grey heron, Japanese cormorant. Occasionally, from the bullet train, I might glimpse a modest aggregation of egrets on the edge of a river and one highlight was a huge murmuration of white-cheeked starlings roosting next to Okayama station (whose calls echoed throughout the subway and mall below ground).

Compared to western Europe and many other places that I have visited, though, the density and frequency of birds seemed to be very low. My question is: why? Japan has more than 700 species (more than the UK I think), but where are they and why are they so difficult to see? My thoughts about the possible causes are: in early winter, many species have migrated elsewhere; in cities, the landscape is highly manicured and intensively managed, with little space for insects and weeds to sustain larger numbers of birds; cold winters can reduce bird densities generally; many birds could be forest species which are hard to see even in their habitats; birds might be persecuted.

I would be very interested in anyone's thoughts one why we saw so little, both in diversity and quantity. Thanks everyone.

 

[Andrew Whitehouse]

It's a good question and is a striking feature of Japan. I'll make a few points that I think are worth keeping in mind.

I agree that it's hard to see a wide variety of species in Japan in a short period of time, although travelling around the country yields a much better list. Although in some ways Japan is geographically comparable to Britain, there's a much wider range of biomes, from basically Siberian Taiga in Hokkaido and the mountains of Honshu, through temperate forests to subtropical islands in the south.

I think the most species I've seen in one place in a day in Japan is around 50 species, actually at Kasai-Rinkai Park in Tokyo in winter. I can easily see more than that around where I live in Scotland in a few hours, almost any time of the year.

In terrestrial environments in Japan, there usually aren't large numbers of birds anywhere. Freshwater habitats in winter are still quite good with large numbers of waterfowl in the right places. Coastal and marine environments can be absolutely rammed with birds.

I'm not sure exactly why terrestrial environments in Japan are so lacking in birds (although there are still some brilliant birds around). Your points about intensive management are probably a factor, although to an extent are true of the UK too.

 

[kb57]

From my more limited time in Japan I'd agree with everything Andrew says - the point about terrestrial habitats in the boreal zone emptying out in winter is very true too. Hokkaido in winter is comparable to Canada - you can walk through a forest and literally see or hear nothing (well, I think I had one Japanese tit in birchwood habitat at Kushiro Shitsugen National Park...). At the same time, the seas off the Notsuke peninsula were crowded with sea duck like Stejneger's scoter at densities you might only start to approach in parts of the Firth of Forth.
I don't think persecution is an issue there - in fact the opposite may be true, there may be more mammalian bird predators around, including mustelids like Japanese sable, and certainly red foxes are very common and apparently unmolested in Hokkaido.

 

[Larry Sweetland]

Are you sure about Japanese Cormorant? Asking because I'm interested in going to Japan and was under the impression that it was a difficult bird to see (and identify), and greatly outnumbered by Great Cormorant, even at the sites where it's found.

 

[Andrew Whitehouse]

Something to keep in mind with the forest habitats is that forests in Japan are often more extensive and wild than forests in the UK. UK forests tend to have a lot of edge habitats, which have quite high bird densities. My experience around the world in temperate and boreal forests that are quite wild and extensive is that it's often very hard to see a lot of birds quickly. Densities are low and, although variety can be quite high, it takes a long time to see everything that's there.

 

[kb57]

Are you sure about Japanese Cormorant? Asking because I'm interested in going to Japan and was under the impression that it was a difficult bird to see (and identify), and greatly outnumbered by Great Cormorant, even at the sites where it's found.

I believe the identity of the OPs observations depends on habitat.
It's certainly true around Tokyo that great cormorant is common and the default species, but Japanese cormorant is more likely on rocky coasts, and particularly more likely further north. I only had one Japanese cormorant I was able to get a close enough look at and positively ID, and that was on Miyake-jima (an immature on a lake, not a rocky coastal habitat...). There are also pelagic cormorants in Hokkaido in winter - saw a few in harbours.

 

[BigBadTrevsy]

Are you sure about Japanese Cormorant? Asking because I'm interested in going to Japan and was under the impression that it was a difficult bird to see (and identify), and greatly outnumbered by Great Cormorant, even at the sites where it's found.

No, I'm not. Thanks for flagging that - sounds like it was Great Cormorant! That's what happens when you refer to a simple bird list for Japan online without doing proper homework.

 

[BigBadTrevsy]

From my more limited time in Japan I'd agree with everything Andrew says - the point about terrestrial habitats in the boreal zone emptying out in winter is very true too. Hokkaido in winter is comparable to Canada - you can walk through a forest and literally see or hear nothing (well, I think I had one Japanese tit in birchwood habitat at Kushiro Shitsugen National Park...). At the same time, the seas off the Notsuke peninsula were crowded with sea duck like Stejneger's scoter at densities you might only start to approach in parts of the Firth of Forth.
I don't think persecution is an issue there - in fact the opposite may be true, there may be more mammalian bird predators around, including mustelids like Japanese sable, and certainly red foxes are very common and apparently unmolested in Hokkaido.

That reminds me of a science news story many years ago, which I think said that the Bialowieza Forest in Poland had lower densities of birds in part due to the high proportion of dead trees compared to managed forests. This apparently means that while food is not a limiting factor, heavy brood predation is. I found this summary article along the same lines: https://www.researchgate.net/public...n_the_Bialowieza_Forest_a_40-year_perspective

 

[Andrew Whitehouse]

That reminds me of a science news story many years ago, which I think said that the Bialowieza Forest in Poland had lower densities of birds in part due to the high proportion of dead trees compared to managed forests. This apparently means that while food is not a limiting factor, heavy brood predation is. I found this summary article along the same lines: https://www.researchgate.net/public...n_the_Bialowieza_Forest_a_40-year_perspective

Yes and Bialowieza, like most primary forest, is quite hard work for birding and you generally see relatively few birds compared to e.g. a small British wood or park. The rewards are great for those who persist though. Most of the more extensive Japanese forests are similar.

 

[jogresh]

That reminds me of a science news story many years ago, which I think said that the Bialowieza Forest in Poland had lower densities of birds in part due to the high proportion of dead trees compared to managed forests. This apparently means that while food is not a limiting factor, heavy brood predation is. I found this summary article along the same lines: https://www.researchgate.net/public...n_the_Bialowieza_Forest_a_40-year_perspective

Very interesting indeed, cheers. Fascinating to read about the negative correlation between high mouse numbers, and low Wood Warbler numbers/success. 🤔🧐