Red-crowned Cranes on Hokkaido

The Red-crowned Crane is listed as Vulnerable, with an estimated 3000 individuals in 2009. Some populations – especially the Hokkaido one – seem to be doing quite well. On Hokkaido, the number rose from 33 in 1952 to about 1200 now, with the bird presumably benefiting from its symbolic importance for Japanese culture and its pull for tourists. Still, one source states that this is the second-rarest of all crane species.

What methods are effective to protect an endangered crane species? An interesting paper compares two different strategies, habitat management (as done in the US for the Whooping Crane) and artificial feeding in the leanest periods (as done in Japan for the Red-crowned Crane). Conclusion: the Japanese method seems to work better (of course, couched in the usual careful scientific phrases): “An initial review of these two case studies reveals indications that artificial feeding in periods of lean food availability resulted in much faster overall population recovery in Japan”.

An ex-girlfriend of mine once said, “Dancing is like sex. If it feels really good, it does not matter how it looks like”. I imagine that Red-crowned Cranes fully agree with this statement.

Here is a description of their dance from a website: “Red-crowned cranes use their courtship dance, which consists of bowing, head bobbing and leaping in order to communicate with each other. The dance is very beautiful and strengthens the bond between male and female pairs.”

Here we go again – “strengthening the pair bond”, the old explanation that does not really explain anything. And also: “very beautiful” – to me the dancing cranes look more like a bunch of punks at a UK Subs concert than classical ballet dancers.

Other individuals seem to have seen Saturday Night Fever a few times too often and now think they are John Travolta.

And now for something completely different (Monty Python). It seems that the market for crane pornography is rather limited despite the lack of any legal obstacles to its distribution. The most likely reason is that it is just not that attractive to watch – clumsy rather than graceful, labored rather than sexy.

One study makes one rather weird and disturbing observation – in China, the number of captive birds has risen faster than can be explained by the breeding of captive birds (more than 1500) alone. So, the likely reason is that wild birds were captured and added to the captive population, which is not quite what species protection should be about (particularly as other efforts for this species often go in the opposite direction, i.e., captively bred birds are released into the wild).

And yes, captive and wild cranes are not the same – they have different gut microbiota (source). Is this relevant? The authors of the study think it is (maybe they need more grants): “Comparing the differences in gut microbiota function and composition of captive and semi-free-range red-crowned cranes is critical for conservation management and policy-making”. As usual, they forgot world peace as a key argument.

Red-crowned Cranes have a misogynistic streak in them – they mainly feed on female rather than male crabs, even though the female crabs are smaller. The cranes defend this preference by pointing out that the female crabs offer a higher-energy reserve ratio, i.e., are more nutritious relative to their mass (source: HBW).

Life of a Red-crowned Crane can be difficult. On the one hand, in reserves such as the one at Yancheng, China there are disturbances from humans, particularly in the non-core areas of the reserve (source). This means there is more need for watching and thus less time for foraging. On the other hand, in the center of the reserve, where there is less disturbance from humans, there is a greater need for vigilance due to fights with other cranes. Damned if you do, damned if you don’t.

It must be quite unpleasant to be a single crane, as the coupled individuals constantly shout out about their companionship. Would be much nicer to shut up – this just puts pressure on the single cranes.

In the longer run, China may not have to worry too much about its wild Red-crowned Cranes – one study by Chinese authors suggests that due to climate change, the breeding range of the continental population will shift northward over this century and will also change the country owning the largest portion of breeding range from China to Russia, ending with the statement that “Russia should take more responsibility to preserve this endangered species in the future.”

The Red-crowned Cranes at the Hokkaido winter feeding spots have solved the problem by just ignoring humans completely, which sounds nice for photographers but actually makes life difficult if you only bring an 800 mm lens … (this is the rare occasion of my post giving some vaguely useful practical tips).

Interestingly – and slightly counterintuitive – Red-Crowned Cranes may benefit from reed cutting. One study found that the cranes prefer those areas where reed has been cut over those uncut ones.

Apparently, cranes (not specifically Red-crowned ones though) are mentioned twice in the Bible: once on account of its voice (Isaiah 38:14: “Like a swallow or a crane, so did I chatter”). To give you the other mention would require me to subscribe to www.biblestudytools.com, which – given that it would cost about 50 USD for an annual subscription and that my interest in studying the bible is rather limited – is not really an option for me.

In 2003, China’s State Forestry Administration submitted the opinion that “the Red-Crowned Crane is the national bird ” to the State Council, but this was rejected because the scientific name of the Red-Crowned Crane is “Japanese Crane”. There is a slightly paradoxical lesson here – if you want to become a national bird, do not align too closely with a nation.

The importance of cranes in Chinese mythology is also reflected by the saying “Riding a crane to the west”, which is a euphemism for death – it means riding a crane and flying to heaven (not to Japan).

This goes as far as some Chinese websites mythologizing the Red-crowned Crane up to the point where it gets fairly absurd (machine translation from Mandarin Chinese): “They are monogamous birds and will only have one mate in their life. When one of the couple dies unfortunately, the other will spend his life infatuated and lonely and eventually die.” Evolution generally disfavors such romantic attitudes toward life.

At least the same website refutes the claim – apparently sometimes made in China – that the red blood and feathers of the crane’s head are toxic and were in the past used by some emperors to kill their least favorite ministers. In fact, they used arsenic trioxide (source) which is red due to some impurities.

Photographers sometimes have a chip on their shoulders as not too many people take them seriously as artists (me neither). So, to demonstrate their artistic spirit, they create fake art such as the “artistic” crane photos shown below.