subbuteo

I flew into Shenzen airport yesterday and was alarmed to see what looked like mist nets along the length of the runways.  Obviously, they were difficult to see but there were evenly spaced posts and between dark bundles suspended of various sizes- typical of mist nets I have seen in fields in HK.  I know bird strikes are a serious issue for aircraft but this seems "overkill".  I cannot say with certainty that there were mist nets so would be grateful if others could look out and check if leaving/arriving.  However, the toll of birds must be huge if there are nets over hundreds of metres long.  Could HKBWS lobby for their removal if their presence is confirmed?

Dylan

PS I should add that I was at several other airports over the past ten days in Xinjiang and Hunan and did not see nets like this.

[ Last edited by subbuteo at 11/04/2012 13:00 ]

sdavid

You're right Dylan, they are mist nets. Apparently they are widely used across China as a control measure. I've seen them at several airports in recent years but there must be more appropriate control measures that can be implemented.

subbuteo

I thought so- dreadful.  There were at least a hundred bundles (of birds and probably bats) that I saw dead in the nets- I could see where a flock of small birds had become entangled together- one silhouette looked like a small falcon.  Presumably to be "effective" they are cleared regularly so must account for a great number of birds each year.  

I agree that there must be more effective measures, I've never seen them at any other airport.

Dylan

Dragonfly

Hi Dylan,

I work in aviation and you're unfortunately right on the mark - these are mist nets and they're commonplace at most of the Mainland airports I visit regularly.

Good luck with lobbying for improvements - Chinese aviation, and everything related to it, is run more or less purely by the military and no-one stand a chance to change, or rather improve, the terrible state things are in. Not even the International Civil Aviation Organization, ICAO, seems to have much power.

Although birdstrikes are potentially dangerous, there's plenty of ways to deal with "threats" from birds in a much more humane way. We see that all over the rest of the world.
Not many years ago in Beijing some poor old bloke was walking up and down the runways all day hitting a big gong gong - not only was this quite a charming, very oriental, take on bird-scaring, it was also good for our feathered friends (although I feel sorry for the poor guy too!).

It's not easy to change the world, but it doesn't hurt to give it a try.

All the best, also to the passerines going through Shenzen airspace(!),
Morten

Dragonfly

I forgot to mention that from where I'm sitting, I don't see that many bats/birds caught in the nets, although this could be down to the fact that there's regular patrolling of the nets at some of the airports.
However, the poor birds being caught in the nets probably won't be released again if removed from the nets - if they're luckily still alive.
Morten

subbuteo

Thanks, Morten.

I came in in the late afternoon so perhaps the nets hadn't been cleared yet- I assumed the birds were dead as is usually the case in fields here.  It is nice to imagine the birds are removed, given a pat on the head and set free.  I doubt it too.

I don't know where to begin to get something done.  I don't hold much hope but it would be worth a try.

Dylan

cgeoff

Setting the birds free is certainly not the aim, as you say Dylan. Mist nets are used all over China for bird control, and probably at other airports in countries where it is considered there is not the money to implement more effective techniques. I have worked in this field since the mid-1990s, and have not seen any decline in their use in China during that period.

While mist nets may reduce numbers of certain species such as pipits, larks, wagtails and smaller waders, in many cases it does very little to impact the real problem species. For example, where a problem species is something like Black Kite, mist nets would do nothing to impact numbers and thus the bird strike risk. In general, it is large and/or flocking species that are the key issues at airports worldwide, as the potential for damage to engines is greatest from these birds. Mist nets are unlikely to do anything to control their numbers, except perhaps via the indirect impact on their prey species. But this is not likely to be significant. Control of smaller species is best done via habitat management.

Unfortunately, airports, who pay for bird control, want to do it as cheaply as possible. However, it is airlines that pay for the effects of bird strikes. Until this dichotomy is addressed, many airports will do the minimum possible. Although one would anticipate the legal process should close the loop, in many cases it does not.

Incidentally, HK International Airport does not use mist nets - you will be relieved to hear!

GeoffC

HKBWS Chuan

Document from HKIA said that they use means including "habitat management, environmental hygiene" and "bird distress calls and ultrasonic repellers".
They have an officer equipped with rifles and he was on a TV programme some years ago.
http://www.hongkongairport.com/e ... eld_and_Systems.pdf

HKBWS could try to raise this concern, would members (if possible) please take photographs when you visit Shenzhen Airport.