ajohn

It is often not a problem when people are close to birds nests or young birds. As tomoatofamily mentions, birds breeding in urban parks often have large numbers of people nearby. However, the great majority of these people walk straight past the nest or baby - the adult can sit nearby for a short time and then return to feed the chick or shelter the eggs. This does not make the chicks 'stronger and more able to survive', it is just that they become less scared by the presence of people.

The problem is that it is often very difficult to judge when you are causing disturbance. Imagine you see a nest or a chick and go closer to take a look. Maybe you don't notice the adult nearby, so you spend a lot of time near a chick - all the time the adult is sitting close by with food that it does not bring to the chick - if this happens too often the chick will not get enough food to survive. Maybe you have not noticed that there is a cat or a bird of prey nearby - as you go to the nest or chick, the predator watches you, and then knows exactly where to go to eat the chick.

Often the presence of people near breeding birds is not a problem, but sometimes it can be a disaster for the birds. It is always in the best interest of the bird that people spend as little time as possible close to breeding birds. For this reason, I recommend that you do not attempt to photograph nests or chicks.
EricB recently posted details of a recent code of conduct for bird photography which provides advice to minimise disturbance. Check this link: http://www.hkbws.org.hk/BBS/view ... &extra=page%3D1

ajohn

To make it clear, I am not saying that all human activity around nests is a problem. But I am aware that there are many members of the society and many visitors to this forum who are new to bird watching and may not understand how their behaviour affects birds. Also, with little experience they may not be able to recognise the normal behaviour of a particular species, in which case they may not know whether they are causng disturbance i.e. they can't recognise the 'safe distance'. In my experience, birds around nests are often disturbed at a much greater distance than you expect (I have seen adult birds nervous to visit a nest when I have been hidden in vegetation at a distance of over 50m). It is for this reason that I am always so keen to remind people of the possible disturbance that they may cause around nests - OK, some people on this forum do have the experience to know when there is a problem, but many don't.

As for nests photography, a single photograph of a nest where the adults are habituated to the presence of people is unlikely to be a problem. Spending a long time close to a nest probably will cause a problem. Again, many people are new to the hobby and don't know where the dividing line will be. For this reason I try to remind everyone not to take photos of nests.

Personally I think the problem is made worse by posting pictures of nests on a public forum, so that all readers see the pictures and think 'If they can take the photo, that means it will be OK for me to take a photo as well.' I therefore think that there should be no photos of nests posted onto a public forum such as this, and I have publicly stated this on a number of occasions. And for the record, this includes the 'Home Sweet Home' forum, which I personally think sets a bad example for new birdwatchers and I have not liked since it started a year or two ago.