Jennifer:
Hey Adam, are you ready to compare notes for our presentation on pigeons for next week?
Adam:
I found some really good sources describing all the different kinds of pigeons for the background section.
Jennifer:
I knew they were a common bird but didn't realise there were so many types.
Jennifer:
I found an interesting new study on the Australian Crested Pigeon.
Jennifer:
It makes a special sound to warn the rest of the flock of danger.
Adam:
But a lot of birds use calls or songs to find a mate or to sound the alarm.
Adam:
What's special about this one?
Jennifer:
Well it uses its wings.
Jennifer:
Yes, if the pigeon is startled it makes a whistling sound when it flies off.
Jennifer:
This sound warns other pigeons in the flock that there's danger.
Adam:
I found a lot of stuff on the Rock Pigeons.
Adam:
They're the ones with the widest distribution.
Jennifer:
Of all the pigeon species, they've been the most successful at adapting to different environments, haven't they?
Jennifer:
In contrast to the Rock Pigeon, there's a pigeon in the north of Australia, the Black Banded Pigeon, which is restricted to one very small patch of forest.
Jennifer:
Another interesting thing about it is that unlike the typical pigeons we see on pavements and roads, it stays way up in the trees in the rainforest.
Adam:
They're varied in terms of diet as well.
Adam:
The Galapagos Pigeon, for example, gets all its nutrients from this one kind of cactus that grows on the island where it lives.
Jennifer:
So is there anything that pigeons can't eat?
Adam:
They should stay away from meat because it contains bacteria that is dangerous to them.
Jennifer:
You know, I thought pigeons all looked the same, but their plumage is really variable too.
Jennifer:
The Nicobar Pigeon from Indonesia is very attractive.
Jennifer:
It has beautiful metallic green feathers.
Adam:
It's a wonder they're not hunted.
Jennifer:
Now, in the second part of our presentation, we plan to look at why pigeons are seen as pests nowadays and what is being done to control them.
Jennifer:
A lot of people in the city like to feed pigeons, don't they?
Adam:
Some people think that it's kind, but in fact, it's not a good idea.
Jennifer:
I suppose human food isn't very healthy for birds, especially fast food.
Adam:
Actually, because the pigeons don't have to spend time looking for food, they have more time to mate and reproduce, and so it results in population explosion.
Jennifer:
So the city becomes absolutely overrun by pigeons.
Jennifer:
That's bad for the city and for the pigeons.
Jennifer:
Now, I read that here in Melbourne, we have a pigeon problem in the centre of the city and the city council is trying to deal with it.
Adam:
Yes, they've built some special nesting places in one of the parks in the city centre.
Adam:
They're designed to house the pigeons so they stop creating nests on buildings.
Jennifer:
But isn't that just changing the location of the problem?
Adam:
Well, that's just the first step.
Adam:
In the second stage of the council scheme, they exchange the pigeon eggs for dummy eggs.
Adam:
It's like a form of birth control.
Jennifer:
A very elaborate one.
Jennifer:
Someone would have to go in and replace those eggs by hand.
Adam:
The program does work as a means of controlling the population, but the financial burden on the taxpayer is quite high.
Jennifer:
Yes, I imagine it would be.
Adam:
The most successful pigeon control program in recent times was in Basel in Switzerland.
Jennifer:
And what did they do?
Adam:
Well, the city council found that teaching the public about the negative effects of feeding pigeons was more effective than trapping the pigeons or providing alternative nesting sites for them.
Adam:
These were both methods they'd tried previously.
Jennifer:
We'll have to include that finding.
Jennifer:
Do you think we've got enough for our presentation or should we do more research?
Adam:
Well, I was thinking that we should also make it clear to the audience why pigeons in cities are undesirable.
Jennifer:
Yes, we haven't really done that yet.
Adam:
Right, I've got some information on the damage their droppings do to buildings.
Jennifer:
And I've got something related to that on how their feathers can block gutters and pipes causing water damage.
Adam:
But I haven't found anything yet on the health risks to humans that urban pigeons pose.
Jennifer:
Neither have I.
Adam:
Okay, can we meet again tomorrow in the computer lab?
