Passerines as a natural biological pest control - sources (not only) for university thesis

  • It would be great if we could sort out the Box-moth caterpillars too, but apparantly they don't taste so good, or maybe their colours are repugnant. Or maybe because they aren't local, the birds are suspicious of eating them. They do eat the adults though.

    Best wishes

    Hazel in the Gironde estuary, France

  • @Dave:

    Heh, I was accompanying professional ornithologist while he was trying to catch the Wryneck. 30 minutes from two meters - I still hear the little beast in my ears :)

    Thank you for your help and your contact!

    @PB:

    I believe it is good to ask such questions - I'll try to explain it on an example: Modern forests (at least in my country) are changed by a man becose their main goal is to provide us with as much wood as possible. However its uniformity creates perfect banquet for pests - and due to very convenient conditions (lots of food + no enemies) the pests begin to reproduce quickly and can damage the trees. Forester has two options 1) leave it be and let the hungry pests decimate the forest 2) use chemicals, but due to their untargeted application they probably kill most of the insects in the area. Side effect are also the costs and possibility of some unhealthy residuals. Plus it is a neverending circle - becose the forest is not able to defend itself and the pests will return again and again...

    Biological control is trying to restore balance between predators and prey as a natural control mechanism*. Supporting natural predators for sure may create loses also in population of "good" insects. But smaller than chemicals. Generaly birds as any predators never totaly decimate their prey (they better leave the area instead of chasing after the last bug). And insect are ready to reproduce rapidly to make up their (natural) losses. My goal is basically to "repair" man-made forest ecosystem by nestboxes + other management to make it more natural and allow birds naturarilly repopulate the area. And restore the original balance between predators and their prey like it was working thousands years ago. In the end you are helping to forest, foresters, birds + minimize the need for widespread use of chemical insecticides.

    *There can be also another applications like introduction of new predators, but this is not my case.

    @Hazel:

    Thank you too. I'll check the reference and mybe even contact INRA. But I have to admit that shooting them with paintball gun (page. 16) sounds like more fun :)

    Unfortunately I have no experiance with predation of invasive species. My guess is that the birds may prefere local species, but if we attract more birds in the area, they may be more interested about them due to higher competition for food.
  • In reply to Noisette:

    Hazel C said:
    Box-moth caterpillars

    Is that Cydalima perspectalis Noisette? If so, what are you using against that?

  • In reply to Miroslav R.:

    Morning.

    We think that the Parus Major citations were in Ornis and BioTerra. My partner's writing to them today to check that out.

  • I can't help with that, but sounds an interesting and worthwhile bit of research.
  • Hi Miroslav
    Thank you for your nice and clear explanation, I hope your research pays dividends
  • In reply to Dave - CH:

    Dave - CH said:

    Hazel C said:
    Box-moth caterpillars

    Is that Cydalima perspectalis Noisette? If so, what are you using against that?

    Hi Dave, Yes it is & it's causing huge damage, especially in the wild. In public gardens they are using a chemical that means the area has to be closed to the public for 6 hours, not my idea of a solution.

    In our garden we cut the bush down to about quarter height & its been ok, slowly growing back, but they came back last year. On the insect forum they came up with a purée of dead adults, diluted & sprayed on the bushes, but I'm not sure whether it worked.

    Best wishes

    Hazel in the Gironde estuary, France

  • In reply to Noisette:

    Hazel C said:
    Hi Dave, Yes it is & it's causing huge damage

    Hmmm... thought so. 

    It really kicked off here around five or so years ago, having (I have it on reasonable authority) come in on infected plants at the airport in Basel around 13 years earlier.

    The damage is absolutely shocking. And it's so common that I'd never plant Box again (having just bought a house from a topiary enthusiast).

    We're now at over 800 m and it's far less prevalent. Down at 460 or so, I would spend around three days spraying between May and autumn. Faster with a 20 L satchel-type sprayer, or with a motorized one (which does a three-hour job in 10 minutes).

    Here we use a product called Delphin, made by Andermatt BioGarden. It may still be the only effective treatment available in Switzerland.

    Spray twice around 10 days apart to get the full cycle. Not toxic to humans or animals (to my knowledge); so no need to close areas off.

    Perhaps something to look into?

    Or move up to 800m+.

    Or dig up the Box and plant Yew.

    Best regards - 

    Dave 

  • To be honest I don't worry about the box in my garden, it's the thousands of plants in the wild that just won't survive. I've seen tens of thousands of these moths in flight under the floodlights of a Rugby game, it's frightening.

    Best wishes

    Hazel in the Gironde estuary, France

  • In reply to Noisette:

    Hazel C said:
    I don't worry about the box in my garden, it's the thousands of plants in the wild

    Yes, of course. You are right.

    I've seen a lot of damage in woodland. I don't know how long it takes individual plants to give up the ghost. I've seen Box come back from repeated infestations (over years) (where, for example, the people who "own" them simply don't care about them, and so don't treat them). But I suppose that eventually the plants will be so weak that they will simply die.

    I wonder why one is stopped from taking a ham sandwich or an extra 20g of butter across a border, but we can move things like this from country to country (or continent to continent) at the drop of a hat.

    I once spent an hour at the Swiss--Italien border while a border guard calculated our fine for forgetting the litre of beer that we had in the cooler. But he never talked about the plants, which we shouldn't have been allowed to import.

    Practically unlimited travel (for the relatively wealthy) and huge international flows of goods probably don't help.

    The garden as zoo, perhaps.

    Dave