Edge habitat

[Chris Raper]

On 20 Jun 1999 05:19:19 -0700, Bobat23rd at aol.com wrote:

>Dear Andrew,

Hi Bob (& Andrew)

Sorry to 'chime in' to your conversation - but by making the post to
the group as a whole I assume you were hoping to widen the debate.

>I am in a land trust in Maine and we have recently purchased 270 acres. 
>One of the board 
>members is trying to get us to agree to cutting back to fields to the 
>original maps of 1938 when the land was used as a dairy farm. Dairy is now 
>obsolete in our area and we feel that this is  destroying habitat (it  has 
>since started to come back to woods) Can you explain the upside and the 
>downside of creating edge habitat? I need to know how to argue this point 
>technically. Or where can I find this info.

Well, by 'edge habitat' I am assuming you mean 'creating a graded wood
edge' - i.e. softening the edge of a wood/field boudary by allowing a
belt of low-growing scrub to develop?

I'm afraid I don't have any sources of information - I have just
picked this stuff up as I went along. But I have always understood
that the argument _for_ this kind of habitat is basically that it
increases the number of habitats in the area - and thereby improves
the species diversity - especially for inverebrates.

On the reserve I manage (mixed grassland and woodland) we have tried,
wherever possible' to make all edges very rough with vegetation at
different heights. We also promote a wide range of plant species to
provide a good selection of food plants, nectar sources and living
areas for invertebrates. The general aim is to provide as many
different micro-habitats as you can in the area allowed. Remember,
most invertebrates often only need tiny habitats to fulfill their
requirements for life - but these habitats may be very specific. A
classic case is hoverflies whose larvae live in wet, rotting wood in
the holes in trees. Not only do different species of fly favour
different species of tree but they also need holes at different
heights and often need other suitable habitats (for couting/feeding)
in close proximity! 

I don't really see a problem with people being on the land and even
farming a portion of it. It is easy to forget that most of the
habitats we treasure today - dry grassland, hay meadows, hedges,
coppiced woodland etc are all man-made. If we just left the
countryside it would revert back to wildwood in a remarkably short
period of time and, although wildwood is very valuable, it wouldn't be
very good for all those species that have adapted to living in the
other habitats. :-)

Hope that helps
Chris R.