Wednesday, 23 September 2009

Data entry and preliminary stats

Over the last three weeks or so I've been working pretty hard with my data. All the data on bird registrations have been entered in my database and I've been analysing them a bit. It's pretty crude still because the only habitat data I've entered so far are overall habitat types. This is a gross over-simplification, because in Cyprus we still have this wonderful landscape where there will be lots of different crop types in a small area.

For example, cereal fields often have olive and carob trees growing in or near them, vineyards are often bordered by almond tree-lines, and there are field margins with natural vegetation. This kind of habitat diversity is widely accepted to be fantastic in supporting high biodiversity, including farmland birds. My overall aim is to figure out where on the island these different habitat characteristics are most valuable, and for which birds, so that they can be protected as agricultural practices change.

At the moment, I've done some ordination analyses of my data, which basically compare the different bird communities across all the sites I sampled. Even with my crude habitat classification, I can already tell you that the bird communities do change across habitat types. Forests, in particular, stand out. This is important, because, not only are the birds in forests different, there aren't that many species that are found there. So farmland is really very important for most  species of conservation concern.

Cereal-dominated habitats have the fewest species. Although cereal is also quite distinct, on the opposite side of the spectrum to forests, there is a huge variety in the bird assemblages that are found in cereal fields. Vineyards have the most species, and then it's citrus groves. The bird communities in these types of agriculture, along with olive, carob and almond groves, and semi-natural scrub habitat, aren't actually that distinct though.

This is where I will be going into more detail next. I want to tease out the differences between scrub, vines, groves and cereal. But to do that I first have to get back to data entry.

It's quite boring entering data. But I suppose it's calming in a sense. You need to concentrate enough to get the right information in the right place, but that's about the only thinking that you're doing! After a few days of entering data, statistical analysis is a welcome change. And it's really satisfying to see the data I collected during months of fieldwork actually show some results that will eventually be publishable.

There's still some way to go, but hopefully by the time I leave for my winter field-season.

No comments:

Post a Comment