I'm Robert Cameron
and I've come down to this riverbank today
to show you how to do a banded nail hunt.
What we have to do is, firstly, learn
to recognise the species we're interested in,
to tell them apart from other species and how to go looking for them.
So we'll make a start.
These snails can be found in lots of different habitats,
like hedges or woods,
but something like this, a riverbank, with some nettles and reeds,
is absolutely ideal for them.
They really like this kind of place.
But I think we'll be lucky and find something here.
So this is a good habitat to look at.
If you're lucky, snails sometimes are sitting on the vegetation
and if you peer gently...
Don't knock the vegetation too hard or they may fall off.
And we just go along having a look.
Yes, look. Under these reeds there's quite a number.
I can see both the species we're interested in straight off.
We'll have a look at them in more detail later.
But you can see how they're clustering
on the undersides of the leaves.
Of course, not all the snails will be climbing up the vegetation.
Some of them will be sitting on the ground
and it's also perfectly possible to use empty shells,
so long as they're nice and fresh.
So I'm going to have a scout around on the ground,
underneath the vegetation,
and see what I can find.
Here's one live one I've found immediately.
And here...just on the edge,
there are some dead shells.
But you can see they're quite brightly coloured
so we can score them very easily.
Indeed, you can keep the dead shells
as a collection for yourself, if you want.
The two species we're interested in
are Cepaea hortensis and Cepaea nemoralis.
I've just found a Cepaea hortensis here
and I know it's a Cepaea hortensis
because it's a shell with a white lip to the mouth.
But here is a Cepaea nemoralis,
the other species we're interested in.
You can see, very obviously,
that it's got a black lip
or very dark brown round the mouth of the shell.
That's the most reliable way of telling the two species apart.
One problem that we have
is that, of course, there are not only the adult-shelled snails
I showed you just now.
Of course, there are babies.
Because the babies don't have a lip, we can't tell which species they are.
So when you record for the snail hunt,
we want you to only look at the adults that have got a complete lip.
If you look closely, I've got two babies here
and you can see that apart from being smaller,
the shell just ends sharply.
There's no lip, either white or black, to be seen.
Of course, when you go snail hunting,
you're not only going to find the two snails we're really interested in.
There are lots of others around and some of them look quite similar.
Now I want to tell you something about the varieties
and how to score them.
The varieties are of two sorts.
Firstly, we look at the shell colour
and then we look at whether or not there are bands on the shell.
Now, as it happens, all these three shells, snails in my hand,
are unbanded.
You can see the shell is purely one colour all over.
The categories we want you to put them in is:
Is it a yellow, like this one?
Pink, like this one?
Or brown, like this one?
The other aspects of variation in these snails
that we want you to look at is their bands.
And here I have the three major varieties
that we're asking you to record.
Unbanded, which you've seen before
when I showed you all the unbanded shells.
Single-banded or mid-banded, with one band in the middle.
And many-banded, with lots of bands.
Once you've collected your snails, we want to record them.
You'll have seen the recording sheet on the website.
And I collect at least all the live snails up
and we can put them back where they came from
because they're not doing any harm to anybody
and we want to preserve the populations.
So I just scatter them back...
...where I'd found them.
So we've completed our record card.
Now we want to enter it.
So we go to the website, we look at "Enter a record,"
we complete the record sheet, following the instructions
and we send it off.
And very soon you'll get an acknowledgement back
from the MegaLab Centre telling you about your record
and about the nearest records to it.