Concerned

In spite of the photos above, I've been concerned this last week that there has been a drop in water vole numbers at one particular site, and in fact I've had three days where I've seen nothing at all. I haven't spotted any sign of mink but there is quite a lot of stoat scat about, and I've had a couple of trail cam clips. So as soon as this rain stops, I'll go back out and have a really good look to try and work out what's going on. Stoats are native predators, therefore they shouldn't be a problem, but I suppose if there's been a big enough explosion in the population this year then that might have reduced water vole numbers severely.

The Mustelid Contingent

Stoat

Water vole

Adult rat - the relative sizes

It was a surprise to pick up this stoat on the trail cam. This makes the fourth mustelid I've seen in the field (if you count finding otter spraint as a 'sighting'). I've also seen weasels and a polecat here. All these predators will eat water voles, but because they're native and in the balance, vole numbers stay buoyant. The worry is if mink invade, because they are non-native carnivores and can wipe out whole colonies of water voles in a matter of weeks.

Bumper Year for Water Voles?

http://news.bbc.co.uk/1/hi/sci/tech/8346632.stm

.

Possibly a slightly misleading headline, as more recorded sightings doesn't necessarily mean more water voles, but it's still encouraging. The linear nature of canals actually can work against water voles, as mink also like defined linear routes; some of the best habitats for water voles I've come across are ponds and ditches away from the bigger water courses.

Mustelid Action at Quoisley

Old otter spriant

Not sure what this is: it's definitely mustelid, but had no detectable smell so could feasibly be mink.
.

Here's a busy place! After the comments on my last post, I went to take another look at Quoisley. I don't bother with this area much because I suspect there are now mink around that section of the canal and therefore no water voles: Malcolm Monie and I surveyed several ditches there last summer and drew a blank.
.

However, the bridge looks as though it's a very ottery spot, judging by the amount of spraint on the kerb under there. That's probably good news for water voles, in that the theory is otters drive away mink. While otters do take the odd vole, they don't go through a whole colony and wipe it out the way a female mink does.

Summary of 2009

The vole-watching season's pretty much over, so this blog will be doing what the water voles do, which is to go into semi-hibernation till the spring (not true hibernation, but a kind of torpor with only occasional appearances above ground!).

.

So has it been a good year for water voles in and around Whitchurch? Well, there've been gains and losses, as some colonies began well and then seemed to fall away, and others started hesitantly and became very strong. The most active have been in the fields near me, the ditches near Grocontinental which have afforded me lots of sightings and photographs. White Lion Meadow's been quiet, but perhaps not as quiet as sightings would suggest, in that I've spent a lot less time watching there because there wasn't so much obvious activity - a vicious and unscientific circle. I'm still not sure whether the sightings across the car park at Lidl were field/bank vole.

.

Edward German Drive has been steady: no actual sightings, but a lot of clear field signs. The back of Wayland Road is hard to access, but there were certainly water voles there mid-summer.

.

Moving further up, the section by the railway bridge near Homebase suffered some kind of crash: last year there was a very strong colony there, and there were plenty of field signs in spring 2009. But when I surveyed late summer, there was nothing at all round the bridge, only at the end near the field. I have no explanation for that, but it goes to show how what looks like a completely established group can easily be wiped out. However, they do beed quickly, and colonies naturally shift and expand and contract, so as long as there are voles on reither side, that section should be repopulated again as the habitat's excellent.

.

Albert and I both found lots of vole activity at Black Park Road, but I couldn't see anything at Yockings Gate. There was some vicious dredging there, so I think it'll need anopther year before the banks are suitable again. And I haven't followed the Staggs Brook further up as it's private land. The golf course now seems to have lost all its water voles (and there were so many a few years back! I suspect mink as we've had reports from round there) but there've been vole sightings in ditches close by.

.

On the other side of town the various colonies at the Country Park have been consistent, and moving out of Whitchurch, we've continued to see field signs at Steel Heath, the Prees Branch Canal between Waterloo and Whixall Marina, and in Whixall generally. I haven't spent much time oneither Brown Moss or Whixall Moss this year, so I don't know how the voles are doing there.

.

Anyway, all we can do is hope enough make it through the winter to get cracking next year. I'll be out with my camera the first warm day in February!

When you draw a blank

Field vole droppings - water voles' are twice the size

.

Sometimes an area looks brilliant for water voles, but a survey throws up hardly anything and it's hard not to feel a little disheartened. Emma Broad, biodiversity officer for the Wrexham area, organized a survey day round Pulford, and pretty much all my group found was field vole latrines and feeding. Rob Strachan's group discovered one or two water vole droppings, but also a mink den, which probably explains why such good habitat's going unused. At least remedial action can be taken now, so in a sense the survey was a success.

.

Some nice views of a pipistrelle (?) round my back door last night. Too fast for a photo, though!

Activity at the Prees Branch Canal

I had a report of a mink-like animal a week and a half ago in the fields by the Prees Branch nature reserve. I checked at once and found nothing. But today I found this otter spraint (top photo) on the tow path. The distinguishing feature of otter poo is that it smells fishy/not unpleasantly scented/of jasmine tea. It's a really distinctive odour.

.

Otters are a mixed blessing for water voles. They do predate on voles, but on the other hand, they're native and so their impact balances out (a mink will go through a colony of water voles like a blow-torch through butter). More importantly, otters drive mink out, and will kill them. I was sent a photo just this week of a mink that had probably been dispatched by an otter, but I won't post it here as it's pretty gruesome.

.

Hearteningly, there was a lot of water vole feeding (photos 2-5) right along the whole length of the canal, and I was interested to see an example of a water vole leaving droppings on top of food. I knew field voles did this, but I've never seen it in water voles.

Mink: very bad news for water voles

Went for a walk down the Prees Branch Canal today, and it looks as though there's at least one mink in the area. I found what I'm pretty sure is mink scat, and then there were bones on the second raft.
.
My fears were confirmed when I met the lady who lives in the cottage at Waterloo and she said her fish pond had been raided. So I'm waiting to hear from SW about what to do.
.
There was evidence of water vole feeding and a fresh latrine (the two pics below) but for how long can this population survive if there are mink about?