Friday, November 27, 2009

Otter vs Mink - who's winning?

Carole and I have just got back from a week away at our little cottage tucked away in Lower End, literally on the Bedfordshire/Buckinghamshire border (our front room is in Buckinghamshire and our front door opens on to Bedfordshire!). Frustratingly, I've left the camera/computer lead there, so I'll pop back to get it tomorrow and, hopefully, post something then.

In the meantime, and following on from my last post, there is a fascinating article by Andrew & Lauren Harrington in November's BBC Wildlife magazine exploring the relationship between Otters, Polecats and Mink now that the former two mammals are, once again, on the increase in our countryside - this is certainly true of Bedfordshire.

I love the opening paragraph: 'Like Goldilocks, American Mink moved into an empty house - and ever since they've been breaking the furniture, sleeping in the beds and eating the porridge (well, Water Voles). They've done very well for themselves in Britain. But, over the past few years, the local 'bears' - Otters and Polecats - have started making a comeback. The stage is set for a kind of modern day 'war in the willows' and the battle is on. Or is it?'

Andrew and Lauren are well-placed and well-qualified to comment, working for Oxford University's Wildlife Conservation Research Unit, and having studied Mink on the River Thames at Oxford since 2003.

In recent years there has been encouraging news circulating in various circles involving naturalists and other wildlife enthusiasts, particularly those individuals who have rued the decimation of our Water Vole population. The hopeful talk has been of circumstantial evidence confirming that our returning Otters are, indeed, beginning to displace Mink. But Andrew & Lauren's research seems to suggest otherwise. Although Mink scats are not being encountered as often as in previous years alongside their riverine habitat, healthy Mink are still being trapped as frequently as ever on 'Mink rafts'.

I find the theory as to what is going on fascinating. Let me quote the relevant paragraphs:

'The Mink appeared to be occupying the same waterside real estate, in the same general pattern as before the arrival of Otters, with several non-overlapping female territories being overlapped by that of a single male. They ate a little less fish and a few more birds, but otherwise nothing much seemed to have changed. However, when walking the river by day to search for Mink dens, we came across a Mink swimming.
This was not unusual in itself (though we would have expected the nocturnal Mink to be sleeping). Mink are as adaptable in their habits as in habitat. But it became more noteworthy when our teams of volunteers went out at night wielding radio transmitters and antennae, all set to track several Mink that had been fitted with tiny radio-transmitters on collars, only to find them all sleeping, safely tucked up in their dens.
We followed our Mink intently, around the clock, and confirmed that they were now sleeping at night, but active in the middle of the day. Curious, we dug through old files to find radio-tracking data from the 1990s, before the Otters had returned, and discovered that in those days Mink behaved as expected: they were active at night (generally for only a couple of hours) and mostly slept during the day. It would seem that our Mink have changed their activity patterns to avoid the large nocturnal Otters...The strange disappearance of the Mink scats may simply mean that the Mink are less keen to advertise their presence now.'

It may be that the Mink are avoiding the nocturnal Polecat, too, and it has been noted that Mink today are on average 100-200g lighter than those caught and examined in the 1990s, which could be a result of the new challenges they're facing in the face of the return of our Otters and Polecats.

The article concludes, ' the intensely farmed landscape of southern England, where Mink are confined to narrow strips of riverside habitat, it is harder to avoid competitors, and so other strategies may be necessary for them to live side by side with their relatives. it is also possible that more subtle effects, such as decreased body weight or increased stress, may cause a decline in Mink numbers in the longer term.
This, as you can probably see, is only the beginning of the story. A field biologist's job is never done - only time will tell what will happen on our rivers over the next decade.'

Saturday, November 21, 2009

Priory Country Park - Finger Lakes

I found a few remains of old Otter spraint earlier today....David Barnes found a whole Otter!

This is one of several of David's brilliant photos that you'll find on the Priory Country Park blog (see the link on the right-hand side) following his brilliant encounter with an Otter in the Finger Lakes this morning.

Priory Country Park was one of the places that I'd considered visiting earlier - there have been Otter sightings there on and off for the last few years and I've spent many hours in the Kramer Hide on cold, frosty mornings....hoping!

The good news is that we seem to be getting more Otter sightings in Bedfordshire and, interestingly, more during the daylight hours. This has been noted elsewhere, too, and may be down to the fact that the Otters are beginning to realise that they're most likely not going to be shot, or set on by hounds!* In recent weeks, a dead Otter was picked up close to Broom Gravel Pits, a mother and cubs has been spotted on the Ouse at Kempston, and there have been other sightings on the Ouse at Great Barford, and at Stewartby Lake and Harrold Odell Country Park....and I'm determined to get my own sighting before Christmas!

* I'm hoping that someone will buy me Kruuk's book - Otters: Ecology, Behaviour and Conservation - for Christmas. I think that he talks there about experiments that have established that salt water fish are more active at night, whilst the situation is reversed for coarse fish. This is posited as one reason why our inland Otters are more nocturnal compared to the Otters in Scotland, which seems to suggest that our local Otters will continue to spend a lot of time night-fishing!

Marston Vale Country Park - Wetlands

This morning I finally got out after being all but stuck inside for several weeks….oh, how I needed it...and enjoyed it!

I spent a few hours walking around the wetlands at MVCP. There were lots of finches about: Bullfinch, Goldfinch, Chaffinch & Greenfinch, and Redwings were everywhere, stripping the Hawthorns of their berries and constantly calling to one another.

At the Wetland Hide, I was really encouraged when I heard, and then saw, a Cetti’s Warbler flitting through the Reeds on the island. The waterfowl are building up on The Pillinge. I couldn’t find a Scaup amongst the rafts of Tufted Duck, but there was a solitary female Red Crested Pochard on the west side.

I was looking around for Otter spraint and, after a muddy scramble, I was really pleased to find some on the square stone at the end of this culvert on the right-hand side.

It was not fresh, but the smell was still obvious…sweet & fishy!! It looks like this piece of stone may have been placed here specifically for this purpose.

I came across this feather underneath a Tawny Owl nesting box. I’ve seen the like before and I should know what it is….but I just can’t get my brain to stump up the answer….any ideas?
Update: Steve Blain, our Bird Recorder, is fairly confident that this is one of the wing coverts from a female Pheasant.

I’m fairly sure that this is the Brown Rollrim (Paxillus involutus), the cap margin being inrolled. It’s not one to take home and include with your salad because it has been known to kill people when eaten over a period of time!

And this is the local millinery store for the little folk who come out at night and dance around the wetlands when we’re all tucked up in bed….Fairy Inkcaps (Coprinus disseminatus)!!

Wednesday, November 18, 2009

Lower School, Ampthill

“It’s the first time that he’s sat through an assembly!”

The teacher’s words this morning regarding one of her more challenging pupils, and coming at the end of an assembly on the topic of migration, were a real encouragement. Every few months, I lead a wildlife assembly at one of the Lower Schools here in Ampthill. It started with an assembly that a group of us at the Bedfordshire Natural History Society put together, and the relationship has continued and grown. Sadly, the vast majority of our children seem to be losing touch with our local wildlife. When I held up a photo of a Swallow and asked if anyone knew what it was, the answers ranged from Blackbird to Magpie. It's the same story at the other schools I’m involved with, including the local Middle School, so it's a real privilege to be able to help at least some enthusiastic young people re-connect with their natural heritage, if in a small way.

The children range from pre-school to nine years of age, and I find it a real challenge to include all of them. I think good teachers earn every penny they make! This morning I began by telling the exciting story of Doug Holden’s discovery of the Eastern Crowned Warbler in Trow Quarry last month. We thought about just how far this bird had been blown off course from its home in Asia, and then considered the deliberate migration of a number of our birds.

We thought about how the Swallows that grace our skies in the summer are now catching insects on the wing some 6000 miles away in South Africa, and followed their journey across Europe and southwards through Africa, with many avoiding the Sahara by flying down the western coastline, or alongside the Nile.

We paused to consider how people used to believe that Swallows spent the winter hibernating alongside Frogs in the bottom of ponds, and I asked how it is we now know what really happens. “Because people on the telly tell us,” one young boy responded wisely! I talked about how, in the past, White Storks in Germany were sometimes found pierced with African arrows, and went on to discuss the importance of bird-ringing studies today.

We then thought about the House Martin, a bird that has built its delicate mud nest under the eaves of several of the homes represented in the hall. The children were amazed to learn that, out of some 3,000,000 birds ringed over the years, only one has been recovered south of the Sahara – in Nigeria, though small flocks have been observed in the mountainous regions of Zambia.

The next bird we considered was the Cuckoo. Asking the children if they knew what sound a Cuckoo makes was a masterstroke - there was a spontaneous chorus of mellifluous 'cuckoos' from all over the hall as both the youngest and the eldest children joined in! One of the younger children told us about the way in which the female Cuckoo lays its eggs in another bird’s nest, which helped me to emphasize just how amazing it is that a young Cuckoo never even sees its parents and yet, in August, migrates all the way to Africa. But it’s another mystery as to where they spend their winter because their familiar voice is silent there, and only a solitary ringed individual has been recovered – in Cameroon.

Our birds don’t only migrate to Africa, of course…and so I told the story of the Manx Shearwater that flies all the way from our coastline to the ocean waters off Brazil and Argentina.

The children were amazed as I went on to discuss a few species of insects, too, that make amazing journeys year on year. There were oohs and aahs as I showed them a photo of a Painted Lady butterfly. Millions migrated to the UK earlier this year…from the Atlas Mountains of North Africa! And only in the last few weeks has the return journey finally been proved thanks to the observant viewers of BBC's Autumnwatch. It involves several generations, but it's an amazing journey nevertheless. And the same can be said for the Monarch Butterfly whose annual cycle takes it from southern Canada to Mexico and back, though the returning insects are the ‘great-grandchildren’ of those that set off.

Until this year, the journey of the Monarch Butterfly was believed to be the longest round trip by any insect in the world – some 7000 km. But we finished the assembly as we thought about how this has been trumped in an amazing way this year with news of the migration of the Globe Skimmer dragonfly, and the work of the biologist, Charles Anderson. Charles lives in the Maldives and, after years of research, has all but confirmed the migration journey of these amazing insects between India and eastern & southern Africa, an incredible round trip of some 14,000 to 18,000 km!

Wow! Isn’t wildlife amazing!! That’s my strap-line for all of these assemblies and, judging from the round of applause and whistles, and the excited comments and “thank-you’s” of the children as they made their way out of the main hall and back to their classrooms, they thought so, too!

Tuesday, November 10, 2009

Chandos Road....inside!

I came across a Thoreau quote earlier:

'Staying in the house breeds a sort of insanity always'

I think I'm going mad....I need to get out into the countryside....

Tuesday, November 3, 2009

Chandos Road, Ampthill

This is my back garden - the wooden box is my moth trap. The following is an article published in this Autumn's edition of Muntjac, the newsletter of the Bedfordshire Natural History Society.

Trapping the fly-by-nighters
by Stephen Plummer

Have you ever thought about setting up a regular moth trap in your garden? It’s something that I’d wanted to do for years but never got around to. I’d built up a small list of moths over the years, including a Swallow-tailed moth discovered in the bathroom, and a Hummingbird Hawkmoth that had somehow wandered into the kitchen, both recorded in the autumn of 2005. But I confess that I doubted whether my very small, mostly paved rear garden here in Ampthill would actually yield much.

Then last December I came across an email that Andy Banthorpe had forwarded to the Beds Moth Group from a representative of the Garden Moth Scheme (GMS), encouraging new people to get involved. After running in the West Midlands from 2003 to 2006, the GMS now has people all over the UK recording moths in their gardens once a week between March and November, and sending the results to the GMS on a spreadsheet for analysis.

This was the nudge that I needed. I contacted one of the Scheme’s representatives and was delighted to be offered a free 15W Actinic Skinner Moth Trap and accessories, one of 10 available to be given to new members.

In March of this year I started putting the trap out every Thursday night. After a few disappointingly empty traps, I was really excited on March 19th to find my first six moths: four Common Quakers, a Small Quaker and a Clouded Drab. Lift off! From then on the species list started to grow. Some of my favourites during those early days included The Streamer, a beautiful violet-tinged specimen, and the dramatic Nut-tree Tussock.

But I guess it’s the Hawkmoth family that has the biggest ‘wow’ factor for most of us. I just didn’t think I would ever get any on my little patch. Then on May 14th, I peered into the trap to find a stunning bright Lime Hawkmoth clinging to the sides. I couldn’t believe it!

And things got even better. On May 26th I put the trap out as usual, but awoke in the early hours to the sound of heavy rain outside my window. It was 2.30 am but I reluctantly decided to get up and move the trap into the garage, getting soaked in the process. In the afternoon I brought the trap out into the fresh air to dry and was overjoyed to find a Small Elephant Hawkmoth inside. A few days later I caught my first Elephant Hawkmoth and, since then, I have also added Privet Hawkmoth and Poplar Hawkmoth to the I’d happily been very wrong in my assumptions!

By now, much to my wife Carole’s despair, I was getting hooked, and the trap was being set up several times a week! Throughout June the number of species recorded continued to rise: Figure of Eight, Bird’s Wing, Lime-speck Pug, Spectacle, Bee Moth, Brown China-mark, Common Emerald, Smoky Wainscot and other marvellously named specimens visited my tiny patch. One night towards the end of June I had over 100 moths in the trap comprising 43 species! Those that I didn’t know I photographed and put on my Blog. Our recorders, Andy and Melissa Banthorpe and David Manning, would take a look and help me ID them to species if my - admittedly poor - photos showed the relevant detail.

July was a memorable month. On the evening of July 2nd I joined Andy and Melissa who were running a few traps at Maulden Wood. It was the most incredible night and I managed to see most of the record number of over 160 species that were recorded! The highlight for me was the stunning black and white spotted Leopard Moth which fluttered to the light fairly late on. Andy and Melissa gave me permission to take it home to photograph. When I got home in the early hours, I wandered into the back garden to see what was in my own trap before turning in...only to find two Leopard Moths resting on the egg boxes!

It’s always exciting to find something rare. A neat but relatively featureless moth in my trap that same night turned out to be a Fen Wainscot, the 15th Bedfordshire record, and a small micro-moth that turned up on August 17th was identified by David from my Blog as Aroga velocella, only the 3rd Bedfordshire record. I reckon this one must have come from Cooper’s Hill where it was recorded in 1997.

So far my little patch has recorded 173 separate species: a real revelation to me. Let me encourage you to get yourself a trap and have a go if, like me, you’ve been putting it off for some time. Maybe you’d like to become a part of the Garden Moth Scheme. Our Recorders are always really helpful in giving advice and helping with identification, and your records are always appreciated. There is a Beds Moth Group on the Internet where you can learn how other people are getting on, and there are lots of other helpful websites to inspire you.

You just never know what will be there when you peer into the trap in the morning. But I warn you now: it’s addictive!