The resilience of water voles

Two weeks ago, Radley Brook had burst it's banks and the Thames path was flooded and impassable
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Now the water level has subsided and the weather has been so dry that the path is now passable again:
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So it is an opportunity to try and find if any water voles are still there and have survived the recent flooding.  In the bank, it looks like there might be a burrow:
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And in-between the sedge, a collection of small cut grass stems, a definite sign of water vole feeding.
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It seems, despite the weather, the water voles of Radley Brook are still resilient - for the time being -  to the  many hardships  that water voles suffer.

River birds

Last year, a pair of mute swans tried to set up a nest along the river (http://viewsoftheock.blogspot.com/2011/04/swans.html), but unfortunately did not successfully breed .  This year, a swan has arrived, but it is on it's own.

Adult swans form partnerships for life and divorce is very rare, so either this is a new swan or last years pair have separated, possibly due to the unsuccessful breeding. 

What ever the reason it looks a somewhat sad and lonely sight as it swims solitary up and down the river.

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Grey herons are occasional visitors to the river and they can be seen stood silently by the river as they look for their prey, usually small fish and amphibians, but they will also take river birds like moorhens and small mammals - including water voles 
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A somewhat more unusual sight is a parrot, squawking at the top of one of the tallest trees by the river (seen Sunday 26th February):

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Of course parrots are not native to the UK, but ring necked parakeet's released in the 1980's and 90's have become so numerous in the south of England - they can be seen in Hyde Park in London and Windsor Great Park - they have become a nuisance 

According to the Oxfordshire Bird Blog a ring necked parakeet was seen at the Drayton Road Allotments the next day.

With the grey head and yellow beak, it does not look like a parakeet - which have green body, head and a read beak (http://www.rspb.org.uk/wildlife/birdguide/name/r/ringneckedparakeet/)  , so this is may well be a recent escapee.

If it is, can it survive? The parakeets have demonstrated it is possible for exotic birds to flourish in the UK, but there is a lack of fruit on the Ock (the fieldfares and redwings have eaten it), so it will have to find a new place to squawk, and as it wasn't there last weekend, maybe it has...

Not so good on Radley Brook

Over the past few years, this blog has focused on the trials and tribulations of two water vole colonies and whilst things are currently looking good for those one River Ock (), life is a lot harder for those on Radley Brook.
Running between the Barton Fields nature reserve and the River Thames, it is more of a ditch with stagnant water than an actual brook, but during summer, much fun can be had feeding the water voles an apple core or two.
However, it's proximity to the Thames can cause problems - the river is corridor for mink and this is where several have been seen in recent years 
And whilst there are almost certainly in otters in the river, the river is so wide that they are unlikely to offer any protection to the water voles.
Although at the moment, there are other problems for any water voles, the heavy rain on Sunday has meant the river has burst it's banks and flowed into the brook, which is now very high:
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With such a rapid increase in water level, any water voles trying to define their territory or make and renovate  their burrows could have been drowned.
And not only is the brook very high, but the Thames Path which runs alongside the brook is underwater and impassable
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Water vole colonies are fragile, and even though things look very precarious, experience says - when it comes to water voles - never to give up hope:

Bumper year for water voles?

There is plenty of evidence of water vole activity along the river at the moment, the are many freshly dug burrows in the river bank (probably old burrows being renovated).
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Some of the burrows have small cut grass stems in front of them - evidence of water vole feeding.
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The main give away of increased activity are obvious latrines, water voles define their territory by using their droppings and are most evident during the breeding season:
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Of course, the most obvious sign of water vole activity is actually seeing one and this one is making up for the lack of edible river fauna by eating the bark and lichen from one of the overhanging willow trees.
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Even though spring has not yet started, there does seem to be plenty of water vole activity already, perhaps there are several reasons....


The main contributing factor to the 90% decline in the UK water vole population since the 1950's is the release of american mink from fur farms (now banned in the UK) and mink  have been previously seen by the nearby river Thames.  
Although mink and otters can co-exist (the mink become diurnal - active during daylight) last years breeding female otter would almost certainly not tolerated a such a predator close to her cubs and would either kill or chase off a mink - to the benefit of the water voles. 


Water voles don't hibernate, so have to forage during winter - feeding off roots, tubers and as above bark and lichen off the overhanging willow trees.  However, the mild winter (with the exception of one or two weeks) has meant the voles would not have perished through the cold and would have more opportunity to feed.


Another common cause of mortality for water voles is drowning (perhaps surprising for an animal which choses to live by rivers), they can often be trapped in their burrows when water levels rise quickly.  Something which often occurs on the Ock.  So whilst the potential draught in the south of England could cause problems for other wildlife - especially amphibians (http://www.bbc.co.uk/nature/17130206)  - it could benefit the water voles on the Ock.


As a result of these, could 2012 will be a bumber year for water voles on the Ock?

Welford Park

In what now seems like an annual pilgrimage, in early spring we head down the A34 to Newbury to Welford Park.
The house, built on the grounds of an old monastery, maintained by the monks of Abingdon before dissolution, is an impressive building:
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And so is the church, one of only two round spired churches in Berkshire:
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But what people flock here in their thousands to see is the snowdrops, unlike  Waterperry gardens, what it lacks in varieties (most of the snowdrops are galanthus nivalis - the most common in England), in makes up in quantity.  The drive leading up to the house contains several thousand:
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But it is a the beech woods which is by far the most impressive, containing several million snowdrops.  It is probable these were introduced by the monks who returned from Europe who used them to decorate the monastery and use it for medical treatments.
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Although the monastery is long gone, the legacy of the monks lives on in what must be one of Berkshires most impressive natural sights.
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It is not just the several millions of snowdrops, the monks legacy also lives on in modern medical research, as snowdrops are being used into a possible treatment for Alzheimers: http://www.sciencedaily.com/releases/2009/12/091220175319.htm

Yet more Snowdrops

Today was part of Waterperry Gardens snowdrop weekend, an opportunity to see some of  the many different varieties and to learn more about snowdrops and the gardens on one of several guided walks (there is another snowdrop weekend next week).
This variety is known as 'curly' and is a natural hybrid, only recently discovered in the 1960's.  It is one of the varieties (along with Sam Arnott) and has a strong honey smell.

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This one, with the green tips on the tepals (outer petals) is a Galanthus nivalis 'Viridapice' and is another natural hybrid, discovered in Holland in the 1920's and subsequently introduced into the UK:
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Most snowdrops have single flowers, but some varieties have double flowers, like this Galanthus nivalis 'flore pleno'.  
Double flowered snowdrops are not capable of producing seeds, however, when they are cross pollenated (either naturally by insects or by people) with single flowered snowdrops the resulting seed will produce a double flower.
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Snowdrops are not native to the UK, having been introduced initially in the roman times and now with an ever increasing number of breeders and collectors (known as Galanthophiles) the popularity and number of species is likely to increase.  Especially with a record price of £725 recently being paid for a single bulb: http://www.dailymail.co.uk/news/article-2102136/Green-Tear-snowdrop-looks-glum-rival-Scottish-Elizabeth-Harrison-expensive-bulb-sold.html
But  the ever increasing popularity of snowdrops is having unexpected consequences in their native countries.  
Over harvesting in countries like Georgia could result in many species becoming extinct in the wild.  A research project between Kew Gardens and Microsoft Ecology is looking to demonstrate how a sustainable trade in snowdrops can benefit the local population whilst maintaing sufficient populations in the wild: http://www.kew.org/news/sustainable-snowdrop-trade.htm

Spring in the Garden?

The snow has now melted and thanks to a warm sun the temperature has risen to 10 degrees, as a result, some of the plants in the garden have started to flower, giving the garden an almost spring like feel.
One of the earliest was the winter aconite, an none native member of the buttercup family which can found in many gardens and woodlands throughout the UK.

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The cyclamen has also been in bloom for a while, it is the first time it has flowered and apparently the flowers can last for several months.

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The rosemary bush has been producing small flowers for most the year and is one of the most popular with the bees when they emerge from hibernation.

The flowers are quite small, but up close they have the elegance of an orchid.

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Several varieties of crocus are also in bloom, including this purple crocus:

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Most of the snowdrops are now in bloom, including this non native hybrid - Galanthus Sam Arnot' - purchased from Waterperry Gardens. 

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The behaviour of the birds has also changed, the blackbirds seem to have paired up and are chasing off other garden birds and the solitary dunnock seems to have acquired a partner and can be seen checking possible nesting sites - when they are not being chased off by the blackbirds.

Winter water voles

The temperature on early Saturday morning dropped to about -9 degrees centigrade (16 degrees fahrenheit) and never went above freezing throughout the day and fridays snow was still on the ground
Even so, the water voles were still about, this one nibbling on the dead sticks sticking out of the snow
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Possibly the same water vole seen last week, but the population is more than just this one, as this another appeared ten minutes later on the opposite bank.
It's good to see, that despite the weather, this most endearing of animals is still surviving along the river - especially when all they have to eat is dead sticks.
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More snow and footprints

Another snowfall provided an opportunity for a scenic walk along the Ock Valley Walk on Friday:
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Like the previous week's snowfall it presented an opportunity to look for animal footprints to try and work out what had been around in the early hours and the morning
The most common are domestic dogs, these are usually larger than the fox prints, but the most obvious evidence that they are dogs not foxes is there are human footprints next to them:
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The thrushes and blackbirds also leave obvious footprints:
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These hoofed mammal (ungulate) prints almost certainly belong to one of the increasing number of muntjac deer who can be seen along the river Ock.
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