Bucket list ...

Eurasian Otter (Lutra lutra)

It’s taken me a very long time but I’ve finally managed to see and get a reasonable photograph of an Otter in the wild in the UK. The above male was recently spotted hunting for flatfish and crabs in a sea loch located on North Uist in the Outer Hebrides. As luck would have it, as the prevailing weather conditions really weren't very good, he decided to come out of the water and on to a small grassy bank to pause for a few moments before returning back to his watery domain.

All I can say is, "well happy" …

Through the Looking-Glass …

Brown Hare (Lepus europaeus)

Although found in many areas across the southeast, L. europaeus has become much more intermittently distributed during the last century; no more so than in my home county of Sussex. Reasons for the decline are varied but are believed to be connected to a range of factors including agricultural intensification, predation, disease, and both legal and illegal human persecution. It is due to this decline in distribution and numbers that L. europaeus was made a UK BAP priority species for conservation in 1995. Despite its decline, L. europaeus is the only game species in Britain, which does not have a shooting close season.

Although mating can take place almost all year round, with February to September forming the principal breeding season, the familiar boxing and chasing is most easily observed during March and April. Most boxing is typically a doe, the female, fighting off the unwanted sexual advances of a buck, the male, although male to male fighting is also recorded. When a doe is ready to accept a buck, following a period of chasing and a variety of gymnastic like movements, she presents herself and allows the buck to advance and briefly mate with her.

I can't help thinking he's watching me ...

References:

Bjärvall, A. and Ullström, S. (1986). Brown Hare. The Mammals of Britain and Europe. Beckenham, Kent: Croom Helm Ltd, pp. 60-62.

Corbet, G.B. and Harris, S. (1991, third edition). Brown Hare. The Handbook of British Mammals. Oxford: Blackwell Scientific Publications, pp. 154-161.

On your marks, get set …

Brown Hare (Lepus europaeus)

The taxonomic Order Lagomorpha comprises the hares, rabbits and pikas. The Brown Hare (L. europaeus) is the largest of the British lagomorphs. Since there is no evidence of their presence in Britain before Roman times, it was probably introduced by man. They are widespread on low ground throughout England and Wales. In Scotland, L. europaeus is found on farmland and rough grazing to the far north of the mainland, but is absent from parts of the North West. L. europaeus is replaced by the Mountain Hare, L. timidus, in upland areas of Scotland and central England.

Brown hares generally live in exposed habitats, and they rely on their acute senses and running at speeds of up to 70kph (45mph) to evade predation. Hares do not use burrows, but make a small depression in the ground, known as a form, amongst long grass. They spend most of the day on or near the form, typically moving out to feed in the open at night. Tender grass shoots, including cereal crops, are their main foods. Though generally solitary, hares sometimes band into loose groups when feeding.

Breeding takes place between February and September and a female can rear three or four litters a year, each of two to four young. The young, known as leverets, are born fully furred with their eyes open and are left by the female in forms a few metres from their birthplace. Once a day for the first four weeks of their lives, the leverets gather at sunset to be fed by the female, but otherwise they receive no parental care. This avoids attracting predators to the young at a stage when they are most vulnerable. Foxes are important predators of young hares and where foxes are common there are likely to be very few hares. Adults typically live to 3 or 4 years.

Numbers of hares have declined substantially since the beginning of this century, though they are still locally common animals in many parts of the country. The main reason for this decline seems to be a change in the way modern agriculture is managed. Today's farms are often intensive and specialised, either growing crops like wheat and oilseed rape, or raising livestock for meat and dairy produce. A hundred years ago most farms were varied enterprises. Mixed farms have a patchwork quilt of fields, which provide year-round grazing for hares as well as long crops for them to hide in. Modern cereal farms provide little or no food for hares in late summer and autumn, and livestock farms have few crops for them to shelter. Modern farm machinery and pesticides also kill many hares.

References:

Bjärvall, A. and Ullström, S., 1986. The Mammals of Britain and Europe. Beckenham, Kent: Croom Helm Ltd., pp. 60-62.

Corbet, G. B. and Harris, S., (eds.) 1991. The Handbook of British Mammals (3rd Edition). Oxford: Blackwell Scientific Publications, pp. 154-161.

The Mammal Society (2014). Species fact sheet: Brown Hare (Lepus europaeus). Downloaded from www.mammal.org.uk on 1st May 2014.

Gene flow ...

Arundel Wetlands

The beautiful water vole, Arvicola amphibius, was once a common site along the banks of the Arun Valley waterways. However, the modification of landscapes for agriculture and urbanisation, and the colonisation of the American mink, Neovison vison, led to their dramatic decline both locally and nationwide. In Sussex alone, we have sadly lost over 90% of our historic populations.

The Arun Valley water vole project is studying the gene flow within and between water vole populations, and investigating the effect of different habitats and landscapes in Sussex. The research is being undertaken during 2012 and 2013 and involves both field and laboratory techniques.

With the help of volunteers, numerous ditches were surveyed over a three month period, and evidence of breeding water voles was found on 13% of the waterways surveyed. This was an encouraging sign but, for the most part, only a few latrines were recorded. However, it was on an agricultural drainage ditch at Houghton Bridge, near Amberley, that signs of recolonisation were evident. Large concentrations of water vole latrines, feeding stations and burrows were present, indicating a potentially viable breeding population. This was great news as it suggested that water voles were recolonising northwards up the valley.

This raised several questions:

Had this newly found population come from Arundel Wildfowl & Wetlands Trust (AWWT), which is a reintroduction site located approximately 6.5km downstream?

Was the population too isolated and unable to rely on new individuals that would provide demographic and genetic rescue?

Can farmland ditches, not managed for water voles, hold viable populations?

Over the last two years Rowenna Baker has set out to answer these questions by studying the genetic structure and demographics of water voles at Houghton Bridge and AWWT through live trapping individuals each year, PIT (passive integrated transponder) Tagging, and by taking hair samples to obtain DNA for genetic mapping. Encouragingly, the abundance of water voles at Houghton Bridge is comparable to other natural colonies occurring along similar habitats nationwide, with estimates ranging from 20 to 50 individuals along 1km of bank. The population is small in comparison to  AWWT (135 individuals in 2010), where they are not affected by the external pressures of grazing and predation that commonly constrain habitat availability and density in unprotected sites. Both populations remain genetically diverse, however dispersal between populations is low, which is unsurprising as the average dispersal of water voles is 1-2km.

Despite the importance of genetic fitness, little is currently known about the genetic structure of water vole populations and what factors facilitate or impede gene flow within and between populations. Other studies have found that increasing distance between populations, land use and habitat design can all influence gene flow in animal populations.

The Arundel population is clearly a vital source for the recolonisation of water voles within the valley, however it is crucial that landscape connectivity is improved to aid dispersal between newly established populations. With additional colonies being found as far north as Pulborough Brooks, Rowenna now uses remote hair tubes to obtain genetic samples from all occupied sites in order to investigate gene flow and factors that facilitate and impede dispersal. This information will help to guide management to strengthen isolated populations by creating habitat networks that will hopefully promote water vole dispersal and recolonisation.

An important project regarding an excellent flagship species and one which I was privileged to witness first hand.

My thanks to Rowenna ...

First one to blink ...

Roe Deer

The roe deer, Capreolus capreolus, is primarily an animal of open mixed, coniferous or purely deciduous woodland but is also capable of adjusting to a wide range of other environments. It has also penetrated many towns, making use of gardens, parks and other open spaces where suitable food and cover exist. It may often be seen well out into open farmland, particularly when occurring at high densities.

Roe deer are indigenous to Britain, having been present since at least the Mesolithic period (6,000 to 10,000 bp). The clearance of forests and over-exploitation by hunting led to roe deer becoming extremely scarce in the medieval period. By 1700 it was considered extinct in southern and central England and all of Wales, surviving only in remnant woodlands in parts of the central and northwest Highlands of Scotland. A number of reintroductions during the Victorian era, and their subsequent natural spread aided by an increase in woodland and forest planting in the 20th century, has meant that roe deer have become widespread and abundant today.

A roe doe listens and watches ...

After dark ...

Bats in the attic?

Despite the loss of over 90% of our bats in the past 50 years or so, 18 species of these increasingly uncommon nocturnal creatures can sometimes still be found in southern Britain. Although legally protected, most species of these tiny intelligent mammals sadly continue to decline in numbers, mainly due to loss of habitat and changes in farming practice. All British bats eat only insects, populations of which have also reduced massively in the past fifty years or so. In Britain, a female bat has only a single baby (pup) each year, and often cannot give birth in poor summers; such as those we have experienced recently. Such slow reproduction makes it extremely difficult to reverse the decline of these beautiful and delicate mammals.

Most of our bats like to roost in trees, but a few species have adapted to take advantage of the opportunities offered by buildings at certain times of year. For example, a warmer environment can help a bat rear its pup during the summer. The pup is reared on its mother’s milk until it can fly, which may be as soon as three weeks after it is born. By autumn, the house dwelling maternity colony will typically be dispersing to mate and then to hibernate, perhaps in trees or underground sites.

Although they occasionally do, their presence needn’t worry householders – in fact most people remain quite unaware of their secretive little lodgers. Bats by their very nature are clean, gentle little animals, which spend much of their time grooming. They don’t build nests, so won’t bring any messy materials into the house and, perhaps most important of all, they don’t gnaw and chew at things, so won’t cause damage to electrical wiring and cables.

Bat droppings are sometimes found beneath roosts, but these are quite harmless and are not known to harbour disease. Droppings are sometimes seen on outside walls and windowsills near to roost entrances, but can also accumulate in lofts. If swept up after the bats have left, they make excellent fertiliser for houseplants. Bat and mouse droppings look very similar, but there is an easy way to tell them apart. Bat droppings consist only of the dried out fragments of insects and, if rolled between your finger and thumb, they will crumble away into dust; they also have a slight ‘sparkle’ about them. On the other hand, mouse droppings are solid, generally dull in appearance and remain in one piece.

Which bats live in houses?

The two very rare horseshoe bat species, the greater horseshoe (Rhinolophus ferrumequinum), and the lesser horseshoe (Rhinolophus hipposideros), like to roost in buildings, but are no longer regularly found in the south east of England. None have been recorded in Kent and Surrey for many years, and a mere handful remain in West Sussex. Usually found are our most common bats, the common pipistrelle (Pipistrellus pipistrellus) and the soprano pipistrelle (P. pygmaeus), which as crevice dwelling species, like to tuck themselves into gaps around the outside of properties rather than enter the loft space. They tend to do this mostly in the summer months when groups of females will cluster together in a warm spot to rear their young hidden beneath barge boards, hanging tiles and so on. In winter, odd individuals are sometimes found hibernating in similar gaps, but this time in the coldest rather than warmest places on the house. Perhaps surprisingly, pipistrelles seem very fond of modern houses, especially where small gaps and splits have opened for them into which they can squeeze. Though little more than an inch (2.5cms) in length, a pipistrelle can eat up to 3000 midges in a single night, and needs to do so to fuel its energetic lifestyle.

Another house specialist is the brown long-eared bat (Plecotus auritus), small groups of which will congregate in the lofts of (usually) older houses for a few months in the summer, again whilst the young are being reared. Larger than the tiny pipistrelle, it has huge ears, almost as long as its body, which it uses to listen by means of echolocation for its insect prey. The ears are tucked safely beneath the wings for protection whilst the animal is at rest. An individual bat will occasionally remain in a cold part of the loft to hibernate. A much rarer house dweller, and one of our largest bats, is the serotine (Eptesicus serotinus). Several times the size of a pipistrelle, it is still very small - a little over three inches (8cms) in length, although its wings may span over a foot (>30cms) in flight. These favour the lofts and attics of houses built at least 100 years ago where a few will occasionally roost during the maternity period. They have also been known to hibernate, usually singly, in roofs or cavity walls. Serotine bats are particularly fond of flying beetles such as cockchafers, which they catch on the wing. Other species of bat are much rarer in England and are very seldom found in houses.

Advice on your bats

If you have any concerns about bats in your property, do call the Bat Helpline on 0845 1300 228 – they can provide lots of advice and literature on bats, and even arrange free advice where building repairs, timber treatment and so on are necessary in or near a roost. Their web site www.bats.org.uk provides a wealth of information about bats, and many leaflets can be freely downloaded. They also run a rescue service – so if you find a grounded bat, give them a call and someone will be able to help.

Bats and rabies

The European strain of rabies found in bats is extremely rare in Britain. Only ten cases have been identified since 1986, all of them in a single species that does not roost in houses. There is no need to worry about rabies if you do not handle bats – the disease is only passed via a bite or scratch, or from an animal’s saliva coming into contact with eyes, mouth, nose or an open wound. As a precaution, bats should not be handled. If it is necessary to do so in the case of a grounded or injured bat, gloves should be worn - and don’t forget to call the Bat Helpline, as detailed above, for advice or support from a local bat worker.

My thanks to Martyn Phillis (Surrey Bat Group) for his assistance with this article. All images copyright Martyn Phillis.

Arvicola amphibius ...

European Water Vole

"Believe me, my young friend, there is nothing - absolutely nothing - half so much worth doing as simply messing about in boats”

Rat, Chapter 1 ...

Kenneth Grahame, The Wind in the Willows

The European water vole, Arvicola amphibius, Linnaeus (1758), formerly A. terrestris, is widespread across Europe where it lives in the well-vegetated banks of slow moving streams, rivers, dykes and other waterways. It is found throughout Britain where it is generally confined to low ground. It is absent from Ireland. The extensive waterside burrows of these strong swimmers have many levels that help to prevent flooding, as well as chambers for nesting and food storage. Burrow systems are typically located in the steepest parts of the bank and usually have underwater entrances to give the animals a secure escape route if danger threatens.

A. amphibius has a diet of grasses and waterside vegetation, though other broadleaved plants are also eaten. Where blades are bitten off the imprint of the two large incisors is both prominent and diagnostic. It is not uncommon to see "lawns" of closely manicured grass, occasionally with piles of chopped food, around burrow entrances. A. amphibius tend to be more active during the day than at night. The males range along about 130 metres of water bank, while females restrict their range to about 70 metres. Ranges of both sexes and all age classes are reduced during the winter period. They deposit their distinctive black, shiny faeces in latrines, which occur throughout and at the edges of their range and wherever they leave or enter the water. Three or four litters a year are typical. In mild springs the first of these can be born as early as March or April; though adverse conditions will delay breeding until May or even June. There are about five young in an average litter, which are born below ground in a nest lined with finely shredded grasses and reeds. Although blind and hairless at birth, the young develop quickly and are weaned at 14 days. On average, water voles only live about five months in the wild.

Their most important predators are mink and stoats; though other predators are known to take them. They have sadly experienced one of the most severe declines of any wild mammal in Britain during the 20th century. Changes in farming practices during the 1940s and 1950s caused the loss and degradation of suitable habitats but the most rapid period of decline was undoubtedly during the 1980s and 1990s when the American mink (Neovison vison) spread rapidly across the country having been released from fur farms. Between 1990 and 1998, the population dropped by a staggering 90%.

Arvicola amphibius is an excellent flagship species and one which we should endevour to protect. Their presence reflects a healthy aquatic environment and associated waterside communities.

Revisited ...

Isles of Scilly, 25 August to 1 September 2012 - Part 1

Located just 28 miles (45 km) off the southwestern tip of the Cornish peninsula the Isles of Scilly form an archipelago of five inhabited islands and numerous other rocky islets (around 140 in total). An opportunity to take my son and elderly parents on holiday found me venturing back to this beautiful location after an absence of six years. After a five and a half hour car journey and a twenty minute helicopter crossing we finally arrived at St Mary's and the Star Castle Hotel; our base for the week ahead. Our arrival was welcomed by clear blue sky, sunshine and strong westerly winds. I had visions of a rare American vagrant (well you've got to be optimistic) ...

Bags unpacked, a short, late afternoon walk around a small section of The Garrison revealed Large White, Small White, Speckled Wood, Holly Blue, Meadow Brown (ssp. cassiteridum) and a beautiful Red Admiral sheltering from the strong wind.

Sunday

A hearty breakfast (with all the extras) was followed by a circular walk around the outer wall of The Garrison. This produced good numbers of Common Blue, including numerous strongly marked blue females. Scrub ivy grows over much of the more sheltered areas of The Garrison and Holly Blue were seen in greater numbers than I've observed for some time on the mainland. At 1.30pm (after a light lunch) we headed to the high seas for an exhilarating afternoon on board a 225HP RIB in search of the Atlantic Grey Seal (Halichoerus grypus). After a detailed search and with the tide dropping in our favour, several small groups were found around the Eastern Isles.

Three of numerous (many out of focus) shots below ...

To be continued ...