Ray Collier Country Diary- Brown Rats

Brown Rats - 30th December 2008

Brown rats can be readily identified as adults by their eleven inch long head and body and the nine inch tail. The colour of the coat varies from brown to black but is generally brown or grey streaked above and paler grey below. Sometimes there is a white patch on the chest and light coloured forelegs. The tail is thick, dark above and pale beneath and is often scaly and the ears are short with some hairs. Tracks of prints are star like and the tail is rarely dragged unless in soft mud, sand or snow. Pathways or runs between holes appear as depressions in soil or plants. One feature of the runs or paths is that if they are used over long periods whenever the rat’s body touches an object the fur leaves a dark greasy deposit. They are found in many places associated with man such as farmyards, refuse tips, sewerage systems, game rearing pens and gardens. They can also exist away from these places such as the bottom of hedgerows and in field crops. Shore lines such as the firths around Inverness often attract them and they take virtually any carrion that is found washed up. They swim readily and will colonise islands on lochs and lochans if the food supply on them is adequate.
The origins of the brown rat is thought to have been in Asia, possibly China, and it arrived in Europe in the first part of the 18th century and was first recorded in England in 1720. It was also known as the Norway rat but did not occur in that country until 1762. The black rat came to Britain with the Romans but despite being widespread and in large numbers they were eventually ousted by the brown rat. The population of black rats now in Britain is estimated at fewer than 1,300 which, ironically, makes them one of the rarest mammals in Britain. There is a colony of black rats on the Shiant Islands off the west coast of the Highlands. In contrast the brown rat population for Britain is a minimum of 7 million and in the Highlands they are widespread and only absent from the exposed tops of hills and some marine islands
Part of the success of brown rats is due to their varied diet that includes live food such as slugs, snails, frogs, young mammals and birds eggs. They can travel three to four kilometres a night and can climb well, such as up rough walls and high into trees after birds nests and eggs. They are predated by a wide range of birds and mammals including weasels, stoats, badgers, foxes, tawny and barn owls. Currently tawny owls are taking advantage of the large number of brown rats in the Highlands and are probably the main predator.
Controlling numbers of brown rats has always been a problem and even more so in recent years with the series of mild winters we have just experienced in the Highlands. Predation on sea birds has been a serious problem on islands such as Canna and Handa and there are also problems on the Isle of Rum where predation has taken place on the world famous Manx shearwater colonies on the tops of the hills. There are various poisons that can be used but some of these can cause serious problems to other wildlife and pets by secondary poisoning if they eat dead, poisoned rats. This was so serious with red kites on the Black Isle that a code of conduct was produced.

Ray Collier Country Diary- Snowberries

Snowberries - 8th December 2008

There have been reports from around Inverness and other parts of the Highlands of a shortage of wild berries and fruits this Autumn. Whilst this will mean shortages for wildlife such as the Scandinavian thrushes it will also affect people. The Autumn ritual of collecting berries and fruits for making wine, jams, syrups and soups just did not take place in some areas. In recent years there has been an upsurge of interest in what is popularly called "food for free" and the numbers of books on the subject is a testimony of this pastime. This year, in many parts, people were out but either found a complete lack of berries and fruits or in such small quantities they were not worth collecting.
Blackthorn is a popular source of small blue-black plums called sloes and they are used for making a superb jelly and the traditional liqueur, sloe gin. A less known fact is that the juice of ripe sloes can be used as an indelible marking ink. A well known source of sloes is a line of bushes along a field on the southern edge of Inverness. The normal plan is to assess the crop in late summer but a walk along the two hundred yard long stretch this Autumn revealed just six berries. There were many disappointed people after the first frosts when you are supposed to collect the sloes. In the same area are some old and very large beech trees but very few people bother to collect the mast as the fruits are called. For some reason very few books mention food from the beech although it is in Richard Mabey’s book "Food for Free" the latest edition published in 2001 by HarperCollins. The brown three sided nuts of the beech can be used for cooking oil and for beechnut butter. This Autumn these very impressive beech trees were a rich golden brown as the leaves shone in the sunlight. Not a single beech fruit was found although one explanation could be that good crops only occur every three or four years.
The rowan trees seem to vary considerably although in some areas there were very few berries compared with the last few years. Rowan berries are used to make the famous rowan jelly recommended to be served up with venison. The fresh juice can also be added to gin imparting a flavour like Angostura bitters. Those berries that were there attracted the chaffinches and family parties of mistle thrushes and most trees were soon stripped. This means that the Scandinavian thrushes simply moved through and any fieldfares and redwings still to come will also move south or west until they find some berries.
A look in various parts of the countryside gave a mixed picture for many other berries and fruits. Some areas had a reasonable crop but others were so devoid of them that there is cause for concern. Interestingly in one area the white form of berries of the raspberry seemed to be doing well whilst the normal red form was very scarce. Brambles also seemed very patchy and there were few people out picking them although the poor weather could have been another reason. One exception seemed to be the introduced snowberry that had a rich crop of the conspicuous white berries. These berries are up to 15 mm in diameter and the photograph was taken on the roadside on the Black Isle. Ironically we cannot put this surplus of fruit to any use as it is poisonous. Perhaps all these berries and fruits are cyclic and will be back to normal next year.

Ray Collier Country Diary- Collard Doves

Collard Doves - 22nd December 2008

There are plenty of pigeons and doves, sometimes called doos in the Highlands, in and around Inverness. At this time of the year large flocks of feral pigeons sometimes form of over a hundred birds or more. They will rest on the tops of buildings and, increasingly, they plunder bird tables and feeders in gardens. They compete on the tables and feeders with collared doves and, increasingly, wood pigeons. There seems to be a very variable range of colour in the feral birds and it can all be rather confusing. So what should be called doves and what should be called pigeons? The woodpigeon is straightforward with no other birds interbreeding with them. They are large plump birds with grey upperparts and pinkish underparts. Collared doves often feed with them on bird tables and the photograph was taken of one of these attractive doves on a table near Inverness. The collared dove is now widespread in the Highlands and the Western and Northern Isles. It seems difficult to accept that it did not breed in Britain until the 1950s.
The flocks of so called feral pigeons are a different and more complex matter as far as their origin is concerned. Despite their wide range of variations in colour including black and white ones they are all from the same source namely rock doves. A few decades ago there were three groups of the pigeons. One was the true rock dove that was a species in its own right. It was mainly found along the coasts of the Highlands and Islands where it bred in caves. These colonies were not necessarily remote as there are "doo" caves along the coast of the Black Isle near Ethie. Charles St. John in the 1850s went there and stood outside whilst the rock doves were disturbed and he shot them as they flew out.
Another group of pigeons were in the doocots scattered throughout the Highlands and Northern Isles, but for some reason, not the Western Isles. As these very old buildings fell into disuse the pigeons fared well in the general countryside and as they spread they met and paired successfully with the rock doves. The third group were the pigeons of the lofts holding birds for racing. Some of these birds just never came back, for a wide range of reasons, from their races. They moved into the countryside and they too made contact with rock doves and paired successfully.
The result of the masses of feral pigeons in various parts of the Highlands is that it seems likely that there are no true rock doves now breeding anywhere in the Highlands and Islands. A decade or so ago, perhaps even longer, there were claims that true rock doves still bred in the Western and Northern Isles. The current picture is unclear but what is the fact is that even 15 years ago there was a feral pigeon with a small party of rock doves on North Rona, forty miles north east of Lewis. The current feral flocks cause damage to structures by their droppings and compete with other birds for food, even in gardens within Inverness. To many people they are treasured and people just love feeding them. To others they are called " rats with wings" because they consume so much. Part of their success is that they have been found breeding in every month of the year even in winter. Such is the case in Inverness and other towns simply because the temperature is often several degrees higher that the surrounding countryside.

Ray Collier Country Diary- Herons

Herons - 15th December 2008

Herons, with their very long legs, long necks and large dagger shaped beaks cannot really be confused with any other bird in the Highlands. Whilst there is pink colouring on the beak and legs the plumage is essentially black and white and varying shades of grey. These large birds can be found in wide variety of places and seem equally at home fishing the shallows of the firths to the burns inland. They can be seen in fields where they hunt frogs and small animals such as voles or in the shallow bays of freshwater lochs. They are not averse to coming into garden ponds, even small ones, after goldfish and other types of fish, and if they come in at first light, as they often do, they can take fish before anybody is up in time to see them. They take a very wide variety of freshwater and saltwater fish from sticklebacks to fish so large you wonder how the birds cope. The studies on the herons diet that have been undertaken show that the largest percentage of food in rivers are eels. With such a powerful looking beak it would seem natural to pierce a fish but this approach is unusual. Normally fish, even large one, are gripped rather than skewered, and then there is a great deal of manoeuvring as the fish has to be positioned so that it can be swallowed head first. If the fish is large and struggling then the heron will walk or fly ashore so that if it drops its prey it is not lost in the water.
Whilst part of the success of the heron in recent years is its ability to feed in a wide range of habitats the range of its food is also important. They tend to take fish but will also take large numbers of frogs especially in the spring when the frogs are active and vocal during the mating season. Water birds are also taken especially ducklings whilst dippers have been on their diet. They will also go for larger birds and water rails and moorhens have been recorded. Historically there were few enemies of herons although they were much valued at one time as falconry targets for the peregrine falcon. The problem was that the heron was considered a coward as rather than confront its pursuer it chose to fly ever upwards. Herons also featured on old recipes and were on the menus in many banquets as "heron pudding". Apart from persecution by anglers and fish farms, which still take place albeit illegally, it is severe winters that take their toll. The continuing series of mild winters has meant the birds have increased at some colonies. Another factor has been the clean up of some river catchments areas in recent years which has meant an improvement in numbers and health of fish.
Herons can be seen virtually anywhere in the Highlands and surveys have been carried out at regular intervals so the distribution of their colonies, called heronries, are fairly well known. In last years two volumes of "The Birds of Scotland" from the Scottish Ornithologists Club there is an interesting map of the heronries. Those with more than 30 nests are marked and there are ten of them. Two are near Inverness, on the Black Isle and near Clachnaharry on the west side of Inverness. There are two on the east coast, two on the west coast and four on the Western Isles where one is in a reed bed. There are many other smaller colonies and sometimes only one or two nests are involved.

Ray Collier Country Diary- Mink

Mink - 1st December 2008

Escapes of non-native mammals into the wild have caused serious problems in the Highlands such as the damage to agriculture by the rabbit and sika deer, either introduced for sport such as in Strathdearn south of Inverness or escapes from deer parks such as Rosehall in Sutherland that brought their own problems. Sika are now freely hybridising with red deer to the extent that some people believe there will eventually be no pure red deer anywhere in mainland Scotland. Perhaps the most calamitous of all the introductions has been the North American mink that was originally imported to Britain in the late 1920s with the aim of breeding them in captivity for their valuable pelts. The first mink farms in Scotland were established in 1938 but everyone underestimated the ability of the mink to escape and they soon became established in the wild.
Mink are about the size of a pine marten but slightly smaller with the original wild ones being dark chocolate brown which looks black especially when wet. There is often a white chin patch and the white varies in shape and size so no individual is the same. The mink in captivity were bred to a variety of shades and colours, but once breeding in the feral state the offspring soon revert to the original colour and pattern. The normal litter is five to six and the young are weaned after eight weeks, reach adult size in four months, and can breed the following year. The breeding sites, called dens, have been found in a variety of places such as in tree trunks, and holes and crevices among stones including scree.
Soon after the mink were brought into the "fur-farms" there were reports of escapes and of feral mink living in the wild, but it was not until 1956 that the first breeding was noted. At first the animals were regarded as pests and they were trapped and shot wherever possible, and although thousands were killed it had little effect on the populations. At one time there was even a school of thought that said we might as well accept the mink as an addition to our wildlife as it seemed to be permanently established and in any case eradification did not seem a possibility. As the mink numbers rose and it spread through much of the landscape from hills to coastline and woodland to moorland their effect became more apparent. Part of its success is the very wide range of food they will predate. Rabbits, where common, are a major food but myxymatosis still effects the numbers of rabbits and other food is sought . Mink on the coast can cause havoc in seabird colonies and any ground nesting birds. Breeding birds on islands are often predated such as gulls and terns and some of these colonies were wiped out. Coastal mink will feed on prey found in rock pools such as crab and blenny whilst in rivers they take all species of fish but especially the slow moving ones such as eels. There is evidence that they have had a devastating affect on water voles and on some rivers and burns these increasingly rare mammals have been wiped out. At one time it was thought that mink displaced otters but now the reverse seems the case so there must have been other factors involved. It now seems that where otters moved into rivers and burns the mink move out. Better techniques for capturing mink have now evolved so there is the chance that the numbers of mink can at last be controlled.

Ray Collier Country Diary- Eels

Eels - 24th November 2008

Adult freshwater eels, sometimes called yellow eels, are dark brown along the back and more yellow below. Its serpentine form and slimy body is unmistakable and it is unusual in that the fins extend all along the body to the tail. The front part of the fish is rounded but towards the tail it is more flattened. The scales are transparent, small and deeply-embedded in the skin and laid down as concentric rings. The migration of eels and their life history has been one of the all-time wildlife mysteries and the very early stages are still being solved. The true story was not revealed until the first three decades of the 20th century and it began 2,500 miles away in the Sargasso Sea - so called after the floating seaweed of that name. The eggs have never been found nor, for that matter, no spawning eel has ever been seen. The smallest eels found in the Sargasso were about half an inch long with remains of their yolk sacs which means they were close to their birthplace. They soon start drifting across the Atlantic and reach the coasts of Europe. Round the British coasts the young eels will stay in brackish water for a few weeks and then they begin to move into freshwater. At this stage they are called elvers and in some rivers millions move with the tides, and their exploitation as food has been overtaken by their use to stock rivers in other countries. In the Highlands, these elvers can be seen entering water courses from rivers to burns, some of the latter only two feet across. These tiny eels have been recorded several miles inland trying to scale the dam walls of hydro-electric schemes. They can wriggle through wet moss on the side of waterfalls and they can scale wet, almost vertical, rocks. They are probably the most widespread fish in the Highlands, for a number of reasons, although mainly unrecorded because of their nocturnal and mud dwelling habits. One of these is that large eels have extraordinary means of reaching even land-locked water bodies such as ponds and lochs. The slimy coat of mucus prevents drying and water loss and helps them survive out of water for long periods and they simply wriggle from one area to another. The eel in the photograph was well away from water but it was raining. The British rod- caught record is about 11 lbs but much larger eels have been found either dead or when a loch is drained. Eels have been found weighing 23 lbs and 27 lbs with both being over five feet long. When underwater cameras have explored Loch Ness there have been many sightings of huge eels sliding away on the bottom. Their food depends on their size and a wide range of prey is taken such as snails, frogs, tadpoles, fish eggs and smaller eels. They have many predators, particularly in the smaller stages, and they are a common prey of goosanders and mergansers as well as pike and ferox trout. Herons can often be seen feeding on eels along the Moray Firth and the birds even have special feathers that produce a powder that is used to coagulate the slime of eels so that it can be removed by the bird’s claw. Some eels mature by the time they are nine years old but others have been recorded over 50 years old before they return to the sea and back to the Sargasso to lay eggs and die. When they start the return journey they change colour and are known as silver eels because they are grey backed and silver bellied.