Forays among the funguses of small wild animals

Forays among the funguses of small wild animals

25 FORAYS AMONG THE FUNGUSES OF SMALL WILD ANIMALS By Mary P.English. General Hospital, Guinea Street, Bristol. The first recorded "Foray among the...

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FORAYS AMONG THE FUNGUSES OF SMALL WILD ANIMALS By Mary P.English.

General Hospital, Guinea Street, Bristol.

The first recorded "Foray among the Funguses" was held in 1868 by that august parent of the B. M. S., the Woolhope Naturalists' Field Club of Herefordshire. Its object was to search out and study the larger British fungi. When in 1896, the B.M.S. was founded, it took over the mycological activities of the Woolhope Club, and one of its functions was to hold an ann,:al foray, an event which is an integral part of our activities today. However, over the years the interests of foraying mycologists have extended and are no longer confined to the larger fungi. At modern forays some members will spend the entire day contentedly examining one rotten log, a pile of wood-chippings, a few square yards of matted grass, or a dozen ageing cow-pats. Men and women of great intellectual distinction can be seen scrabbling in the earth under trees, catching the foam of streams or even reclining comfortably on a grassy bank turning the handle of some ingenuous machine which is said to "foray" in the atmosphere. "Vigorous men of great learning" (London Evening Standard, September 20th, 1964) shatter the woodland peace by attacking the trees with axes. Recently yet another type of forayer has emerged: one who studies the keratinolytic fungi of small wild mammals (SWM). It is immediately obvious that this type of foray presents very special problems owing to the fact that the sought-after fungus is liable to be removed from the grasp of the seeker, often at considerable speed, by its highly mobile substrate. Outwitting the substrate is the prime object of the mycologist studying its fungal flora, and many methods are available to ingenious minds. Since my personal experience is mainly confined to hedgehogs, voles and woodmice, this description of techniques for SWM Forays will be confined to these species. The ideas are by no means all mine, but are distilled from those found most successful by a number of likeminded forayers. Techniques fall into 2 main groups. 1) examination of the animal after its accidental death, a c ornpa r at ive ly peaceful method (for the mycologist), although sometimes messy. 2) catching your quarry alive and releasing it after examination - aesthetically pleasanter than Technique 1, but needing physical agility and the collaboration of a skilled animal ecologist or naturalist. Technique 1. In the case of voles and mice the forayer is almost entirely dependent on the unwilling co-operation of his own or his friends' cats, though break-back traps may sometimes be used. The main difficulty with a cat lies in laying hands on the prey before the rightful owner devours it. Once the mycologist has acquired his dead substrate, collecting the fungi is easy. The animal is simply brushed with a nylon tooth-brush, to the bristles of which the fungi adhere: an agar plate can then be inoculated from the brush. Collecting dead hedgehogs presents different problems. Here one's ally is the motor car, and one's source the country's roads. The keen SWM forayer will always carry in the boot of his car a shovel and a stack of old newspapers. When out driving he will keep a permanent vigil for runover hedgehogs. On seeing one he will stop his car, (re-

26 gardle s s of the inconvenience to other motorists) and, armed with shovel and newspapers, and bravely ignoring the traffic and pitying looks of other drivers, advance on the flattened, bloody mess in the middle of the road, shovel it into a newspaper, and return triumphant to his car. If at all possible, it is best for the mycologist himself to be unable to drive, and so have to get his driving friends to do his dirty work for him. To obtain fungi from a hedgehog, brushing is clearly of little use. Tufts of hair, scale s and spines are therefore removed from various parts of the corpse with forceps and plated on suitable agar. Technique 2. Many skills, some unusual, are needed for this very exciting type of foray. A great deal is learnt from the naturalist with whom one collaborates. With r odents, for instance, it is necessary, to be able to tell a bank vole from a field vole, and to sex both, at a glance. As with dead animals, the brush technique is used for sampling voles and mice and one soon discovers that voles apparently enjoy being brushed (e specially on their tummie s) while wood mice definitely do not, and retaliate by biting viciously. As brushing is usually carried out on the operator's knee, and the animals are inclined to lose control of their bodily functions in their excitement, waterproof trousers are useful garb for the SWM forayer. The Longworth traps in which voles and mice are caught alive, are heavy and cumbersome, so it is also necessary for one of the party to be able to drive a land-rover between trees and through the deep winter mud of woodland rides, in fog if necessary, as delay in clearing pre- set traps results in the death of the animals caught. When a rodent Foray is planned, the traps are set in the afternoon, under the skilled guidance of the collaborator, in a site in which the quarry is known to be abundant. The traps are examined as early as possible the next morning. Very considerable dexterity is needed to extract the animal from the trap and brush it without damaging it or letting it escape. To watch it scuttle happily into the undergrowth when released voluntarily after brushing is highly satisfying, and counteracts the savage frustration felt by the mycologist, when as not infrequently happens, the release of the animal is involuntary and premature. Unlike forays for voles and wood mice, hedgehog forays are carried out at night. Though hedgehogs can run faster than appreciated by the uninitiated, they can usually be caught once they have been seen, and traps are not, therefore, necessary. As hedgehogs are common in gardens, the arm-chair forayer can often achieve a reasonable collection by offering a suitable rewar d to the local children for every animal brought in alive. The more enterprising mycologist, however, will wish to catch his animals himself. Once again, much time is saved by seeking the assistance of an experienced naturalist who knows the favourite haunts of the local hedgehogs. As the animals must be taken home or to "the laboratory for sampling, one goes by car to the selected site, with a number of small cages, and a powerful torch apiece. The summer night is then spent stumbling through trackless rough grass ripping clothes on unseen brambles, hoping to pick up a hedgehog dazzled by the bright light of the torch. An average bag would be 2 or 3 animals a night. A variation of this method, which I have not tried in this country, but which is highly successful in New Zealand, with its comparatively dense hedgehog population, is the foray-by-car. Equipped as just described, the car is driven down likely roads with little traffic, headlights ablaze, until a hedgehog is seen. The car is braked sharply, the forayers leap out, and success depends on whether or not the pursuers can catch the hedgehog before it finds refuge in the roadside vegetation.

27 Sampling a live hedgehog presents many problems, as it will of course roll up when touched. This is a grave disadvantage as its face and sides are the most important sources of keratinolytic fungi. If it is necessary to know from what part of the animal the sample came the hedgehog must be made to unroll. This can be done either by anaesthetising it temporarily or by the "stroking" technique. The former method needs no further discussion: the latter requires much patience and only works with psychologically extroverted hedgehogs. If the spines on the backs of rolled-up animals are stroked firmly from head to tail for long enough, many will unroll, and if the stroking is continued, will remain open for long enough for a second operator to take scales and hair from face and sides for plating out. If it is not necessary to know from exactly what part of the animal the specimen came the "bouncing" technique is infallible. For this the rolled-up anirnal is dropped several times from a height of about 6" on to a piece of paper spread on a hard surface. Any fungi on the animal can be grown from the surprisingly large amounts of scale, hair and spine which are so collected. Some workers using this method have informed me that they have had trouble with hedgehogs unrolling in mid-bounce: these are pre sumably highly extroverted animals which would respond well to the stroking technique. During their temporary captivity, hedgehogs can be fed on bread and milk. If possible they should be freed in the locality in which they were caught. but they will thrive in most gardens, meadows and hedges. While each SWM Foray rnu s t be confined to only a few people and is clearly not suitable for the average B. M. S. field meeting, perhaps fellow members may be interested to learn of this modern extension of "foraying among the funguses". Visit of Prof. A. H. Smith to the TERCENTENARY CELEBRATIONS - ROYAL BOTANICAL GARDEN EDINB URGH - JUNE 1970. It was very pleasing to welcome Prof. A. H. Smith of Ann Arbor, Michigan to the tercentenary celebrations of the Royal Botanic Garden, along with other distinguished guests. Doubly so because Prof. and Mrs Smith stayed on in Edinburgh for a further fortnight after the Scottish Gardens Tour organised as part of these celebrations. During their stay the usage in Europe and North America of names of agarics described originally from the other was discussed in detail. It was concluded that many of the New World names currently used in the New Check List of Agarics and Boleti should not in fact be used at all. Prof. Smith spent much time examining our British and European collections of members of the genus Psathyrella in preparation for his monograph onNorth American species of that genus, and collections of boleti, notes onwhich were to be added to the final draft of his and the book on Bo Ie t aceae of Michigan, by himself and Prof. Harry Thiers which was published last month. Luckily during his stay Peter O'rton« was still working at the Botanic Garden preparing a manuscript and key for Cortinarius III. (i. e. subgenus Hydrocybe) under the sponsorship of the Leverhulme Trust. Thus field observations from all our notes were pooled and discussed with many interesting results. For instance quite unexpectedly we found that we have all been using the wrong concept for Psathyrella sarcocephala - those doubting this should look at Systema Mycologicum again: The weather was extremely dry and although the Smith's were able to see Scotland at its scenic best, collecting was very poor. Neverthe«

28 less a collection of Boletus erythropus allowed a mental comparison to be made with the closely related, North American B. subvelutipes, and two separate collections of two rather unusual members of the Leccinum scabrum complex were made. On another occasion a fine troop of ~­ phalina sphagnicola was found making it possible to demonstrate to Alex. Smith how it differed from O. gerardiana, a North American fungus with very similar habitat requirements. Several colonies of Galer ina paludosa and Tephrocybe palustris were found, the latter accompanied by the very familiar whitish or greyed patches of Sphagnum around the fruit bodies. At least if fungi were lacking the habitats were still present and Prof. and Mrs Smith were able to see our type of scrub-birch, birchbog, native pine, juniper-birch associations, callunetum, shell-sand dunes systems and base-rich fen. This was a very useful exercise because Michigan has no similar communities. Thus when they read that such a species was found und e r birch they will conjure up more of a grassy open woodland with some wet and some dry areas instead of the dense, shaded, wet birch-woods on a muck soil typical of Michigan. The vacuum-cleaned woodlands of the British Isles could also be demonstrated to our North American visitors. Unlike our woods where the forest floor is cleared of most of its woody debris very quickly, so that trunks and large branches do not litter the ground, American woodlands particularly those in the Great Lake Region, Appalachians, Great Smoky Mountains etc, are difficult to collect in because of vast amounts of woody detritus. Felled areas there rapidly grow up with secondary timber, some of which although usually of poor quality is also cut; this latter felling adds to the number of large trunks, stumps and branches already there forming a carpet of detritus in various forms of decay. Thus in anyone such area, usually termed a slashing, from the wasteful practice of leaving to rot all but the saleable timber, one can find habitats ranging from hardly decayed wood to material which is recognisable as being formerly wood only because of its shape; the shape of the stump or trunk is retained by the very rapid growth of roots in the favourable humid atmosphere which exists under the often low canopy. In fact such stumps are simply a mass of soft friable organic 'soil'. It is on such timber that lignicolous agarics are frequently found, often accompanied by species of Hygrophorus, Russula, Lactarius e tc , , species of genera which in Europe one would consider typically terrestrial, indeed often mycorrhizal. Prof. and Mrs Smith were amazed by the differences between the habitats to be found in our countries, even when the plant-community on paper appears to be basically the same or very similar. Perhaps in the past many mycologists have not appreciated this fact sufficiently; thus what is a birch wood? We look forward to welcoming Prof. and Mrs Smith back to the British Isles - perhaps in the autumn of 1971 for the International Mycological Congress. Roy Watling "Peter Orton has been made an Honorary Associate of the Royal Botanic Garden, Edinburgh in recognition of his work, close association with the Garden and the contribution he has made to the Herbarium's comprehensive collections. He has presented his extremely valuable collections of agarics and boleti, made over a twenty-five year period.