176 



THE NATURE BOOK 



plagues from Biblical times to the present 

 day. 



Holinshed. writing of our own country 

 in Queen Elizabeth's reign, says: "About 

 Hallowtide last past (1581), in the marshes 

 of Danesey Hundred, in a place called 

 South Minster, in the county of Essex 



there sodainhe appeared an 



infinite number of mice, which over- 

 whelming the whole earth in the said 

 marshes, did sheare and gnaw the grass 

 by the roots, spoyling and tainting the 

 same with their venimous teeth in such sort 

 that the cattell. which grazed thereon, 

 were smitten with a murraine. and died 

 thereof, which vermine by policie of man 

 could not be destroyed, till at the last it 

 came fo pass that there flocked together 

 such a number of owles, as all the shire 

 was able to yield, whereby the marsh- 

 holders were shortly delivered from the 

 vexation of the said mice. The like of 

 this was also in Kent." 



The report of the Departmental Com- 

 mittee appointed by the Board of Agri- 

 culture in 1892, to inquire into a plague of 

 Field Voles in Scotland, from which the 

 above quotation is immediately derived, 

 forms a very interesting and a very cheap 

 book of natural history.* The area 

 damaged in this particular instance during 

 the years i888-i8gi amounted to not less 

 than sixty miles in length and from twelve 

 to twenty miles in breadth. As is usuall\' 

 the case in matters connected with land, 

 the Committee was confronted with the 

 rival claims of two distinctly opposed 

 interests. On the one hand, in the 

 interest of the farmers, witness after 

 witness testified that the plague was 

 solely to be accounted for by the game- 

 keepers' wanton destruction of winged and 

 ground vermin. On the other hand, in 

 the interest of the game preservers, there 

 was good evidence to show that the 

 destruction of vermin had not been 

 excessive, and that the plague was solely 

 to be accounted for by a succession of 

 mild winters and an abnormal growth of 

 food and cover for the mice. 



The finding of the Committee that the 

 plague was due to a combination of all 

 these causes, and that a ])rom})t organi- 

 sation of the farmers to stamp it out in 



• Ohtaiiiablp throuKh Wvman and Sons, Ltd., 

 Fetter Lane, E.C. Price, is. 4d. 



its early stages would probably have 

 greatly mitigated its severity, will hardly 

 be disputed by anyone who reads the 

 evidence impartially. 



In the course of the inquiry some 

 interesting information with regard to 

 what may be called the climatic cause of 

 the outbreak was obtained. There was 

 indisputable evidence to show that the 

 seasonal conditions which favour a mouse 

 plague are — a wet autumn, a mild winter, 

 ancl a dry spring, in immediate succession. 



A wet autumn results in a luxuriant 

 growth of rough grass, which serves as 

 cover for the mice, and at the same time 

 provides them with unlimited food. By 

 a " mild " winter is meant the absence 

 of black frost of sufficient severity to 

 search their winter burrows. Neither 

 snow nor rain, apart from actual flooding, 

 has any terror for them. Both in this 

 country and in higher latitudes they move 

 freely in tunnels underneath the snow, 

 counting the snow as so much additional 

 cover, while a soft, damp soil in general 

 attracts them. In fact, they normally 

 inhabit marsh-land by reason of its 

 " roughness." A dry spring imphes com- 

 fortable conditions for breecling, and 

 that dryness of the nest which is essential 

 to all young animals. Of these three 

 favourable seasonal conditions I think 

 that the first is perhaps the most 

 important. 



I have already referred to the timid, 

 spiritless character of the Short-tailed 

 Meadow Mouse, and my estimate of him 

 is based, partly on my experience of a 

 large number of captive specimens, and 

 partly on certain observations which I 

 was al)le to make on a small wild com- 

 munity. These observations commenced 

 early in April, igo6, and extended over 

 several weeks. The burrow was situated 

 in the midst of a water-meadow, and the 

 occupants had taken advantage of the 

 roots of an old ash stump to save them- 

 selves unnecessary exertion. My first 

 intimation that the stump — which scarcely 

 rose abo\-e ground level — held tenants, 

 was a momentary flash of brown. The 

 distance was too great for me to deter- 

 mine its origin, but on the next occasion 

 I approached more carefully and satisfied 

 myself that I had a mouse to deal 

 with. Then followed several stealthy ap- 



