A HISTORY OF HERTFORDSHIRE 



corone), a bird which is decidedly on the decrease on account of game 

 preserving. In this district there is Elstree reservoir, a piece of water 

 which has considerable attractions for wildfowl, although not to so great 

 an extent as the reservoirs at Tring. 



Of the rarer birds which have occurred in Hertfordshire, one at 

 least has never been recorded elsewhere in the British Isles ; this is the 

 rock thrush (Monticola saxatilis). Amongst other rarities which have 

 from time to time been obtained, may be mentioned the woodchat-shrike 

 (Lanius pomeranus), two-barred crossbill (Loxia bifasciata), rustic bunting 

 (Emberiza rustica), roller (Coracias garru/us), glossy ibis (Plegadis falci- 

 nellus], Pallas's sand grouse (Syrrbaptes paradoxus), and Baillon's crake 

 (Porzana bailloni}. 



I am afraid that the list of disappearing and extinct species includes 

 some very interesting birds. The causes of their disappearance are 

 varied, but all are directly or indirectly due to the influence of man. 

 Of the direct causes, game preserving is responsible for the destruction 

 in many places of birds of prey, though there are fortunately many 

 and increasing instances of game preservers who set a good example by 

 using every effort for the protection of rarer species. The way by which 

 man indirectly destroys and drives away various birds is by enclosing and 

 planting land which was formerly open, and also by the use of the drill 

 and hoe where formerly seed was only scattered broadcast. In those 

 days the great bustard (Otis tardd] and stone-curlew ((Edicnemus crepitans) 

 ran no risk of having their eggs destroyed by the horse-hoe. To the 

 alteration in the aspect of the country caused by planting and 

 enclosures may be partially attributed the non-appearance nowadays of 

 the ' trips ' of dotterel (Eudromias morinellus) which formerly visited the 

 northern hills in the spring and autumn migration, though, no doubt, 

 this can also be accounted for by the decrease of this bird as a breeding 

 species in the British Isles. 



To turn to the more pleasing side of the picture, one could 

 mention many birds, which quite recently were considered rare, but 

 which now are plentiful. This undoubtedly is in many cases due to the 

 very cause which has been inimical to many of the decreasing species, 

 namely, enclosing, planting, and keeping coverts quiet. With no 

 coverts, we should be without many of our warblers, and should only 

 have such small birds as are partial to more open country, few of 

 which are really fine songsters, and thus we should be unable to enjoy 

 one of the greatest pleasures of the country. Civilization has also 

 increased the number of our resident species in another direction. 

 Canals were first introduced into this country to any great extent by the 

 third Duke of Bridgewater, who lived at Ashridge Park ; and it is to 

 canals that we owe the existence of the reservoirs at Tring, which are 

 for the purpose of keeping up the supply of water in the Grand 

 Junction Canal. These reservoirs, of which there are now four, com- 

 prise about two hundred acres of water, the whole of which, with the 



exception of about ten acres, is in Hertfordshire. The sporting rights 



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