METEOROLOGICAL CONDITIONS 85 



ing day, Redbreasts, Golden-crested Wrens, Pipits, Wagtails, Hedge 

 Sparrows, and Chats, made their appearance. I even obtained a 

 Wolfs Bluethroat (Sylvia wolfii), a fine old male. From that time 

 onward the migration proceeded undisturbed in its usual course. 



The meteorological conditions hitherto discussed, while un- 

 doubtedly influencing migration in a high degree, yet allow the 

 movement to proceed, though in a manner departing from its 

 normal course. The conditions now to be discussed, on the other 

 hand, are actually the very worst enemies of our shooters and 

 fowlers, inasmuch as they either completely prevent every kind of 

 migration from taking place, or quickly put an end to any migra- 

 tory movement which may have already commenced. 



First and foremost among these deterrent influences we must 

 place fog, during which not a bird is visible. As soon as it 

 makes its appearance the stream of migrants at once rises into 

 clearer strata of the atmosphere, and such of the travellers as may 

 be staying on the island forthwith depart on its approach. Should, 

 notwithstanding, any Snipe be met with at this time, these are 

 invariably so shy and wild that it is next to impossible to get a 

 shot at them. 



It frequently happens in spring that during the early hours of 

 the morning, and in the forenoon, not a bird is to be seen, although 

 the weather is in the highest degree favourable for migratory pur- 

 poses. The cause of this is well known here ; every shooter at once 

 says : ' There must be a fog somewhere.' In such cases the subse- 

 quent weather reports sent by telegraph from the nearest coast of 

 the mainland invariably prove the correctness of this assumption 

 by announcing the prevalence of fog in those parts : or the fog 

 actually makes its appearance here in the course of the day. 



Thus, on 10th March 1880, the conditions were : wind south, 

 light; clear, warm all of such a nature that one would have 

 expected to witness migratory phenomena ; whereas, on the other 

 hand, my journal says : ' Nothing there must be hoar-frost or fog 

 somewhere.' Later on, at five o'clock in the afternoon, we accord- 

 ingly find : ' Wind north-east and east-north-east, fog.' I could give 

 hundreds of similar extracts, but will only mention one or two, 

 which show that the migration does not always completely cease 

 with fog, but in many cases is simply transferred to higher regions 

 of the atmosphere. Thus, on the 9th of February 1878, there was 

 a dense fog from one o'clock A.M. to half-past seven in the evening. 

 At noon, however, the fog happened to clear for a short time, when 

 large flocks of larks were at once seen travelling eastwards in the 

 direction of the spring migration. In regard to the 3rd April 1880, 

 my diary states as follows : ' Wind south-east, light ; fog ; rain 



