130 Mussel Beds; their Produetivity and Mamtenance 



during many visits to the Aberdovey (and other) mussel beds. The 

 economic aspect has always been kept in view, but many of the facts 

 contained in the following pages are probably new, or not yet published, 

 and therefore they may possess some degree of scientific value in other 

 respects also. 



In concludirig these remarks, 1 shall c^uote an article by Professor 

 Irving A. Field, whose works are so often mentioned in the following 

 pages : " In the light of our present knowledge it is proper to say, when 

 viewing a shoal of mussels, 'there is one of the greatest organisations 

 in nature for making flesh food by a short and rapid process.' Surely 

 the humble mussel is fulfilling a benevolent mission in the worlds." 



Acreage of the Aberdovey Mussel Beds. 



It is not necessary to describe in detail the various beds, where, at 

 Aberdovey, the marketable mussels are fished. It has been said already 

 that they lie on the north shore, towards the seaward end of the estuary, 

 where the slope is often very abrupt. This may be anything up to 50°, 

 such being the slope of the river bank (here of solid rock) at Penhehg 

 Point, just east of Aberdovey. In attempting to estimate the dimen- 

 sions of the beds, therefore, it is not sufficient to discover merely their 

 length and breadth, but the angle at. which the river bank slopes has 

 also to be taken into consideration. These several factors were borne 

 in mind during my endeavours to discover the present superficial area 

 of the fishing grounds, early in the present year (1917). Despite all care 

 to ensure a reasonable degree of accuracy, the figures given below must 

 be understood as being merely approximate. In fact, they are probably 

 considerably below, rather than above, the actual figures. 



The approximate total area of the Aberdovey mussel beds is 76,000 

 square feet (= nearly 1| acres). 



(This does not include the great scar towards the Bar.) 



The above figures were obtained from a personal knowledge of the 

 ground, and information supplied by the more experienced fishermen, 

 the whole matter being carefully checked on a large scale map, and in 

 other ways. 



Popidation of the Scars or Seed Areas. 



In an endeavour to estimate the maximum potential jDroductivity 



of mussel beds, when their area is known, it is necessary to find the 



greatest number of individuals of a given size able to live and thrive 



per square unit of measurement in natural conditions. Obviously, all 



^ I. A. Field in The American Museum Journal, October, 1916. 



