786 REPORT—1899. 
tions have been made by an apparatus which covers one square foot bottom surface 
and takes up all invertebrates (bivalves, worms, &c.) living on this. In this way 
it was shown that there are many places where 1,400 bivalves (Abra, Corbula, and 
Solen) live on one square foot bottom surface, and that, for instance, in the Thisted 
Broad, where the plaice grows quicker and becomes larger than in the other Broads, 
food suitable for plaice is not more abundant than in the other Broads. The 
different growth must therefore be owing to the different number of fish per Ténde 
Land: 
In Nissum Broad there are at least 932 plaice per Ténde Land. 
In Kaas Broad ‘s a 375 ” 2 
In Veno Bugt ~ 59 297 of ” 
In Thisted Broad ,, at most 7 Ff} $s 
On July 2, a haul of the seine, under precisely similar conditions as in Nissum 
Broad, was taken in Kaas Broad, which is farther removed from the North Sea 
entrance than the Nissum Broad. This haul yielded only 1,400 plaice, but they 
were of larger size, the majority measuring eight anda half to nine and a half 
inches. My view that the small size and slow growth of the plaice in the Nissum 
Broad is due to overcrowding is confirmed by the interesting experiments in the 
Thisted Broad. One haul was made on July 3, 1899, in this Broad, and thirty-six 
plaice were caught; all these fish were of a larger size than those in the other 
Broads, and their damaged fin-rays showed that they all really were transplanted. 
The transplantation of these fish was made in March and April 1899. This Broad 
is about forty miles from the North Sea entrance at Thyborén, and a few years 
ago contained practically no plaice. Thousands of plaice from seven to ten inches 
in length are now every year transported by the fishermen, partly aided by a 
Government grant, from the North Sea to this Thisted Broad in April, and it has 
been found that, by November of the same year, they have grown to thirteen and 
fifteen inches in length, Generally speaking, these transplanted fish weigh one- 
fifth of a pound when put into the Thisted Broad in April, and weighed one pound 
when taken out in November. 
The cost of transplanting a young plaice from the North Sea is one-sixth of a 
penny, and the value of the plaice, when recaptured in November, is fourpence. 
Last year, between 100,000 and 200,000 were transplanted in this way, and prac- 
tically all the fish were recaptured for the market. 
I believe that there is food enough in the Thisted Broad to support 30,000 
plaice on every square mile, so that 500,000 might be transported to this Broad 
annually. There are other Broads in the Limfjord where there are now no plaice, 
and it is believed that 3,000,000 plaice might be transplanted to the Limfjord 
annually. Should this scheme of fish culture be carried out, there would be an 
enormous increase in the value of the Danish plaice fisheries, There is now before 
the Danish Parliament a bill asking for a grant of 1,000/. a year for transplanting 
these young plaice, with the view of finding out how many of these fish can live 
on each square mile of the fjord and, at the same time, yield an economic result in 
the direction here indicated. 
Although there is at present no definite statistical information on the subject, 
I am of opinion that there is no diminution in the number of small immature 
plaice on the coasts of Denmark. Nature appears to yield a constant and abund- 
ant supply. The supply of food does not seem to be sufficient for the young fish 
in many places. Onthe other hand, my researches in the Cattegat show that there 
large-sized spawning plaice have diminished in number. 
Dr. J. Hjort has this year transplanted from the Danish coast 22,000 small 
plaice to the Christiania fjord in Norway ; it will be most interesting to learn the 
result of his experiments. 
Should these prove successful, there can be little doubt that a similar kind of 
fish culture could be carried on in many of the sea lochs of other countries. 
