242 Enemies of Shrimp ; Colour Varieties. 



decks are washed down and all "rubbish " thrown overboard. 

 Still, we have repeatedly detected fragmentary castings with 

 empty egg shells adherent among the heaps, and found many 

 shrimps in varied stages of moulting. As this process generally 

 takes place in the mature shrimp* after the young are hatched 

 out, it points to the above periods as the decline or close of the 

 true spawning seasons. 



Enemies. Within the Thames estuary, as likewise mouths 

 of the Stour, Medway, Crouch, Blackwater and Colne, fishes 

 and crabs are the worst enemies of shrimps young and old. 

 Among the former we have found the flounder, dab, 

 brill, sole, codling, whiting, rockling, weever, smelt, bass, 

 gurnards, bullheads, eel pout, goby (species), dragonet 

 ("fox"), common tope (the "rigs" and "dogs" of Kent and 

 Essex fishermen), skate and thornback all more or less to feed 

 on shrimps. Perhaps their direst foes are members of the cod 

 family, followed by the gurnards, bullheads, skate and thorn- 

 back. The destruction and havoc that the vast shoals of 

 whitings and codlings commit annually among the shrimp 

 tribe must be something enormous, judging from the crammed 

 stomachfuls of them in the many which we have examined. 



Nor are the Common Shore Crabs (Garcinus msenas) far 

 behind, if we take into account that, at all seasons, they are 

 spread about everywhere, be it mud-flat, shallow shore or 

 deeper water. On occasions on some grounds the trawl will 

 bring up an astonishing multitude of crabs in proportion to 

 shrimps, &c. Then there are the edible and the swimming 

 crabs, &c., which play their part as well ; hence (unless 

 fecundity) it becomes a problem how our estuarine shrimps 

 survive their persistent decimation by man and marine 

 enemies. 



Variations. Regarding albino and parti-coloured or piebald 

 shrimps, these we have found are not altogether uncommon in 



* Moulting, as a matter of fact, is not restricted to the adults, for, as already 

 hinted (supra), when almost of microscopic size, the process is undergone frequently 

 within a brief interval. 



