98 DEPARTMENT OF THE NATAL SERVICE 



8 GEORGE V, A. 1918 



Dr. Martin Murphy who made a special investigation of the distribution of 

 Teredo in Nova Scotia stated that at Sydney Harbour, Cape Breton island, Nova 

 Scotia, T. navalis is " as destructive if not more so than at any of the points on our 

 coast."^ It is abundant along the coasts of Northumberland strait as far west at 

 least as Shediac." How much farther northwest its range extends is not known but 

 probably not much farther. Murphy states that the zone of Teredo's operations on the 

 east coast of Nova Scotia begins about Musquodoboit harbour and extends from there 

 to Whitehaven.- He found that it became scarce on the Atlantic coast between the 

 strait of Canso and Halifax. From Halifax southwest along the Nova Scotia coast 

 only traces of Teredo are found and they are neither numerous nor destructive accord- 

 ing to Murphy. The writer has not observed Teredo on the Bay of Fundy coast of 

 Nova Scotia and Murphy does not appear to have seen it there. Dr. A. G. Huntsman 

 of the St. Andrews biological station informs the writer that " we obtained it once 

 near one of the Western isles, that is very close to Frye's island, in some sunken timber, 

 and at another time we obtained it from some floating blocks which had, quite evidently, 

 drifted in from outside, probably from the Gulf Stream. It is very probable therefore, 

 that Teredo is not indigenous to the Bay of Fundy, but comes in periodically in float- 

 ing wood." Professor Ganong reported in 1885 that " a broad and strong tide-dam 

 was completely undermined and destroyed by them {T. navalis) within the space of 

 six years,"^ at Frye's island which is located in the lower and wider part of the bay. 

 This author at a later date however modified this statement by saying that the destruc- 

 tion of Frye's island was the combined work of Teredo and the crustacean Limnoria 

 Ugnorum. It is possible that it was altogether the work of L. Ugnorum as suggested 

 by Verrill. Whiteaves'* records T. navalis from St. John in a ship's hull. But that 

 this record represents exotic specimens appears certain from Professor Ganong's state- 

 ment that in St. John harbour the Teredo is not only absent but " ships which enter 

 the harbour infested by them are free from them within two days."^ The testimony 

 of Professor Verrill regarding the occurrence of Teredo in the Bay of Fundy is 

 important because of his intimate knowledge of the Bay of Fundy fauna. He writes 

 that " so far as I remember I did not find Teredo navalis in Bay of Fundy during 

 the seven summers I collected there. I think I did find T. norvegica a few times in 

 buoys." . . . "At Eastport, Me., I found Laminaria very abundant in piles, fish- 

 weir stakes, etc., but found no Teredo with it there."^ 



At least three factors are probably active in excluding T. navalis from the Bay 

 of Fundy. Temperature is doubtless one of these. The area in which Teredo is most 

 abundant is, speaking broadly, essentially the same as that of the isolated colonies of 

 oysters in the waters about the southern shore of the gulf of St. Lawrence. Although 

 the waters in winter are much colder than those of the Bay of Fundy, during the 

 critical period of the spawning time they are warmer. Professor E. W. McBride''^ has 

 pointed out how the existence of the oyster in this region depends upon the warming 

 of the water in the shoal areas where alone they can exist during the spawning season. 

 Whiteaves^ still earlier called attention to the special temperature conditions which 

 afforded on the south side of the gulf of St. Lawrence a congenial environment for a 

 northern colony of the Acadian fauna. 



1 Murphy, M. On the Ravages of the Teredo Navalis and Limnoria Ugnorum on Piles and 

 Submerged Timber in Nova Scotia and the means being adopted in other countries to prevent 

 their attack. Proc. and Trans. Nova Scotian Inst. Nat. Sci., Vol. V, Part IV, 1882, pp. 357-376. 



2 Murphy, M. Supplementary Notes on Destroyers of the Submerged Wood of Nova Scotia, 

 Proc. and Trans. N.S. Inst. Sci., Vol. 8, p. 218. 



3 Ganong, W. F. The Economic Molusca of Acadia, N.B. Nat. Hist. Soc. Bull. No. VII,. 

 1888, p. 111. 



4 Catalogue of Marine Invertebrates of Eastern Canada, 1901, p. 151. 



5 Ganong, W. P. Nat. Hist. Soc. N.Y. Bull 4, p. 89, 1885. 



6 Verrill, A. E. Letter to the author, February 21, 1917. 



7 The Canadian Oyster, Can. Rec. Sci., Vol. IX, 1905, pp. 154-5. 



8 Catalogue of Marine Invertebrata of Eastern Canada, p. 15, Can. Geol. Survey, 1901. 



