Helminths of an endangered population of belugas, Delphinapterus leucas, in the St. Lawrence estuary, Canada

1995 ◽  
Vol 73 (8) ◽  
pp. 1402-1409 ◽  
Author(s):  
L. N. Measures ◽  
P. Béland ◽  
D. Martineau ◽  
S. De Guise

Helminths were identified in 38 belugas, Delphinapterus leucas, stranded in the St. Lawrence estuary and Gulf of St. Lawrence during 1984–1993. These helminth species were Anisakis simplex, Contracaecinea sp., Pseudoterranova sp., Stenurus arctomarinus, Pharurus pallasii, Halocercus taurica (new host record), Halocercus monoceris (new host record), Hadwenius seymouri, Diphyllobothrium sp., and Bolbosoma sp. (new host record). Of 21 helminths previously reported from populations of belugas worldwide, 7 were found in the St. Lawrence population. Lungworms, such as Halocercus monoceris, may prove useful in identification of beluga populations in the Arctic and may also be an important cause of morbidity and mortality of calves.

1994 ◽  
Vol 31 (4) ◽  
pp. 444-449 ◽  
Author(s):  
S. De Guise ◽  
A. Lagacé ◽  
P. Béland

A population of 450–500 belugas ( Delphinapterus leucas) resides in the polluted estuary of the St. Lawrence River. Stranded carcasses of this endangered population were recovered and necropsied. High concentrations of organochlorines, heavy metals, and benzo-a-pyrene exposure were demonstrated in tissues of these whales. Between 1988 and 1990, 21 tumors were found in 12 out of 24 carcasses. Among these tumors, six were malignant and 15 were benign. The animals were between 1.5 and >29 years of age, and the ages of animals with and without tumors did not differ when two juvenile animals (1.5 and 3.5 years of age) were excluded. Seven other neoplasms had been reported previously in six out of 21 well-preserved carcasses examined in the same laboratory between 1982 and 1987. Overall, 28 of the 75 confirmed tumors reported so far in cetaceans (37%) were from this small population of beluga whales in the St. Lawrence Estuary. Such a high prevalence of tumors would suggest an influence of contaminants through a direct carcinogenic effect and/or a decreased resistance to the development of tumors in this population.


2000 ◽  
Vol 50 (1-5) ◽  
pp. 67 ◽  
Author(s):  
J.Y. Wilson ◽  
S.R. Cooke ◽  
M.M. Moore ◽  
D. Martineau ◽  
I. Mikaelian ◽  
...  

1998 ◽  
Vol 76 (8) ◽  
pp. 1411-1417 ◽  
Author(s):  
Réjean Hays ◽  
Lena N Measures ◽  
Jean Huot

Capelin (Mallotus villosus) (N = 760) and herring (Clupea harengus) (N = 165) were collected in the St. Lawrence estuary during the summer of 1994 and 1995 to examine the importance of pelagic fish in transmission of Anisakis simplex to cetaceans. Larval A. simplex were removed from fish by means of a pepsin-digest solution or by dissection. Prevalence of A. simplex in dissected capelin was 5%, with a mean intensity of 1.2. Prevalences of A. simplex in herring were 95 and 99%, with mean intensities of 6.2 and 6.8 for pepsin digestion and dissection, respectively. Third-stage larval A. simplex found in capelin and herring were compared with third-stage larvae found in euphausiids and belugas (Delphinapterus leucas) from the St. Lawrence estuary and no differences in size or morphology of larvae from these four hosts were observed. Euphausiids, which harboured moulting second-stage and third-stage larvae, are intermediate hosts of A. simplex. As there was no apparent development of larvae in herring or capelin, these fish are considered to be paratenic hosts of A. simplex in the St. Lawrence estuary.


1990 ◽  
Vol 68 (6) ◽  
pp. 1327-1329 ◽  
Author(s):  
Pierre Béland ◽  
Annick Faucher ◽  
Patrice Corbeil

Several white adult beluga whales (Delphinapterus leucas) were observed to act together with a mother and calf. Underwater sound recordings, group behaviour, and calf appearance and behaviour strongly suggest that the birth had occurred during the observation period. Grey juveniles associated with the group remained at a distance during the whole event. The birth occurred in July during the presumed peak calving season, in a main channel of the St. Lawrence Estuary, home to an endangered population of belugas.


Phytotaxa ◽  
2021 ◽  
Vol 487 (1) ◽  
pp. 56-64
Author(s):  
DIANA S. MARASINGHE ◽  
SINANG HONGSANAN ◽  
SARANYAPHAT BOONMEE ◽  
NING XIE

A novel species, Micropeltis goniothalamicola and a new record Scolecopeltidium menglaense were collected from Mae Fah Luang Botanical Gardens, Thailand. Our new taxon is different from other species in Micropeltis in having relatively smaller ascomata, 6–8-spored asci and 4–5-septate ascospores covering with mucilaginous sheath. Our new record, S. menglaense is the first host recorded from Jasmine grandiflorum (Oleaceae). Morphological comparison coupled with phylogenetic analysis of combined LSU and ITS sequence data provide evidence for the new species and new host record.


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