NAMMCO Scientific Publications最新文献

{"title":"Preface- Minke whales, harp and hooded seals: Major predators in the North Atlantic ecosystem","authors":"D. Pike","doi":"10.7557/3.2966","DOIUrl":"https://doi.org/10.7557/3.2966","url":null,"abstract":"","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"2 1","pages":"3-3"},"PeriodicalIF":0.0,"publicationDate":"2014-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First independent feeding of harp seal ( Phoca groenlandica ) and hooded seal ( Cystophora cristata ) pups in the Greenland Sea","authors":"T. Haug, K. Nilssen, Lotta Lindblom","doi":"10.7557/3.2969","DOIUrl":"https://doi.org/10.7557/3.2969","url":null,"abstract":"Data were collected from harp seal ( Phoca groenlandica ) and hooded seal ( Cystophora cristata ) pups belonging to the Greenland Sea (or \"West Ice\") stocks in 1995-1997. Pups of both species were observed to feed independently shortly after weaning, and their first food was almost exclusively crustaceans.  Parathemisto sp., particularly P. libellula , dominated the diet of both the harp and the hooded seal pups, but the diet also contained sympagic amphipods of the genus Gammarus . Krill ( Thysanoessa sp.) was of minor importance as food for seal pups in 1995, but occurred more frequently in the diet of both species in 1996 and 1997. Considerable niche overlap may suggest some interspecific competition between harp and hooded seal pups in the West Ice.","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"2 1","pages":"29-39"},"PeriodicalIF":0.0,"publicationDate":"2014-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introduction - Sealworms in the North Atlantic: Ecology and Population Dynamics","authors":"G. Desportes, G. Mcclelland","doi":"10.7557/3.2955","DOIUrl":"https://doi.org/10.7557/3.2955","url":null,"abstract":"","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"5-6"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patterns of abundance and maturity among three species of parasitic nematodes ( Pseudoterranova decipiens , Contracaecum osculatum , Anisakis simplex ) co-existing in Sable Island grey seals ( Halichoerus grypus )","authors":"G. M. Fowler, W. T. Stobo","doi":"10.7557/3.2964","DOIUrl":"https://doi.org/10.7557/3.2964","url":null,"abstract":"The abundance and maturity of three species of anisakine nematode ( Pseudoterranova decipiens , Contracaecum osculatum , Anisakis simplex ) that co-occurred in the stomachs of Sable Island grey seals were examined in relation to seal growth and seasonal considerations. Sealworm ( P. decipiens ), the predominant nematode in these seals, typically reached numbers of 400 to 2000 worms per stomach. C. osculatum and A. simplex were usually found in much smaller numbers of 40 to 100 and 20 to 60 worms, respectively, per stomach. All three species initially increased in abundance as the seals grew, but after most of a seals’ growth had been attained P. decipiens abundance continued to increase with age, A. simplex numbers either continued to increase or were simply maintained, while C. osculatum abundance declined. Numbers of both P. decipiens and A. simplex declined during winter breeding/pupping and summer moulting fasts or partial fasts, and rose during the regular feeding periods between the fasts. Conversely, numbers of C. osculatum rose during the breeding period, and also during the moulting period in younger seals. We believe this could be attributed to some degree of feeding on prey species in the immediate vicinity of Sable Island that were not preferred during focused feeding periods, and that the inclination to feed during fasting periods decreased as seals grew. An inverse relationship between worm abundance and worm maturity, attributable to the seasonal changes in rates of ingestion of immature worms, was more pronounced for C. osculatum than P. decipiens . C. osculatum was usually represented by much higher proportions of mature worms than P. decipiens . This could be entirely related to the longer periods of time dedicated to feeding than spent breeding or moulting, but higher mortality rates of immature C. osculatum  or greater longevity of mature C. osculatum could also have occurred. A. simplex , generally associated with cetacean species as final hosts, rarely matured in grey seals. We have doubts that the grey seal could be considered a final host for A. simplex .","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"149-160"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surveys of larval sealworm ( Pseudoterranova decipiens ) infection in various fish species sampled from Nova Scotian waters between 1988 and 1996, with an assessment of examination procedures","authors":"G. Mcclelland, D. Martell","doi":"10.7557/3.2959","DOIUrl":"https://doi.org/10.7557/3.2959","url":null,"abstract":"Between November 1988 and October 1996, >10,000 fish from the Breton Shelf, Sable Island Bank and the northeastern Gulf of Maine were examined for larval anisakines. Larval sealworm,  Pseudoterranova decipiens , occurred in 30 of 39 species surveyed, including 8 new host records,  Enchelyopus cimbrius , Lycodes reticulatus , Eumesogrammus praecisus , Lumpenus lumpretaeformis ,  Lumpenus maculatus , Cryptacanthodes maculatus , Artediellus atlanticus and Triglops murrayi . The parasite was most prevalent and abundant in mature demersal piscivores and benthic consumers. Sealworm densities (nr kg-1 host wt.), however, were greatest in small benthophagous fish including mature E. cimbrius , A. atlanticus , T. murrayi and Aspidophoroides monopterygius , and juvenile Hippoglossoides platessoides . ANOVA revealed that geographical disparities in sealworm prevalence and abundance were highly significant in 14 of 20 species tested, although significant disparities between samples from each of the three areas were evident only in H. platessoides . Almost invariably, infection parameters were greatest in fish from Sable Island Bank. ANOVA also indicated that sealworm prevalence and/or abundance increased significantly in Sable Island Bank populations of Gadus morhua , H. platessoides , and seven other species between 1985-1986 and 1989-1990. Routine examinations, in which host flesh was sliced and candled, proved as efficacious as digestion in warm (35° C) pepsin-HCl for detection of larval sealworm in the flesh of large frozen fish. Procedures employing fresh (iced) samples, digestion at ambient temperature and microscopy are recommended, however, for surveys of small benthic consumers. Many of the sealworm infecting the latter hosts are tiny (2 to 10 mm in length) nematodes, which escape detection by routine inspection, and may not survive in warm pepsin-HCl solution.","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"57-76"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution and abundance of sealworm ( Pseudoterranova decipiens ) and other anisakid nematodes in fish and seals in the Gulf of St. Lawrence: potential importance of climatic conditions","authors":"D. Marcogliese","doi":"10.7557/3.2962","DOIUrl":"https://doi.org/10.7557/3.2962","url":null,"abstract":"Prevalence and abundance of sealworm ( Pseudoterranova decipiens ) and other anisakid nematodes were determined in a variety of fishes from the Gulf of St. Lawrence in 1990 and 1992. Sealworm abundance and prevalence were also determined in three species of seals in the Gulf between 1988 and 1992. Atlantic cod ( Gadus morhua ) and shorthorn ( Myoxocephalus scorpius ) and longhorn sculpin ( M. octodecemspinosus ) were the fishes most heavily infected with sealworm. Grey seals ( Halichoerus grypus ) proved to be the most important definitive hosts for sealworm in the Gulf. Abundance of sealworm increased, whereas that of Anisakis simplex and contracaecine nematodes decreased, from north to south in the Gulf. Abundance of sealworm increased compared to earlier surveys in most areas of the Gulf, but decreased in both cod and grey seals during the course of this study. In contrast, abundance of Contracaecum osculatum and Phocascaris spp. in grey seals and cod continued to increase during the study period. Observed increases of nematodes are attributed to growing populations of grey seals (for sealworm) and harp seals (for Contracaecinea). Levels of  A. simplex remained relatively constant between 1988 and 1992 in both grey seals and cod. There is no evidence suggesting that observed patterns in nematode abundance were due to changes in grey seal diet. Nor was there any evidence of competition between P. decipiens and C. osculatum in grey seals affecting either sealworm abundance or fecundity. The trends detected herein are attributed to climatic events in the Gulf of St. Lawrence, where water temperatures in the cold intermediate layer consistently decreased between 1986 and 1994. It is suggested that low temperatures inhibited development and hatching of sealworm eggs, but not those of C. osculatum .","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"113-128"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial and temporal distributions of larval sealworm, Pseudoterranova decipiens (Nematoda: Anisakinae), in Hippoglossoides platessoides (Pleuronectidae) in the Canadian Maritime Region from 1993 to 1999","authors":"G. Mcclelland, D. Martell","doi":"10.7557/3.2960","DOIUrl":"https://doi.org/10.7557/3.2960","url":null,"abstract":"Spatial and temporal trends of larval sealworm ( Pseudoterranova decipiens ) infection in eastern Canadian groundfish were monitored in an indicator host, Canadian plaice ( Hippoglossoides platessoides ), in the 31 to 40 cm length range. Between February 1993 and September 1999, a total of 8,482 plaice were collected from 33 locations in Canadian Maritime waters (NAFO Subdivisions 4TVWX-5ZE), and their fillets and napes were examined for sealworm. Prevalence (P) and abundance (A) of the parasite were greatest (P ranging from 95 to 100%, A from 7.48 to 15.60) in fish collected from the central Scotian shelf (4VSW) near Sable Island, site of the largest grey seal ( Halichoerus grypus ) colony in the northwest Atlantic, and from Jordan Basin in the northeastern Gulf of Maine (4X). The infection of greatest intensity (I=158) occurred in a fish from “The Gully” slopewaters of Banquereau (4VS), a few kilometres northeast of Sable Island. By 1995-99, sealworm prevalence and/or abundance had increased significantly in plaice from most locations where stable or declining infection parameters were observed from 1989 to 1993, but abundance of the parasite continued to decline in the Sable Island area. While spatial and temporal distributions of larval sealworm in plaice seemed largely related to the distribution and growth of grey seal populations, the influence of definitive hosts was probably mitigated by other factors such as changes in environmental temperature and parasite density limiting effects in the indicator host.","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"77-94"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A note on the variation in sealworm ( Pseudoterranova decipiens ) infection in shorthorn sculpin ( Myoxocephalus scorpius ) with host age and size at two locations in Norwegian inshore waters","authors":"K. Andersen","doi":"10.7557/3.2957","DOIUrl":"https://doi.org/10.7557/3.2957","url":null,"abstract":"A total of 540 shorthorn sculpins were collected between 1991 and 1996 from Hvaler and Vega in Norway. The sculpins were caught in traps or by gillnets near seal haul-out sites in both areas. Size, age and intensity of P. decipiens infection were recorded for most fish sampled. Stomach contents of a subsample from each area were examined and the frequencies of occurrence of prey items were determined. Sealworm abundance (mean number of worms in all fish examined) increased significantly with host age and length within given age groups of sculpins from both areas. Sealworm abundance and mean intensity (mean number of worms per infected fish) in sculpins from Vega were lower than those found in the more rapidly growing fish from Hvaler. Abundance of sealworm peaked in 6 year old fish from Vega and in 4 year old fish from Hvaler. Fish and amphipods were the prey items found most frequently in the stomach of fish from Hvaler, while fish and decapods were found most frequently at Vega.","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"39-46"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preface - Sealworms in the North Atlantic: Ecology and Population Dynamics","authors":"S. Grønvik","doi":"10.7557/3.2956","DOIUrl":"https://doi.org/10.7557/3.2956","url":null,"abstract":"","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"3-3"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sealworm ( Pseudoterranova decipiens ) infection in the benthic cottid ( Taurulus bubalis ) in relation to population increase of harbour seal ( Phoca vitulina ) in Skagerrak, Sweden","authors":"S. Lunneryd, K. I. Ugland, P. Aspholm","doi":"10.7557/3.2958","DOIUrl":"https://doi.org/10.7557/3.2958","url":null,"abstract":"In Koster archipelago (northern Skagerrak, Sweden) the harbour seal population increased from approximately 350 to more than 1000 individuals between 1988 and 1998. During the same period, sealworm ( Pseudoterranova decipiens ) abundance in the most heavily infected fish species, bullrout ( Myoxocepahulus scorpius ) and sea scorpion ( Taurulus bubalis ), did not increase. Since harbour seals do not normally feed on those cottids an infection route via cod ( Gadus morhua ), which consume cottids, is proposed. The abundance of sealworm in the final host is therefore related to the probability of cod preying on infected cottids prior to being preyed upon by seals. Our model predicts that the abundance of larval sealworm in benthic fishes is not related to the number of seals when the colony is over a specific threshold size.","PeriodicalId":30560,"journal":{"name":"NAMMCO Scientific Publications","volume":"3 1","pages":"47-55"},"PeriodicalIF":0.0,"publicationDate":"2014-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71335608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}