IUCN/SSC Otter Specialist Group Bulletin
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IUCN/SCC Otter Specialist Group Bulletin Volume 27 Issue 3 Pages 123- 166 (December 2010)) Citation: Belanger, M., Askin, N., Tan. L. and Wittnich, C. (2010). The History and Current Status of Otter Research within Canada based on Peer Reviewed Journal Articles. IUCN Otter Spec. Group Bull. 27 (3): 127 - 133 The History and Current Status of Otter Research within Canada based on Peer Reviewed Journal Articles Michael Belanger1, Nesime Askin1, Luke Tan1 and Carin Wittnich1 1The Oceanographic Environmental Research Society (OERS) Barrie, Ontario Canada. e-mail:oersdo@gmail.com |
 
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Abstract:In Canada, there are two species of otters, the river otter (Lontra canadensis) and the sea otter (Enhydra lutris). The river otter is considered to be plentiful and ranges throughout a large part of Canada. On the other hand, the sea otter is classified as of Special Concern and only small translocated colonies are found along the coastline of Vancouver Island and British Columbia. The scientific literature was reviewed with respect to both river and sea otter research performed within Canada since 1970 to evaluate the number and topics of research papers that had been published dealing with these otter species. Since 1970, 25 papers have been published, most of the research concentrating on contaminants (mercury, organochlorines) in river otters (80%). There is only 1 scientific paper (1978) dealing with the sea otter (4%). Almost half of publications studying river otters were from or in combination from the province of Ontario (48%). Miscellaneous topics made up 16% of the publications. This paper reveals that in Canada very little scientific work has been published dealing with sea otters and that a huge number of the publications deal with river otters found within the province of Ontario. Thus since 1970, there has been a serious lack of research dealing with either otter species and that most of that work has had no structure or focus. It is hoped that government agencies, the scientific community, non government organizations, and interested groups can organize strategies and granting opportunities to increase the amount of scientific studies to further understand and protect future populations of these 2 species in Canada. |
| Keywords:River otter, sea otter, Lontra canadensis, Enhydra lutris, contaminants |
| Française | Español |
Much of the worldwide research and scientific literature in otters has concentrated on specific species for various reasons. The California and Alaskan sea otter (Enhydra lutris) has been studied due to drastic population declines or changes within their environment. The effect of development and the impact on its population numbers has been examined in the European Eurasian otter (Lutra lutra). Within the North American otter (Lontra canadensis) contaminant levels found within its tissues and their possible impact as well as re-introduction efforts have been published (Gallant, 2007).
It must also be recognized that publications or reports issued by several groups dealing with various aspects of otter conservation or protection have increased the overall knowledge base. Groups such as the International Union for Conservation of Nature and Natural Resources (IUCN) and their Otter Specialists Group (OSG) have published action plans and recommendations to help towards the conservation of otters (IUCN OSG, 2009; Gaydos et al., 2007). However, it is left up to the individual countries within which otters reside to establish strategies for conservation or research. This means that research in a country may be well funded or totally neglected based on several factors such as, but not limited to, the status of a species, conservation efforts of NGOs within that country, research funding opportunities, or even the amount of employment created by any specific project (Goldman, 2009; Nelson, 2009).
Canada has rich environments for both sea and river otters to thrive in. As a result, the sea otter population along the coastline of British Columbia has reached sufficient numbers to be gradually downgraded from being Threatened to that of Special Concern. River otters continue to thrive across Canada in a variety of different habitats. However, both are susceptible to sudden changes (human encroachment) or degradation (pollutants) of their environments (Gaydos et al., 2007). Therefore it is critical to establish the type and amount of research that has been done on these two otter species to prevent any duplication or wastage of funds. It is also essential to look at past scientific data to formulate any future research projects to ensure and promote healthy populations of these two otter species.
MATERIALS AND METHODS
The scientific literature was reviewed using the Pub Med search engine with respect to the number of articles published dealing with the two otter species within Canada. Review papers were excluded from this study as they included other species or combined all of their data without specifying the two otter species present in Canada. Search terms such as otter, Canada, sea otter and river otter were used to find and create the appropriate list of publications dealing with these two species within Canada.
These publications were divided into the following areas: by the author, year of publication, general topic and region where the specimens were acquired. The earliest article found was from 1970 and the latest being published in 2010. A simple percentage calculation was used to derive the following percentages of the publications dealing with sea otter versus river otter, the general topic being discussed or the general region where the specimens were found. For example, there were 20 publications or 84% of the total number (25) of found publications dealing with contaminants in river otters.
RESULTS
From 1970 to 2010 there were 25 papers published in the literature dealing with Canadian sea and river otters. (Table 1) There was only one sea otter paper (1978) that dealt with the re-introduction of that species into British Columbia and it represents 4% of the total number of papers. The remaining 24 papers or 96% report data concerned with river otters. The greatest number of papers (20 or 84%) looked at contaminants within otter tissue or their effects on certain organs. The four remaining papers (16%) dealt with a wide variety of topics. Looking at the publications over time, there were only two (8%) papers published in the 1970's, six (24%) during the 1980's, four (16%) in the 1990's and 13 (52%) since the year 2000.
These papers could also be divided into the various regions where the specimens were taken. The province of Ontario had the majority of papers dealing with river otters (13 or 48%). Nova Scotia was the second province with the second highest number of articles with seven or 29% and British Columbia had four or 21%. The provinces of Quebec, Newfoundland and Alberta each had only one or 4 % of the articles found.
DISCUSSION
There has been a recent recognition of the fact that some species of otters have been studied more than others (Gallant, 2007) and that this lack of scientific knowledge may affect population studies in certain countries (Polednik, 2008). As well, otters have been accepted as top predators that can be used for the conservation of biodiversity and have an impact on public awareness and therefore fund raising opportunities for research projects (Norris, 2009). Therefore it is crucial to understand the research that has been performed and published to better organize conservation efforts. Research that deals with physiology, pollutants, habitat degradation, population status or repopulation efforts are critical in preserving otters worldwide.
Canada is the second largest country after Russia and is composed of approximately 90% land and 10% water (Natural Resources Canada, 2001). Canada also has the longest shoreline of any country (Sebert, 1972). This huge amount of land and coastline allows for large numbers of natural habitats for Canada’s two otter species to thrive in. It is therefore very crucial for any conservation effort dealing with otters within Canada that a large base of information exist that will better direct research into conservation efforts to protect present populations and their environment. There has been a gradual six-fold increase in research work dealing with otters since 1970 (4 in the 1970's and 12 in the 2000's). However with only 25 papers published over 39 years dealing with the two separate species of otters within Canada, it is obvious that there has been and continues to be a serious lack of research programs or projects. As well, most of the research publications have been performed by researchers who have had a specific focus on certain topics such as Wren et al. in the 1980's or Basu et al. from 2005 to 2007, who concentrated their research on contaminants and their effects on river otters.
Although there are other numerous and rich sources of information on Canadian otters such as governmental or non-governmental organizations reports, books, research posters or graduate thesis’, the scope of this paper was to focus on peer reviewed research that is published and readily accessible. As well, the above mentioned sources such as government reports usually summarize the already published scientific peer reviewed papers to promote their policies and rarely add new data to the overall information base.
With the increased use and spread of information via electronic sources such as the Internet, today most libraries and journal publishers make it possible for nearly everyone with a computer to perform literature searches and obtain the required information. As well, it is still very difficult to locate a student’s thesis or very expensive to find/buy a specific book or obtain the proceedings from a specific conference fully describing the posters or lectures. Therefore, the purpose behind this paper was to give the reader the latest status on the quality and quantity of research having been performed and in which areas has been the focus of Canadian otter research. It is hoped that with this knowledge that sustained research programs that focus more on topics such as baseline physiological parameters, health status, population numbers, and environmental conditions which may have an impact on otter long term survivability, is required to be able to preserve future populations of otters and their habitat within Canada.
REFERENCES
Basu, N., Stamler, C., Loua, K., Chan, H. (2005). An
interspecies comparison of mercury inhibition on muscarinic acetylcholine
receptor binding in the cerebral cortex and cerebellum. Toxicol.
Appl. Pharm. 205: 71-76.
Basu, N., Scheuhammer, A., Grochowina, N., Evans, D., O’Brien,
M., Chan, H. (2005). Effects of mercury on neurochemical receptors
in wild river otters (Lontra canadensis). Environ. Sci.
Technol. 39: 3585-3591.
Basu, N., Scheuhammer, A., O’Brien, M. (2007). Polychlorinated
biphenyls, organochlorinated pesticides and polybrominated diphenyl
ethers in the cerebral cortex of wild river otters (Lontra canadensis). Environ.
Pollut. 149: 25-30.
Basu, N., Scheuhammer, A., Evans, R., O’Brien, M., Chan,
H. (2007). Cholinesterase and monoamine oxidase activity in
relation to mercury levels in the cerebral cortex of wild river otters. Hum.
Exp. Toxicol. 26: 213-220.
Bigg, M., Macaskie, I. (1978). Sea otters reestablished
in British Columbia. J. Mammal. 59(4): 874-876.
Cote, D., Stewart, H., Gregory, R., Reynolds, J., Stenson,
G., Miller, E. (2008). Prey selection by marine coastal river
otters (Lontra canadensis) in Newfoundland, Canada. J.
Mammal. 89(4): 1001-1011.
Dewit, T., Clulow, V., Dave, N., Mirka, M., Parker, G., Peterson-Schaffner,
N. (2002). Ra-226 in bone of mink (Mustela vison)
and otter (Lutra canadensis) taken near ‘U’ workings
at Elliot Lake, Canada, and from reference areas with calculation of
transfer parameters. Bull. Environ. Contam. Tox. 68:
878-884.
Elliot, J., Guertin, D., Balke, J. (2008). Chlorinated
hydrocarbon contaminants in feces of river otters from the Southern
Pacific Coast of Canada, 1998-2004. Sci. Total Environ. 398: 58-71.
Evans, R., Addison, E., Villeneuve, MacDonald, K., Joachim,
D. (1998). An examination of spatial variation in mercury
concentration in otter (Lutra canadensis) in South Central
Ontario. Sci. Total Environ. 213: 239-245.
Evans, R., Addison, E., Villeneuve, MacDonald, K., Joachim,
D. (2000). Distribution of inorganic and methylmercury among
tissues in mink (Mustela vison) and otter (Lutra canadensis). Environ.
Res. (Section A). 84: 133-139.
Fortin, C., Beauchamp, G., Dansereau, M., Lariviere, N., Belanger,
D. (2001). Spatial variation in mercury concentrations in
wild mink and river otter carcasses from the James Bay Territory, Quebec,
Canada. Arch. Environ. Contam. Tox. 40: 121-127.
Gallant, D. (2007). Species-wise disparity in scientific
knowledge about otters: an obstacle to development to management and
conservation actions? IUCN Otter Spec. Group Bull.24(1):
5-13.
Gaydos, J., Conrad, P., Gilardi, K., Blundell, G., Ben-David,
M. (2007). Does human proximity affect antibody prevalence
in marine-foraging river otters (Lontra canadensis)? J.
Wildl. Dis. 43(1): 116-123.
Gaydos, J., Miller, W., Gilardi, K., Melli, A., Schwantje,
H., Engelstoft, C., Fritz, H., Conrad, P. (2007). Cryptosporodium
and Giardia in marine foraging river otters (Lontra canadensis)
from the Puget Sound Georgia Basin Ecosystem. J. Parasitol. 93(1): 198-202.
Goldman, R., Tallis, H. (2009). A critical analysis
of ecosystem services as a tool in conservation and partnerships. Ann.
NY Acad. Sci. 1162: 63-78.
Haines, K., Evans, R., O’Brien, M., Evans, H. (2010). Accumulation
of mercury and selenium in the brain of river otters (Lontra canadensis)
and wild mink (Mustela vison) from Nova Scotia. Sci. Total
Environ. 408: 537-542.
Harding, L., Harris, M., Stephan, C., Elliot, E. (1999). Reproductive
and morphological condition of wild mink (Mustela vison) and
river otters (Lontra canadensis) in relation to chlorinated
hydrocarbon contamination. Environ. Health Persp. 107: 141-147.
IUCN Otter Specialists Group. (2009). Otters in Environmental
Impact Assessments Recommendation. www.otterspecialistgroup.org. (Accessed
May 2010).
Klenavic, K., Champoux, L., O’Brien, M., Daoust, P.,
Evans, R., Evans, H. (2008). Mercury concentrations in wild
mink (Mustela vison) and river otters (Lontra canadensis)
collected from eastern and Atlantic Canada: relationship to age and
parasitism. Environ. Pollut. 156: 359-366.
Natural Resources Canada. (2001). Canada Centre for
Remote Sensing. GeoAccess Division.
Nelson, F. (2009). Conservation and aid: designing
more effective investments in Natural Resource Governance Reform. Conserv.
Biol. 23: 1102-1108.
Norris, D., Michalski, F. (2009). Are otters an effective
flagship for the conservation of riparian corridors in an Amazon deforestation
frontier? IUCN Otter Spec. Group Bull. 26(2):
72-76.
Polednik, L., Polednikova, K., Beran, V., Thelenova, J., Valasek,
M., Prasek, V., Skorpikova, V., Dostal, M. (2008). Distribution
of the Eurasian otter (Lutra lutra) in the Republic of Macedonia
in 2007. IUCN Otter Spec. Group Bull.. 25(2):
77-83.
Sebert, L., Munro, M. (1972). Dimensions and areas
of maps of the National Topographic System of Canada. Technical Report
72-1. Ottawa: Department of Energy, Mines and Resources, Surveys and
Mapping Branch.
Somers, J., Goski, B., Barrett, M. (1987). Organochlorine
residues in Northeastern Alberta Otters. Bull. Environ. Contam.
Tox. 39: 783-790.
Stenson, G. (1988). Oestrus and the vaginal smear
cycle of the river otter, Lutra canadensis. Reprod. Fert. 83: 605-610.
Wobeser, G. (1970). Drancunculis iisignis. J.
Wildl. Dis. 6: 88.
Wren, C. (1984). Distribution of metals in tissues
of beaver, raccoon, and otters from Ontario, Canada. Sci. Total
Environ. 34: 177-184.
Wren, C., Stokes, P. (1986). Mercury levels in Ontario
mink and otter relative to food levels and environmental acidification. Can.
J. Zool.. 64: 2854-2859.
Wren, C., Cloutier, N., Lim, T., Dave, N. (1987). Ra-226
concentrations in otter, Lutra canadensis, trapped near Uranium
tailings at Elliot Lake, Ontario. Bull. Environ. Contam. Tox. 38: 209-221.
Wren, C., Fischer, K., Stokes, P. (1988). Levels of
lead, cadmium and other elements in mink and otter from Ontario, Canada. Environ.
Pollut. 52: 193-202.
Wren, C. (1991). Cause effect linkages between chemicals
and populations of mink (Mustela vison) and otter (Lutra
canadensis) in the Great Lakes Basin. J. Toxicol. Env. Health 33: 549-585.
Yates, D., Mayack, D., Munney, K., Evers, D., Major, A., Kaur,
T., Taylor, R. (2005). Mercury levels in mink (Mustela
vison) and river otter (Lutra canadensis) from Northeastern
America. Ecotoxicol.. 14: 263-274.
Résumé : Historique
Et Statut Actuel Des Recherches Sur La Loutre Au Canada Sur La Base De Publications
Scientifiques
Au Canada, il existe deux espèces de loutres, la Loutre de rivière
(Lontra canadensis) et la Loutre de mer (Enhydra lutris). La Loutre de rivière
est considérée comme commune et présente une large distribution
dans ce pays. De l’autre côté, la Loutre de mer est classée « préoccupante » sur
les listes rouges alors que de petites colonies issues de translocations se
répartissent le long des côtes de l’île de Vancouver
et de Colombie britannique. La littérature scientifique a été examinée
pour ces deux espèces afin d’y extraire les recherches menées
au Canada depuis 1970 et évaluer la quantité et la variabilité des
sujets publiés. Depuis 1970, 25 articles ont été publiés,
la plupart des recherches se concentrent sur les contaminants (le mercure,
les organochlorés) dans les loutres de rivière (80%). Il n’existe
qu’un article scientifique (1978) traitant de la Loutre de mer (4%).
Près de la moitié des publications relatives aux loutres de rivière
proviennent ou sont associées à la province d’Ontario
(48%). D’autres sujets très divers ont constitué 16% des
publications. Cet article révèle qu'au Canada très peu
de travaux scientifiques publiés sont consacrés aux loutres de
mer et qu'un grand nombre de publications traitent de la Loutre de rivière
dans la province d'Ontario. Ainsi depuis 1970, il existe un sérieux
manque de recherches portant sur ces deux espèces et la plupart de ces
travaux manquent de structure d’accueil ou d’intérêt.
Il est à espérer que les organismes gouvernementaux, la communauté scientifique,
les organisations non gouvernementales et les groupes intéressés
puissent organiser des stratégies et des opportunités intéressantes
pour développer les études scientifiques qui permettront de mieux
comprendre et protéger au Canada les futures populations de ces deux
espèces.
Revenez au dessus
Resumen: Historia y Estado Actual
de la Investigación sobre Nutrias en Canada, Basado en Articulos
Revisados por Pares
En Canada hay dos especies de nutrias, la nutria de rio (Lontra canadensis)
y la nutria de mar (Enhydra lutris). La nutria de rio es considerada
abundante y se encuentra distribuída a través de una gran parte
de Canada. De otro lado, la nutria de mar está clasificada como en Peligro
Especial y solamente se encuentran pequeñas colonias trasladadas a lo
largo de la linea costera de la isla de Vancouver y Britis Columbia. La literatura
científica fue revisada con respecto a la investigación realizada
en Canada desde 1970 en nutria de rio y de mar, para evaluar el numero y tipo
de publicaciones. Desde 1970, 25 artículos de investigación han
sido publicados, principalmente sobre concentración de contaminantes
(mercurio y compuestos organochlorados) en nutrias de rio (80%). Hay solamente
un artículo (1978) que trata sobre la nutria de mar (4%). Casi la mitad
de las publicaciones estudiaron nutrias de rio que priviened exclusivamente
de la provincia de Ontario y/o de otras provincias (48%). Temas miscellaneos
hicieron el 16% de las publicaciones. Este documento demuestra que hay muy
poco trabajo investigativo en Canada sobre nutrias y que la mayor parte del
que se ha hecho trata de nutrias que provienen de la provincia de Ontario.
Por lo tanto, desde 1970 ha habido una falta seria de investigación
sobre nutrias de rio o de mar y que mucho del trabajo realizado no ha tenido
estructura o un enfoque claro. Se espera que las agencias guvernamentales y
no guvernamentales, la comunidad científica y los grupos de interés
puedan organizar estrategias y garantizar oportunidades para incrementar las
posibilidades de investigación para comprender aún más
y proteger las presentes y futuras poblaciones de estas dos especies en Canada.
Vuelva a la tapa